106218846 Schlumberger Dowell Lab Manual

SchlumbergerDowell

UKI Drilling Fluids Laboratory Testing

Field Manual

Prepared by : P. Tomkins (EATC) Issued : March 1997

Field Manual Compiled by : M. Sanders (UKI)

Contributions: P. Tomkins (EATC) Reviewed by: D. Williamson M. Sanders (UKI) P. Drecq P. Way (SCR) M. Sanders

M. Hodder (SRPC-D) M. Davison

UKI Revision 2.0 - 1997

Forward

The 1997 UKI Drilling Fluids Laboratory Testing Field Manual was based upon on an abbreviated version of the EATC/UKI Laboratory Procedures Manual, Revision 2.0, January 1997. All the procedures have been reviewed for technical content, and altered accordingly to satisfy local UKI requirements. However, if errors or discrepancies are noted please pass your comments back the UKI laboratory in Aberdeen. You can find us on e.mail at “[email protected]”. This will help improve any future additions. Copies will be supplied with each drilling fluids engineering test kit. Please ensure that they are returned. A copy can also be found in the UKI Lab’s Public folder. All copies will be deemed as being uncontrolled documents.

__________________________ Mark Sanders, UK Laboratory Manager

2 Revision 2.0

Table of Contents : Page

1 Health and Safety 5

1.1Introduction 5

1.2Laboratory Code of Practice 5

1.3Sample Management 7

1.3.1 Sample Labelling 71.3.2 Sample Storage 71.3.3 Waste Disposal 8

1.4Sample Shipping 9

1.5Dowell Non-Analysis Agreements 9

1.5Useful HSE Contacts 11

2 Laboratory Equipment and Chemicals

2.1Introduction 12

2.2Drilling Fluids Product line & C - Codes (Updated May 1996) 12

2.3Standard Mud Kit 17

2.4Summary of Equipment and Chemicals required for Basic Testing 18

2.5Equipment Calibration and Maintenance 21

2.5.1 Calibration Records 222.5.2 CAL/EAF/001 - Mud Balance 232.5.3 CAL/EAF/002 - Pressurised Mud Balance 242.5.4 CAL/EAF/003 - HTHP Fluid loss 252.5.5 CAL/EAF/004 - Retort 262.5.6 CAL/EAF/005 - Fann 35 Rheometer 272.5.7 CAL/EAF/006 - OFI Emulsion Stability Meter 282.5.8 CAL/EAF/007 - Electronic and Mechanical Balances 292.5.9 CAL/EAF/008 - Maintenance of Mixers and Ageing Cells 30

3 Laboratory Mixing Procedures 31

3.1Introduction 31

3.2Technical Notes 31

3.3Mixing Procedures 32

3.3.1 DF/EAF/003 - Low Temperature Water-Based Muds 323.3.2 DF/EAF/004 - High Temperature Water-Based Muds 343.3.3 DF/EAF/006 - Oil and Synthetic Based Muds 37

3 Revision 2.0

Routine Laboratory Testing Procedures 39

4.1Introduction 39

4.2API References 39

4.3Physical Properties 41

4.3.1 DFT/EAF/001 - Mud Weight Determination 414.3.2 DFT/EAF/002 - Viscosity and Gel Strength 414.3.3 DFT/EAF/003 - Low Temperature / Low Pressure Filtration 454.3.4 DFT/EAF/004 - High Temperature / High Pressure Filtration 464.3.5 DFT/EAF/005 - Retort - Water, Oil and Solids 484.3.5 DFT/EAF/006 - Sand Content 49

4.4Chemical Properties 50

4.4.1 DFT/EAF/007 - pH 504.4.2 DFT/EAF/008 - Alkalinity 514.4.3 DFT/EAF/009 - Chloride 534.4.4 DFT/EAF/010 - Total Hardness 554.4.5 DFT/EAF/011 - Calcium Hardness 574.4.6 DFT/EAF/012 - Soluble Carbonates 584.4.7 DFT/EAF/013 - Methylene Blue Test (CEC) 60

for Mud Solids and Shales

5 Non-Routine Laboratory Testing Procedures 61

5.1Introduction 61

5.2DFT/EAF/013 - Particle Size Analysis 61

5.3DFT/EAF/015 - HTHP Rheology - Fann 70 67

5.4DFT/EAF/016 - Pore Plugging Apparatus 72

5.5DFT/EAF/019 - Back Flow Tester 73

5.6DFT/EAF/020 - Mud Solids Monitor (MSM*) 75

5.7DFT/EAF/021 - Fluids Ion Monitor (FIM*) 76

* Mark of Schlumberger

4 Revision 2.0

Section 1 Health and Safety

1. HEALTH AND SAFETY IN THE LABORATORY

1.1 INTRODUCTION

Safety is a legitimate concern and required function of all Dowell laboratories world-wide. Safe working practices are paramount in this environment, in many countries the aspects of laboratory activities are governed by specific legislation and every person engaged in laboratory work must be familiar with this.

All laboratory staff should receive suitable safety training and have a thorough understanding of the relevant legal requirements.

DQM (Dowell Quality Management) can be implemented efficiently in the laboratory by using the quality improvement plan (QIP) and risk identification reports (RIR). Using these methods of communication one can improve the safety and efficiency of your working environment.

1.2 DRILLING FLUIDS LABORATORY CODE OF PRACTICE

∑ Maintain good housekeeping - "KEEP WORK AREA CLEAN, SAFE AND NEAT AT ALL TIMES."

∑ Make yourself aware of all; Emergency exitsEye wash stationsFirst aid boxes

∑ The wearing of safety spectacles is mandatory.

∑ No smoking.

∑ No food or drink.

∑ No mouth pipetting; use pipette fillers provided!

∑ Tirtaions must be performed in fume cupboards.

∑ No trailing hair or clothing such as scarves or ties, particularly if using equipment with moving parts, such as rotary mixers or drills.

∑ ALL chemicals used in the laboratory must have a corresponding MSDS which can be obtained from;Henk Romijn, OIES, P.O. Box 20, 4780 AA Moerdijk, The Netherlands

∑ When performing a test or experiment, always follow the procedure documented in this manual or API 13B to ensure quality control.

∑ All laboratory analysis requests for the UKI laboratory MUST be recorded and documented in the file provided by either the district or region.

∑ Be familiar with Hazard warning labels and MSDS before using a chemical.


∑ When handling acids/alkalis/solvents:-

- Use a fume cupboard (if available)

- Wear gloves

- Follow storage procedures for segregation of non-compatible materials (See EAF procedure - Section 1.3.3)

- Follow the local disposal procedure for acid/alkali and solvent waste.

- Always add acid/alkali to water, not vice versa

∑ When handling ULTIDRILL base oil:-

- Rub in “Travabon” skin protection cream and DO NOT use gloves

OR

- Rub in “Stoko Emulsion” skin protection cream (optional) and wear nitrile gloves

∑ Never store hazardous chemicals, heavy objects or glassware where they are hard to reach or liable to fall.

∑ Use kick-step or ladder to reach high shelves or cupboards.

∑ Be aware of what to do in the event of a spillage or other accident.

∑ Clean up spillage promptly and dispose of waste according to local guidelines

∑ Dispose of sharps and broken glass in the appropriate containers, never unwrapped in a bin.

∑ Dispose of muds and cements according to the local guidelines.

∑ Do not lift heavy items alone.

∑ Label all containers and glassware clearly and mark any hazards - unlabelled substances present a hazard in themselves.

∑ Label any temporary hazards in the lab e.g. "hot", “under pressure”, "wet floor", "acid mixing" etc.


1.3 SAMPLE MANAGEMENT

Samples to give to clients, or to serve as lab standards, can be ordered from Pumptech, Chemical purchasing dept (see introduction). A MATO ( Material Transfer Order) is required and a small charge may be levied.

1.3.1 SAMPLE LABELLING

All samples used in the laboratory must have the proper hazard warning label. Consult the MSDS for details.Make sure that the label, identifies the product or sample name, the sample number is clearly visible, and that the label is securely fixed.

(ii) Samples sent to clients must be clearly marked with the following :Sample name and numberDateHazard warning labelAddress and phone number of the supplying laboratory.

For proprietary Dowell products a non-analysis agreement must be signed by the client or external laboratory prior to sending.

1.3.2 STORAGE OF SAMPLES

Samples must be stored in clearly labelled, airtight containers, away from direct sunlight and extremes of temperature and humidity.

Solvents and acids must be stored in separate cupboards. All solvents labelled as highly flammable must be stored in a metal cupboard or bin. Highly corrosive materials must be stored on suitable trays which limit damage caused by accidental spillage.

The front of these cupboards must be clearly labelled with the appropriate hazard label.

The recommended maximum storage times are given in Section 1.4. The biggest single problem is moisture. This affects primarily polymers and salts. If storage conditions are good (low humidity, air tight seals, etc.) then these storage times can be increased.

Remember : Always make sure that containers are properly resealed after taking out a sample.

Each laboratory must establish its own sample storage policy, which in many cases is dictated by the storage space available.

As a rule, it should not be necessary to keep mud or brine samples (from a rig or brine plant) for longer than 3 months or 1 month after completion of the well whichever is most appropriate.

The use of sample numbers which include the year (as described in Section 2.1) is a very convenient way of identifying old samples for disposal.


1.3.3 WASTE DISPOSAL

Two methods of disposing of waste material are generally available:

∑ Incineration∑ Landfilling

Of the two, incineration is to be preferred, as the waste is effectively destroyed and is no longer a liability of the originator. In landfills, however, the waste remains the responsibility of the originator, who maybe liable for future damage, should the landfill fail and pollute the groundwater.

It will be advantageous to encourage drilling fluids laboratory staff to separate wastes into the following categories:

The following general principles apply :

(i) Water-based muds

Small quantities can normally be disposed of down the drain, but check local regulations first. For larger amounts, or if in doubt, consult your local HSE representative.

(ii) Oil-based and Synthetic-based muds

All oil mud waste must be collected and drummed for return to mud plant or proper disposal (e.g. incineration). Never put oil mud waste down the drain.

(iv) Mud additives

Follow the guidance given in the MSDS. If in doubt, consult your local HSE representative.

(v) Solvents

Collect in sealed metal containers, properly labelled. Do not mix different solvents as resulting mixture could be explosive. Consult your local HSE representative for disposal instructions.

(vi) Aqueous acids and alkalis

Aqueous acids and alkalis may be neutralised and disposed of via the drains, if local authorities permit. Neutralisation is typically performed by adding the acid or alkali to a large volume of water until the pH is measured to be between 6 - 8. Sodium bicarbonate can also be used to render acidic solutions neutral.


1.4 SAMPLE SHIPPING

The UN shipping number for each chemical provides information about the packaging requirements for transportation by air freight. The chemicals commonly sent out by Drilling Fluids do not have a UN number and therefore are not considered hazardous for shipping. However, some products do have UN numbers and are considered hazardous.

Non-Analysis agreements may be required when shipping proprietary Dowell products to client or third party testing laboratories. A template of such an agreement is detailed in Figure 1. This document should be signed, in duplicate, by the Client or third party testing lab and filed accordingly.

Whenever samples are sent out from the laboratory, the following checks must be carried out :

(i) Check contents and labelling (see section 1.3.2)

(ii) Ensure that an MSDS is included with all chemicals (mandatory in many countries). If a mixture of chemicals is to be sent, a list of the additives and quantities must be sent to freight company and they will assess the hazard. The MSDS for each additive must be supplied also.

(iii) Check to make sure that the product is safely packaged. If sending samples by air, check that the packaging is in accordance with published International Air Transport Association (IATA) regulations. The current edition of these regulations is 37th Edition, which came to effect on the 1st January 1996. The IATA regulations are revised annually.

Copies are available from the address shown below :

Orders from Europe and Africa:Publications Assistant Tel : (22) 799.25.25International Air Transport Association Fax : (22) 798-35-53IATA Center Telex : 41558633 Route de l'Aeroport Cable : IATA GENEVAP.O. Box 672 Teletype : GVATPXBCH-1215 Geneva 15 AirportSwitzerland

1.5 DOWELL NON-ANALYSIS AGREEMENTS

A Dowell Non-Analysis agreement must be signed by operator and third party laboratories before any proprietary chemicals are sent out. This is a legally binding document which ensures that no additives or fluid samples are analysed without prior authorisation.

The current UKI Non-Analysis Agreement is detailed over leaf;


Non-Analysis Agreement

Date

“Company name”

Re: Blanket Non-Analysis Agreement with Dowell, a division of Schlumberger Evaluation & Production Services (U.K.) Limited

Gentlemen:

It is our understanding that Company Name is interested in evaluating certain proprietary materials to be supplied to you by Schlumberger Evaluation & Production Services (U.K.) Limited, Dowell division (“Schlumberger”). Schlumberger is willing to permit you to evaluate these materials but considers the chemical composition to be confidential and proprietary to Schlumberger.

To facilitate your evaluation of this material, Schlumberger is willing to furnish you limited research quantities of same on the condition that you will use them only for this stated purpose and that you agree:

(1) not to analyze, have analyzed or otherwise attempt to ascertain the chemical composition of said materials without the prior written consent of Schlumberger;

(2) not to transmit any portion thereof to any third party;

(3) to receive and evaluate samples provided hereunder and to inform Schlumberger of the results of said evaluation and to retain in confidence and not to release nor reveal the results of said evaluation or any confidential information to any third party without the prior written consent of Schlumberger; and

(4) prior to any termination date hereof, to destroy any portion of the material not used for the above stated purpose, and any formulations of articles containing same in a form susceptible to analysis, and to supply, at Schlumberger’s request, written confirmation of destruction to Schlumberger Evaluation & Production Services (U.K.) Limited, Dowell Division, Westhill Industrial Estate, Westhill, Aberdeenshire AB32 6TQ, Scotland.

This agreement is personal to the parties and is nonassignable.

If you are willing to undertake these obligations, please indicate acceptance by signing and returning one original of this agreement.

SCHLUMBERGER EVALUATION & PRODUCTION SERVICES (U.K.) LIMITED (DOWELL DIVISION)

BY__________________________________

John SudderthVice President

AGREED TO AND ACCEPTED this _____ day of ____________, 199____.

“COMPANY NAME”

BY _______________________________

NAME ____________________________

TITLE ____________________________


1.6 HSE CONTACTS FOR DRILLING FLUIDS

For information on safety assessments

Adrian Roach PCF- St Austellc/o ECC Research LabsPar Moor Rd. Par CornwallUK

Tel: (44) 1726 818810 Fax: (44) 1726 818818 E_mail: [email protected]

For information on MSDS of Drilling Fluids additives

Henk RomijnOIESP.O. Box 204780 AA MoerdijkThe NetherlandsTel: (31) 168 332761Fax: (31) 168 327653E_mail: [email protected]

Section 2 Laboratory Equipment and Chemicals

2. LABORATORY EQUIPMENT AND CHEMICALS

2.1 INTRODUCTION

Essential equipment and chemicals are required to set-up a district drilling fluids support laboratory. A stock of drilling fluids additives is required for mixing the fluids in question. Most chemical additives are proprietary to Dowell, although there are numerous exceptions where third party chemicals are utilised and therefore given C-Codes.

To ensure the physical and chemical properties of the mud are measured accurately, it is essential that all mud testing equipment is properly maintained and that the calibration is checked on a regular basis. Equipment must be kept clean and maintained with the appropriate calibration procedures in accordance with ISO 9001. (see section 2.5)

The majority of chemical additives and testing chemicals have a “shelf life”, past which they are regarded as aged and deteriorated.

It is a fundamental prerequisite of all drilling fluids laboratories that equipment is calibrated and chemicals are within their respective shelf life.

2.1 DRILLING FLUIDS PRODUCT LINE AND C-CODES

The products are listed alphabetically and the shelf life given is a guideline.

Product C Code Shelf life

Primary Function

Aluminium Sulphate C134 3 yrs FlocculantAluminium Stearate C133 3 yrsAmmonium Thiocyanate C322 3 yrs TracerAntifoam A C187 3 yrs DefoamerAntifoam S C188 2 yrs DefoamerAP-21 C135 3 yrs DeflocculantAquapac Regular C329 1 yr ViscosifierAquapac LV C330 1 yr Fluid loss additiveAttapulgite C136 3 yrs Viscosifier (high salinity)Barite API C100 3 yrs Weighting agentBarite OCMA C138 3 yrs Weighting agentBarite ARTEP C137 3 yrs Weighting agentBenex C139 3 yrs Bentonite extenderBentonite extender C189 3 yrs Bentonite extenderBentonite API C101 3 yrs ViscosifierBentonite OCMA C140 3 yrs ViscosifierBiozan C359 1 yr ViscosifierBlen-Fyber C717 3 yrs LCMBlown Asphalt C141 3 yrs Fluid Loss ControlBorax C360 1 yr Cross linkerBreake-M C696 BreakerBridgesal Plus C366 Bridging agentBridgesal Plus super fine C364 Bridging agentBrinewate A C957 Completion fluidCalcium bromide 52% liq (sg = 1.70) C370 Completion fluidCalcium bromide Powder 95% C372 2 yrs Completion fluid


Calcium bromide liquor C143 3 yrs Completion fluidCalcium carbonate C376 3 yrs Weighting agentCalcium chloride C400 2 yrs Completion fluidCalcium chloride liquor 35/37% C408 3 yrs Completion fluidCalcium lignosulphonate C145 2 yrs DispersantCALOFLO 100 C302 2 yrs Fluid loss additiveCALOTEMP C300 3 yrs Fluid loss additiveCaustic soda C104 2 yrs pH controlCausticized lignite C419 2 yrs Fluid loss additiveCellophane flakes C420 3 yrs Lost circulation materialChrome-free lignosulphonate C147 2 yrs DispersantChrome lignite C431 2 yrs DepressantCMC Hi Vis Tech C153 1 yr ViscosifierCMC Lo Vis Tech C149 1 yr Fluid loss additiveCMC Lo Vis Pure C152 1 yr Fluid loss additiveCMC Lo Vis Pure C148 1 yr Fluid loss additiveDefoamer C552 2 yrs DefoamerDefoam 2 C457 2 yrs DefoamerDi-Plug C160 3 yrs Lost circulation materialDrilling detergent C191 3 yrs SurfactantDrispac Plus Regular C485 1 yr Fluid loss additive/ ViscosifierDrispac Plus Superlo C906 1 yr Fluid loss additiveDrispac Regular C163 1 yr Fluid loss additive/ ViscosifierDrispac Superlo C164 1 yr Fluid loss additiveFerrochrome lignosulphonate C167 2 yrs DispersantFinagreen Base Oil C500 3 yrs Ester based oilFLOPLEX* C115 1 yr Fluid loss additive (VISPLEX)GELTEMP C193 3 yrs ViscosifierGilsonite C169 3 yrs Fluid loss additiveGuar Gum C171 1 yr ViscosifierGypsum C105 3 yrs InhibitionHF100 Shale Stabiliser C106 3 yrs InhibitionHI-TEMP* Fluid Loss Additive C195 2 yrs Fluid loss additiveHI-TEMP II Fluid Loss Additive C196 2 yrs Fluid loss additiveHYMUL* C197 3 yrs Water Wetting AgentIDBEADS C538 3 yrs Torque ReducerIDBOND L C174 6 mths Shale InhibitorIDBOND P C175 2 yrs Shale InhibitorIDBOND P100 C176 2 yrs Shale InhibitorIDBOND PRD C1003 2 yrs Shale InhibitorIDBRIDGE* C178 2 yrs Bridging agentIDBRIDGE L C179 2 yrs Bridging agentIDBRINE P* C541 2 yrs Completion AdditiveIDCAP* C116 2 yrs Shale Inhibitor (QUADRILL)IDCARB 10 C180 3 yrs Bridging agentIDCARB* 75 C128 3 yrs Bridging agentIDCARB 150 C129 3 yrs Bridging agentIDCARB 300 C843 3 yrs Bridging agentIDCARB 600 C182 3 yrs Bridging agentIDCARB 1500 C543 3 yrs Bridging agentIDCARB 3000 C844 3 yrs Bridging agentIDCIDE* L C185 3 yrs BiocideIDCIDE P C117 3 yrs BiocideIDCLEAN C551 3 yrs DetergentIDF-FLR* C121 1 yr Viscosifier


IDF-FLR XL C122 1 yr Fluid loss additiveIDFAC* Surfactant C186 3 yrs SurfactantIDFILM* 220X C200 3 yrs Corrosion InhibitorIDFILM 620 C202 3 yrs Corrosion InhibitorIDFILM 820X C203 2 yrs Corrosion InhibitorIDFLO* C118 1 yr Fluid loss additiveIDFLO B C204 1 yr Fluid loss additiveIDFLO HTR C120 1 yr Fluid loss additiveIDFLO LT C119 1 yr Fluid loss additiveIDFLOC* C205 3 yrs FlocculantIDFLOC C C206 3 yrs FlocculantIDFLOC OC2P C207 3 yrs FlocculantIDFLOC P C208 3 yrs FlocculantIDFLOC S C556 3 yrs FlocculantIDFREE* C215 2 yrs Stuck pipe freeing agentIDFREE UW C216 3 yrs Stuck pipe freeing agentIDHEC* Breaker C228 2 yrs BreakerIDHEC C227 2 yrs ViscosifierIDHEC L C229 2 yrs ViscosifierIDLUBE* C230 2 yrs LubricantIDLUBE XL C845 2 yrs LubricantIDLUBE 330 C232 2 yrs LubricantIDPAC* C235 1 yr ViscosifierIDPAC XL C236 1 yr Fluid loss additiveIDPLEX* 100 C237 3 yrs Scale InhibitorIDPLEX K C238 3 yrs Scale InhibitorIDSALT* 75 C579 3 yrs Weighting agentIDSALT 250 C578 3 yrs Bridging agentIDSALT C C242 3 yrs Bridging agentIDSALT* FK C846 2 yrs Weighting agentIDSALT FS C240 2 yrs Weighting agent* IDSCAV* 110 C243 1 yr Oxygen ScavengerIDSCAV 210 C581 1 yr Oxygen ScavengerIDSCAV 510 C584 1 yr Oxygen ScavengerIDSCAV ES C245 3 yrs H2S ScavengerIDSEAL* C246 3 yrs Lost circulation materialIDSPERSE* XT C248 3 yrs DispersantIDTEX* C250 3 yrs Shale StabiliserIDTEX W C123 3 yrs Shale StabiliserIDTHIN* 500 C252 3 yrs DispersantIDVIS* C124 1 yr ViscosifierIDVIS D C254 1 yr ViscosifierIDVIS L C256 2 yrs ViscosifierIDWASH* C257 3 yrs DetergentIDWORK* C259 1 yr Viscosifier (completion fluids)IDZAC* C260 1 yr H2S ScavengerINSTAVIS* C261 1 yr ViscosifierINTERDRILL* DEFLOC Thinner C263 3 yrs ThinnerINTERDRILL EMUL C264 3 yrs Primary emulsifierINTERDRILL EMUL HT Emulsifier C265 3 yrs Primary emulsifierINTERDRILL FL Emulsifier C267 3 yrs Fluid loss additiveINTERDRILL LO-RM Rheological C268 3 yrs Low end rheological modifierINTERDRILL LOPOL CP C638 3 yrs Polymeric stabiliserINTERDRILL LOPOL VX C640 3 yrs Polymeric stabiliserINTERDRILL NA C274 3 yrs Fluid loss additive


INTERDRILL NA HT C612 3 yrs Fluid loss additiveINTERDRILL OW C275 3 yrs Oil wetting agentINTERDRILL RM C269 3 yrs Rheological modifierINTERDRILL S C276 3 yrs Fluid loss additiveINTERDRILL VISTONE C281 3 yrs ViscosifierINTERSOLV* H C620 3 yrs Scale DissolverINTERSOLV XFE C282 3 yrs Scale DissolverINTERTREAT* 1600 C621 3 yrs SurfactantINTERTREAT 1777 C622 3 yrs SurfactantIronite Sponge C283 3 yrs H2S ScavengerKWICKCLEAN* C285 3 yrs FlocculantKWICKSEAL* C286 3 yrs Lost circulation materialLignite C103 3 yrs Fluid loss additiveLime C107 1 yr Emulsifier activatorLiquid casing C289 1 yr Liquid casingMagnesium chloride C290 1 yr Base fluidMica C111 3 yrs Lost circulation materialMud Fiber C292 3 yrs Lost circulation materialOML Fiber Lost Circulation C675 3 yrs Lost circulation materialOyster Shells C294 3 yrs Lost circulation materialPOLYLIG Deflocculant C213 2 yrs DeflocculantPOLYTEMP* Fluid Loss C214 1 yr Fluid loss additivePolydrill C295 1 yr Fluid loss additivePotassium Chloride C296 2 yrs InhibitionPotassium Hydroxide C108 1 yr pH controlPotassium Iodide C298 1 yr TracerPotassium Lignite C706 3 yrs Fluid loss additivePotassium Nitrate C707 2 yrs InhibitionPST-100 Temperature C714 1 yr Polymer temperature extenderPTS-200* Temperature C125 3 yrs Polymer temperature extender/

pH bufferPTS-300* Temperature C126 3 yrs Polymer temperature extenderRHEOPOL * C299 1 yr ViscosifierRHEOPOL XL C719 1 yr Fluid loss additiveRHEOPOL GX C331 1 yr ViscosifierSAFEDRILL C723 2 yrs Shale stabiliserSAFELUBE C727 2 yrs LubricantSalt Gel C989 3 yrs Viscosifier (high salinity’s)SM(X)* C217 1 yr ViscosifierSodium Acid Pyrophosphate (SAPP) C301 2 yrs DispersantSoda ash C109 2 yrs calcium treatmentSodium Bicarbonate C110 2 yrs cement treatmentSodium Bromide C764 2 yrs Completion fluidSodium Chloride C302 2 yrs Base fluidSodium Nitrate C304 2 yrs TracerSoltex C305 3yrs Fluid loss additive/lubricantSoltex (Potassium) C776 3 yrs Fluid loss additive/lubricantSTAPLEX 500 Shale Stabiliser C850 3 yrs Shale stabiliserSTAPLEX 650 Shale Stabiliser C465 3 yrs Shale stabiliserStarch C306 1 yr Fluid loss additiveThixsal FL7 plus C501 1 yr Fluid loss additiveThixsal plus C958 1 yr Fluid loss additive/ViscosifierTRUDRILL S* Fluid Loss Additive C218 3 yrs Fluid loss additiveTRUFLO* 100 Fluid Loss Additive C219 3 yrs Fluid loss additiveTRUFLO MVO Fluid Loss Additive C222 3 yrs Fluid loss additive


TRUMUL* Emulsifier C220 3 yrs Primary emulsifierTRUPLEX* Extender C221 3 yrs Organophillic clay extenderTRUSPERSE* Wetting Agent C224 3 yrs Oil wetting agentTRUVIS* Viscosifier C225 3 yrs ViscosifierTRUVIS HT Viscosifier C226 3 yrs ViscosifierULTIDRILL base fluid C380 3 yrs Base fluidULTIDRILL EMUL HT C382 3 yrs Primary emulsifierULTIDRILL FL C383 3 yrs Secondary emulsifierULTIDRILL DEFLOC C385 3 yrs DeflocculantULTIDRILL OW C384 3 yrs Oil wetting agentVen-Chem 208 TBA 3 yrs Fluid loss additiveVen-Chem 222 TBA 3 yrs Fluid loss additiveVISPLEX* Viscosifier C127 1 yr ViscosifierVISPLEX II Viscosifier C132 1 yr ViscosifierWatesal-A C828 2 yrs Weighting agentWood Fiber (C830) C830 3 yrs Lost circulation materialXC polymer C313 1 yr ViscosifierXCD polymer C314 1 yr ViscosifierZinc Bromide Liquor (C315) C315 3 yrs Completion brineZinc Carbonate (C316) C316 3 yrs H2S ScavengerZinc Oxide (C130) C130 3 yrs H2S Scavenger


2.3 STANDARD MUD KIT STANDARD MUD KIT

SMK No : Rig :

Quantity Serial Material Material Status Number Out BackloadedOperator : ( ) Quantity ( ) If

If Included Returned CalibratedEquipment Description Transformer (Step Up / Step Down) 1Fann Viscometer - 6 speed & Stainless Steel Viscometer Cup 1 eachThermo cup 110mL Retort 150mL Retort 1Hamilton Beach Mixer & Stainless Steel Cup 1 eachHot Plate with Magnetic Stirrer 1Emulsion Stability Meter 1HT/HP Filter Press Complete + spare 'O' Rings & Filter Papers 1API Filter Press complete + spare gaskets 1API Mesh Screens 1API Filter Paper - box 2Garret Gas Train (including 'O' Rings & Drager Tubes & excluding Chemicals) 1Pressurised Mud Balance + spare 'O' Rings 1Baroid Mud Balance 2Ohaus Balances - Small & Triple Beam pH Meter 1pH paper 7 - 14 2Hand Crank Centrifuge 1 eachMarsh Funnel 2Mud Cups 4Sand Content Kit 1Calibration Fluid 1Glassware & Miscellaneous 10mL Measuring Cylinder 2 *25mL Measuring Cylinder 2 *50mL Measuring Cylinder 2 *250mL Measuring Cylinder 2 *1 mL Syringe 10 *2 mL Syringe 5 *5 mL Syringe 5 *10mL Syringe 10 *20mL Syringe 5 *1 mL Pipette 3 *2 mL Pipette 3 *5 mL Pipette 3 *10mL Pipette 3 *Pipette Pump 1 *Glass Stirring Rod 1 *100 mL Beaker 2 *100 mL + 250 mL Conical Flasks 2 *Plastic Wash Bottle 500 mL 1 *Stem Thermometers (0 - 220 F & 50 - 500 F) 2 each *Large & Small bottle brushes 2 each *Teflon Tape 1 roll *Steel Wool 3 *Test Procedures Manual 1 *Laminated Safety Posters (non-returnable) 1 *Chemicals WBM / OBMAktaflo E 250 m L 1 OBM *Ammonium Hydroxide (Buffer) 60mL 2 OBM / WBM *Bromo Cresol Green 60mL 2 WBM *Buffers at pH 4,7 & 10 500mL 1 each OBM / WBM *Calver II box of 25 caps 4 OBM / WBM *Carbon Dioxide Cartridges box 15 OBM / WBM *Defoamer (Octanol) 60 mL 1 OBM / WBM *Distilled Water 25 litre 1 *EDTA 0.01M 250mL 2 *Exosol (IPA/Xylene 50:50) litre 4 OBM *Hydrogen Peroxide 3 % 250mL 2 WBM *Manver Indicator 60mL 2 *Methylene Blue 250mL 2 WBM *Methyl Orange 60mL 1 WBM *Nitrous Oxide Cartridges box 5 OBM / WBM *Phenolphthalien 60mL 2 OBM / WBM *Potassium Chloride Standard 250mL 1 KCl WBM *Potassium Chromate (5%) 60mL 2 OBM / WBM *Potassium Hydroxide 8N 60mL 2 OBM / WBM *Silver Nitrate 0.0282N 250mL 2 OBM / WBM *Silver Nitrate 0.282N 250mL 2 OBM / WBM *Sodium Hydroxide 0.1N 250mL 2 OBM / WBM *Sodium Hydroxide 1N 250mL 1 WBM *Sodium Perchlorate Soln 250 mL 1 KCl WBM *Sulphuric Acid 0.02N 250mL 1 OBM / WBM *Sulphuric Acid 0.1N 250mL 2 OBM *Sulphuric Acid 5N 60mL 4 WBM *

2.4 SUMMARY OF EQUIPMENT AND CHEMICALS FOR BASIC DRILLING FLUIDS TESTING

TEST SUBSTRATE EQUIPMENT COMMENTS


Density Mud Mud Balance Calibrate weekly with DI waterPressurised Mud Balance Calibrate weekly with DI water

Funnel Viscosity Mud Marsh FunnelMud Cup

Rheology Mud Viscometer Check Voltage/ HertzPV, YP, Gel Thermocup Check Voltage/ Hertz

Strengths Thermometer Steel, Range 0-250°F

API Filtrate Mud Filtration CellPressurised Nitrogen to 100 psi

Filter Papers 7.1 sq. in size (90mm No. 50 or equiv)

Pressure Regulators to 200 psi

Graduated cylinders 5ml, 10ml, 20ml,50ml

Spares 'O' rings etc.

HTHP Filtrate Mud Filtration cell, stand, receiver, etc. Check Grub screws and 'O' ringsHeating jacket Check voltage

Graduated cylinders 5ml, 10ml, 20ml,50ml

Pressurised Nitrogen to 600 psi

Filter Papers 3.55 in sq. size (2.5" No. 50 or equiv)

Pressure Regulators to 1000 psi

Thermometer Steel, range to 500°F

Spares 'O' rings etc.

Oil/Water/Solids Mud Retort Cells (complete) 50ml preferredcontent Heating jacket Check voltage

Heating Elements Check voltage

Graduated cylinders Same volume as cell

Steel wool Grade 'OO'

Pipe cleaners

Spatula To fit cell

Water wetting agent Small bottle

Sand Content Mud Sieve 200 mesh 2.5" dia.Funnel To fit sieve

Glass measuring tube graduated 0 - 20 %

Cation Exchange Mud Conical flask 250ccCapacity Syringe Glass, 5ml, 10ml

Hot plate Check voltage

Glass stirring rod

Graduated cylinder 50ml

Pipette Graduated 1.0 ml

Hydrogen Peroxide 3% solution

Sulphuric Acid 50ml in dropper bottle

Methylene Blue Solution 3.20g/litre USP grade

Filter Papers Large Diameter


TEST SUBSTRATE EQUIPMENT COMMENTSpH Mud and Filtrate Meter Calibrate daily

Electrodes Store in DI water

Buffer Solutions, bottles, etc. pH 4.0, pH 7.0, pH 10.0

pH sticks Narrow & wide ranges

Distilled Water In wash bottle

Thermometer Glass

Mud/Filtrate Mud and Filtrate Glass syringes 1ml, 5mlAlkalinity Plastic syringes 5ml, 10ml

(Mf/Pf) Plastic titration vessels

(P1/P2) Volumetric pipette 1.0ml

Graduated pipettes 1.0ml, 10ml

Sulphuric Acid 0.02N (N/50)

Hydrochloric Acid 0.02N (N/50)

Sodium Hydroxide Solution 0.1N (N/10)

Barium Chloride Solution 10% at pH 7

Phenolphthalein Indicator

Methyl Orange Indicator

Bromophenol Blue Indicator

Distilled Water Preferably 0.05 µS conductivity

Chloride Filtrate or Ceramic Titration Vesseldetermination Aqueous Sulphuric Acid 0.02N (N/50)

phase in OBM Phenolphthalein Indicator

Potassium Chromate Indicator

Silver Nitrate Solution 0.282N or0.0282N in dark bottles


Divalent Ion Analysis

Filtrate or Aqueous

Ceramic Titration Vessel

(Ca and Mg) phase in OBM Hot plate

Graduated Pipettes 1x5ml, 2x10ml, 1x1ml

pH Sticks

EDTA solution 0.01M, 0.02N

Sodium Hydroxide Buffer Solution 1N NaOH

Calcium Indicator Calver II or Hydroxy Naphthol Blue

Acetic Acid Glacial

Sodium Hypochlorite 5.25% in deionised water

Masking Agent

Ammonia Buffer

Carbonate Garrett Gas Train c/w flowmeter, tubes, diffuser, etc.Determination Regulator

Nitrogen Cartridges

Drager Gas Bag 1 litre capacity

Stopcock & tubing

Drager Hand Pump

Drager CO2 analysis tubes 0.01%

Hypodermic syringes 1.0ml, 2.5ml, 2x10ml

Hypodermic needles 1.5" / 21 gauge

Sulphuric Acid 5N, reagent grade

Octanol Defoamer In dropper bottle

Spare Septa



TEST SUBSTRATE EQUIPMENT COMMENTSPotassium Filtrate Centrifuge Must be capable of 1800rpmDetermination Centrifuge tubes Must be 10ml Kolmer type

(Perchlorate Pipettes 1x0.5ml, 1x1.5m, 1x2.5ml, 1x3.0ml

Method) Syringe 10ml

(STPB Method) Sodium Perchlorate solution 150.0g NaClO4 in 100ml Dist. Water

Standard Potassium Chloride Soln. 14.0g KCl in 100ml distilled water

Distilled water In wash bottle

STPB solution

Quaternary Ammonium Salt Soln.

Sodium Hydroxide Solution 20g / 80ml distilled water

Bromophenol Blue Indicator In dropper Bottle

Graduated Pipettes 1x2.0ml, 2x5.0ml, 2x10ml

Graduated Cylinders 2x25ml, 2x100ml

Beakers 250ml

Filter Funnel

Filter Paper

Calcium Filtrate EDTA solution 0.01M, 0.02NSulphate Detn. Buffer solution 1N NaOH

(versenate Calcium Indicator Calver II or Hydroxy Naphthol Blue

method) Acetic Acid Glacial

Sodium Hypochlorite Solution 5.25% in deionised water

Masking Agent

Volumetric pipettes 1x2.0-5.0-ml, 1x1.0ml, 3x10ml


Ceramic titration vessel

Hotplate

pH sticks

Deionised Water Preferably 0.05 µS conductivity

Total Sulphides Mud Hydrochloric Acid 6N(Alka Seltzer Defoamer Octyl Alcohol

Method) Hydrogen Sulphide Test Paper

Alka Seltzer Tablets

Test Bottle & Cap

Colour Comparison Chart

Syringe 2.5ml



Soluble Filtrate Garrett Gas Train (complete) Tubing, flowmeter, regulators, etc.Sulphides N2 or CO2 cartridges

(Garrett Gas Drager Analysis Tubes 5x H2s 100/a, 5x H2s 0.2%/A

Method) Lead Acetate Paper Discs

Sulphuric Acid 5N reagent grade

Hypodermic syringes 1.0ml, 2.5ml, 2x10ml

Hypodermic needles 1.5" / 21 gauge

Octanol defoamer In dropper bottle


TEST SUBSTRATE EQUIPMENT COMMENTSAlkalinity & Lime

Mud Glass syringes 1ml, 5ml

(OBM only) Plastic syringes 5ml, 10ml

Graduated measuring cylinder 2 x 100 ml

Graduated pipettes 2.0ml, 10ml

Magnetic Stirrer and stirrer bar 1.0ml, 10ml

Beaker 400 mlSulphuric Acid 0.1N N/10

Exosol Made up from a 50/50 Xylene/IPA

Phenolphthalein Indicator


2.5 EQUIPMENT CALIBRATION AND MAINTENANCE PROCEDURES

This section gives the calibration methods for all major items of drilling fluid test equipment and also procedures for ensuring that proper records are kept.

Regular calibration must be carried out on equipment used in the laboratory.

In order to control and monitor calibration effectively, each piece of equipment which requires calibration must be given a serial number. Each item has a record sheet/sheets and every time a particular instrument is checked for calibration, the results must be recorded.

The procedure and frequencies given are based on the manufacturer's recommendations. A calibration sticker must be completed and attached to the equipment, so that its calibration status can be easily accessed.

It should be assumed that any unmarked equipment has not been calibrated.

Any equipment that goes out of calibration and cannot be repaired must not be used. In the case of expensive items like Fann viscometers, specialised external contractors can be used for repair.

Notes :(i) In some instances, it is possible to bring the calibration back to within specification by changing out only a part of the equipment. For example, many calibration problems with Fann viscometers are due to bent bobs which can be replaced.

(ii) Prior to calibration check, the equipment must be cleaned and visually inspected so that obvious defects can be remedied.


2.5.1 Calibration Records

Blank calibration sheets for the equipment in the mud kit are given below.

Figure 2. INSTRUMENT CALIBRATION/MAINTENANCE RECORD TEMPLATE

Instrument :

Manufacturer and model :

Serial Number :

Calibration procedure :

Calibration frequency :

Calibration limits :

Responsibility :

DATE RESULT COMMENTS SIGNED


2.5.2 PROCEDURE CAL/EAF/001 - Mud Balance

The calibration of the mud balance is unlikely to change, unless damaged in some way, but its calibration must be checked to ensure accurate results are obtainable. The following method should be adhered to.

1 Ensure the balance is thoroughly cleaned as even small deposits of mud on the balance or rider can cause improper readings. Check that it is not physically damaged.

2 Place the base stand on a level surface.

3 Fill the balance cup with fresh water. The temperature of the water must be at 70°F (21°C), approximately room temperature. Tap the side of the balance several times to remove any entrained air and then place the lid onto the balance cup by pushing it downwards with a slow rotating motion until it is firmly seated. Ensure that some water is forced through the vent hole.

4 Dry off any excess water from the outside of the balance.

5 Place the knife edge of the balance onto the fulcrum and check the reading by moving the rider along the arm. (it is balanced when the bubble is equidistant from the centre lines). Do not let either end of the balance touch the case during this process - it can pick up dirt and give a false ready.

6 Record the reading from the side of the rider nearest the balance cup. (i.e. the arrow pointing to the mark).

7 The measurement reading should be 8.34 lbs/gal and is marked with a longer scale division called the water line.

8 If the mud balance gives improper readings, remove the screw cover from the weight adjustment compartment and add or remove lead shot until the balance is correctly calibrated.

Calibration frequency : Weekly


2.5.3 PROCEDURE CAL/EAF/002 - Pressurised Mud Balance

Unless damaged, the calibration of a pressurised mud balance us unlikely to change, but due to the crucial nature of the results it provides, its calibration is equally important. The following method must be adhered to.

1 Ensure the balance is thoroughly cleaned, as even small deposits of mud on the balance arm or rider can cause incorrect readings. Check that it is not physically damaged.

2 Place the base stand on a level surface.

3 Fill the balance cup with fresh water. The temperature of the water should be at 70°F (21°C), approximately room temperature. The cup must be filled to a level slightly below the upper edge of the cup -approximately 1/4" (0.5 cm).

4 Place the lid on the cup with the attached check valve in the down (open) position. Push the lid downward into the mouth of the cup until surface contact is made between the outer skirt of the lid and the upper edge of the cup. Any excess water will be discharge through the check valve. When the lid has been placed on the cup, pull the check valve up in the closed position, rinse off the cup and threads with water and then screw the threaded cap on the cup.

5 Submerge the nose of the plunger in the water with the piston rod completely depressed. Draw the position rod upwards, thus filling the cylinder with water.

6 Push the nose of the plunger onto the machine O' ring surface of the valve. Pressurise the cup by pushing downwards on the cylinder housing and piston rod simultaneously.

7 Once the pressure is actuated and the valve has closed, disconnect the plunger.

8 Place the balance on the knife edge and slide the weight left or right until the beam is balanced i.e. when the level bubble is centred between two black marks.

9 The reading should be 8.34 lb/gal and is marked with a longer scale division called the water line.

10 If the balance gives incorrect readings, remove the screw cover from the weight adjustment compartment and add or remove lead shot until the balance is correctly calibrated.

11 To release the pressure, reconnect the empty plunger and push downwards on the cylinder housing. The cup can then be emptied and dried off.

12 The valve, lid and cylinder should be frequently greased with a waterproof grease.

Calibration frequency : Weekly


2.5.4 PROCEDURE CAL/EAF/003 - HTHP Fluid Loss Equipment

Faulty equipment when using high temperatures and high pressures can lead to serious accidents, in addition to inaccurate data. Therefore, it is essential that all equipment is maintained and calibrated. All apparatus must be cold and under zero pressure before maintenance or calibration begins.

1 Check the lead and plug for wear and replace if necessary

2 Plug in and place the thermometer in the jacket thermometer housing.

3 Allow the jacket to heat up to 350°F, approximately 6.5 on the adjustment scale. This is the uppermost temperature required of the equipment. The pilot light should come on when the temperature has stabilised. If it does not - replace it.

4 ‘O’ rings and valves must be checked for wear or blockage and replaced if required.

5 The filter screen must be checked for wear (i.e. sharp ends or holes) and replaced if required.

6 The grub screws and screw wells must be checked for wear and replaced if necessary.

7 Check that the pressure gauges are not damaged and that the needles are free (i.e. not sticking against the scale or glass).

8 Connect regulators to HT/HP cell and pressurise to working conditions (i.e. bottom regulator : 100 psi; top regulator : 600 psi).

9 Allow to stand for 30 minutes. There should be no loss of pressure from either regulator, during this period.

Safety Notes :

1 Never use nitrous oxide cartridges on HT/HP equipment.

2 Care must be taken releasing the pressure and dismantling the equipment. (see section 4.3.4)

Notes :

All pressure gauges are calibrated yearly. Each gauge is individually identified and referenced to a calibration certificate. The certificate number is given in the gauge inspection column.

ST 508 Digital thermometers calibration records should be traceable to national standards.

Maintenance frequency : monthly

Pressure gauge calibration frequency : Annually

Digital thermometer calibration frequency : Annually


2.5.5 PROCEDURE CAL/EAF/004- Retort

1. Visual Inspection :

The following must be checked for wear and replaced as necessary :

Check listCablePlugsSocketsRetort chamber (for cracking)Also check the screw threads for damage and ensure that the retort can beproperly assembled.

2. Temperature Control :

(i) Place thermocup in heating block(ii) Switch on retort(iii) Once retort temperature has stabilised (i.e. indicator light has gone off),

the temperature should be 600°F +/- 50°F (10 mL retort) and 1,000°F +/- 50°F (50 mL retort) as measured with a calibrated thermocouple or digital thermometer.

(iv) Adjust control screw if necessary. (Clockwise to make it hotter, counter-clockwise to make it cooler).

3. Chamber Volume

(i) Clean and dry the sample chamber (50ml or 20 ml) thoroughly.(ii) Place the empty sample chamber with lid on an electronic balance and

tare.(iii) Fill sample chamber with deionised water and replace lid, ensuring some water

is displaced through drain hole.(iv) Place a finger over the drain hole and dry sample container surface thoroughly. (v) Reweigh sample container with water and lid

Results 50 mL Retort = 50 g deionised water (+/- 0.25 g)

20 mL Retort = 20 g deionised water (+/- 0.1 g)

Temperature Control calibration frequency : AnnuallyChamber volume calibration frequency : Monthly


2.5.6 PROCEDURE CAL/EAF/005 - Fann 35 Rheometer

1. Ensure the bob, rotor and heating cup are clean and dry.

2. Fill the heating cup with the Dow Corning 200 calibration fluid and adjust the heating cup until the fluid reaches the correct level on the rotor (marked by line).

3. As a minimum, readings should be taken at both 300 and 600 rpms. Start the viscometer on the 600 rpm reading and record, followed by the 300 reading, allowing at least two minutes on each speed for the dial to stabilise.

4. Check and record the temperature of the calibration fluid, using either a calibrated thermocouple, digital thermometer or mercury thermometer.

5. Check readings against calibration chart (as supplied with each batch of oil). Check the ref. no. of the fluid corresponds with calibration chart ref. Record figures from the chart. Note : the chart from the supplier will normally only give the 300 rpm reading. For the 600 rpm reading simply multiply the 300 rpm reading by two.

6. The readings obtained should be within 2 points of those specified on the calibration chart.

7. If the viscometer is found to be out of calibration, it must be re-calibrated by trained laboratory personnel.

N.B. 1. ST 508 digital thermometers calibration records should be traceable to national standards.

2. The Dow Corning 200 calibration fluid can be obtained from OFI or from :

Hilton Instruments32 Holland StreetAberdeen AB2 3UL

Tel. (44) 224 620121Fax : (44) 224 20125

This company also undertakes viscometer repairs.

Viscometer calibration frequency : Monthly Thermometers calibration frequency : Annually


2.5.7 PROCEDURE CAL/EAF/006 - OFI Emulsion Stability Meter

Make : OFIModel : ESM-20/ESM-30

1. Battery Condition

Check the low battery indicator, located at the top left corner of the display. If this is indicated replace the batteries (9 volt alkaline)

2. Meter Condition

Place the calibration probe into the probe socket and depress the power source button. On the ESM 30, the reading should be 915 volts +/- 2%. On the ESM 20, the reading should be 750 volts +/- 5%. If the reading is outside the specification refer to stage 4 for re-calibration of the meter.

3. Probe Condition

It is essential that the probe is scrupulously clean before checking is initiated. Check the probe for any damage (i.e. cracks or loose connections). If there are no visible defects, connect the probe to the meter and immerse the electrodes at the tip of the probe in clean diesel/base oil. The reading should be 1999 or >2000 depending on the age of the meter. Any reading less than these will warrant replacement of the probe.

4. Meter Re-calibration

a. Remove the circuit board plastic cover.b. Make a small adjustment to potentiometer R5 and recheck reading with calibration probe.C. Repeat step 2 until correct reading is obtained with the calibration probe.

Calibration frequency : Monthly


2.5.8 PROCEDURE CAL/EAF/007 - Electronic and Mechanical Balances

Ideally every balance should be checked with a minimum of two calibration weights which span the scale on which the balance is being used. For electronic balances, it is recommended that calibration is carried out by the manufacturer or by external contractors as far as possible.

1. Ensure the calibration weights and balance plate are thoroughly clean and zero the balance.2. Place calibration weight no. 1 on the balance plate and record figure given by balance.3. Repeat stage 2 with weight no. 24. The weights recorded must be within the error limits as stated below.

Balance Calibration weight to use

a. Ohaus balance model 311-00 10g and 100gb. Ohaus balance model 760-00 100g & 1 kgc. Sauter balance model RC8021 1.0g, 10.0g,100.0g & 1 kgd. Mettler balance model PE3600 1.0g, 10.0g,100.0g & 1 kge. Oertling balance model LA164 0.01g, 1.0g, 10g & 100g

Error limits

Balance Calibration weight ErrorOhaus model 311-00 10g +/- 0.05gOhaus model 311-00 100g +/- 0.05gOhaus model 760-00 100g +/-0.5gOhaus model 760-00 1 kg +/- 0.5gSauter 1.0kg - 100.00g +/- 0.1gSauter 1kg +/-0.5gMettler 1.0g - 10.0g +/-0.01gMettler 100g +/-0.1gMettler 1 kg +/-0.5gOertling 0.01g +/-0.0002gOertling 100g +/-0.001g

Calibration frequency : monthlyWeight calibration frequency : yearlyN.B. Each weight should be traceable to national standards.Ref: UK National Physical Laboratory (NPL) certified E2 standards of mass. NPL ref. M25/MW 465-134 and M29/MW 475-159).


2.5.9 PROCEDURE CAL/EAF/008 - Maintenance of Mixing and Ageing Equipment

(i) Hamilton Beach Mixers / Silverson Mixers

Keep mixers clean when not in use. Check mixer heads (blades) regularly for wear (e.g.. by loss of weight). Check shaft speeds regularly using a calibrated tachometer.

N.B. Variations in above can affect results.

(ii) Ageing Cells/Bombs

Clean hot rolling bombs thoroughly after use. Check valve stems and O' rings for wear and corrosion and replace regularly.

If ageing temperatures exceed 300 deg F, then replace valve stem ‘O’ rings as a matter of course.

Grease the threads and grub screws. Use anti-stick compound. Check the rolling bombs periodically for signs of corrosion.

Note that stainless steel bombs will corrode if used regularly with salt-containing water base muds. Inconel alloy bombs are available for this application and will last much longer (but are expensive).

If possible, designate specific bombs for water based muds and oil-based muds

(iii) Ovens

Inspect ovens regularly and check that the chain drive is not slack

Check that fan is working

The temperature must be monitored with a calibrated thermocouple connected to a chart recorder. This does not need to be done routinely but should be done as a calibration check on each oven once a month.

Section 3 Laboratory Testing Procedures

3 LABORATORY MIXING PROCEDURES

3.1 INTRODUCTION

The following sub-sections describe the standard procedures for the preparation of drilling fluids samples in EAF laboratories. These procedures are given as general guidelines for WBM and OBM preparations and are not specific to individual formulations.

It is widely recognised that consistent mixing of laboratory drilling fluids formulations is a critical process in ensuring representative and reproducible final fluid properties. Factors such as, order of addition, mixing time, shear history and ageing conditions are just a few of the many variables, that if not controlled can result in widely differing properties for any given formulation.

It is for this reason that mixing procedures must be standardised.

3.2 TECHNICAL NOTES

∑ Ensure a “Laboratory Analysis Request”, (LAR) is completed and issued prior to commencing laboratory work to ensure the objectives are clear, concise and achievable.

∑ The LAR template has been included at the back of the manual. Copies can also be obtained from the UKI laboratory.

∑ Measure all product additions by weight if possible.

∑ Always use pre-hydrated bentonite unless otherwise stated.

∑ Ensure correct grade of bentonite is used.

∑ Adjust pH to desired value, before and after hot rolling.

∑ Duplicate formulations to ensure results are repeatable.

∑ Document in detail all lab results and observations.

∑ PLEASE CONTACT THE UKI LABORATORY FOR FURTHER DETAILS ON LABORATORY PROCEDURES IF REQUIRED


3.3.1 PROCEDURE DF/EAF/003 - Low Temperature Water-Based Muds(350 ml - 1 Lab Barrel)

This procedure is generally applicable for the following drilling fluid systems;Freshwater bentonite mudsSeawater bentonite mudsBentonite / polymer mudsLime mudsGyp mudsPolymer mudsSalt saturated mudsKCl - polymer mudsQUADRILL LT

A EQUIPMENT

a) Balance: precision ± 0.1 gb) Hamilton beach mixer and cupc) Weighing boatsd) Spatulae) pH meter: precision ± 0.1 pH

B. ORDER OF ADDITION

1. Prehydrated bentonite (as described in DF/EAF/001)2. Fresh water or seawater3. Polymeric additive4. Salts s5. Caustic soda6. Weighting agent7. Simulated drilled solids e.g. Rev Dust, Hymod Prima, OCMA drilled solids.

C. PROCEDURE

1. Add the required weight of prehydrated bentonite followed by the required amount of water and salts to a Hamilton beach cup. Mix for 5 minutes on low speed (11,000 rpm ± 300 rpm) and adjust the pH as required with caustic soda.(Note : this 5 minute mixing is not required if no bentonite or salt is added!)

2. Add high molecular weight viscosifying and encapsulating polymers slowly into the vortex over a five minute period, ensuring that all polymer has completely dispersed and that none adheres to the sides of the mixing vessel or the mixer shaft. Mix for a further 5 minutes.

3. Add all other powdered additives slowly into the vortex over a one minute period, excluding barite and simulated drill solids). Mix for a further 4 minutes.

3. Add all other liquid additives, E.g.. Staplex 500, adding these slowly via a syringe over a 1 minute period. Allow one minute between each addition. Readjust pH if necessary. Mix for a further 4 minutes.

4. Add the weighting material (e.g.. Barite) slowly into the vortex over a 2 minute period. Mix for a further 8 minutes.

5. Add the simulated drilled solids into the vortex over a 1 minute period. (E.g.. Rev Dust, Hymod Prima)

8. Continue to mix the whole mud for the remaining time in the hour i.e. 14 minutes


9. Cover and allow to stand for 1 hour before testing to allow the fluid to equilibrate and any entrained air to escape.

10. Test and age as required.

Safety Notes :

∑ Adjusting pH

(i) Unless the quantity of caustic soda is defined in the formulation, it is recommended that a caustic soda solution (e.g. 50% w/w) be used for pH adjustment. Use drop wise from dropper bottle

(ii) Disposable plastic gloves and safety glasses are to be worn at all times, when handling caustic soda (solid or solution).

(iii) Prevent splashes - but if any occur mop up immediately.

(iv) When measuring pH, hold the pH probe against side of "cup". Do not allow it to touch the rotating shaft.

.

Procedural notes :

∑ Ensure temperature of fluid does not exceed 150 0F during the mixing process by mix. Cool mixture in a water bath.

∑ If excessive foaming occurs during mixing, then dropwise addition of a defoamer (Octanol or Antifoam S) may be added to alleviate the situation.

∑ Final mud formulations must be performed in duplicate to ensure reproducibility and ultimately reliability.

SUMMARISED MIXING PROCEDURE FOR LOW TEMPERATURE WATER-BASED MUDS

ORDER OF ADDITION

Add after Time (mins)

Addition time (mins)

Mix time (mins)

Examples of typical products in the Dowell DF line.

Prehydrated Gel 0 - 5 Non-Treated BentoniteSalts 5 1 9 KCl, NaCl, CaSO4, Ca(OH)2Viscosifying / Encapsulating Polymers

15 5 5 Idvis, IDF-FLR, Idbond, CMC HV, Biozan, XCD, Idcap, Guar, Idpac, Rheopol GX, Visplex II

Fluid loss Control additives

25 1 4 IDF-FLR XL, Idflo, Idpac XL,Floplex

Other liquid additives

30 1 4 Staplex 500, Staplex 650, Idfilm, Idlube, Idcide

Weighting agent 35 1 - 2 8 - 9 Barite, Micromax, HaematiteDrilled Solids 45 1 14 Rev Dust, OCMA, Hymod

Prima


3.3.2 PROCEDURE DF/EAF/004 - High Temp Water-Based Muds (350 ml - 1 Lab Barrel)

This procedure is generally applicable for the following drilling fluid systems;CALODRILLHITEMPQUADRILL HT

HTHP fluids are generally described as those which are temperature stable above ~ 300 Deg F.There are two key prerequisites to formulating a desirable HTHP WBM; Rheology and tight Fluid loss control. Rheology can be quite easily be controlled with the use of bentonite or other viscosifying natural ( Attapulgite, sepiolite) or synthetically produced clay minerals (Hectorite, Laponite). The HTHP fluid loss control, is the main problem and is more often than not difficult to optimise in the laboratory. Invariably, it is necessary to have several fluid loss additives in a formulation to synergistically lower the HTHP fluid loss.

A EQUIPMENT

a) Balance: precision ± 0.1 gb) Hamilton beach mixer and cupc) Weighing boatsd) Spatulae) pH meter: precision ± 0.1 pH

B. ORDER OF ADDITION

1. Prehydrated bentonite (as described in DF/EAF/001)2. Fresh water or seawater3. Salts3. Black Powders4. Caustic soda5. Polymeric Additives6. Weighting agent7. Dispersants6. Simulated drilled solids

C. PROCEDURE

1. Add the required weight of prehydrated bentonite followed by the required amount of water and salts to a Hamilton beach cup. Mix for 5 minutes on low speed (11,000 rpm ± 300 rpm) and adjust the pH as required with caustic soda.

2. Add black powders (gilsonite, asphaltics, lignites etc.) slowly into the vortex over a one minute period, ensuring that all the powder has completely dispersed. Mix for a further 4 minutes

3. Adjust pH of fluid to appropriate value over a 5 minute period

4. Add polymeric additives slowly into the vortex over a five minute period, ensuring that all polymer has completely dispersed and that none adheres to the sides of the mixing vessel or the mixer shaft. Mix for a further 5 minutes.


6. Add the dispersants (E.g.. IDTHIN 500, IDSPERSE XT) slowly into the vortex over a 1 minute period. Mix for a further 4 minutes.



8. Continue to mix the whole mud for the remaining time in the hour i.e. 9 minutes

9. Cover and allow to stand for 1 hour before testing to allow the fluid to equilibrate and any entrained air to escape.


Safety Notes :

a. Adjusting pH

(i) Unless the quantity of caustic soda is defined in the formulation, it is recommended that w/w caustic soda solution (e.g. 50% w/w) be used for pH adjustment. Use drop wise from dropper bottle

(ii) Disposable plastic gloves and safety glasses are to be worn at all times, when handling caustic soda (solid or solution).

(iii) Prevent splashes - but if any occur mop up immediately.

(iv) When measuring pH, hold the pH probe against side of "cup". Do not allow it to touch the rotating shaft.

Procedural notes :

∑ Ensure temperature of fluid does not exceed 150 0F during the mixing process.

∑ It stands to reason, that most HTHP formulations will be intermediate (12 -15ppg) to high (> 15 ppg) mud weights to control formation pressures. The barite loading in the fluid will therefore be significant. Barite quality can have very large effects on mud properties, especially at high mud weights. It is important to recognise that two barites that pass API specifications can produce muds with very different properties.

When formulating muds for a customer's or independent laboratory to reproduce, it is important to ensure that the same stock of barite is used by both laboratories in order to achieve reproducible results. This is also the case when trying to reproduce the properties of a field mud: if possible, a sample of the rig barite should be obtained.

∑ If excessive foaming occurs during mixing, then dropwise addition of a defoamer may be added to alleviate the situation.



SUMMARISED MIXING PROCEDURE FOR HIGH TEMPERATURE WATER-BASED MUDS

ORDER OF ADDITION



Mix time (mins)


Prehydrated Gel 0 - 5 Non-Treated BentoniteSalts 5 1 9 KCl, NaClBlack Powders 15 1 4 Calotemp, Soltex, Driscal D, Hi

-Temp,pH Adjustment 20 5 - 50 % NaOH or KOHPolymeric additives 25 5 5 Caloflo 100, Polytemp,

Polydrill, Hi - temp IIWeighting agent 35 1 - 2 8 - 9 Barite, Micromax, HaematiteDispersant 45 1 4 Idthin 500, Idperse XTDrilled Solids 50 1 9 Rev Dust, OCMA, Hymod

Prima


3.3.3 PROCEDURE DF/EAF/005 -Oil and Synthetic Based Muds (350 ml - 1 Lab Barrel)

This procedure is generally applicable for the following drilling fluid systems;TRUDRILLINTERDRILLULTIDRILL

Oil based muds are extremely sensitive to shear history. Unlike WBM’s they require a critical amount of shear to develop the properties completely.

A EQUIPMENT

a) Balance: precision ± 0.1 gb) Hamilton beach mixer and cupc) Weighing boatsd) Spatula

B. ORDER OF ADDITION (unless otherwise requested)

1. Base Oil2. Primary Emulsifiers E.g. TRUMUL and EMUL3. Secondary Emulsifiers E.g. TRUSPERSE and FW4. Organophillic Clay E.g. VISTONE and TRUVIS5. Organo-polymers E.g. TRUFLO 1006. Black powders E.g. INTERDRILL S, SOLTEX, TRUDRILL S7. Lime 8. Brine9. Weighting agent10. Simulated drilled solids

C. PROCEDURE

1. Place a Hamilton Beach cup on a balance. Add the required weight of Base oil to a Hamilton beach cup. Add the required weight of primary and secondary emulsifiers slowly using a syringe to the cup. Add the lime. Mix for 5 minutes on low speed (11,000 rpm ± 300 rpm) .

2. Add the organophillic clay slowly into the vortex over a 1 minute period, ensuring that all the clay has completely dispersed and that none adheres to the sides of the mixing vessel or the mixer shaft. Mix for a further 4 minutes.

3. Add polymeric additives slowly into the vortex over a 1 minute period. Mix for a further 4 minutes.

3. Add black powders (gilsonite, asphaltics, lignites etc.) slowly into the vortex over a 1 minute period, ensuring that all the powder has completely dispersed. Mix for a further 4 minutes

4. Add the brine phase (usually pre-dissolved calcium chloride in water) slowly into the vortex over a 2 minute period. Mix for a further 8 minutes.



8. Continue to mix the whole mud for the remaining time in the hour.


9. Cover and allow to stand for 30 minutes before testing to allow the fluid to equilibrate and any entrained air to escape.


Safety Notes :

(i) The mixing of fluids should be carried out in an enclosed mixing room, if possible, ensuring that the extraction system is operating.

(ii) When testing base oils having flash points of 70°C or lower, the mixing temperature must be controlled at least 10°C lower than the flash point. Mixing of muds using crude oil with low flash points (< 20°C) is not allowed by this method.

Procedural notes :

∑ Ensure temperature of fluid does not exceed 150 0F during the mixing process.


SUMMARISED MIXING PROCEDURE FOR OIL AND SYNTHETIC BASED MUDS

ORDER OF ADDITION



Mix time (mins)


Base Oil 0 - - HDF 200, Ultidrill, dieselEmulsifiers/ wetting agents

0 1 4 Emul, Emul HT, Trumul, O/W, Trusperse, FL

Organophillic Clay 5 1 4 Truvis, VistonePolymeric additives 10 1 4 Truflo 100, Alcomer , DovamulBlack Powders 15 1 4 Trudrill S, Interdrill S, Soltex,

Gilsonite, LignitesLime 20 1 4 LimeBrine 25 2 8 CaCl2Weighting agent 35 2 8 Barite, Micromax, HaematiteDrilled Solids 45 1 19 Rev Dust, OCMA, Hymod

Prima


4 ROUTINE TESTING PROCEDURES

4.1 INTRODUCTION

The mud testing procedures used by Dowell are based on the API Recommended Practice 13B-1 First Edition 1st June 1995, for Standard Testing Procedures for Water Based Drilling fluids and API Recommended Practice 13B-2 Second Edition, 1st December 1995, for Standard Testing procedures for Oil based Drilling Fluids and API Recommended Practice 13J First Edition 1986, for Testing of Heavy Brines.

API publications can be obtained from;

API Publications Department1220 L Street NW,Washington, DC 20005 - USA fax : (1) 202 682 8537

4.2 API REFERENCES

(i) Tests applicable to both OBM and WBM - API recommended practices.

1. Mud weight (density) RP 13B-1 Page 5-8RP 13B-2 Page 5-8

2. Viscosity and gel strength RP 13B-1 Page 9-11RP 13B-2 Page 9-12

3. Filtration LTLP RP 13B-1 Page 12-13RP 13B-2 Page 11-12

3. Filtration HTHP RP 13B-1 Page 13-15RP 13B-2 Page 13-14

4. Water, oil and solids RP 13B-1 Page 16-18RP 13B-2 Page 15-18

5. Shear strength measurement RP 13B-1 Using Shearometer tube RP 13B-2 Page 28

(ii) Tests specific to WBM - API recommended practices

1. Sand RP 13B-1 Page 192. Methylene blue capacity RP 13B-1 Page 20-213. pH RP 13B-1 Page 22-234. Chemical analysis

4.1 Alkalinity and lime content RP 13B-1 Page 24-264.2 Chloride content RP 13B-1 Page 264.3 Total hardness RP 13B-1 Page 26-274.4 Calcium RP 13B-1 Page 284.5 Magnesium RP 13B-1 Page 294.6 Formaldehyde RP 13B-1 Page 29-304.7 Sulphide RP 13B-1 Page 30-334.8 Carbonate RP 13B-1 Page 33-354.9 Potassium > 5000 mg/l RP 13B-1 Page 35-374.10 Potassium < 5000 mg/l RP 13B-1 Page 37-38

5. Resistivity RP 13B-1 Page 40

(iii) Tests specific to OBM - API recommended practices

1. Chemical analysis of OBM Page 191.1 Alkalinity of whole mud RP 13B-2 Page 19-201.2 Whole mud chlorides RP 13B-2 Page 201.3 Whole mud calcium RP 13B-2 Page 20

2. Electrical stability RP 13B-2 Page 21-22

(iv) Additional procedures - API recommended practices


1. Removal of air or gas from RP 13B-1 Page 41 Mud prior to testing RP 13B-2 Page 432. Sampling, Inspection and RP 13B-1 Page 44 Rejection RP 13B-2 Page 443. Rig site sampling RP 13B-1 Page 45

RP 13B 2 Page 454. Drill pipe corrosion ring coupons RP 13B-1 Page 42-43


4.3 PHYSICAL TESTING

4.3.1 PROCEDURE DFT/EAF/001 - Mud Weight Determination

The Mud Balance is used for mud weight determinations and is the recommended equipment ii the API 13B standard procedures for testing drilling fluids. The mud balance is accurate to within +/- 0,1 lb/gal ( or 0.5 lb/cu.ft, 0.01 g/ml , 10 g/l). It is designed such that the mud cup, at one end of the beam, is balanced by a fixed counterweight at the other end, with a sliding weight rider free to move along the graduated scale. A level bubble is mounted on the beam to allow accurate balancing.

A EQUIPMENT

Standard Mud BalancePressurised Mud Balance

B PROCEDURE - Standard Mud Balance

1. Instrument base must be set on a flat level surface

2. Measure and record the mud temperature

3. Fill the mud cup with the mud to be tested

4. Replace cap until it is firmly seated, insuring some of the mud is expelled through the hole on top, to free any trapped gas.

5. Holding cap firmly on mud cap ( with cap hole covered ) wipe the outside of the cup until it is clean and dry.

6. Place the beam on the base support and balance it by using the rider along the graduated scale. Balance is achieved when the bubble is directly under the centre line.

C PROCEDURE - Pressurised Mud Balance

A problem with many drilling fluids is that they contain considerable amounts of entrained gas, leading to inaccurate mud weight measurements on the standard mud balance. By pressurising the mud cup the entrained air volume can be decreased to a minimum. The balance operates in much the same way as standard mud balance except the lid of the mud cup has a check valve.

1. Follow steps 1 - 5 as for the standard mud balance procedure

2. When the lid has been placed on the cup, pull the check valve up in the open position, wipe the outside of the cup clean and dry.

3. The pressurising plunger is similar to operating a syringe. The plunger is filled by submersing the nose of the plunger in the drilling fluid with the piston rod in the completely inward position. The piston rod is then drawn up, thereby filling the plunger with fluid.

4. The nose of the plunger is then placed into the female 'O' ring on top of the cap. The sample is pressurised by maintaining a downward force on the cylinder housing in order to hold the check valve open, whilst at the same time forcing the piston rod inwards. Approximately 50 pounds of force or greater should be maintained on the piston rod.


5. The check valve in the lid is pressure actuated, i.e. closing when a pressure is applied. The valve is therefore closed by gradually easing up on the cylinder housing while maintaining pressure on the piston rod.

6. Once the check valve is closed, disconnect the plunger and weigh the fluid as in step 6 of the standard mud balance procedure.

Procedural notes :

∑ Ensure fluid is at room temperature ( 77 deg F) prior to testing.


4.3.2 PROCEDURE DFT/EAF/002 - Viscosity and Gel Strength

Drilling fluid is contained in the annular space between two concentric cylinders. The outer cylinder or rotor sleeve is driven at a constant rotational velocity. The rotation of the rotor sleeve in the fluid produces a torque on the inner cylinder or bob, and the dial attached to the bob indicates displacement of the bob. This is the standard procedure recommended by API 13B for field testing water based drilling fluids.

Instrument constants have been adjusted so that the Bingham plastic viscosity and yield point can be obtained by using the readings at 300 rpm and 600 rpm.

A EQUIPMENT

a) Fann 35, 110 volt, powered by a two speed synchronous motor to obtain speeds of 3, 6, 100, 200, 300 and 600.

b) Mud cupc) Stopwatch

d) Thermometer 32 - 220 0F

B PROCEDURE

1. Pour mud sample into sample cup until it reaches the level line.

2. Locate sample cup in viscometer stand using the 3 locating pins on the bottom.

3. Record the temperature of the mud sample

4. Immerse bob and rotor sleeve into the mud until it reaches the scribed level on the rotor sleeve ( just over the two holes ) by raising the viscometer stand.

5. Turn on viscometer at mains and ensure the gear knob on top of instrument is pushed completely down and that switch located to the back right is pushed away from the operator. The rotor sleeve should now be rotating at 300 rpm in the mud sample. Wait for temperature to increase and settle at 120 Deg F before measuring the rheology.

6. Pull switch at back right towards the operator. The rotor sleeve should now be rotating at 600 rpm in the mud sample. Wait for dial reading to settle before taking the reading.

.7. Push switch located to the back right away from the operator to change rpm to 300

and record the dial reading as above.

8. For a more extensive rheogram the torque at rpm's 100 and 200 can also be measured by pulling the gear knob completely upwards.

9. Stir mud at high speed for 10 seconds and then allow to stand for 10 seconds. Rotate at 3 rpm and record the reading on the dial; this is the 10 second or initial gel strength.

10. Re-stir the mud for 10 seconds and then allow to stand for 10 minutes. Rotate at 3 rpm and record the reading on the dial; this is the 10 minute gel strength.

11. Re-stir the mud for 10 seconds and then allow to stand for 30 minutes. Rotate at 3 rpm and record the reading on the dial; this is the 30 minute gel strength.

12. Dispose of waste mud in container provided in the Drilling Fluids Laboratory. Wash and dry the sample cup, bob, and rotor sleeve immediately after use.

NOTE: All gel strength readings are reported in lb/ 100 sq.ft or Pa


C CALCULATION

Plastic Viscosity (PV) = 600 rpm reading - 300 rpm reading Centipoises (cP)

Yield Point (YP) (lb/100 ft2) = 300 rpm reading - Plastic Viscosity

Apparent Viscosity = 600 rpm reading / 2Centipoises (cP)

Yield Stress (YS) = (2 * 3 rpm reading) - 6 rpm reading

Power Law Index (n) = 3.32 log (600 reading / 300 reading)

Consistency Index (K) (lb/100 ft2) = 600 reading / 1022n

Note: If the 600 rpm reading is off scale then the PV and YP can be calculated as follows;

YP = ( 2 x 100 rpm reading) - 200 rpm reading

PV = 300 rpm reading - YP


4.3.3 PROCEDURE DFT/EAF/003 - Low Temperature/Low Pressure Filtration

The low pressure filter press is a static filtration procedure recommended by the API 13B standard procedures for testing drilling fluids.

A OPERATING PARAMETERS

100 psi Nitrogen for 30 minutes

B EQUIPMENT

a) Filtration Cell - Diameter 3” x Height 2.5”b) OFI specially Hardened Filter paper - Filtration Area 7.07 sq.in (Alternatively - Whatman

No 50 paper)c) Low Pressure Nitrogen supply (100 psi)d) Stop Clocke) 10 and 25 ml measuring cylinders

C PROCEDURE FOR FANN 128L, IN-SERIES FILTER PRESS

1. Invert filtration cup and place finger over nozzle whilst filling cup with mud. Fill cup to 3/4 full.

2. Insert neoprene 'O' ring (1/16") until seated tightly.

3. Insert filter paper on top of 'O' ring

4. Tighten lid by seating and twisting through 90 ° and hand tightening screw. 5. Invert cell and place filtration cell in mounting assembly

6. Place graduated measuring cylinder under drain tube to receive filtrate. Close the relief valve by pushing inwards and adjust regulator so that a pressure of 100 psi (+/- 5 psi ) is obtained.

7. Open valve and start stop clock.

8. At the end of 30 minutes close valve and measure the filtrate volume in mls (cc's) per 30 minutes as the API filtrate, and the initial mud temperature in degrees F at the start of the test.

9. SAVE the filtrate when required, for ionic analysis by FIM and/or titration techniques.

10. Disassemble the cell, discard mud into mud waste container only (located in Drilling Fluids Lab). Save filter paper handling with care and wash filter cake with a gentle stream of distilled water.

11. Measure and report the thickness of the cake to the nearest 1/32" (0.8 mm). Report any other observations, such as texture, colour, hardness, compressibility, flexibility etc.

D CALCULATION

API FLUID LOSS = 30 min ReadingRELATIVE API FLUID LOSS * = (30 min Reading - 7.5 min reading ) x 2SPURT LOSS = API FLUID LOSS - RELATIVE API FLUID LOSS

* Relative API Fluid Loss is corrected for spurt loss prior to cake formation


4.3.4 PROCEDURE DFT/EAF/004 - High Temperature/High Pressure Filtration

The high pressure / high temperature filter press is a static filtration procedure recommended by the API 13B standard procedures for testing drilling fluids at elevated temperatures and pressures.

A OPERATING PARAMETERS

500 psi differential pressure Nitrogen for 30 minutes at a temperature of 300 degrees F, or as specified by an operator.

B EQUIPMENT

a) HTHP Filtration Cell - Diameter 3” x Height 3.0”b) OFI specially Hardened Filter paper - Diameter 2.5” / Filtration Area 4.91 sq.in c) High Pressure Nitrogen supply (600 psi)d) Stop Clocke) 10 and 25 ml measuring cylinders

C PROCEDURE

1. Turn on heated jacket at the mains and insert a thermometer into the jacket and leave to preheat.

2. With stem valve closed on bottom of cell, fill up cell with mud to within 0.5" of the 'O' ring groove, to allow for thermal expansion.

3. Insert filter paper into the cell followed by the bottom cell plate assembly over the filter paper and twist to align with the safety locking lugs. Tighten grub screws evenly using the Allan key provided.

4. Ensure all stem valves are tightly closed.

5. Invert cell and place in filtration mounted heated jacket assembly. Insert a thermometer into the HPHT cell.

6. Place the pressure unit on top valve and lock into place using a locking pin Lock the bottom pressure unit to the bottom valve into place, again ensuring that locking pin is inserted.

7. Apply 100 psi to both ends of the HPHT cell with the valves still closed. 8. Open the top valve to apply 100 psi to the mud while heating to prevent the mud from

boiling prior to reaching the target temperature. The time for heating the mud sample to the target temperature should not exceed 60 minutes.

9. Once the sample has reached the desired temperature, increase the pressure of the top pressure unit to 600 psi.

10. Open the bottom valve and start the stop-clock to start filtration experiment.

11. Collect the filtrate for 30 minutes maintaining the temperature to within +/- 5 degrees F.

12. If the back pressure rises above 100 psi during the test, cautiously reduce the pressure by drawing off a portion of the filtrate from the bottom of the receiving vessel.


13. Once the test has finished close the top and bottom valves and shut off the pressure supply from the regulators. Bleed the lines using the relief valves provided.

14. Allow filtrate to cool for 30 minutes and then draw off into a graduated 20 ml measuring cylinder and read volume. When filtering water-based muds, one can SAVE the filtrate for ionic analysis.

15. CAUTION - the cell still contains 500 psi pressure, so cool cell to room temperature in a water bath and then bleed off the pressure slowly by opening the valves.

16. Disassemble the cell, discard mud into mud waste container only. Save filter paper handling with care and wash filter cake with a gentle stream of distilled water or base oil.

17. Measure and report the thickness of the cake to the nearest 1/32" (0.8 mm). Report any other observations, such as texture, colour, hardness, flexibility etc.


4.3.5 PROCEDURE DFT/EAF/005 - Retort - Water, Oil and Solids

A retort is used to determine the quantity of liquids and solids in a drilling fluid. A carefully measured sample of mud is placed in a steel cell and then heated until it vaporises. The vapours are then passed through a condenser and collected in a calibrated cylinder. The volume of liquid, water and oil can then be calculated in percent. The percent solids, both suspended and dissolved, is determined by subtraction of the total liquid from 100%.

A EQUIPMENT

Three retort sizes are available in the Drilling Fluids Laboratory, 10 ml, 20 ml and 50 ml. The latter is the most commonly used due to its greater precision and accuracy. Each unit consists of a;

a) Sample cupb) Thermostatically controlled heating elementc) Liquid condenserd) Pyrex measuring cylinder (50 ml)e) Fine steel woolf) Pipe cleanerg) High temperature silicone greaseh) Defoaming agenti Spatula

B PROCEDURE

1. A homogeneous sample of de-aerated mud which has cooled to approximately 80°F is added to a clean, dry, calibrated retort cup (50 ml).

2. The void space above the calibrated retort cup is filled with steel wool.

3. The retort is then sealed, the condenser attached and the equipment placed into the heating jacket.

4. A graduated measuring cylinder is put underneath the condenser discharge.

5. The retort heater is switched on and heating is continued until 10 minutes beyond the point at which no more vapour droplets fall from the condenser.

6. The volume of oil and water collected is noted and the percent oil, water and solids present in the sample calculated.

7. The equipment is allowed to cool and solids removed from the retort cup by means of a spatula, excess oil residue can be removed using lengths of pipe cleaners.

C CALCULATION

Volume % water (Vw) = (ml H2O / ml sample) x 100Volume % oil (Vo) = (ml Oil / ml sample) x 100Volume % solids (Vs) = 100 - [Vw+ Vo]

Average SG of Solids = (Mud SG x 100) - ( Vw+ Vo ) Vs

The volume % solids includes both suspended solids and dissolved materials (e.g. salt). Suspended solids are weighting materials and other low gravity solids such as mud additives and cuttings


4.3.6 PROCEDURE DFT/EAF/006 - Sand Content

The sand content apparatus consists essentially of a 200 mesh sieve, a funnel and a glass measuring tube calibrated to read the percentage of particles larger than 74 microns in the mud.

A PROCEDURE

1. Fill the tube with mud to the mark labelled “Mud to Here”, then add base fluid to the mark “Base Fluid to Here”. Cover the mouth of the tube with the thumb and shake the tube vigorously.

2. Pour the suspension through the clean, dry mesh screen, being careful to remove all solids out of the tube by flushing with base fluid back through the same mesh screen. By tapping the side of the screen the pouring of the mud through the screen may be facilitated. The material retained on the screen should not be manually pushed through as this will give erroneous results and may also damage the sieve itself. Wash the sand retained on the screen with a stream of base fluid.

3. Fit the funnel upside down over the top of the sieve, invert slowly turning the tip of the funnel into the mouth of the tube and wash the sand back into the tube with some clean base. Allow the sand to settle.

4. Record the quantity of sand settled in the graduated tube as the sand content of the mud in percent by volume.

5. Wash the apparatus thoroughly after use.


4.4 CHEMICAL TESTING

Chemical analysis of the aqueous phase of a drilling fluid is of paramount importance in understanding the stability of the fluid, its tolerance to contaminants and allows a geochemical insight into the reactivity of the lithologies being drilled. Complex equilibria exist within aqueous systems that if perturbed can have either a positive or negative affect on the overall properties of the fluid.

4.4.1 PROCEDURE DFT/EAF/007 - pH - H +and OH -

Field measurement of drilling fluid (or filtrate) pH and adjustments to the pH are fundamental to controlling water-based drilling fluid properties.

pH expresses acidity or alkalinity of an aqueous solution. An acid can be defined as a substance which dissociates in aqueous solution to give hydrogen [H+] ions, whilst a base or alkali gives [OH-] ions. The term “pH” denotes the negative logarithm of the hydrogen ion, [H+] , activity in aqueous solutions (activity and concentration are equal only in dilute solutions).

The recommended method for pH measurement is with a glass electrode pH meter. This method is accurate and reliable, being free of interferences if a high quality electrode system is used with a properly designed instrument. Rugged pH instruments are available that automatically temperature compensate the slope and are preferred over the manually adjusted instruments.

Note: Colour matching pH paper and sticks are used for field measurements, but are not recommended as they are only reliable in very simple water base muds. Mud solids, dissolved salts and chemicals, and dark coloured liquids cause serious errors in pH paper values. Readability is normally about 0.5 pH units.

A EQUIPMENT

a) pH Meter: millivolt range potentiometer calibrated to show pH units for measuring the potential between a glass membrane electrode and a standard “reference” electrode.

b) Electrode system: A combination system of a glass electrode for sensing [H+] ions and a standard voltage reference electrode (silver/silver chloride), constructed as a single electrode.

c) Buffer solutions: Three solutions to calibrate and set the slope of the pH meter prior to sample measurement.

1.) pH = 4.0: potassium hydrogen phthalate at 0.05 molar in water. Gives 4.01 pH at 75°F.

2.) pH = 7.0: Potassium dihydrogen phosphate at 0.02066 molar and disodium hydrogen phosphate at 0.02934 molar in water. Gives 7.00 pH at 75°F.

3.) pH = 10.0: sodium carbonate at 0.025 molar and sodium bicarbonate at 0.025 molar in water. Gives 10.01 pH at 75°F.

Note: The shelf life of all buffers should not exceed six months before disposal. Date of preparation of the buffer should be shown on bottles used in the field. Bottles should be kept tightly stoppered.

d) Distilled or deionised water: in spray bottle.

e) Soft tissues: to blot electrodes.

f) Thermometer: glass, 32-220°F (0-105°C).


4.4.2 PROCEDURE DFT/EAF/008 - Alkalinity - HCO3-, CO3

—and OH-

Alkalinity can be considered as the acid-neutralising power of a substance. Alkalinity measurements can be made on either the whole mud (designated with the subscript m) or on the filtrate (subscript f). The data collected can also be used to estimate the concentrations of hydroxyl (OH-), carbonate (CO3

-2) and bicarbonate (HCO3-) ions in the drilling fluid.

Knowledge of the mud and filtrate alkalinity is essential to ensure proper control of mud chemistry. Mud additives, particularly some deflocculants, require an alkaline environment to function properly. The source and nature of the alkalinity is often as important as the fact that some alkalinity exists. Alkalinity arising from hydroxyl ions is generally accepted as being beneficial, while alkalinity resulting from carbonates and/or bicarbonates may have adverse effects on mud performance and stability.

e.g.

Hydroxyl ions Mud stable and in good conditionHydroxyl + Carbonate Stable and in good conditionCarbonate Unstable but can be controlledCarbonate + bicarbonate Stable but difficult to controlBicarbonate Unstable and very difficult to control

A EQUIPMENT

a.) Sulphuric acid solution: standardised 0.02 Normal (N/50)

b.) Phenolphthalein indicator solution: 1 g dissolved in 60 c.c. ethyl or methyl alcohol made up to 100 c.c. with distilled water.

c.) Methyl Orange Indicator solution: 0.2 g dissolved in 100 c.c. distilled water.

d.) Bromophenol Blue: 0.02 g in 100 c.c. distilled water (instead of methyl orange for dark filtrates.

e.) pH meter: optional, but is more accurate than indicator solution.

f.) Titration vessel: 100-150 c.c. preferably white.

g.) Volumetric pipettes: 1 c.c.

h.) Graduated pipettes: one 1 c.c. and one 10 c.c.

i.) Hypodermic syringe: 2.5 c.c.

j.) Distilled water free of carbon dioxide (by boiling)

k.) Stirring rod.

B PROCEDURE - Filtrate Alkalinity: Pf, Mf

1. Measure one or more c.c. of filtrate to the titration vessel.

2. Add two or more drops of phenolphthalein indicator solution. If the indicator turns pink, add 0.02N sulphuric acid, drop by drop from the pipette, while stirring, until the pink colour disappears. If the sample is so coloured that the indicator colour change is masked, the endpoint can be taken when the pH drops to 8.3, as measured with a pH meter.


3. Report the phenolphthalein alkalinity of the filtrate, Pf, as the number of c.c. of 0.02N acid required per c.c. of filtrate.

4. To the sample which has been titrated to the Pf end point, add two or three drops of methyl orange indicator changes from orange to pink. Add 0.02N sulphuric acid, drop by drop from the pipette, while stirring, until the pink colour disappears. The endpoint can also be taken when the pH of the sample drops to 4.3 as measured by a pH meter.

5. Report the methyl orange alkalinity of the filtrate, Mf as the total c.c. of 0.02 N acid per c.c. of filtrate required to reach the methyl orange end point (including that amount for the Pf endpoint).

C PROCEDURE - Mud Alkalinity: Pm

1. Measure 1.0 c.c. of mud into the titration vessel using a syringe. Dilute that mud sample with 25-50 c.c. of distilled water (free of carbon dioxide by boiling).

2. Add 4-5 drops of phenolphthalein indicator solution and, while stirring, titrate rapidly with 0.02 N standard sulphuric acid until the pink colour disappears. If the endpoint colour change cannot be seen, it can be taken when the pH drops to 8.3 using a pH meter.

3. Report the phenolphthalein alkalinity of the mud, Pm, as the number of c.c. acid required per c.c. of mud.


4.4.3 PROCEDURE DFT/EAF/009 - Chloride Determination

This standard method (Mohr’s method) consists of titrating all chlorides present in the filtrate and expressing the result in terms of sodium chloride. This explains why in some cases, for example in the presence of calcium and magnesium chlorides, the result obtained (expressed in NaCl), can give concentrations greater than the solubility of NaCl. The chlorides are precipitated in the form of silver chloride, in the presence of an indicator, potassium chromate. The reaction occurs in two steps:

Cl- + AgNO3 ◊ AgCl (white precipitate) + NO3-

CrO42- + 2Ag+ ◊ Ag2CrO4 (orange-red precipitate)

The end point is detected with Potassium Chromate.The excess Ag+ ions present after all the Cl- ions have been removed from solution, react with chromate to form silver chromate, an orange-red precipitate. Since AgCl is less soluble than Ag2 CrO4 the latter cannot form permanently in the mixture until the precipitation of AgCl has reduced the Cl- to a very small value.

Note: This titration must be carried out in a neutral medium because; in an acid medium the silver chromate dissolves, and in an alkaline medium silver oxide or silver carbonate precipitate. In practice, as the filtrate is neutral or alkaline, it is first acidified with nitric acid, then neutralised with calcium carbonate. The addition of the nitric acid has the advantage of discolouring the filtrate (partially).

A EQUIPMENT

a) Silver nitrate solution: 4.7910 g/l (0.0282 N or equivalent to 0.001 g chloride ion/c.c.). Store in amber or opaque bottle.

b) Potassium Chromate Indicator solution: 5 g/100 c.c. water.

c) Sulphuric or nitric acid: standardised 0.02 N (N/50)

d) Phenolphthalein indicator solution: 1 g/100 c.c. of 60% alcohol in water solution.

e) Calcium Carbonate: precipitated, chemically pure grade.

f) Distilled water: free of carbon dioxide by boiling.

g) Graduated pipettes: one 1 c.c. and One 1-c.c.

h) Titration vessel: 100-150 c.c. preferably white.

i) Stirring rod.

B PROCEDURE

1. Add one or more c.c. of filtrate to the titration vessel. Add 2-3 drops of phenolphthalein solution. If the indicator turns pink, add acid drop by drop, while stirring, until the colour disappears. If the filtrate is deeply coloured, add an additional 2 mL of acid and stir. Then add 1 g of calcium carbonate and stir (or until effervescence stops).

2. Add 25-30 c.c. distilled water and 5-10 drops potassium chromate. Stir while adding silver nitrate solution drop by drop, until the colour changes from yellow to orange-red and persists for 30 seconds. Record the number of mL silver nitrate solution required to reach the endpoint.


Note: If the chloride ion concentration exceeds 10,000 mg/l, use 0.282 N silver nitrate solution equivalent to 0.01 g/c.c. The factor 1,000 is then changed to 10,000.

C CALCULATION

Report the chloride ion concentration of the filtrate in mg/l, calculated as follows:

Chloride, (mg/l) = 1000 x (0.0282 N silver nitrate, mL) filtrate sample mL

Or when using 0.282 N silver nitrate

Chloride, (mg/l) = 10000 x (0.282 N silver nitrate, mL) filtrate sample mL

To convert units:

Chloride, (ppm) = (Chloride, mg/l) ___Specific gravity of filtrate

Salt (NaCl), mg/l = (1.65) x (Chloride, mg/l).


4.4.4 PROCEDURE DFT/EAF/010 - Total Hardness Determination

The hardness of water or mud filtrate is due primarily to the presence of calcium and magnesium ions. Divalent cations such as these tend to have a detrimental affect on clay and polymer based drilling fluid additives and systems. For this reason hardness is typically kept to a minimum and close monitoring of their aqueous concentrations is required.

When EDTA (sodium salt of ethylene-diaminetetracetic acid) is added to aqueous solutions containing calcium and/or magnesium, it combines to form a complex whose end-point is determined by a suitable indicator.

EDTA-Na + Ca++ + Mg++ -------> EDTA- Ca + EDTA- Mg + Na+

A EQUIPMENT

a) 0.02 N EDTA (0.01 M)

b) Ammonia Buffer* in dropper bottle

c) Manver Indicator (solution or crystals)

d) Masking agent**: 1:1:2 mixture by volume of triethanolamine : tetraethylenepentamine : water

e) Deionised water: free of carbon dioxide by boiling.

f) Graduated pipettes: one 1 mL, 2 mL and 5 mL

g) Titration vessel: 100-150 c.c. preferably white.

h) Stirring rod.

* Ammonia buffer = 54 g Ammonium chloride and 400 mL Ammonium Hydroxide (15 N) made up to 1000 mL with deionised water.

** 1mL of Masking agent should be added if soluble iron is suspected to be present.

B PROCEDURE

1. Add one or more c.c. of filtrate to the titration vessel. Dilute with approximately 50 mL of deionised water. Add 4 drops of Ammonia buffer and 2 drops (or crystals) of manver indicator. A wine red colour will develop if either calcium or magnesium ions are present.

2. Stir while adding EDTA solution drop by drop, until the colour changes from red to blue and persists for 30 seconds. Record the number of mL EDTA solution required to reach the endpoint.

C CALCULATION

Report the Total Hardness as calcium ion concentration of the filtrate in mg/l, calculated as follows:

Total Hardness as calcium, (mg/l) = 400 x (0.02 N EDTA, mL) filtrate sample mL

Total Hardness as CaCO3, (mg/l) = 1000x (0.02 N EDTA, mL) filtrate sample mL


4.4.5 PROCEDURE DFT/EAF/011 - Calcium Hardness Determination

This method allows the selective determination of calcium ions in aqueous solutions.

When EDTA (sodium salt of ethylene-diaminetetracetic acid) is added to aqueous solutions containing calcium and/or magnesium, it combines to form a complex whose end-point is determined by a suitable indicator.

EDTA-Na + Ca++ -------> EDTA- Ca + Na+

A EQUIPMENT

a) 0.02 N EDTA

b) 8N Potassium Hydroxide Buffer (KOH)

c) Calver II Indicator (crystals)

d) Masking agent*: 1:1:2 mixture by volume of triethanolamine : tetraethylenepentamine : water

e) Deionised water: free of carbon dioxide by boiling.

f) Graduated pipettes: one 1 mL, 2 mL and 5 mL

g) Titration vessel: 100-150 c.c. preferably white.

h) Stirring rod.

* 1mL of Masking agent should be added if soluble iron is suspected to be present.

B PROCEDURE

1. Add one or more c.c. of filtrate to the titration vessel. Dilute with approximately 50 mL of deionised water. Add 2 drops of KOH buffer and several grains of Calver II indicator. Swirl to mix. A wine red colour will develop if calcium ions are present.

2. Stir while adding EDTA solution drop by drop, until the colour changes from red to blue and persists for 30 seconds. Record the number of mL EDTA solution required to reach the endpoint.

C CALCULATION

Report the Total Hardness as calcium ion concentration of the filtrate in mg/l, calculated as follows:

Total Hardness as calcium, (mg/l) = 400 x (0.02 N EDTA, mL) filtrate sample mL

Total Hardness as CaCO3, (mg/l) = 1000x (0.02 N EDTA, mL) filtrate sample mL

Note: The magnesium hardness = Total Hardness - Calcium Hardness


4.4.6 PROCEDURE DFT/EAF/012 - Soluble Carbonates Determination

The concentration of soluble carbonates in a drilling fluid filtrate can be determined more accurately and with less interference’s with a gas train than by those measurements involving alkalinity. Total soluble carbonates include CO2 and the carbonate (CO3

2-) and bicarbonate (HC03

-) ions.

Mud filtrate is acidified in a Garrett Gas Train, converting all carbonates to CO2, which is then evolved by bubbling an inert carrier gas through the sample. The Gas Train separates the gas from the liquid, and the gas stream is collected in a one litre gas bag (to allow CO2 to mix uniformly) and subsequently drawn through a Drager tube at a fixed flow rate. The Drager tube responds to CO2 by progressively staining purple along its length. A reaction between CO2 and a hydrazine chemical causes a crystal violet indicator to turn purple. The stain length is proportional to the total carbonate in the filtrate.

A EQUIPMENT

The following materials are required to perform the analysis of total soluble carbonates using a solids-free filtrate sample.

a) Garrett Gas Train: consisting of a transparent plastic gas train, an inert gas supply (N2 or N2O) with pressure regulator, a floating ball flowmeter and a Drager tube.

b) Flexible tubing: Type inert to carbon dioxide

c) Drager CO2 Analysis Tube: marked CO2 0.01 %/a - (No. CH-308-01)

d) Drager One litre Alcotest Gas Bag: (No 7626425)

e) Drager Multigas Detector Hand Operated Vacuum Pump, Model 31

f) Stopcock: (2-way bore): 8 mm glass with Teflon plug.

g) Sulphuric Acid: approximately 5N, reagent grade.

h) Hypodermic syringes: one 10 c.c. (for acid), and one each 10 cc, 2.5 cc and 1.0 cc (for sample).

i) Hypodermic needles: two 1.5 inch (38 mm) with 21 gauge needles.

j) Octanol defoamer in a dropper bottle.

k) Inert Carrier Gas: Nitrogen (N2) bottle with low pressure regulator (preferred), or Nitrous oxide (N20) cartridges.

Note: Nitrogen is preferred over nitrous oxide as the carrier gas. Because nitrous oxide cools upon expansion and chills the diaphragm in the regulator, prolonged flow will cause the regulator to perform erratically,

B PROCEDURE

1. Make sure the gas train is clean, dry and on a level surface, with the top removed.Note: If carbon dioxide has been used as the carrier gas in the previous test (i.e. sulphide

analysis) the regulator, tubing and dispersion tube should be purged with nitrogen or nitrous oxide at this time.

2. Add 20 cc deionised water to chamber 1.

3. Add 5 drops of Octanol defoamer to chamber 1.

4. Install the top of the gas train and hand tighten evenly to seal all O-rings.


5. Adjust the dispersion tube to approximately ¼” (5 mm) off bottom.

6. With the regulator backed off, connect the carrier gas supply to the glass dispersion tube of chamber 1 using flexible tubing.

7. Flow carrier gas through the train for one minute to purge air from the system. Check for leaks in the unit.

8. Fully collapse the gas bag and simultaneously check for leaks. To do this, connect the gas bag and stopcock to the hand pump (use a used Drager tube as connection and start with the bag essentially empty).. Fully depress and release the hand pump. When the bag is completely empty and free of leaks, the pump will remain depressed for several minutes.To check the pump alone, insert a sealed Drager tube into the pump opening and depress bellows. It will remain depressed if the pump does not leak.

9. With the bag fully collapsed, install flexible tubing from the stopcock and bag onto outlet of chamber 3.

10. Inject a measured volume filtrate into chamber 1 through the septum with a syringe and needle. See table below.

Carbonate range Sample Volume Drager Tube Tube Factormg/L mL Identification (see Calculation at end)25 - 75 10.0 CO2 0.01 %/a 25,00050 - 1500 5.0 CO2 0.01 %/a 25,000250 - 7500 1.0 CO2 0.01 %/a 25,000

11. Slowly inject 10 mL of sulphuric acid into Chamber 1. through the rubber septum, suing a clean syringe and needle. Gently shake the gas train to mix the acid with the sample.

12. Open stopcock on the gas bag. Restart the gas flow and allow the gas bag to fill steadily during a 10 minute interval. When the bag is firm to the touch (do not burst it!), shut off the flow and close the stopcock.

13. Break the tip of each end of the Drager tube.

14. Remove the tubing from Chamber 3. Outlet and install it onto the upstream end of the Drager tube. Attach the Drager hand pump to the downstream end of the Drager tube.

15. Open the stopcock on the bag. With steady hand pressure fully depress the hand pump. Release the pump so that the gas flows out of the bag and through the Drager tube. Operate the pump and count the number of strokes until the bag is empty.

16. Observe the purple stain on the Drager tube if carbon dioxide is present in the bag, and record the stain length in units marked on the Drager tube. (Include the faint blue tinge in the purple stain length reading)


4.4.7 PROCEDURE DFT/EAF/0013 - Methylene Blue Test for Mud and Shales

The cation exchange capacity (CEC) is a measure of the potential reactivity of the clay components of mud solids or shales. Clay minerals all exhibit ion exchange behaviour to some degree. Isomorphous substitution of various cations onto a clay surface depends on the number of available exchange sites per unit weight of solids, reported in lb/bbl or meq/100 g.

Cation exchange capacities in clay minerals is not a very precise or fundamental quantity, as it varies significantly with pH. Some reported CEC’s are as follows;

Vermiculites 120 - 200 meq/100gSmectites 80 - 150 meq/100gIllites 10 - 40 meq/100gKaolinite 1 -10 meq/100g

80 % of all sedimentary rocks are shales, which are generally composed of varying proportions of these clay minerals. The CEC of shales can generally be classed as follows;

Non-dispersive 0 - 10 meq/100gModerate dispersion 10 - 20 meq/100gDispersive 20 - 30 meq/100gHighly dispersive > 30 meq/100g

A EQUIPMENT

a) Methylene Blue Solution ( 3.74 USP grade)b) 3% Hydrogen Peroxidec) 5 N Sulphuric Acidd) 125 ml Conical Flaske) 25 ml Graduated Measuring Cylinderf) Hot plateg) Stirring Rodh) Filter paper, Whatman No 4i) 2 x 5ml Syringesj) 50 ml Burette and clamp stand

B PROCEDURE (Mud Solids)

1. Measure 2.0 mls of mud into the 125 ml conical flask.

2. Add a.) 15 ml of the 3 % hydrogen peroxide using a measuring cylinder. b.) 1 ml of the 5 N Sulphuric acid using a clean syringe.

Swirl mixture gently to ensure mud solids are completely dispersed within the mixture.

3. Place conical flask on a hotplate and heat gently until simmering. Leave to simmer for about 10 minutes.

4. Dilute to approximately 50 ml with distilled water and stir.

5. Add 1ml increments of the methylene blue indicator via a burette and swirl the flask vigorously for 30 seconds.

6. After each addition dip the end of the stirring rod into the solution and apply a drop to the filter paper.


7. The end point is reached when the colour of the blue solids containing droplet migrates away from the nucleus to form a light blue/turquoise halo.

8. Once you reach the end point it is important to keep stirring the mixture and dropping further solution onto the filter paper to ensure the end point is persistent and has actually been reached. Cation exchange is a time dependent process and the solution will go on reacting if all the sites have not been completely exchanged.

C CALCULATION

Bentonite (equivalent) ppb = mls of methylene blue solution X 2.5

D PROCEDURE (Shale)

1. Dry shale at 220 Deg F in an oven for 16 hours.

2. Grind shale using a pestle and mortar

3. Weigh 0.57 g of powdered shale into the conical flask and repeat steps 2 - 8 in the Mud Solids procedure above.

E CALCULATION

CEC (meq/100g) = mls of methylene blue solution x 1.95

Section 5Non-Routine Laboratory Testing Procedures

5 NON-ROUTINE TESTING PROCEDURES

5.1 INTRODUCTION

Non-routine testing procedures are defined as those which may not be applicable to an EAF district drilling fluids laboratory as the specialised analytical equipment required may not be available.

All these procedures are not recognised by the API testing procedures and in most cases have been developed by Dowell technical services to enhance the regional testing capabilities.

Both EATC and in most cases the UKI Aberdeen laboratory can perform any of the following tests on submission of a “Laboratory Analysis Request (LAR) “ form.

It should be noted that detailed procedures for certain analytical techniques are not given in this manual where a dedicated manual for a specific technique is available. More detailed procedures can be obtained through EATC by request, if required.

5.2 PROCEDURE DFT/EAF/014 - Particle Size Analysis (PSA)

The Malvern Mastersizer Micro Plus, an instrument based on the low angle laser light scattering (LALLS) is the EAF recommended particle size analyser. It was chosen not only for its small “footprint”, due to its novel folded optical configuration, but also because of several technical advances in the collecting and processing of data. An ultrasonic probe is also fitted to the unit for breaking up any aggregates that may be present in a sample prior to an analysis.

The instrument is capable of measuring particles in the range of 0.05 µm to 550 µm, which is adequate for most oil field applications.

A INSTRUMENT SPECIFICATIONS

Manufacturer : Malvern Instruments Ltd., Spring Lane South, Malvern, Worcester, WR14 1AT, UK; Tel./FAX - 01684 892456/892789

Instrument : Mastersizer Micro Plus

Model No. : MAF 5001

Particle Size Range : 0.05 - 550 µm

Technique : Laser Diffraction using Fraunhofer and/or Mie theories

Sample Type : Liquid suspensions only; (600 ml beaker; 80 ml small volume dispersion unit or 5 ml directly via syringe injection)

Operational Control : Computer controlled (P.C.) with manual overrides for flow rate and ultrasonication

Sample Dispersion : Mechanical flow loop and Ultrasonic Probe

Weight : 32 kilograms

Footprint : 500 mm * 325 mm


B PROCEDURE

1. Connect the Malvern Mastersizer to a PC by means of a 9-pin cable

2. Malvern software should be installed onto the PC according to the installation procedures on the disk

3. Ensure that both the Mastersizer and the PC are turned on

4. The Mastersizer software includes a row of dialogue boxes at the top of the screen. Setting up the software to run an analysis sample is simply a matter of working through the first four of these dialogue boxes in turn and providing the information requested.

5. Click on the first dialogue box - Set-up Range, Analysis and Presentation

6. Accept default settings (Internal-Micro Sample Dispersion Unit) (Instrument Port 1)

7. Set up Analysis - Enter particle density if known (SG of sample) and the refractive Index (RI) of the base fluid, if known. For example the RI of Ultidrill is 1.4381. Accept other default settings

8. Set up presentation - Load default settings

9. Click on second dialogue box - Open a Sample File and Load a Record

10. Enter the desired file name and click on OK

11. Click on third dialogue box - Document Sample Details

12. Enter desired sample name

13. Enter any notes e.g. sample source, date, time and any other relevant details

14. Click on OK

15. It is necessary to set the Mastersizer and start its operation before moving on to the fourth dialogue box as this will start the sampling process.

16. Put approximately 500ml of clean base fluid into a beaker and place under the instrument motor.

17. Lower the motor down into the fluid taking care that the suction holes are fully immersed but that the motor does not touch either the bottom or sides of the beaker

18. On the instrument control panel, press the on button and allow the motor to come up to speed. The recommended motor speed is 2000rpm. Speeds in excess of this create excessive noise and can result in cavitation and bubble formation whereas significantly lower speeds may result in not all of the heavier solids being carried through the sampling system.

19. The machine is now set up and ready to sample. To start the operation click on the fourth dialogue box.

20. Follow the on screen instructions

21. To start the operation, press the space bar. This will start the Laser Alignment. We are looking for a laser power in the region of 70 for the first laser and in the region of 6 for the second laser.


22. Press the space bar to continue the background measurement. Caption should read “Measure - Background”

23. Press the space bar again to start the measurement

24. Obscuration readings should remain very close to 0.0%. A higher obscuration indicates an impure base fluid or the presence of dirt or contamination within the instrument. Background measurement is complete when the button changes from STOP to START and the message “Press Space Bar to Continue” appears

25. Press the space bar to move to the Inspect phase

26. The Measure Window changes to “Measure - Inspect”

27. Collect around 0.5 to 1ml of sample mud in a syringeAdd sample a little at a time to avoid saturation - a very small quantity of mud is required. The actual amount will depend on the solids content of the sample

28. As material is added the obscuration will increase and the central display column will exhibit a “traffic light” display changing from red to amber and finally to green. There is not sufficient sample to analyse until you are in the green section. This should have an obscuration reading in the range 12 - 18%; ideally 15%

29. When the desired value is reached, press the space bar to go onto the Measure Sample stage.

30. Press the space bar again to start the measurement

31. When the message “Press Space Bar to Continue” appears, press it to start the calculation.

32. When calculation is complete the window will automatically disappear and the results table and graph will be displayed. (Clicking on the box “Pause after each stage” will automate the set-up procedure. i.e. the switch between laser alignment, obscuration, background and sample analysis will proceed automatically without the need to press the space bar between each measurement).

33. Analysis is now complete but results must be saved and reported

To save the results

34. Click the Save Record button. This automatically saves the results in the next record of the open file.

35. All data must be down loaded to floppy disks and backup copies made.


To print a report of the results :

36. Click the Print button37. Click the “report “option to choose this format38. Print report39. The report will be printed out in a similar format to that shown on the screen:40. Sample details will be displayed at the top of the report. These include the file name

and sample name that was input in the earlier stages along with any notes that were added. The time and date of the analysis are also displayed.

41. The next section reports system details such as the sampler used (internal or small volume), any modifications made and the beam obscuration.

42. The third section is arguably the most important as it details all the results statistics. These include the percentage of particles found in each size range

43. The final section is the graphical plot of the results and is the easiest method of obtaining a quick comparison of results. The main axis show particle size against the percentage of solids. The easiest method of obtaining a comparison of test results with the desired results is to have a graphical display of the desired solids profile. This should be obtained by laboratory testing prior to taking the Mastersizer offshore.

44. This desired profile should be loaded on to the computer by clicking on the file command and selecting “Open Sample File” from the menu. Select the required file (containing the desired solids profile) from the list and it will be opened onto the screen. Repeat this operation to open the file containing the results you want to compare. This plot will automatically be superimposed on the desired profile that was opened earlier. (If you want to open files without superimposing them onto earlier ones the plots already displayed should be erased by clicking the box at the top of the display that shows a graph with a cross through it).

45. When carrying out a PSA on a PPA (- Pore plugging Apparatus ) filtrate the most important trend to look for is an increase in fines content of the sample. If this is seen it indicates that the filter cake is poor or even breaking down and that fine particles will be migrating into the formation, thus running the risk of blocking off pores if we are in the reservoir section.

C. CLEANING AND MAINTENANCE OF PSA

1. Basic cleaning before and after every analysis is essential in order for the machine to operate. Failure to clean the apparatus will result in “Data Saturation” messages.

2. Before and after each measurement the system should be flushed through with fresh base fluid. This is simply done by lowering the motor into a beaker of clean fluid and allowing to circulate for a few minutes at a minimum of 2000rpm. The cell window should also be cleaned. This is also a simple operation but care must be taken to avoid damage to the window. Cleaning procedure is as follows:

3. Lift motor out of fluid and turn off

4. Open draw fully and turn handle anticlockwise to release window

5. Lift off upper window taking care not to touch the window itself

6. Dry the area around both upper and lower windows with paper towel, but do not touch window with the paper towel

7. Using a lens tissue clean each window in turn using one simple stroke along the length of the window. Do not wipe the window round in several directions.


8. If the windows have dried, breath on them to produce moisture before gently cleaning with a lens tissue in the same way as before. Never clean a dry window - this produces scratches

9. Under no circumstances should materials other than lens tissue be used to clean the cell windows - this will result in permanent damage necessitating window replacement at a cost of $150 per window!

10. Particularly stubborn solids can be removed by gently washing with Acetone from a wash bottle. The cleaning tissue can also be moistened with methanol and white spirit to aid removal of solids.

11. If the instrument gets particularly dirty, or any case a minimum of every 4 days, the system should be cleaned by flushing with warm soapy water for several minutes. This same procedure must be used every time the system is changed from oil to water based mud and every time use of the machine is ceased.

12. The aperture between the upper and lower cell windows is only 2mm. It is therefore essential that no solids of a larger size than this are introduced to the system. If they are they can not only damage the lenses but may also become trapped between the windows or in the tubing. In order to ovoid introduction of this size of particle it is recommended that any samples taken from before the shale shakers are run through the mesh of a Marsh Funnel to remove course solids first. The use of a vortex machine may also be necessary to further reduce solids size in the system.

13. Should the windows become damaged they can easily be changed out, however they are expensive so all precautions must be taken to avoid damage in the first place, To change out a window follow the procedure below:

14. Open the draw on the Mastersizer housing the cell windows

15. Remove the retaining rings by inserting the pegs on the round removal tool into the holes on the ring. Rotate anticlockwise to remove the ring.

16. The windows are held in place by “O” rings and can easily by pushed out by applying gentle pressure to the upper surface of the window. Use a lens tissue between your thumb and the window to avoid direct contact and place paper towel on the bench below to catch the window as it comes out.

17. To replace the window, first fit the “O” ring to the retaining ring then gently push the window into position using the same technique as for removal. The window has a tapered edge and the widest side must face outward. It must be fully home in the mount not simply held by the “O” ring otherwise it will move as pump speed changes and lead to miss-alignment of the lasers. Use the window tool to reinsert the window. Check for any leaks by inserting the window, lowering the pump into base fluid and increasing pump speed to 3000rpm. With the window draw open, hold in the yellow override button to begin circulation and check that there is no seepage from around the window.

D. TROUBLE SHOOTING

1. The message “Data Saturation” appears - This is normally caused during the background measurement phase by poor cleaning practices. It can be overcome by cleaning the cell windows again and flushing through with base fluid for several minutes.


1. If the message occurs during the analysis phase it is usually due to adding too much sample. Unfortunately it is usually too late to do anything about this now although it may be possible to continue with the measurement and still get reasonable results, depending on how saturated the solution has become. In any case, thorough cleaning of the system will be required on completion.

2. The pump will not start - The pump is not in the solution or the cell window top is not in place. Alternatively the cell draw could be open

3. The pump display flashes - The pump is turned on but is in the raised position or the cell draw is open. If this is not the case it could be that the cell top is not properly fitted. If the fluid is particularly viscous it is possible that the pump cannot reach the requested speed and this will cause the display to flash. If all the above have been checked and the display still continues to flash when the pump is place in water, there is a fault in the system and Malvern should be contacted to rectify it.

6. The message “Instrument is not responding. Do you wish to retry?” appears when the Mastersizer starts - Check that the communications cable between the Mastersizer and the PC is properly connected to both the instrument and the PC then click “Retry”.


5.3 PROCEDURE DFT/EAF/015 - HTHP Rheology - Fann 70

The Fann 70 has the capability to measure the rheology of fluids up to 500 deg F and 20,000 psi.

Fluids containing magnetic particles, such as haematite or micromax CANNOT be put in the Fann 70 due to the damage that can be done to the torsion magnets. The fluid will not remain homogeneous due to the magnet at the bottom of the rotor pulling the particles out of the fluid to congregate at the base of the rotor.

A PROCEDURE

1. Turn on the Fann 70 at the main power switch on the console. The pressure gauge should light, and the speed display should flash briefly if the speed switch is in the "STOP" position.

2. Press the "HEAT/COOL START" switch until the temperature controller comes on. Two alarms on the controller, which can be seen at the top left hand corner of the controller will illuminate and switch off by holding the switch in. When the alarms are no longer illuminated the controller can be used. If the "MAN" light on the controller is not flashing press the "START / STOP" key to prevent the controller from heating up or cooling down.

Building The Test Cell3. Start with all parts of the cell clean. If they are not, clean the cell before using it. The

cell itself, the rotor assembly, bob, and bob shaft must be free of anything that may contaminate the sample, or cause damage to the threads of the cell. If there is any pressurising fluid left over from a previous test remove it from parts of the cell where it may come into contact with the Coupling threads.

4. Ensure that the top of the cell assembly is on it's stand with the locking pin in place, preventing the cell from dropping off the stand.

5. Screw the cell baffle snugly into place in the bottom of the Coupling, or middle part of the test cell. Pass a metal rod through the holes in the baffle to tighten it sufficiently. If the cell baffle is not sufficiently tight then it may unscrew during the test until it touches the top of the bob. It may press down hard enough to damage the bob's Vee jewel. If the torsion dial reading stops changing during a test there is a good chance that this is what may have happened.

6. Screw the bob onto the bob shaft, until the bob is fitted tightly onto it.

7. Screw the bob shaft assembly plus the bob through the whole in the cell baffle into the limit stop at the top of the test cell.

8. Check the condition of the rotor. If necessary replace the pivot bushing, rotor bearing race and the rotor ball bearing as described in section 6.3 in the Fann 70 manual.

9. Remove the cell seal o-ring and backup ring if they are installed.

10. Place the rotor assembly into the cell. Take care not to bang it against the pivot point. Do not drop the cell into place as that may damage the pivot ball bearing. Lower it gently into place and check that it rotates freely .

Filling The Cell


11. Place 140 mL of the sample into the test cell until it reaches the top of the rotor. Ensure that there are no air bubbles in the sample by rotating the rotor in the sample.

12. Place the o-ring and backup ring into the cell. The viton 0-ring is placed in the groove first, followed by the metal backup ring with the bevelled side down.

13. Lubricate the lower threads of the Coupling with a small amount of Anti-Seize grease to prevent thread galling, which can ruin the cell assembly.

14. Place the cell under the Coupling on the stand. Lift it up and screw it onto the Coupling until the threads are hand-tight. The cell can be screwed on tighter with the use of a strap wrench.

15. If during this process resistance is felt before the cell is fully screwed onto the Coupling stop and investigate the cause. The torsion assembly may be jammed. Unscrew the cell and check that the torsion assembly is not jammed by rotating the top magnet with a non-magnetic wire or rod. Check that the o-ring and backup ring, baffle and bob are in the correct place.

16. Fill a 20 ml syringe with 16 mls of sample and place a 1 mL syringe with no plunger on the end of it. Place this double syringe into the sample port. (This can be located by looking for the engraved "Baroid Model 70" on the top of the cell. The sample port is to the immediate right of this engraving when looking straight at it.)

17. Inject 15 mL of the sample into the sample port until the sample has risen up to just below the sample port in the bob shaft. Any more than 15 mL of the sample will cause contamination of the pressurisation fluid in the torsion assembly. Place Anti-Seize lubricant on the threads of the sample port. Screw the sample port cover into the sample port.

18. Check that the viton o-ring and backup ring are in place at the top of the cell. The backup ring sits on top of the o-ring with the bevelled side facing down.

19. Screw on the cap until it is hand tight.

Installing The Cell In The Hot Well

20. Remove the locking pin. Lift the cell carefully from it's stand into the Hot Well with the plugged sample port facing out of the hot well.

CAUTION

The test cell weighs 29.6 pounds (13.4 kg) when empty and should be carried with two hands and extreme care.

21. Apply Anti-Seize lubricant to the threads of the other two ports.

22. Screw in the port connectors until they are hand tight. It may be necessary to rotate the test cell slightly to line up the ports with the connectors.

23. Tighten the single connector locking screw at the right hand side of the heating jacket.

24. Check the level of the pressurising fluid in the pump reservoir. If necessary fill with more Marcol 172 oil.

25. Check that the Reservoir return valve on the pump (round black valve) is closed. Open the pressure release valve on the side of the reservoir tubing. Stroke the pump at least 20 times with the pump handle, and continue until you hear a last of air being forced from the plastic drain tube underneath. Continue pumping until you


obtain a continuous flow of oil from the drain tube and then close the pressure relief valve.

Pressurising The Cell

26. Close the vent valve and pressurise the cell to the desired pressure. 1000 psi is usually sufficient to see if there is a pressure leak from the test cell in the heating jacket. If no fluid leaks out then the cell is holding pressure. If fluid leaks out of the cell, then pressure must be slowly released and the cell must be removed from the well. Usually all that is required is to tighten the seals between the joins of the cell, or to check that the o-ring and backup ring are in the correct position. If the o-ring has perished under the pressure it must be replaced.

27. If the cell is not leaking then the door of the hot well can be closed slowly. Push the door pin all the way down to lock the shield closed and to properly position the dial sensor in the top of the door. If the readings are obviously false due to closing the door too quickly, the solution is to open and close the door slowly.

28. A slight pressure leak at the beginning of the test, viewed on the gauge is quite normal and should stabilise within a few minutes.

29. Using the speed selector button set the fluid spinning at 200 RPM.

Programming The Controller

30. To set an end point for the temperature press "TUNE", "LAST" then "YES/ UP ARROW" keys. Use "PARAM CHECK" to scroll through the program parameters.

31. When "RAMP AND SOAK ?" appears on the display press the YES/ UP ARROW" key. "SET PT 0" will appear on the display. This should be equivalent to room temperature, i.e. about 25˚C.

32. Press "PARAM CHECK". "TIME 1" will appear on the display. This is equal to the time that the sample of fluid will take to reach the test temperature. This can usually be programmed to be about an hour or slightly less than that if required. The "UP" and "DOWN" arrow keys can be used to alter the time that is taken to reach the test temperature. The time will be displayed as hours : minutes. This is known as the first ramp.

33. Press "PARAM CHECK". "SET PT 1" will appear on the display. This is equal to the test temperature in degrees centigrade.

34. Press "PARAM CHECK". "TIME 2" will appear on the display. This is equal to the time that the sample of fluid will stay at the test temperature. This is usually left at 99 hours and 59 minutes. This is known as the second ramp.

35. Press "PARAM CHECK". "SET PT 2" will appear on the display. This is equal to the test temperature in degrees centigrade.

36. Press "PARAM CHECK". "TIME 3" will appear on the display. This is equal to the time that the sample of fluid will take to ramp to the third temperature, if there is one. This is usually left at 0 hours and 00 minutes.

37. Press "PARAM CHECK". "CYCLES" will appear on the display. This is the number of times that the program will run through the temperature ramps before it stops heating.

38. Press "PARAM CHECK". "ASSURED SOAK" will appear in the display. Press the "NO / DOWN ARROW" key.


39. "END OF TUNE" will appear on the display. Press the "TUNE" key. This will take the display back to the temperature of the fluid in the heating jacket. If there is a difference between the temperature of the sample and the set point 0 temperature change it until they match.

Running The Test

40. Press the "START / STOP" key to commence heating the sample.

41. The fluid can be left to heat to the test temperature. Due to the length of time that is taken to relay the signal to the heater the temperature in the test cell can take up to several hours to stabilise. (This is a well known design fault which will not be rectified in the near future.) One hour is usually sufficient for this to happen.

42. Once the fluid is at the correct temperature adjust the pressure on the cell to what has been requested by the client.

CAUTIONThe Fann 70's pressure lines are only rated to 20,000 psi and the pressure placed on the cell must NOT be greater than this.

43. Take the desired rheology readings. If required take gel strength's. The 10 second gel is relatively meaningless, as the it takes more than 10 seconds for the motor to activate from stationary!

Ending The Test

44. Once the test is complete, press the "START / STOP" key on the temperature controller to stop the heating process.

45. Press the "MAN" key.

47. Press the "DISPLAY" key until "OUT 2" appears. Using the "YES / UP ARROW" turn this to 100 %. This will start the cooling water.

48. If the "OUT 2" does not change, press the "START / STOP" key again.

49. Once the cell has cooled to room temperature, decrease the "OUT 2" to 0 %. This will disable the cooling and heating action.

50. When the test cell has cooled to room temperature, release the pressure on the cell slowly using the pressure release valve. When there is no more pressure on the test cell it can be dismantled safely.

51. Unscrew the Coupling lock pin, and disconnect the pressure lines at the port Couplings.

52. The cell can now be lifted out of the hot well. A vacuum pressure will have built up behind the cell and this must be broken by turning the cell around in the heating jacket. Extreme care must be taken when lifting the cell out of the hot well due to the weight of the cell.

53. Place the cell on it's stand and secure it in place with the locking pin.

54. Dismantle the cell and clean all parts thoroughly with detergent. Ensure that the magnet at the bottom of the rotor is clean and that it does not become too worn. Any sediment from the fluid that may have accumulated around the pivot or in the rotor must be removed.


55. The shaft and bob must also be cleaned and the top and middle parts of the cell must be cleaned so that no fluid blocks the sample port. The pressure ports must also be kept clean so that pressure will not build uncontrollably during a test.

Resetting The Mechanical Zero

56. Once the cell is clean and dry, make the cell up with no fluid in it.

57. Place the cell into the hot well and connect the port connectors. Close the shield door. If the reading on the display is at, or close to 0 then remove the cell. If it is not then the mechanical zero must be reset.

58. Remove the cap of the cell and loosen the Allen screw in the pivot cap. Remove the pivot cap. Adjust the position of the torsion magnet by loosening the screw and rotating the magnet clockwise or anticlockwise in small amounts. The magnet should be tightened and the shield door closed. If the reading on the console is within the limits of ± 5 of zero degrees then this is an allowable amount. As close to zero as possible within 2 degrees is better.

59. Continue moving the magnet until the closest reading to zero can be achieved.

60. Replace the pivot cap. Replace the cell cap. Disconnect the port connectors and remove the cell from the hot well.

61. Dismantle the cell and leave for the next test.


5.4 PROCEDURE DFT/EAF/016 - Pore Plugging Apparatus (PPA)

The primary function of the PPA is to characterise the bridging efficiency of a fluid by measuring its spurt and mud loss through a ceramic disk of fixed permeability over time. This then helps in designing a fluid with the optimum bridging agents present which are best suited to match a formations permeability.

A. EQUIPMENT

a.) A specially adapted double ended HTHP filter press cell is used for this test. Before starting it is necessary to check all the “O” rings are in good condition and that the tips of the valve stems are not corroded or blocked. The heating jacket should be set at the desired temperature.

b.) Aloxide (fused aluminium oxide) disc of desired permeability

B. PROCEDURE

1. The ALOXIDE disc of the required permeability should be soaked in base fluid until bubbles cease to be given off (usually around 5 seconds). This ensures that it is wet and best emulates formation conditions.

2. The cell should be inverted and the required size of ALOXIDE disc inserted.

3. The stem should be tightened into the lower cap and the cap inserted. Screws should be tightened gently working on opposite screws in sequence and continuing round the cell until the cap is in place and the screws are flush. Care must be taken not to over tighten any screw as this can result in cracking of the disk.

4. The cell should now be filled with mud to within 1/2” of the upper “O” ring. The upper valve stem is inserted loosely and the lid fitted in the same manner as the lower cap was. The valve stems must now be checked for tightness and the cell inserted in the heating jacket (ensuring that the ALOXIDE disc is on the bottom).

5. The thermometer/temperature probe should be inserted into the cell and the upper and lower pressure units fitted.

6. Adjust the upper pressure unit to 200 - 300 psi and open the upper valve stem.

7. When the required temperature is reached the upper pressure unit should be adjusted to 100 psi above the required pressure and the lower unit adjusted to 100 psi. Open the lower stem and start timing. The pressure limitations of the cell should be taken into account. Generally, differential pressures greater than 500 psi should be avoided.

8. During the test watch for a pressure build up in the lower unit. If this occurs, bleed off some of the filtrate into a measuring cylinder.

9. After 30 minutes, close the lower valve stem and then the upper valve stem to isolate the pressure inside the cell.

10. Bleed off the filtrate into a measuring cylinder. Record the PPA fluid loss as twice the volume of filtrate collected.

11. Dismantling should be carried out with care. It is important to ensure that all pressure has been bled off prior to loosening the grub screws. This is done by inverting the cell and carefully loosening the valve stem. Ensure that the stem is pointing away from people as the pressure is bled off. Loosen the grub screws and carefully remove the cell lid.


NOTE:Fann has now introduced a new HTHP cell that does not use the set screw secured end caps. The caps spin up or off without tools and are much easier to use than the old style that has been used for years. The new version should be acceptable to Schlumberger HSE for pressures above 1000 psi (which the old style apparently is not).

5.5 PROCEDURE DFT/EAF/019 - Back-Flow Tester Procedure for “Wire

Wrap” Screens

The Back-Flow tester is a qualitative means of evaluating in the laboratory the likelihood of a

wire wrap screen plugging in the field when a specific fluid is flowed through it. Generally,

Johnson screen disks, including pre-packs, of variable screen gauges would be used.

A. EQUIPMENT

a.) 500 ml Double Ended cell (acrylic or stainless steel), milled at bottom end to accommodate wire wrap screens.

b.) Top End cap, 2000 psi (OFI p/n 170-24, fitted with 0-30 psi low pressure gauge and soda siphon assembly.

c.) Bottom End cap, 2000 psi (OFI p/n 170-24), milled thin and fitted with a Parker gate valve and compression fittings.

d.) Excluder wire wrap screens

e.) Large size O-rings, Buna N, OFI p/n 170-13

f.) Allen key for grub screws and an adjustable spanner for connections

g.) Adjustable stand

B. PROCEDURE

A fixed volume of 350 ml of fluid is flushed through the assembled back-flow cell at 5 psi

pressure and at ambient temperature, and the time taken for complete evacuation of the cell

noted. Initially, de-ionised water should be used in order to establish a base line value.

Ideally, three 350 ml aliquots of test fluid should be used, and at the end of the test de-

ionised water flushed through once again in order to ascertain whether or not any serious

plugging had occurred with the test screen.

1. Set up the back-flow test cell containing the clean wire wrap screen section by carefully fitting the test screen into its retaining ring. An O-ring seal should be fitted, and stainless steel spacers used when testing with single screens.

2. Place bottom end cap into position, with valve closed, and tighten retaining grub screws.


3. Fill the cell with 350 mls of either distilled water or screened test fluid, and replace and tighten top end cap.

4. Place graduated beaker/jug under cell and apply 5 psi to cell.

5. Open bottom valve and record time to evacuate the cell.

6. If all the fluid passes through the cell, then repeat steps 3 to 6 with two further 350 ml batches of fresh fluid and the same screen.

7. If all 3 batches of mud pass through the screen without plugging then the test is considered successful, noting that flow times must be similar.

8. If the screen plugs, i.e. incomplete flow of any of the three batches at 5 psi; (a) the volume of fluid collected should be recorded, and (b) a pressure of 25 psi should be applied to the cell and the evacuation time recorded as before.

9. Release applied pressure if cell becomes plugged BEFORE unscrewing the top regulator.

10. Inspect the screen visually for evidence of plugging and report any findings.

C. INTERPRETATION

∑ A successful result is the flow of all 3 batches of fluid through the wire wrap screen at a

maximum pressure of 5 psi.

∑ Complete flow through the wire wrap screen at 25 psi is NOT satisfactory. However,

testing at that pressure will quantify the severity of plugging.

∑ Incomplete flow indicates that further mud conditioning is required over the shaker

screens to preclude screen plugging.


5.6 PROCEDURE DFT/EAF/020 - Mud Solids Monitor (MSM)

The MSM Mud Solids Monitor is a field proven and accurate analytical technique for measuring drilling fluid composition. It measures barite, low gravity solids (LGS), potassium and chloride concentrations and is an extremely valuable tool for fluids monitoring and for analysis of solids control equipment performance. Barite/LGS and salt measurements work in all major drilling fluid types except salt saturated water based systems.

The whole analysis process from analysing the sample to obtaining the results takes about 5 minutes.

For fluids monitoring, the MSM package allows the low gravity solids (LGS) and high gravity solids (HGS) content to be measured much more accurately and faster than with a traditional retort. The MSM package measures the barite and other ions such as chloride, potassium and calcium directly and also measures the total liquid phase. The LGS is then calculated by closing the mass balance, giving a typical error of +/- 1% v/v. With the retort, LGS cannot be measured with any degree of reliability and the use of this property to control dilution rates can lead to expensive mistakes, either through excessive dilution leading to higher mud costs or more usually by insufficient dilution leading to poor drilling performance and greater chance of major drilling problems and higher overall drilling costs. The MSM package also offers the valuable additional benefit of accurate potassium measurements. This allows the engineer to monitor potassium depletion rates and ensure that appropriate inhibition levels are maintained.

The MSM package can also be used as a quality control tool to analyse barite either in the laboratory or at the rigsite. Barite quality is important for drilling fluid performance, particularly in the heavily weighted muds that are normally used in critical HTHP wells.

A DETAILED OPERATING MANUAL IS AVAILABLE FOR THE MSM, WHICH CAN BE OBTAINED BY CONTACTING EATC SUPPORT STAFF IF REQUIRED.


5.7 PROCEDURE DFT/EAF/021 - Fluids Ion Monitor (FIM)

The Fluids Ion Monitor is a low cost fully upgradeable systems to provide ion analysis capabilities for a variety of applications.

Schlumberger Dowell utilise the FIM quantitatively to measure cations and anions in the aqueous phase of water based drilling fluids. Common analyte ions detected by the FIM are:

Sodium, Potassium, Magnesium, Calcium, Barium, Strontium, Formate, Chloride, Nitrate, Bromide, Sulphate and Phosphate.

The system is based on the principle of ion exchange chromatography, analyte ions are injected on to ion exchange column whereby they are separated according to their hydrated ionic radius and their charge. Once the ions are separated they pass through a conductivity detector. The conductance reading is proportional to the concentration of each ion. The system is calibrated by using a external calibration standard solution containing the analyte ions to be measured.

Components in the system are as follows; pump unit, ion exchange column, chemical suppressor column, conductivity detector, data aquisition.

The FIM is capable of measuring all the major ions in a drilling fluid filtrate to within +/- 1% accuracy in a time frame of 15 minutes.

A DETAILED OPERATING MANUAL IS AVAILABLE FOR THE MSM, WHICH CAN BE OBTAINED BY CONTACTING EATC SUPPORT STAFF IF REQUIRED.

106218846 Schlumberger Dowell Lab Manual

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Transcript of 106218846 Schlumberger Dowell Lab Manual