Industry standards – a blessingor a curse?
Transcript of Industry standards – a blessingor a curse?
Industry standards –
a blessing or a curse?
Alexandra Torgersen
NRC Malmø 9-10 april 2014
2013-ATE-PN-105
Floating Production Storage & Offloading Vessels
Turret Mooring Systems
Tension Leg Platforms
Light Well Intervention
Guidelineless Deepwater Trees
Subsea ManifoldSmart Well
Control Systems Subsea TemplateSystems
Standard Subsea Trees
Metering & Control Systems
Surface Well Systems
ROV Tie-In Systems
Subsea Processing
Subsea Drilling Systems
Oilfield equipment
Production environments
• Subsea production: Seals, gaskets, packoffs, connectors, diaphragms.
• Temperatures from - 50 oC to 180 oC possible. Pressures up to 1,000 bar differential.
• Resistance to production/injection fluids, gases, chemicals, acids.
• Mechanical abuse is less than drilling.
• Subsea applications are very critical due to cost (millions of $) and environmental issues.
• Service life of 20 to 30 years or more.
What is the basis for industry
standards?
• Common minimum requirements for specific
equipment
• Collective industry knowhow and
understanding
• Eliminate common mistakes/challenges
• Guide to ensure fit form and function
Why do we need them?
• Alternative is every company making their
own rules
• Assist and guide newcomers to understand
challenges in industry
• Assist and guide everyone to deliver
equipment that works
10
Offshore development
©Statoil
Wells/Downhole equipmentMaterial SelectionFabricationFatigueHigh temperature
FlowlinesMaterial SelectionPlastic deformationHigh temperatureCorrosion inhibitorsCP Coating
RisersMaterial SelectionFabricationFatigue
Export pipelinesFabricationRunning fracture
HullFabricationCP/ coating
TopsidesMaterial SelectionCoating
Subsea XT and TMMaterial SelectionFabricationFatigueHigh temperatureCP/ Coating HISC
Drilling/ WorkoverMaterial SelectionFabricationFatigue
ISO 13628/API 17ISO 10423/API 6A
DNV OS-F101 DNV OS-F101
DNV OS-F201
NORSOK
NORSOK/ISO/API
DNV DNV Class Rules
Typical subsea industry elastomer testing
philosophy
• Production system: all seals typically qualified per NORSOK M710,
ISO23936, and ISO10423 (API 6A)
• Hydraulic system: many seals accepted as field proven. ISO 13628-6
covers materials testing.
• Chemical injection system: primarily metal seals or thermoplastic seals
(PEEK, PTFE) which have very high chemical resistance. Elastomers
typically tested (immersion testing). No specific industry standards, but
can be covered using NORSOK M710, ISO 23936. Often ISO 1817 is used.
• Completion fluids: exposed seals tested (immersion testing) in completion
brines. No specific industry standards, but can be covered using NORSOK
M710, ISO 23936. Often ISO 1817 is used.
Industry standards
• Subsea production seals:– NORSOK M710
– ISO 23936
– ISO 10423 / API 6A
• Subsea hydraulic fluid seals:– ISO 13628 part 6
• Downhole seals:– ISO 13533
– ISO 16070
– ISO 14310
• General:– ISO 1817
NORSOK M710 –production fluid seals
• Scope: production seals
– Seals wetted by production fluid
• Provides methodology for qualification of
materials and manufacturers
• QC requirements
• Material standard only, no functional
requirements or testing
NORSOK M710 – Service life prediction
• Methodology:
– 3 test temperatures
– Durations long enough to achieve >50% drop in
tensile properties
– Standard test fluids; sweet and sour service.
Bespoke fluid is an option.
– Arrhenius extrapolation of test results to provide
service life at different temperatures
NORSOK M710 – Service life prediction
• Benefits:– Very good comparison tool for evaluating different material choices
– Provides indications of service life at temperature based onextrapolation
– Long test times provide understanding of degradation behavior in material
• Challenges:– Method not suitable if deterioration is not linear
– Unsuitable if no deterioration occurs, or if reaction is abrupt
– Comparison tool only, not suited to give absolute application driven parameters
– Pure material test, not application specific
– Uncertainty in accuracy of extrapolation
• Methodology:
– Test jig with O-rings exposed to a standard gas
mixture
– Temperature either 100°, 150° or 200°C – most
testing done at 100°C
– Pressure set at 150 bar
– 10 decompressions
– Evaluation of O-rings after decompressions
NORSOK M710 – Rapid Gas Decompression
• Benefits:– Easy comparison between materials
– Good method for understanding level of resistance to RGD in individual materials
• Challenges:– Testing done on unsupported O-rings
– Supported seals with good design may functiondespite failure in RGD test
– Not directly translatable to real applications
– Testing done at lower temperatures and pressuresthan normally seen in applications
NORSOK M710 – Rapid Gas Decompression
ISO 23936 – production fluid seals
• Part 1 thermoplastics – will not be covered as this is not
typically used in the industry. Not a good standard.
• Part 2 elastomers – based on NORSOK M710. This standard
will most likely replace NORSOK M710 for elastomer
requirements.
ISO 23936 – 2
• Same scope and methodology as in NORSOK M710 – elastomers only
• Also covers hoses, flex joints, downhole packers, bridgeplugs and BOP seals– Materials testing is same as for production seals
• Provides methodology for qualification of materials and manufacturers
• QC requirements
• Material standard only, no functional requirements or testing
ISO 10423 / API 6A – WH, XMT, WO
• Scope: functional requirements for wellhead
(WH), Xmas tree (XMT) and workover (WO)
equipment
• Annex F provides functional test requirements
for non-metallic seals
• QC requirements
ISO 10423 Annex F1.11 (PR2 test)
• Methodology:– Cyclic temperature and
pressure testing of sealingsystem using actual seal and gland
– Temperatures: TMin, TRoom, TMax
– Pressures: PNom, PMax
– Test medium: water / water based fluid or Nitrogen gas
– Hold points: 1 hr
– Acceptance criteria: pressuredrop
ISO 10423 Annex F1.11• Benefits:
– Functional test of actual sealing system
– Gas medium provides applicable testing for gas sealing systems
– Sealing at both low and high temperatures is a challenge, and thus design is verified to full range of application
• Challenges:– Acceptance criteria of pressure drop too
lenient for gas applications: should use «zero bubbles»
– Pressure releases may occur too rapidly and cause inadvertent RGD effects – needs to be controlled
ISO 10423 Annex F1.13
• Methodology:
– Immersion test using actual seal and groove
– Test fluid is sweet or sour service
– Temperature and pressure is max for application
– Duration is 160 hrs
– Post exposure pressure testing at high and low
temperature with sealing as acceptance criteria
ISO 10423 Annex F1.13• Benefits:
– Methodology combines functional testing and exposure testing
– Acceptance criteria of no leakage proves functionality after exposureto production fluid
• Challenges:– Exposure duration too short for any real measure of long term effects
– Does not cover RGD effects
ISO 13533 – BOPs
• Scope: functional testing of
BOPs, both RAM type and
annular type
• Material requirements not
covered, should use ISO
23936
• Testing covers both sealing
function, shear function
and temperature/pressure
cycling
ISO 14310 – Packers and bridge plugs
• Scope: Functional standard covering packers
and bridge plugs for down-hole applications
• Several levels of validation testing – V5 to V0,
where V0 is the most stringent level.
• V0 requires gas sealing tests at temperature
and pressure with zero bubbles as
acceptance criteria.
• Requirement for manufacturers are included
in standard
ISO 13628-6 – hydraulic fluids• Scope: functional and
material testing ofhydraulic fluid – mayalso be used for polymer/elastomer materials
• Annex C covers qualification of hydraulicfluid
• Standard not specificallywritten for qualificationand testing of materials
Different NBR’s exposed to control fluid
ISO 13628-6
• Methodology:
– Immersion type testing of materials in
hydraulic fluid
– Temperature: 70°C and TMax
– No pressure required
– Duration up to 3 months with
intermediate durations at 1 week and
1 month
– Post exposure testing do not include
tensile testing
ISO 13628-6
• Benefits:
– Generic test for all types of materials in hydraulic fluids
– Easy to compare different materials
– Long test duration
• Challenges:
– Lack of mechanical testing of materials required
– Only two temperatures makes it impossible to perform
Arrhenius extrapolations
– No functional testing of sealing systems required
Soft Seal Qualification Guideline
• Guideline describes scope for
relevant subsea soft seal
industry standards – what it
DOES test for and what it
DOESN’T test for ….
• Gives both benefits and
challenges with each standard
• Provides tips on how to best
use each standard
Qualification summary• Standards offer a set of rules and regulations for soft seal
qualification – however it is always «fit for service» that
is ultimate goal
• Many applications not well covered by standards
• Many service environments outside standard
temperatures, pressures and chemistry covered by
standards
• Use standards as guide to qualification testing, NOT as
the Bible – the application must always come before
industry requirements