Inspection and Test Plan for Reciprocating Compressor

This article, detailing the inspection and test plan for reciprocating compressor, provides you with information about reciprocating compressorinspection and testing in a manufacturing shop. The draft Inspection and test plan for water tube boilers is provided as well.

The API 618 standard requirements are normally applied for the inspection and test plan in a manufacturing shop.

TThe witness of some inspection and testing by third party inspectors is mandatory and cannot be waived.

Some others must only be monitored and full witnessing is not necessary; for these items, the inspection man-days etc. depend on the purchaser’s decision. Some prefer stringent monitoring and even assign a resident inspector in the manufacturing shop, and others relay to the quality control system of the manufacturer and assign only a few days for monitoring points.

These are some of the inspection points that need to be witnessed, checked monitored and reviewed by a third party inspector for a reciprocating compressor construction.

Inspection and Test Plan for Reciprocating Compressor - Important Points

Reciprocating Compressor casings to be identified against foundry test certificates and thicknesses checked to conform to approved drawings.

Witnessing hydro-static test on reciprocating compressor cylinder, cooling jackets, piping, pressure vessels, filters and coolers.

Checking assembly of piston end clearance, crankshaft deflection, run-out check, proper match marking and protection of machined surfaces.

Witnessing mechanical running test

Witnessing strip down inspection and test

Final visual and dimensional inspection

Inspection and Test Plan for Centrifugal PumpThis article, detailing the inspection and test plan for centrifugal pump, provides you information about centrifugal pump inspection and centrifugal pump testing in a manufacturing shop. The draft Inspection and test plan forcentrifugal pumps is provided as well.

The API 610 standard requirements are normally applied for the inspection and test plan in a manufacturing shop.

The witness of some inspection and testing by third party inspectors is mandatory and cannot be waived.

Some others must only be monitored and full witnessing is not necessary; for these items, the inspection man-days etc. depend on the purchaser’s decision. Some prefer stringent monitoring and even assign a resident inspector in the manufacturing shop, and others relay to the quality control system of the manufacturer and assign only a few days for monitoring points.

These are some of the inspection points that need to be witnessed, checked monitored and reviewed by a third party inspector for a centrifugal pump construction.

Inspection and Test Plan for Centrifugal Pump - Important Points

Centrifugal Pump casings to be identified against foundry test certificates and thicknesses checked to conform to approved drawings.

Witnessing hydrostatic test on pump casing

Witnessing Centrifugal pump Impeller run out and dynamic balance tests

Witnessing Centrifugal pump performance test

Witnessing running test on pumps including NPSH where applicable

Strip inspection of pumps on completion of running tests, where specified in data sheet. Wearing surfaces to be checked and recorded. All materials to be checked against test certificates or Vendor`s bill of materials.

Inspection and final dimensional check of pump (including driver, when fitted) mounted on baseplate

Heat run or standard abbreviated tests, as mutually agreed and specified, to be witnessed on electric motor drives.

Inspection and final dimensional check to be carried on motor drivers.

Checking all test certificates

Inspection and Test Plan for Fan and BlowerThe inspection and test plan for fan and blower article provides you information about fan and blower test and fan and blower inspection in manufacturing shop.The draft Inspection and test plan for fan and blower provided as well.

Inspection and Test Plan

The API 673 standard requirements normally are applied for inspection and test plan in manufacturing shop.

The witness of some inspection and test by third party inspector is mandatory and cannot be waived.

Some others must only monitored and fully witnessing is not necessary, for these thing, the inspection man-days etc. depends to the purchaser decision, some prefer stringent monitoring and even assign resident inspector in manufacturing shop and some others relay to quality control system of the manufacture and assign only few days for monitoring points.

These are some of inspection points which need to be witnessed, checked, monitored and reviewed by third party inspector in fan and blower manufacture shop.

Important Points

Checking of fan and blower material certificates and material identification

Welding procedure specification and qualification control as well as control of welder qualifications

Witnessing of fan and blower ducting pneumatic testing

Witnessing of fan and blower impeller dynamic and overspeed testing

Witnessing of fan and blower mechanical running testing

Inspection and Test Plan for Pressure VesselThe inspection and test plan for pressure vessel article provides you information about pressure vessel inspection and pressure vessel test in manufacturing shop. The draft Inspection and test plan for pressure vessel provided as well.

Click here if you like immediately review the Inspection & Test Plan for Pressure Vessel draft sheet.

You may need to review this article in conjunction of following articles:

Pressure Vessel Inspections

The ASME Code Section VIII Div. 1 or 2 requirements normally are applied for inspection and test plan in pressure vessel manufacturing shop.

The witness of some inspection and test by third party inspector or authorized inspector is mandatory and cannot be waived.

Some others can only monitored and fully witnessing are not necessary, for these items, the inspection man-days etc. depends to the purchaser decision, some prefer stringent monitoring and even assign resident inspector in pressure vessel manufacturing shop and some others relay to quality control system of the pressure vessel manufacture and assign only few days for monitoring points.

These are some of inspection points which need to be witnessed, checked monitored and reviewed by third party or ASME authorized inspector.

Inspection and Test Plan for Pressure Vessel - Important Points

All plates need to be identified against mill test certificates at the Vendonr`s works before commencement of fabrication.

Ensuring that welding procedure and welders are qualified and welding electrodes are approved before commencement of fabrication.

Selection of location for spot radiography

Reviewing of radiographs

Witnessing of hydrostatic test

Dimensionally checking and carrying out final internal and external inspection for quality of workmanship.

Checking that all material test certificates and, where applicable, heat treatment charts are in order

If specified witnessing any crack detection, hardness checks, ultrasonic tests etc.

Checking fit-up and chipping-back of welded seams.

Monitoring welding process based WPS

Monitoring all NDE activities

Ensuring that Vendor is familiar with the requirements regarding data books and ensure that the documentation is submitted without any delay.

Checking internal lining of reactors and vessels (if applicable) to specifications.

Checking trays of each diameter and type, mock assembled in the shop. (for process towers)

Checking for interchangeability of parts, where applicable for process towers

Ensuring that any uncommon down comers are fully assembled and offered along with their respective trays. (for process towers)

Inspection and Test Plan for Storage TankThe inspection and test plan for storage tank article provides you information about storage tank inspection and storage tank test in manufacturing shop and construction site.The draft Inspection and test plan for storage tank provided as well.

Inspection and Test Plan

The API 650 for atmospheric above ground storage tank and API 620 for low pressure storage tank requirements normally are applied for inspection and test plan in manufacturing shop as well as site erection.

The witness of some inspection and test by third party inspector is mandatory and cannot be waived.

Some others must only monitored and fully witnessing is not necessary, for these items, the inspection man-days etc. depends to the purchaser decision, some prefer stringent monitoring and even assign resident inspector in manufacturing shop and some others relay to quality control system of the manufacture and assign only few days for monitoring points.

These are some of inspection points which need to be witnessed, checked monitored and reviewed by third party inspector in pressure vessel manufacture shop.

Inspection and Test Plan for Storage Tank - Important Points

Shell plates to be dimensionally checked (including diagonals for squareness) before rolling to curvature.

All shell plates to be inspected and dimensionally checked after rolling to curvature.

Checking material test certificates and ensuring that all shell plates are clearly stamped with the cast and plate number, so that they can be identified against the relevant test certificates.

Checking material test certificates for roof and bottom plates.

Selection of the spot radiographs, DP & MP test as per codes.

Reviewing of radiographs.

On completion of inspection of shell plates ensuring that vendor provide a chart giving all plate numbers, tier by tier.

Inspection of fabrication of all fabricated fittings. This is to include checking of material test certificates also.

Inspection of tank gauging equipment.

For shop fabricated tanks, witnessing hydrostatic tests to applicable standards.

Checking welding material electrodes.

ASME Code Section 8The ASME Code Section 8 is the construction code for pressure vessel and covers design, manufacturing and pressure vessel inspection and testing in the manufacturing shop.

This Code section addresses the mandatory requirements, specific prohibitions, and non-mandatory guidance for Pressure Vessel Materials, design, fabrication, examination, inspection, testing, certification, and pressure relief.

In this article you will learn about the different subsections and guidelines for the use and application of this code.

For ASME Code Section 8 scope and boundaries, review the Pressure Vessel Definition   article.

You may know ASME Code Section 8 has three divisions. Division 1 covers pressure up to 3000 psi, Division 2 has an alternative rule and covers up to 10,000 psi and Division 3 can be used for pressure higher than 10,000 psi.

Hierarchy of Standard

1. Law and Regulation at Location of Installation

Mandatory application of ASME pressure vessel code is determined by rule and regulation at location of installation.

For example, if you are living in the state of Minnesota, the application of ASME Code for construction and stamping is mandatory in your location, but if you are living in the state of South Carolina, it is not mandatory.

2. ASME Boiler and Pressure Vessel Code

The next item in this hierarchy is ASME Code itself; the ASME Code generally is divided into three groups as following:

Group 1: Construction Codes

Some of them are: Section VIII for pressure vessel, Section I for Power Boiler, section III for Nuclear Power Plant and Section IV for heating Boiler

Group 2: Reference Codes

These are the codes which are referenced from construction codes as explained in group 1.

The ASME Section IX for welding and Section V for Non Destructive Testing are in this Group.

For example, ASME Code section VIII for welding requirement such as WPS (Welding Procedure Specification), PQR (Procedure Qualification Record), Welder Performance Qualification, etc. refer you to ASME Section IX.

Group 3: In-Service Codes

These are the codes for in-service inspection after placing the equipment into service.

The ASME Section VI for the heating boiler and Section VII are from this group.

3. National Board Inspection Code(NBIC):

We have assigned a separate article for the NBIC, but as required for this article, the NBIC is making certification for ASME Authorized Inspectors and is also certifying R stamp for Repair services for stamped pressure vessels.

ASME Code Section 8 Content:

See following Fig; it shows ASME Code Section 8 Content:

This section is divided into three Subsections, Mandatory Appendices, and Nonmandatory Appendices.

Subsection A consists of Part UG, covering the general requirements applicable to all pressure vessels.

Subsection B covers specific requirements that are applicable to the various methods used in the fabrication of pressure vessels.

It consists of Parts UW, UF, and UB dealing with welded, forged, and brazed methods, respectively.

Subsection C covers specific requirements applicable to the several classes of materials used in pressure vessel construction.

It consists of Parts UCS, UNF, UHA, UCI, UCL, UCD, UHT, ULW, and ULT dealing with carbon and low alloy steels, nonferrous metals, high alloy steels, cast iron, clad and lined material, cast ductile iron, ferritic steels with properties enhanced by heat treatment, layered construction, and low temperature materials, respectively.

For example, if you need to manufacture a pressure vessel with SA 516 Gr.70 material (Carbon Steel), then you need to meet the marked items in above Fig.

Please note that ASME Code Section 8, does not provide you fabrication tolerances except for misalignment and weld reinforcement.

For example, for nozzle orientation, projection, elevation and other required tolerances there are no values in the code, and you may refer to pressure vessel handbooks for such information.

Review the Pressure Vessel Dimension Inspection   article for such tolerances.

If you review the ASME Forward statement it clearly says “The Code does not address all aspects of construction activities, and those aspects which are not specifically addressed should not be considered prohibited.”

In continuing it says, “The Code is not a handbook and cannot replace education, experience, and the use of engineering judgments.”

For example, ASME Code Section 8 Div 1 in UG-28 mandates all loading to be considered in pressure vessel design, but the method for calculation of all of them has not been addressed.

For example, the formula for wind or earthquakes is not provided in the ASME Code Section 8, and these items and other similar loading considerations need to be designed by using the information provided in the pressure vessel handbooks.

For ASME pressure vessel manufacture certification, as well as Authorized Inspection Agency certification, Review the Pressure Vessel Certificationarticle.

What is the Summary of Important Points in ASME Code Section 8 ?

1. ASME Code Section 8 edition is issued once every 3 years and addenda, once a year – both on July 1st. Edition and addenda become effective on the 1st of January of next year (i.e., 6 months after issue).

2. Thickness of cylindrical shell t = PR/(SE-0.6P) + C

3. Longitudinal weld is more critical because it is subjected to double the stress than Circ. Weld.

4. “Weld joint categories” A, B, C, D – are based on joint locations in the vessel and stress levels encountered. “Weld Types” (type 1, 2, 3, etc.) describe the weld itself.

5. Depths of 2:1 Ellip. and hemisph. heads are D/4 and D/2 respectively. (D= Head diameter.)

6. Weld Joint categories:

Category A:

- All longitudinal welds in shell and nozzles.

- All welds in heads, Hemisph-head to shell weld joint

Category B:

- All circumferential welds in shell and nozzles

- Head to shell joint (other than Hemisph.)

Category C and D are flange welds and nozzle attachment welds respectively.

7. Weld Types:

Type 1: Full penetration welds (Typically Double welded)

Type 2: Welds with backing strip

Type 3: Single welded partial penetration welds

Type 4, 5 and 6: Various Lap welds (rarely used)

8. For full penetration welds (type 1):

Joint efficiency, E = 100%, 85%, 70%

(For the radiography = Full, Spot, Nil respectively)

9. Radiography marking on name plates (typically for Type-1 welds)

RT-1: (E=1) All butt welds – full length radiography

RT-2: (E=1.0) All Cat. A Butt welds Full length, Cat B, spot

RT-3: (E=0.85) Spot radiography of both Cat A and B welds

RT-4: (E=0.7) Partial/No radiography

10. For Welded Heads for E=1, all welds within the head require full length radiography (since they are all Cat. A welds)

11. For seamless heads, E=1, If a) head to shell weld is fully radiographed (if Cat. A), and at least spot radiographed (if Cat. B)

12. Compared to Cylindrical shell, thickness of 2:1 Ellipsoidal head is approx. same as shell, Hemisph. head approx. half and Torisph head is 77% higher.

13. MAWP is calculated for: Working condition (Hot & Corroded). Vessel MAWP is always taken at the Top of the Vessel and is lowest of all part MAWPs adjusted for static pressure.

14. Hydro-Test is Standard Pressure test on Completed Vessels.

Hyd. Test Pr. = 1.3 x MAWP x stress ratio

Insp. Pressure (hydro) = test pr. / 1.3

Min. Test temp. = MDMT + 30°F

Max. Inspection temp. = 120°F

15. Pneumatic test is performed if hydro is not possible due to design or process reasons. Prior to the test, NDT as per UW-50 is mandatory.

Pneumatic test pressure = 1.1 x MAWP x stress ratio, Pressure should be increased in steps (Total 6).

1st step – 50% of test pressure

2nd to 6 step – 10% of test pressure

Insp. Pr. (pneumatic) = test pressure /1.1

16. Pressure gauge range should be about twice the test pressure. However, in any case it shall not be lower than 1.5 times and not higher than 4 times the test pressure.

17. Vessel MAWP represents the maximum safe pressure holding capacity of the vessel. Vessel MAWP is measured at top-most point and is lowest of vessel part MAWPs, adjusted for hydrostatic head.

18. For vertical vessels, hydrostatic pressure caused due to liquid with specific gravity = 1, 1ft of height = 0.43 psig. Or 1 mtr of height = 0.1 Bar

19. Total pressure at any point of Vertical vessel is given by:

Total Pr. = Vessel MAWP + h x 0.433.

(h = height from top in ft.)

20. If part MAWP and elevations are known, Vessel MAWP can be calculated by the deducting hydrostatic head from part MAWP.

21. Ext. Pressure is worked out on basis of Geometric factor A (which depends on L/Do and Do/t ratios) and factor B (depends on A, )

Allowable Ext. Pressure, Pa = 4B/(3(Do/t))

22. For values of A falling to the left of material line in the material chart:

Pa = 2AE/(3(Do/t))

23. Name plate shows The Code stamping, MAWP, design temp., MDMT, and Extent of Radiography.

24. ASME materials (SA) shall be used for code stamped vessel fabrication instead of ASTM (A) materials.

25. Reinforcement pad is not required, if the size of finished opening is (UG 36)

Not exceeding 2-3/8” for all thicknesses of vessel

Not exceeding 3-½”, if vessel thickness is ≤ 3/8’’

26. Reinforcement pad with OD = 2d and thk = vessel thk is always safe (d = diameter of finished opening)

27. Reinforcement limit along vessel wall = 2d

28. Reinforcement limit normal to vessel wall = smaller of 2.5 t or 2.5 tn

29. In reinforcement pad calculations, credit can be taken for area available in shell and nozzle.

30. Fillet weld throat dimension = 0.707 x leg of weld

31. Adequacy of weld sizes shall be checked as required by UW-16. The nozzles construction shall be one of the Code acceptable types.

32. The maximum permitted ovality tolerance (D max – D min) shall not exceed 1% of nominal diameter of vessel. If there is opening, then the tolerance can be increased by 2% x d (d = diameter of opening) if measurement is taken within a distance of ‘d’ from axis of opening.

33. The mismatch tolerances and the maximum allowable weld reinforcement is more strict on longitudinal welds compared to circumferential welds (UW-35).

34. Principle of reinforcement:

Area removed = Area compensated.

Compensation area shall be within reinforcement limits.

35. For use as pressure parts, the plates shall be fully identified. Maximum permitted under tolerance on plates is 0.01” (0.3 mm) or 6% of ordered thickness, whichever is less.

36. All welding (including tack, seal, etc.) shall be done using qualified procedures and welders.

37. Mandatory full radiography in ASME Code Section 8 is required for all welding with thickness exceeding Table UCS-57, and also for lethal service vessels and unfired boilers with Design Pr. More than 50 psig.

38. PWHT is ASME Code Section 8 requirement if thickness exceeds those given in tables UCS-56 (given in notes under the tables). These tables also give min. PWHT temperature and min. holding time (soaking period) based on P-Nos. and thickness respectively.

39. For Furnace PWHT in ASME Code Section 8 , Loading Temperature shall not exceed 800°F, heating rate 400 deg F/hr/inch of thickness, cooling rate 500°F /hr/inch of thickness. Still air cooling permitted below 800°F. During soaking period, temp difference between hottest and coldest part shall not exceed 150°F.

40. Minimum overlap for PWHT in multiple heats = 5 ft.

41. For the ASME Code Section 8 impact test requirement, UCS 66 curve. If MDMT-thickness combination falls on or above the curve, impact testing is exempted. Additional exemptions are given as per UG-20(f) and UCS=68 (c).

Pressure Vessel RT TestThe Pressure Vessel RT Test article provides you with information about Radiography testing in the pressure vessel manufacturing process and related items in pressure vessel inspection.

Do you know what your pressure vessel RT test requirements are? Is full radiography mandatory for your vessel? When is full radiography mandatory? What are the acceptance criteria? What are the RT symbols?

So if you need this information, this article answers all of these questions.

We recommend that you to review this article in conjunction with the ASME Pressure Vessel Joint Efficiencies   article.

Before going into the RT test, we need to know about joint categories. These categories are base on ASME Code Section VIII:

Category A:

All longitudinal welds in shell and nozzles. All welds in heads, Hemisph-head to shell weld joint

Category B:

All circumferential welds in shell and nozzles Head to shell joint (other than Hemisph.)

Category C and D are flange welds and nozzle attachment welds respectively

Longitudinal weld (Category A) is more critical because it is subjected to double the stress than Circ. Weld (Category B) and this the reason in different part of the ASME code, we have stringent rules in category A joints compared to category B joints.

Pressure Vessel RT Test -When We Need to Do a Full Radiography Test?

When one of following conditions is existing, you need to do the full radiography:

1. All butt welds in vessels used to contain a lethal substance2. All butt welds in vessels in which the nominal thickness exceeds specified

values3. All butt welds in unfired steam boilers with design pressure > 50 psi4. All category A and D butt welds in a vessel when “Full Radiography” is

optionally selected

As you see, the item numbers 1, 2 and 3 are really mandatory for a full RT test;

But pressure vessel manufacturers can make an optional decision for full radiography in item number 4

Pressure Vessel RT Test - Why do pressure vessel manufacturers want to spent more money for full radiography in item # 4?

Because the joint efficiency in the full radiography condition is 1, the higher joint efficiency in the pressure vessel wall thickness formula causes less wall thickness. The manufacturer might save lots of money with a lower thickness plate material.

But code has given some bonus to manufacturers in item 4, because it is not mandated to do full radiography in all butt welds. Manufacturers can do spot radiography in B and C joints with the same joint efficiency of item 1.

Item number 2 describes thickness limitations. Any pressure vessel material is designated to the specific P. Number by ASME section IX, so there are several tables in ASME Code Section VIII Div. 1 Subsection C, which determine this limitation.

For example, SA 516 material is P Number 1, and needs to be fully radiographed if its thickness is greater than 1.25 of an inch. At the same time, SA 204 material

is P Number 3 and needs to be fully radiographed if the thickness is greater than 0.75 of an inch.

Pressure Vessel RT Test - Is Acceptance Criteria in Full Radiography or in Spot Radiography More Stringent?

Acceptance criteria for welding defects in full radiography is stringent. These criteria are stated in UW-51 and UW-52 in ASME Code Section VIII Div. 1

It means there is a defect if interpreted based on the full radiography criteria in UW-51, and it might be rejected, but if it is interpreted by the spot radiography criteria in UW-52, it might be accepted.

Pressure Vessel RT Test - What is the Important Spot Radiography Requirement?

One spot shall be examined on each vessel for each 50 ft. increment

For each increment of weld to be examined, a sufficient number of spot radiographs will be taken to examine the welding of each welder or welding operator

Each spot examination will be made as soon as practicable after the completion of the increment of weld to be examined

The location of the spot shall be chosen by the Inspector after the completion of the increment of welding to be examined

Pressure Vessel RT Test - Radiographic Personnel Qualification:

The radiographic personnel need to be certified by the pressure vessel manufacturer according to their written practice.

Holding the ASNT Radiographic certificate is not enough

In fact, SNT-TC-1A can be used as a guideline for manufacturers to establish their written practice for qualification and certification of their personnel.

Radiographic Examination Procedure and method

ASME Code Section VIII Div 1 mandates that all tests shall be done based on ASME Code Section V, article number 2.