api_510_ptr_7

of 3

DAILY POINTS TO RECALL (DAY 7)

C:\Users\user\Desktop\PV\API 510\API 510 Course - Integrated Training\API 510 Integrated Training - Daily Points To

Recall\API_510_PTR_7.doc 6/19/2014 / 5:19:25 PM / NCD

1. Local PWHT may be substituted for 360-degree banding if:

a. Original PWHT was not due to service requirement b. Effects of Local strains/distortions are considered c. Pre-heat & maintainance of 300 deg. F during welding d. PWHT temp is maintained beyond the weld upto twice base

metal thickness e. Heat is applied to any nozzles /attachments within PWHT area.

2. For repairs of following :

a. Cracks: By preparing V or U-shaped groove and depositing weld metal

Cracks at area of stress concentrations (i.e., nozzle welds) shall not be repaired without consulting the pressure vessel engineer.

b. Localized corroded area: By weld deposit. Low strength electrodes may be used if thickness of deposit is increased by ratio of B.M. strength to W.M. strength and Depth of deposit does not exceed half of thickness Increased thickness is blended with 3:1 taper

3. For repair welds, the weld preparation before welding, and the

completed weld shall be checked by PT or MT. Additionally, the butt-welds shall be radiographed by the rules of original Code of construction (depending on joint efficiency).

4. The carbon and alloy steel materials used in making repairs and

alterations shall not have carbon content over 0.35%. 5. Pressure test is required after repair/alterations, if authorised

inspector thinks it necessary. Pressure test is normally required after alteration.

6. Insert patches must be with full penetration welds. Fillet patches

shall be approved by P.V. Engineer. Normally, a fillet patch equivalent to reinforced opening is okay.

of 3




7. Normally, temporary repairs are replaced by permanent repairs at next available maintenance opportunity. But temporary repairs can remain for longer period if approved by P.V. engineer.

8. Non-penetrating nozzles (including pipe caps) are accepted method

of long term repairs for other than cracks. 9. Full encircle lap band is considered as long term repair for other

than cracks. 10. Full encircle lap band is considered as long term repair for other

than cracks.

11. Re-rating calculations shall be done by pressure vessel engineer, and the inspector shall oversee the new stamping or New name plate showing rerating (new MAWP, temp.) is attached to vessel.

12. Procedure qualifications give suitability of weld for required

mechanical properties (i.e., strength, ductility), while performance qualifications show ability of the welder to make sound weld.

13. Tension test gives tensil value, while bend test shows ductility and

soundness. Radiography also indicates soundness. Thus, Procedure Qualification : by Tension test + Bend test Performance Qualification: by Bend test or Radiography

14. Tensile test for procedure qualification is passed if failure is in:

a. Weld metal at strength>= Base metal SMTS or b. Base metal at strength>= 95% of base metal SMTS.

15. Bend test crack shall not exceed 1/8 in any direction. Radiography

criteria are stricter than radiography for job.

16. P-numbers represent parent metal classification of similar composition and properties, i.e., similar strength and ductility.

F-numbers give similar usability aspects of filler material. A-numbers give similar chem. comp. In As welded condition.

of 3




17. Essential variables (EV), if changed require new procedure qualification. Non-essential variables (NEV) may be changed without new procedure qualification.

18. Supplementary essential variables (SEV) are considered as (EV)

only if there is impact strength requirement. Otherwise they are non- essential variables.

19. EV and SEV are included in PQR document. EV, SEV and NEV are

included in WPS document.

20. PQR gives data used in PQR test and test results, and cannot be revised.

21. WPS gives parameters to be used in production job, and must be

within ranges qualified by the PQR test.

22. WPS may be revised within the EVs qualified. The NEVs can always be revised without affecting validity of PQR.

23. For performance, 1G is flat, 2G is horizontal, 3G is vertical and 4G

is overhead position. Pipe 5G qualifies 1G, 3G and 4G, but pipe 6G qualifies all positions.

24. Welder who welds test coupon for procedure qualification test in

certain position also qualifies for performance in that position if procedure Qualification was OK

25. Performance Qualification of welder is affected if he has not welded

with that process for last 6 months. 26. Inspector can revoke performance qualification if welder is

repeatedly unable to produce satisfactory welds meeting the requirements.

------------------------------------------End------------------------------------

api_510_ptr_7

Documents