Inspection frequencies of PSVs

[arcpro]

Which code defines the inspection frequencies of PSVs operating on different services and at different conditions?

[ashfaqanwer]

ASME or API does not define inspection frequencies of PSVs except in ASME VII for power boiler where it mentions from 06 months to 24 months; some guidelines are given in API 14C also for offshore platforms where it recommends annual inspection for all PSVs.
Inspection personnel in Petrochemical industries define these inspection frequencies based upon their experience, history of PSV, type of inspection made and failure rate.
The best practice is to apply RBI (Risk based inspection) and then define the inspection frequencies.
See API 580 & 581.

[arcpro]

Thanks.

[ashfaqanwer]

Arcpro,
Also see Sec. 6.4 of API 576 where it mentions the maximum interval not to be exceeded by 10 years and actual interval shall be determined based upon the performance of valve in the particular services concerned.
Moreover, in Sec. 6.6 of API 510, inspection interval of pressure relief devices for pressure vessels in typical services shall not exceed 05 years unless documented risk assessment indicates that a longer interval is acceptable. For clean, non-corrosive fluids, a maximum of 10 years interval can be set between inspections.

[nnreddy]

Dear Forum Member,

API RBI has already PSV Module.You can use RBI Methodology to determine the inspection frequency which will depend upon the following factors.
1.Valve material construction.
2.Design temperature and pressure
3.Type of service
4.Type of degradation mechanism
5.Probability of Failure
5.Consequence of Failure

Thanks
NNREDDY

[qaisarabbas]

Sharing a very useful & informative presentation, which described a practical approach in setting inspection intervals for new PSVs. Highly Recommended !!

Regards

[ashfaqanwer]

Excellent document Qaisar.
Keep sharing.