Codes and Standards for leak testing valves

SOURCE
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QUESTION
What industry codes and standards are used for leak testing of valves?
Any information is helpful along with any links to informative sites.

REPLIES

cliff6361
There are many standards on the street that outline the testing requirements for pressure testing valves and other pressure retention devices. The key is the purchaser of valves. He/She should have knowledge of these standards and specify what it is he/she will accept.

The basic industry standards are:

ASME B16.34 (Pressure and Temperature ratings and test pressure rules)
MSS SP 61 (Good step by step guide to use to develop procedures from and provides good quantitative seat leakage acceptance)
API 598 (Provides test pressure, test sequence, hold times and seat leakage acceptance)
API 6A and D (Similar to all of the above)

Other standards will reference the above or outline testing by adding to the basic requirements as outlined in the above standards.

All above standards require each organization performing pressure testing formulat and write their own test procedures to meet the stated requirements.

One pit fall to avoid is trying to classify standard on-off valve seat leakage is to specify a Classes as defined in ANSI/FCI 70.1 standard. This standard provides test methods and expected leakage rates applcable to control valves. If one takes the time to read and understand this standard they will find there is no class that provides zero leakage but many will argue different.

“If one takes the time to read and understand this standard they will find there is no class that provides zero leakage but many will argue different.”

All valves will leak…eventually. All seals can wear with use, or corrode/erode due to fluid exposure, and/or deposits can form on the seals preventing proper shut-off sealing. Any leak test is only good for the valve in the condition (as built, as refurbished, etc.) that it was tested in. Very few manufacturers will warranty their valves against leakage past a certain amount of time, depending on the service type expected.