Hydrostatic shell test pressure

[Newbie]

Greetings!

Referring to API 6D, para. 9.3: "the test pressure shall be 1.5 or more times the pressure rating determined in accordance with 5.2 for material at 100 deg F (38 deg C)"; if I am to run a pressure test on a 2" 150 Ball Valve, A105 material with 150 deg C pressure rating, which gives me a working pressure of 17.7 bar (ASME B16.34), will my pressure test be 1.5 x 17.7 bar or 1.5 x 19.6 bar (which is the pressure rating at 38 deg C) ?

Recently we have been audited by a client and they said that our test pressure is wrong because we used the "1.5 x 19.6 bar" instead of "1.5 x 17.7 bar". Now I am confused. Kindly help.

Thanks!

 

[LittleInch]

Your client is confused not you. The wording is clear and this is the practice. Simply quote what you have said here.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Newbie]

Hi LittleInch,

Yes, was in need of assurance!

Thanks!

 

[ghahramantaps]

hi
it is such a common problem in valves
we handled this problem in شیرآلات قهرمان very easy

 

[Gilmiril]

Ask your client if you can elect to use the 538C pressure rating instead--that way you can test at 1.5 x 1.4 bar or just 2.1 bar!

Your client clearly does not understand ASME pressure classes, which have different pressure ratings depending on the operating temperature. You may need to explain that because the hydrostatic shell test is done at room temperature, it needs to be based on the room-temperature pressure rating.

By the way, the pressure rating for Class 150 with A105 material at 150C is actually 15.8 bar and not 17.7 bar (that's for 100C).

 

[Newbie]

Hi Gilmiril,

Thanks for the correction!

Thanks!