huangyhg

ansi ansi b16.5 - 1968 edition
i am looking for someone who has the 1968 edition of b16.5 to let me know what requirements were included, if any, for valve closure or valve seat leakage hydrostatic testing. would really appreciate a fax of the applicable page(s). fax is 205-992-5002. thanks in advance.
tlpchris,
ansi b 16.5 is for pipe flanges and flanged fittings.
for testing of valves please refer api 598.
nrp
i am aware that b16.5 applies to flanges and flanged fittings but some of the earlier editions and addenda between 1968 and 1973 added requirements for valve closure testing and stem seal leakage. later these requirements were moved to b16.34 and other standards and codes have added similar requirements.
i have found a 1968 edition of b16.5 and am now looking for the addenda to it if anyone has them.
16.5-68 and before did not cover valve seat testing, just shell tests at 1.5 the 100f rating (paragraph 8). valve manufacturers developed separately a standard through the manufacturers standardization society of the valves and fitting industry to deal with seat tests. this document was mss sp-61 and was originally issued in 1961. its scope was shell and seat closure pressure testing of steel valves designed and made of material to merit the ratings established by b16.5 (and later 16.34). the acceptance criteria was 10cc/hr per inch nominal valve size at a pressure of 1.1 the 100f rating. test times varied by size. note that 16.5-68 did not refer sp-61.
as part of the progression to bring better standarization (ansi ) of valves, 16.5-73 became the standard for flanged end valves and 16.34-73 was for buttwelding end valves. both had seat test requirments, but left the closure tightness requirements to the user, although they did specify testing the seat at 1.1 100f rating. (this requirment and limitation is still in 16.34.) hence the user could use sp-61 or api-598 mentioned above or whatever they wanted. i have seen specifications that invoked sp-61, but used 0.2 cc/hr per inch diameter. they were used for containment isolation valves at a nuclear plant where leakage needs to be optimally minimal.

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