Testing a valve with RTJ 1

[Thirlmere]

Hi guys, just wondering if its ok to test a class 2500 plug valve with an RTJ design flange using a blind flange with an "O" ring groove machined in to give us the seal.

Thanks

 

[gerhardl]

This is a general opinion, not actually checked with any standard description for leakage test, as I presume you have already checked the full text, without finding any details.

Any valve checked for leakage with a blind flange should be checked with a blindflange suited the exact counterflange on the valve. An O-ring is dimensioned to change form by flange pressure to fill the exact form necessary to give full tightening between the two flanges.

If your valves' O-ring flange is smooth, and requires a smooth counterflange without any countergrove or tongue it is OK to test against a suitable smooth flange. If the flange requires a counterflange with tongue or have a special form, you could either risk a permanent disfiguring or weakening of the O-ring, and/or leakage.

This is especially important by high-pressure tests. The risk for disfiguration is of course lower if you test in the lower presure range for your valve. Any O-ring must be in material and dimension giving the correct form and resistance required, and when replaced it must be changed with materials and construction equal or giving equal thightening properties.

 

[Thirlmere]

Thanks for the reply, would be awesome if it was in plain english though

 

[vpl]

Gerhardl, Next time you should write it in Norwegian for him ...

Patricia Lougheed

******

Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of the Eng-Tips Forums.

 

[gerhardl]

Thanks Patricia, I do appreciate your remark! We foreigners do often have a problems with the 'Kings English' (The presidents' American????), and I can also see the reason for the original remark from Thirlmere .

As long as the message comes through we should all be happy!

 

[Burdy]

If its hydraulic testing your risk is low, if gas then just don't do it the Risk is too high.