Hydrotest Manifold Requirement

[Beginner - Inspector]

Dear Gents

Please kindly advise which standard demands for hydro test manifold ? why is it mandatory ?
Also advise which valve is most suitable for pressure test manifold ?

Regards
Viswa Manoj

 

[LittleInch]

I would go for ASME B31.3.

And make the design pressure of the manifold the test pressure of the item you're testing.

Valve? A suitable one designed for the pressure you have. Very vague question.

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

 

[Beginner - Inspector]

Dear LittleInch

I just wanna know without a Manifold whether pressure test can be done ?

In the Case of Valve I just need advise , which is the best, ball valve or gate valve?

Which valve can be considered as bleed valve ?

 

[LittleInch]

Viswa.

This is a professional engineering site. Please use proper words / English. It takes the same time to write "I would like to know..." as it does to write " I just wanna know..." The former is much more polite and proper.

I don't know the answer to your question as it depends on many things in don't know and you haven't told anyone, but it is common to use a manifold so that it can be remote from the test location, but has room for test gauges, valves etc.

For isolation purposes either ball or gate is good.

For bleed you need a needle valve or globe valve, not a ball or gate.

Normally the experienced contractor has all this already - Is this your first time?

what is it for - piping or a pipeline? Pressure? Location?

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

 

[Strook]

Hi Vis,

ASME B31.3 would be a good place to start. I'd recommend that you rate the pressure capacity of your manifold to a pressure lower than the test pressure, not equal to the test pressure. This is common practice amongst pressure piping and vessel codes. Note also that test pressure is not the same as burst pressure.

For the forum to suggest a suitable ratio between your hydrostatic test pressure and the manifold's design pressure would require more information.

Tom

 

[LittleInch]

Mechkoo,

Why would you do this?

This is not common practice AFAIK. If you think it's a code thing then quote the code and section.

I would always state a ratio of 1, I.e. the same.



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

 

[EdStainless]

What pressures? For over 5ksi we used disc valves because ball and plug valves would only last a few cycles. At high pressures your bleed valves will need full Stellite trim to resist cavitation. This isn't trivial.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

 

[Strook]

LittleInch,

After re-reading, I understand this equipment is for the hydrotesting of other equipment. Yes, design pressure should equal max. pressure being used to test other equipment, or possibly even 5-10% above expected max. operating pressure.

Tom