Installation Pressure test

[rika kose]

What is the standard way to perform a pressure test?

A new installation has been made with all the instruments installed.
Now we need to do the pressure test on the new installation.
System design pressure is 6 barg e.g. will be tested with 9 barg(hydro)and follow the API/ISO.

All the instruments's design pressure is 6 barg that will be dismantled during the test,and put them back afterwards.
The nozzles will be closed with blinded flanges in the test.

Here is the question, all the flanges/connections for the instruments are not actually tested under pressure.

And do we need to perform a leaking test after the instruments are installed?

What is the normal way?

 

[LittleInch]

As you describe.

Test the pipe for strength at hydrostatic design pressure, then test the instrument connections and items not able to handle the test pressure for leaks at design pressure where there is isolation between it and the main process pipe.

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

 

[Bazinga]

Sometimes depends on client requirements. Usually following hydro, you may do a low pressure nitrogen test and potentially a high pressure nitrogen test depending on the risk appetite before introducing hazardous chemicals or gasses. What code is your piping designed to, have you consulted that? Note that leak testing generally done to check flange and valve integrity and is not a strength test (which is what your hydro is for).

 

[rika kose]

Thanks for the info.

 

[BEMPE16524]

you are talking more towards piping system internal hydro pressure test.
need to install relief valve somewhere at higher point of your system as there maybe air trap inside the line.
make sure your flushing point is at the very lowest point. and yes, you need to flush the line before real test. client normally insist this to remove all the debris.
also, make sure all your flange connection is properly fastened. had some issue with the plastic cap of the valves were not remove during installation before.

fyi: there is also external hydro pressure test for special equipment normally for subsea application.

R.Efendy

 

[rika kose]

Thanks for the sharing.