PetroStreet

Normally, the practice followed at sites is that the hydrotest is usually carried out after removal check valve's flapper. Currently, this practice is wasting much of our time at a piping modification project. Is this a code requirement to remove flapper of check valve before hydrotest?
Can we undertake hydrotest of a piping system with check valve along with flapper installed in position?

We encountered the same question at our site some months ago.
What we closed after having a discussion with the experts was the pressurization source along with test gauge should be upstream of check valve & if pressure source is downstream, flapper shall be removed.
One more precaution was to release the test pressure after testing from downstream side of check valve.

Looks like appropriate.
Thanks for your reply.

Normally, what I have practiced rather enforced on our construction contractors is to remove the check valves internals or to properly block it in open position, if possible. You may also look into bypassing check valve, where possible.

arcpro has made a good point above, totally agree with him, I would like to add the following statement;
( Components which interfere with filling, venting, draining or
flushing shall not be installed until after line flushing and
pressure testing are completed. These include orifice plates,
flow nozzles, sight glasses, check valves, venturis, positive displacement
and turbine meters and other in-line equipment ).

MOE,
So what do you recommend, removing flapper / check valve and then to test?

Hmmm.... well in my opinion where removal of flapper is not inevitable....one should go for the blocking of flapper in an open position first, its more practical and logical...

Ahsin,
What do you mean by blocking of flapper in open position?

Can we do pneumatic testing to check pipe joint integrity before starting the plant instead of hydrotest?

Yes at places, where it is impractical to carry out hydrostatic test due to one reason or other, code allows you to opt for pneumatic test at 1.3 times design pressure. No issues.