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RE: [MW:5786] hydro test

By Materials & Welding
Dear Mr. Selvan,
 
Such a condition does occur when there are temperature variations in the environment. Esp. when you talk of holding the pressure for 6 hours, atmospheric temperature rise leads to expansion of trapped hydro inside the system that would account for the pressure to increase.
We have piping being hydrostatically tested for 24 hours and pressure rise and falls follow a sinusoidal.
 
Regards,

Muhammad Ali

 




 
Date: Tue, 29 Jun 2010 09:18:47 +0000
To: materials-welding@googlegroups.com
Subject: [MW:5782] hydro test
From: centh@rediffmail.com

dear,


please any body explain me. my test pressure is 100bar and holding
time is 6hours.when he do the test, the pressure and temperature is
increase,our supervisor reduce the pressure and maintain the same 100bar
it is correct or what.please tell me.this is station manifold.

regards,
a.s.selvan

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