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Re: [MW:12244] Hydrotest For Existing Pipe Spool

By Materials & Welding
Dear Bonardo,

You could test the existing line at 1,5 times the MOP of the line which is mostly acceptable practice as stated in ASME 31.3

Regards.

J.N.Murthy

On Mon, Aug 15, 2011 at 2:50 PM, Richard Napitupulu <bonardo.napitupulu@googlemail.com> wrote:
 
Guys :
I Planned to replace a flange due to heavy corroded, after checking the remaining thickness of existing pipe spool we calculate that the remaining MAWP is 900 Psi, whilst MOP of this line is only 100 psi.
 
My question is do we need to hydro test up to 1.5 MAWP which is 1300 Psi or we can lowered the pressure.
 
PS : I recall to read some article (or maybe code) that states for piping operating at not more than 10 % of its design pressure than we can waive the hydro requirement and do RT or UT instead.
 
Thanks
Bonardo
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