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Re: [MW:35689] Clarification on Pressure Drop During Hydro test Due to Temperature Variation

By Materials & Welding
With increase in temperature fluid expands causing pressure increase .  Also significant pressure variation can be expected when fluid is compressible. Can you please specify about  fluid and test temperature?

On Sat, 7 Jun 2025 at 18:12, Kannayeram Gnanapandithan <kgpandithan@gmail.com> wrote:
Pressure Directly proportional to Temperature when Volume is constant 

THANKS & BEST REGARDS,
KG.PANDITHAN, BE, IWE,  CSWIP 3.1,
ISO 9712 Level 2 in VT,
ASNT-Level II in PT,MT,RT & UT,
LA ISO 9001-2015, ISO 3834, EN 15085, 
International Welding Engineer. 
CONSULTANT-WELDING & QUALITY
Mobile no: +919940739349

On Sat, 7 Jun 2025, 10:36 Vinoth Kanna, <gvinoth43@gmail.com> wrote:

Dear Experts,

During a hydrostatic test, we observed a gradual pressure drop of approximately 0.7 bar in a 2-inch pipe with a length of 31 meters. The test pressure was 12.5 bar. This issue has occurred in multiple tests.

We request your explanation regarding the relationship between pressure and temperature, and how temperature variations can affect hydrotest results.Also, we seek clarification on the acceptable pressure drop limits considering potential temperature changes during the test.

Thank you for your support.


Regards,

Vinoth G





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