Piping system airtightness test
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As the title suggests, how long does it take to maintain a stable pressure during the airtightness test of a piping system? Which specification specifies this clearly? Note that these are standard specifications, not those outlined in plans prepared by individual units or people.
Please refer to (SH3501-2011 Code for Construction and Acceptance of Pipelines for Highly Toxic and Flammable Media in Petrochemical Industries)
Our oil and gas pipeline was airtight for 6 hours at that time
Stopping the pressure for ten minutes is mainly aimed at stabilizing it; if the pressure drops, it indicates that there must be a leak. There is no specific time specified for the inspection – in other words, you can take as much time as you need. Generally, we consider the inspection complete once all valves have been checked
Oh, thanks for the helpful reply. Mainly, I saw on the Internet that some organizations’ plans for airtightness testing specify that the pressure should be maintained for 24 hours, which surprised me; we don’t carry out such tests for that long. Therefore, I’m looking for relevant provisions in the standards to support this approach. Thank you very much
Air-tightness acceptance standard: After maintaining pressure for 24 hours, the average hourly leakage rate of the test system must meet the specified requirements, namely A ≤ 0.5%. Leakage rate formula: A=100(1-P2T1/P1T2)/t % A – average hourly leakage rate, % ； P1 – Pressure at the start of the test, MPaA ； P2 – Pressure at the end of the test, MPaA ； T1 – Temperature at the start of the test, K ； T2 – Temperature at the end of the test, K ； t – test time, hours ；
Stabilization for 24 hours is also possible; some devices are designed to be completely airtight, and all flanges need to be checked. A short time is not sufficient for this, and it depends on the actual circumstances
I happen to need to write about the airtightness test; let’s learn about it*
It’s exactly the information I need; I’ll download and take a look.