Pneumatic test in refinery construction

[Kuakoon]

In the refinery construction project, the Instrument Air Line Classification List specifies a pneumatic test at 10 bar.

Please advise on the most appropriate method for this test.

Should we use an air compressor or nitrogen gas?

This line runs throughout the area, with a total length of approximately 400 meters and a pipe size of 6-½ inches.

There are no break flanges along the line, which makes the test setup more challenging.

If you have any recommendations or alternative approaches, I would appreciate your advice so I can discuss it further with the client.

 

[HTURKAK]

This subject discussed within several threads . I will suggest you to look previous threads. When ever i hear pneumatic test , i get nervous. Check with local authorities for the permission and necessary measurements.​

pressure test piping of natural gas 150 Barg by N2 - Pipelines, Piping and Fluid Mechanics engineering

I am worried about the PNEUMATIC TESTING piping of natural gas 150 Barg by N2 or Air because of the many dangers of exploding to person. Detail : PIPE ASTM A671-CC65 CL.22, 24" x STDx 1000 m Please help to recommend for performing this test

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Cost of Hydrostatic and Pneumatic Test - Mechanical engineering general discussion

Hi, currently I am estimating cost of constructing and installation of LPG filling station. And, I want to know the cost/price for doing pneumatic test in LPG piping system and hydrostatic test in fire fighting system. Is there anyone that can provide me the estimation (in US dollar) regarding...

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[LittleInch]

Direct air testing has significant risks associated with it. As this is a TEST, this means it has not been subjected to this pressure before and CAN FAIL.

Hence if this is to be tested this way, you will need to positively isolate the system (i.e. a physical gap or solid spade / blind flange) between your air system and any thing else, then clear the area completely. Many failure have occurred from air test pressure leaking into vessels and tanks unable to cope with the pressure. DO NOT RELY ON VALVES.

An air compressor my be better because it tends to be limited on pressure whereas a N2 bottle can deliver a lot more if the pressure regulator fails. Just get a small one so that over pressure takes a long time to occur and with a 6" line 400m long that's a reasonable volume to fill.

Do the pressure test first then reduce pressure to the leak test pressure before sending people in with soapy water to check for leaks

 

[Dhurjati Sen]

Kuwait National Petroleum Company (and for that there must be many others including Shell DEPs) have pneumatic test procedures which are very good.

 

[John Taylor]

In the refinery construction project, the Instrument Air Line Classification List specifies a pneumatic test at 10 bar.

Please advise on the most appropriate method for this test.

Should we use an air compressor or nitrogen gas?

This line runs throughout the area, with a total length of approximately 400 meters and a pipe size of 6-½ inches.

There are no break flanges along the line, which makes the test setup more challenging.

If you have any recommendations or alternative approaches, I would appreciate your advice so I can discuss it further with the client.

For a pneumatic test at 10 bar on a 400-meter, 6½-inch Instrument Air Line, nitrogen gas is the safer and more suitable choice over compressed air. Nitrogen is dry, inert, and reduces the risk of fire or explosion. Given the line’s length and no break flanges, use a controlled manifold setup with proper gauges. Pressurize slowly, allow for stabilization, and monitor pressure carefully. Ensure safety measures are in place and personnel are cleared during the test.