Pipeline pressure testing issues
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There is a stainless steel pipeline, and since there is no exhaust point at the higher elevation, it’s very difficult to carry out pressure testing using water pressure. Is it possible to use high-pressure nitrogen for the pressure testing instead? Thank you
When conducting gas pressure testing, please follow the relevant standards; the pressure must not exceed the specified value, as indicated in the corresponding acceptance criteria
The pressure testing of pipeline systems should be carried out using liquid. When hydraulic testing is difficult, pneumatic testing can be used as an alternative, provided that the following conditions are met and safety measures approved by the technical supervisor of the construction party are in place: a) Pipeline systems with a nominal diameter of 300 mm or less and a test pressure of 1.6 MPa or less; b) Pipeline systems with a nominal diameter greater than 300 mm and a test pressure of 0.6 MPa or less; c) Components made of brittle materials cannot be used in pneumatic testing of pipeline systems unless they have passed hydraulic testing first; d) For pipeline systems that do not meet the conditions specified in points a and b and for which pneumatic testing is necessary as an alternative, all of their weld joints must pass non-destructive testing
What is stated above refers to the requirements of one standard only; various standards have different provisions, and the use of gas pressure is strictly prohibited for brittle materials