Pressure test of piping in the cold box
(1) The system adopts air pressure test, the medium is dry and oil-free air. And must be responsible for the package by a dedicated person partition, strict and careful inspection of the leakage of each part, no leakage is allowed.
(2) Before the pressure test, the butt welds of the pipeline should have been checked and qualified, and the valve position holes of all safety valves and automatic valves in the switching process should be blocked with blind plates.
(3) Leak detection can be done with fat-free soapy water or dibutylnaphthalene sodium sulphate solution as a foaming agent (as it has a corrosive effect on aluminium, it should be scrubbed clean with clean hot water at the end of the leak test)
(4) First fill the pressure to 20kPa, and then fill the pressure to 50kPa
(5) Weld leaks shall be properly repaired. (5) The leaking weld must be repaired correctly. Never use tapping or leak-proofing agents (cryogenic glue) for repair. The repair weld is then checked with a pressure of 50kPa. Internal compression device: External compression device
Pressure test of piping outside the cold box
(1) Except for the pressure test of the water system, which can be carried out with water, the rest of the system should be carried out according to the above requirements. After the pressure test, remove the blind plate for the test pressure, and then fit a new gasket to tighten the bolt and nut.
(2) After removing the blind plate. A gas tightness test is required. The test pressure is the working pressure.
Dear air separation adopts small air separation unit pipeline installation before the strict pressure test to ensure the completion of the installation.
