Commonly in engineering, every pipe that flow either liquid or gas has to conduct leak test. We divide some responsibilities through leak test.
- Company shall witness and make punch list activity. They give approval and comment if get any discrepancies.
- Contractor shall coordinate line check, punch during Leak test from preparation until execution phase. Directly make order to sub-contractor to take action as long as installation of pipe meets the specification.
- Sub contractor shall execute punch list repair activity, prepare tools to reach close all comments from owner.
- Vendor, in case we conduct leak test use N2, so vendor has to provide Vessel of N2, hose connection, manifold, pressure indicator, pressure test pump, valve, gas evaporator, filter, fitting, and flushing equipment. Check leakage.
Every pressure must monitor and certified as specification from company.
Before leak test will be conducted, considered things are safety and environment. (crew has to use coverall, safety helmet, glasses, glove, ear plug and portable gas detector). Environment notice about surrounded area may accident in there. so list of chemical spill possibility, source of leaks, and so on. Please consider about blow down valve and do not vent for gas hydrocarbon through atmosphere.
Contractor has to consider about spool and connection and also margin of length. screw of flange! I mind if screw has put cap and another flange and blind flange as portable line stop. different case that i follow tproject. we delete flange on nozzle connection of tank due to flange can’t access if any leakage may occur. and connection has to change with butt weld. Owner did wants to put inside flange in in-deck tank. since the line mention in line list has test pressure but since the line has no pressure (drain), we can carry out leak test with margin length of pipe and weld with blind flange, after it we can delete and make clean the edge of pipe.