Risk analysis and countermeasures for pigging operation of gas pipelines

Regular pigging operation is required for long-distance gas pipelines to ensure its safe and stable running. Due to flammable and explosive of and natural gas and operation under high-pressure operation of gas pipelines, the pigging operation is very dangerous. Based on the experiences in pigging operation of inland long-distance gas pipelines, this paper summarizes possible risks in pigging operation of gas pipeline, including pig blocking, blowing-by, risks in blind plate operation and valve leakage, self-ignition of sulfide, explosion of natural gas and environmental pollution, and presents countermeasures accordingly. The pigging operation also requires close cooperation between site groups engaging pig receiving and launching, valve chambers along the pipeline route and sound monitoring spots to ensure safe operation of pigging operation.