Risks recognition and control in on-line pigging operation of gas pipeline

On-line pigging operation in long distance gas pipeline is a kind of special pigging operation which uses pipelinenatural gas as the power source for pig's operation under the condition of non-shutdown and non-venting, thus it's highlyrisky. In line with the specific implementation flow of pigging operation and over ten times of field experiences of on-linepigging operation in JiZi Gas Pipeline of Shandong Gas Pipeline Company, risks in the process of pig launching, operatingand receiving are analyzed and the causes of risks are explained in detail, and pertinent risk control measures are proposed.The results from the post risk control indicate that various risk factors are under control, ensuring the smooth pigging in JiZiGas Pipeline without shutdown, which can provide some references to the on-line pigging operation in long distance gaspipeline in the future.