Method to Control Gas Displacement Velocity in Gas PipelineCommissioning

Analysis is made on the data of gas displacement during the commissioning of a gas transmission pipeline and a method for determination of travelling velocity of gas-nitrogen-air section is put forward based on the gas pipeline with inner coating, Meanwhile, a proper pressure at injection point to displace the pipeline of different section length is defined according to preset travelling volisity, and timing adjustment and optmized control are realized so that the purpose for safe displacement is achieved.