Commissioning Technology of Long-distance Gas Transmission Pipeline

The paper introduces common dewatering methods of long—distance gas transmission pipelines at home and abroad.Commissioning technology and requirements of gas pipeline are described from four aspects of implement program／field preparation，dewatering，gas displacement and pressure boosting.Primary factors influencing on drying time are analyzed.Estimation method for drying period，flowrate and gas volume accumulation needed in gas displacement are given.