Abstract: During increasing throughput in a gas compressor station, problems such as insufficient processing capacity of filtering separation systems and measurement data loss of ultrasonic flowmeters were found. In addition, gas components changed largely due to upstream double-gas source supply, so that accuracy of custody transfer was affected seriously. Based on composition analysis results of gas impurities, a cycloneseparator in the upstream of filter separator is installed, and filtering separation branch is laid out to improve gas purification capacity.In accordance with actual conditions of the station, an online chromatograph on the incoming manifold is installed to deal with the gas component change in order to increase the accuracy of custody transfer. An underground process between the flowmeter and pressure control valve is designed and the impact of throttling noise on the metering is basically eliminated by T-shaped fittings and elbows.