Abstract: By Changling coal mine gas extraction efficiency, extraction system for the estimation, basedon the gas pressure gradient method, the application of numerical simulation method is the principle ofpressure gradient method to detect pipeline leakage , pipeline segment negative pressure monitoring method adopted for mine gas extraction system are analyzed in leak detection , and has carried on the confirmation to pipeline leak at the scene and maintenance. The results show that using pressure gradient methodto detect the leakage of gas extraction pipeline can effectively and accurately solve the leakage problem ofpipeline, effectively improve the gas extraction efficiency of Changling coal mine, and is of great significance to mine safety and efficient production.

Key words: gas, pipeline of extraction and production, pressure gradient method, pipeline leak detection