The Research Of Safety Issues On PE Pipe Transporting CBM Under Traffic Loads

The background is from Jun Lian blocks project. In this project, Polyethylene pipe （PEpipe）is adopted to transport CBM. It is because PE pipe’s lifespan, corrosion resistance,flexibility, withstand earthquakes are superior. However, it also has some disadvantages.Polyethylene pipe is affected easily by the ultraviolet. What’s more, Mechanical strength ofPE pipe is lower than that of steel. PE pipe is easy to damage. As a result, the coal bedmethane leaks. In this project, some important areas are along the pipeline, for example,school, reservoirs, cottages and etc, which are needed to be protected extremely. Once theCMB leaking, fire and explosion accidents may occur, it will cause great personal andproperty damage, which have a very bad impact on society.The destruction reason of pipeline failure is that its withstand loads is greater thancarrying capacity. In this project, the main load of the buried PE pipeline is traffic load, soilpressure and pressure inside. In this paper, ANSYS software is used to establish the finiteelement model of buried PE pipeline. According to the simulation results, the failurecondition of PE pipeline is analyzed. The impact range of CMB leakage is calculated. Severalsafety measures are proposed, including controlling self safety of PE pipeline, controllingsafety distance and project management measures. The main contents are as the following:（1） ANSYS software was applied to build FEM model of the buried PE pipeline. Thestress and displacement distribution of the pipeline are obtained, and the influence ofdifferent traffic loads on the mechanical properties of the pipelines is studied. The security ofPE pipe is analyzed.（2） The impact range of the typical pipeline coal seam gas leakage accident iscalculated respectively based on the accident consequence method and risk-based method.（3） According to the results of the calculation, the safety measures are analyzed.