Quantitative Research On Risk Acceptance Of Gas Pipeline

Lan Chengyu oil pipeline is China's first long-distance oil pipeline,is the implementation of the western development strategy of the top ten key projects.Lan Chengyu pipeline Qingjiang River through the use of excavation through the way,in the flood erosion,the pipeline depth can not meet the safe operation of pipeline requirements,pipeline operations are threatened.Therefore,the need for the Qingjiang River through the pipeline to transform,after exploration and research,to be in the original cross-section downstream of about 100m,the use of directional drilling through a new way through the pipeline,the new cross-section of the pipeline at both ends of the pipeline and the original pipeline Connected.ANSYS software is used to simulate the physical modeling of the oil pipeline segment through the river channel,which provides important theoretical and technical support for the pipeline crossing technology.This paper first introduces the natural environment and engineering geological conditions of the Qingjiang River.Through the analysis of the engineering scheme,the selection of the crossing scheme is the directional drilling.And then describes the characteristics of directional drilling technology,system composition and construction process,and through the curve and rigs and other equipment were calculated.Secondly,the finite element and ANSYS software are briefly introduced,and the principle of engineering contact problem is analyzed.At the same time,the bending deformation under the self-weight of the pipeline is analyzed theoretically,and the finite element method of the pipeline with different length is simulated and analyzed.It is concluded that the radius of curvature of the pipeline becomes smaller and the trend and index Changes in the law consistent.Then,the finite element simulation model of directional drilling back drag is established by using ANSYS software and APDL language.Finally,the finite element simulation analysis of the different land reclamation angles and different unearthed angles of the pipeline is completed.It is pointed out that under the premise of the rock formation,the equivalent stress and the drag force of the pipeline follow the polynomial law,considering the equivalent stress and the contact stress and so on,and select the small value as far as possible under the construction condition and the excavation angle When the drag value is small.