Strength Analysis And Safety Assessment Of Special Pipeline Structure

With the large-scale construction of oil and gas pipeline in China,Pipeline structure become more and more complex in case of some special conditions and the demand for the pipeline design department requires higher and higher.Some special pipeline structures such as pipelines in buried crossing road casings,various structural forms of the station pipeline structure are widely used,the strength analysis of these special structures is of practical significance to the project..Based on the basic theory of engineering mechanics,strength and stabilization analysis of pipelines in buried crossing road casings were conducted.The stress failure criteria for both domestic and foreign codes were compared.Analytical and numerical stress calculation methods for pipes in buried crossing road casings under working loads were proposed.Based on the linear buckling theory,a finite element model for critical buckling temperature of pipelines in buried crossing road casings was also established.Effects of common factors on the critical buckling temperature were discussed.A mechanics numerical model of typical station pipeline was also built by nonlinear finite element method.The model was parametric programmed by the APDL language of nonlinear element software ANSYS.Basing on the parametric program,influences of parameters on the mechanics behavior of station pipeline were discussed,including the operating internal pressure,temperature differential,angle of turning and radius of gyration of elbow,and straight length.Design several forms of complex pipeline section structures combining simple pipe section structures with elbows and do strength analysis through finite element method.