Stress Analysis And Structure Optimization Of Flexible Pipe Joints

With the continuous development of society and the advancement of science and technology,the drawbacks of traditional pipeline connection methods are gradually emerged.As a new pipe connection method,the clamp type flexible pipe joint begins to stride into the public view due to its various advantages.However,in China,the theoretical researches on such pipe joints are not extensive and in-depth,and the traditional connection methods adopted by users are already ingrained,and it is a long-term and arduous task to fully promote clamp type flexible pipe joint.Therefore,this paper analyzes the stress of clamp-type flexible pipe joints,and puts forward structural improvement optimization suggestions based on the factors such as sealing performance,stress distribution,and joint quality.Firstly,this paper introduces the structure and working principles of the clamp-type flexible pipe joint,the experimental methods of performance inspection,and the classifications of the flexible pipe joint.Then,this paper explains the finite element analysis theory,nonlinear analysis theory and optimization analysis theory involved in the structural optimization.Finally,the stress analysis and structural optimization of clamp-type flexible pipe joints are studied.This paper uses large-scale finite element analysis software ANSYS Workbench to carry out numerical simulation,and proposes an optimization scheme for the shape of the seal ring,the shape of the limiting groove and the size of the pipe joint,and this paper gives the following conclusions:The maximum equivalent stress of the clamp-type flexible pipe joint subjected to tensile load,bending load,internal pressure and moment load occurs on the left and right end of the pipes,and the stress at the limit ring and the limit groove are large,and the stress endured by bolts and seals are small;the optimization of the sealing effect,when the same preload is applied to the pipe joint,the contact pressure between the trapezoidal section seal ring and the end pipe is greater than the oval seal ring and the rectangular seal ring,so the effect of trapezoidal seal ring is optimal;the optimization study of the limiting groove's shape,when the same tensile load and internal pressure plus moment load are applied,the maximum equivalent stress of the elliptical limiting groove is less than the trapezoidal limiting groove and the rectangular limiting groove,so the elliptical limiting groove is the optimal structure;on the basis of national standards,the size of the elliptical groove is optimized,and the optimum dimensions are determined by the quality of the joint and the stress: the thickness of the clamp boss is 30.2mm,the bottom thickness of the groove is 11.942 mm.