Numerical Simulation And Experiment On Pipes Repair By Steel Sleeve Filled With Epoxy Resin

Pipeline is "artery" in oil and gas transmission, with the increase of the service time, pipeline corrosion is unavoidable. If the situations are serious, pipeline leakage even burst will happen. Therefore, pipeline repair draw much more attention. The present domestic research methods of repair technology by steel sleeve filled with epoxy resin is still in its infancy, so, combine the finite element method and experiment is of great significance.This paper mainly studied the reinforcing effect of the epoxy sleeve and discussed the reinforcing mechanism, the reinforcement need to consider share the load and reduce the bending moments. First, through the compression experiment, we tested the mechanics parameter of the epoxy resin. Second, through the pipe burst experiment, we tested the strain values of defects surface and the steel sleeve, and using finite element simulation to analyze the reinforcing effect of epoxy sleeve.Third, we compared with the test values and the numerical simulation results, verified the accuracy of the finite element model in the paper.Based on the elastic-plastic finite element theory, we respectively simulated and analyzed both ends open pipeline with defect before and after reinforcement, studying the effect of the defect size on the residual strength and further optimizing the epoxy sleeve repair design parameters. The results show that the depth of defects on the influence of pipeline residual strength is greater than the other two directions for the uniform corrosion rectangular defect. The effect of the bubbles in the packing area of epoxy sleeve on reinforcement depends on the size of the bubbles and the location of the bubbles. The thickness of the epoxy layer has little impact on reinforcement and the thickness increase of the steel sleeve in a certain range will enhance reinforcement. The fiber reinforced composite material deposited in the epoxy layer raise the reinforcement slightly, showed that increase the reinforcing layer stiffness increase had little impact to the circumferential stress of the defect, which is in accordance with the reinforcing mechanism discussed in the paper.