Performance Research Of Rubber Barrel Of Stopper In Deep Water Pipeline

Pipeline transportation is currently the most mature way of marine resource transmission.Because of the complexity of the working conditions,pipelines are prone to damage.Therefore,the research for deep water pipeline maintenance equipment is of great significance.As the main emergency repair equipment for submarine pipelines,deep water pipeline stopper,indepth study of its performance will help to break foreign technical containment.It can also provide security for marine oil and gas transportation,which is conducive to the development of the marine economy and the protection of the marine environment.This paper focuses on the sealing device of the deep water pipeline stopper,and analyzes the working principle and failure mode of the rubber barrel.On the basis of the existing research,through the establishment of differential equations for the different deformation stages of the rubber barrel,the mechanical properties of the rubber barrel are analyzed,the distribution of contact stress and shear stress of the rubber barrel is clarified,and the evaluation model of the sealing performance and strength of the rubber barrel is established.In order to avoid the sealing failure caused by the working temperature exceeding the applicable range of the rubber barrel material nitrile rubber(NBR),it is proposed to use the fluorine rubber(FKM)with a higher applicable temperature as the rubber barrel material.According to the uniaxial tensile test of the two materials,the most suitable hyperelastic constitutive models and parameters of the two materials at the temperature of 25℃,40℃,55℃,70℃,85℃and 100℃are obtained.And the accuracy of the parameters is verified by simulation.It is proposed to use the sealing performance evaluation coefficient to express the sealing performance.The contact stress,Mises stress and shear stress of the two materials at different temperatures are obtained through simulation,Applicability of the FKM rubber barrel at 150℃ is proved,and the influence of temperature on the sealing performance and strength of the two material rubber barrels is analyzed.Based on fracture mechanics and FE-SAFE software,the fatigue life of rubber tensile specimens is calculated and compared with the fatigue test results to verify the feasibility of simulation.According to the mechanical simulation results of the rubber barrel,the fatigue life and damage location are predicted.The fatigue simulation results are compared with the mechanical simulation results and the rubber barrel that has damaged under actual working conditions.The influence of temperature on the fatigue performance of two material rubber barrels is analyzed.Combining the working conditions of the rubber barrel,using normal temperature seawater and high temperature oil as the liquid medium,the two rubber materials are tested for liquid corrosion resistance.The macroscopic and microscopic structures of the two materials after swelling in different liquid media are measured through experiments,the advantages and disadvantages of the liquid corrosion resistance of the two materials are compared,and the prime causes of the changes are analyzed.According to the relationship between the hardness of the rubber barrel and the sealing performance,the influence of the liquid medium on the performance of the rubber barrel under working conditions is analyzed.The content of this paper establishes the evaluation method for the sealing performance and strength of the rubber barrel of the stopper,and provides a reference for the application of the rubber barrel material under high temperature conditions.