Abstract:The rubber model of packer was established by the finite element analysis software.The contact stress between rubber and casing and its axial distribution,the change of maximum contact stress with the structural parameters including the inclination angle of the rubber,the subthickness,the rubber height and the friction coefficient,and the effect of different torsion loads on the sealing performance of the rubber tube were analyzed under the single axial load and the combined action of axial and torsional loads.The results show that under the single axial load,the maximum contact stress is decreased firstly and then increased with the increasing of the angle,is increased firstly and then decreased with the increasing of subthickness,is decreased with the increasing of rubber height,and is decreased firstly and then increased with the increasing of friction coefficient.After applying torsional load,the maximum contact stress of the rubber with different subthickness,inclination angle and height is reduced and has a larger fluctuation,and the friction between the contact surfaces of the rubber tube is increased with the increasing of friction coefficient,which accelerates the wear and aging of the rubber tube.The maximum contact stress of the rubber tube fluctuates greatly under different torsion loads,which leads to the unstable sealing performance.Therefore,the torsional load reduces the sealing performance of the rubber tube,results in a greater fluctuation of the maximum contact stress,and increases the instability of the sealing performance of the rubber tube.