Bolted flange joints are subjected to external bending moments in addition to the internal pressure in the pipeline,and the deformation and cornering caused by external bending moments are usually the main cause of the sealing failure of the flange joints.In order to study the sealing performance of the double wedge wedge flange joint under the action of the external bending moment,the ABAQUS was utilized to calculate the sealing performance of lightly double wedge angle ring gasket joint under the bending moment.The results show that the stress of the gasket is unevenly distributed in the circumferential direction by the action of the bending moment.With the increasing of the bending moment,the maximum contact stress of the masterslave sealing surfaces is increased,the effective sealing width of master surface is obviously increased,and the effective sealing width of slave surface is firstly decreased slightly and then increased.With the increasing of bending moment,the angle of the flange is also increased,the maximum deflection angle is about 0.005 degrees,it was lower than the 03 degrees required in ASME standard criteria.According to the JB4732,the lightly double wedge angle ring gasket joints are safety under the service conditions.