The sealing performance of aircraft engine pipeline connection was investigated under the tensile load in two aspects. Firstly

the contact force change of the pipeline connection sealing surface was studied to make a mechanical analysis of the sealing performance

by establishing the equivalent rigid model and the force balance equations of the pipeline connection under tensile load. Secondly

the multi-body contact elastic model of pipeline connection was established and the numerical simulation was made by finite element method(FEM) under the pre-tightening force and tensile load

whilst the contacts with initial penetration were established to realize the implementation of preload. On the basis of the simulation results

this paper made a detailed quantitative analysis of pipeline connection's sealing performance

through investigation of contact forces

contact area and contact stress on the sealing surface.