Effect of bolts assembly connection process on sealing performance of cylinder

To meet the requirements of sealing performance of composite structures for cylinder, cylinder head, cylinder liner, bolts, cylinder line support and gasket in designing assembly connection process, the material nonlinear of gasket and the elastic interaction of bolts were took into account. Two kinds of different sequence assembly connection process was designed. The composite structure nonlinearity finite element model was established using the nonlinear finite element method, and the correlation between tightening sequence and contact pressure of gasket was studied. A better assembly connection process to meet the sealing performance of composite structure requirements was obtained. The calculated results of residual preloads of bolts agree well with the experimental data. Results show that, the nonlinear finite element method can give accurate assembly connection process simulation of composite structure for cylinder, cylinder head, cylinder liner, bolts, cylinder line support and gasket; under two different tightening sequence conditions. The average residual preload standard deviation is increased with the increase of bolts number tightening. The worst cylinder sealing area appears in the middle of the two bolts in the exhaust side. Two kinds of assembly connection process can meet the requirement of cylinder sealing performance. The worst cylinder sealing area sealing effect is improved.