Analysis on Sealing and Deformation of Exhaust Valve Housing of Marine Diesel Engine

MAN Diesel's 6S50MC-C disel is a two-stroke marine diesel engine. Preload of the exhaust valve component is applied in four bolts. The preload of bolts can improve the fatigue strength of the exhaust component. In addition, the bolt pretension ensure the sealing in the maximum firing pressure. Using of simulation method, the displacement and deformation of exhaust valve component are analyzed when the maximum firing pressure and preload are applied. By analysis of the deformation of the exhaust valve housing under different preload force, the deformation of exhaust valve housing increase with the increaseing of preload. The maximum total deformation is 0.40mm in the preload of 720KN. The maximum deformation occurs in the region near the bolt in the side of exhaust gas outlet. The deformation in the direction of Y-axis of exhaust valve housing is along the Y-axis opposite direction when the preload is greater than 540KN. This indicates that the exhaust valve seal well. The sealing and deformation of the exhaust valve component meets the desgin requirement.