Finite Element Simulation of Mechanical Behaviors and Seal Performance of Oil Seal Plug.

Abstract

A hydraulic machine is usually composed of many components. Oil seal plugs, which are used for preventing oil leakage, are one of the most important machine elements among them. Currently, it is sometimes reported that with increase of operating oil pressure, leakage occurs from the regions where oil seal plugs are attached. The configuration of oil seal plug is quite similar to that of ordinary hexagon bolt, except that the grip length and the height of head are particularly small. It is, therefore, anticipated that the specific shape of oil seal plug may yield characteristics significantly different from those of hexagon bolts. Despite its importance, however, it seems likely that mechanical behaviors of oil seal plug have not been investigated so far. In this paper, such fundamental characteristics of oil seal plug as the amounts of tightening torque required for desired clamping force and distributions of contact pressure relating to seal performance are analyzed using finite element method which deals with multi-body elastic contact problem. It is also examined how the rapid rising of oil pressure applied affects the variations of contact pressure with time and whether it might cause the oil leakage, using one-dimensional spring element together with the integration scheme proposed by Newmark.