Sealing Characteristics of an Annular Wedge-Shaped Gasket

Abstract

The authors have investigated the sealing characteristics between the surface of an annular wedge-shaped plastic gasket and a smooth seal face of a rigid ball in static contact. The following results were obtained from gas leak tests, calculation of the deformation of a wedge-shaped gasket and a compression test. ( 1 ) In order to seal tightly, a contacting width of a wedge resulting from the plastic deformation of a gasket was required because of the work hardening of the surface irregularities on the gasket. ( 2 ) The contacting width of a wedge increased with a decrease in the conical half-angle of the seal face, θ. Therefore, the linear sealing load, P_c/l, decreased with a decrease in the θ-values. For example, the value of P_c/l at θ=15°was about 0.5 times that at θ=90°. ( 3 ) The recommended values of θ were in the range from 10°to 35°, and it was possible to forecast the P_c/l-values corresponding to that range.