Building an analytical model of the lip seal profile

Abstract

The subject of the research is lip seals with an elongated working part for sealing gaps with significant displacements of parts. There are many standard and catalog seals, but the increasing requirements for the maximum strokes of the mating parts require an expansion of the known series. This, in turn, requires more accurate calculations. The main reason for the failure of such seals is the loss of stability of their working part. The variant of action on external pressure seal is considered. This option is the most important, since the operating pressures are more than ten atmospheres, and the seal acts as an element of machine reliability. When pressure is applied from the inside of the seal, it acts as a boot or oil scraper, that is, it does not directly contribute to the reliability of the mechanism. The authors show the derivation of expressions for bending moments in the working part of the seal for the case taken. The scientific novelty lies in the fact that the problem of calculating elliptic integrals in the expression for the bending moment is solved geometrically by representing the working part of the seal in the form of an elliptical ring. The main conclusion is that the existing computational techniques, when supplemented with the found expressions, make it possible to construct a complete lip seal profile of the considered configuration. The practical significance lies in the fact that the construction of profiles according to the considered method can be easily automated using the parameterization tools built into popular CAD systems.