Hydraulic Seals

Abstract

Leakage is the most common source of complaint with regard to hydraulic machinery. During recent years considerable advances have been made in the prevention of leakage of liquid past moving surfaces. New materials and constructions have come into common use, and there has been a small but valuable amount of research into the action, wear and friction of packings and seals. The object of these papers is to initiate a comprehensive discussion of existing knowledge on the subject, which will perhaps indicate the fields to which future research and development might best be directed. The authors' experience has been mainly in connexion with hydraulic machinery in which oil is the working medium; in this field particularly, the improvement of sealing methods has been very marked. It is hoped that contributors to the discussion will also deal with water, acids, and other liquids, and with the special problems encountered owing to high temperature, corrosion, dirty liquids, etc. As the subject covers a wide field, it has been limited by excluding hydraulic joints. For the purpose of this paper, a hydraulic seal will be defined as one whose function it is to prevent the leakage of liquid between surfaces having relative movement.