Mechanical seal face materials

Abstract

Mechanical seal face materials are described with an explanation of the properties affecting performance and the significance of surface texture including bi-Gaussian surface statistics. Aspects of seal behaviour attributable to face materials are discussed in detail, including random fluctuations of friction and thermal excursions. Boundary lubrication mechanisms of carbon-graphites and other ceramics are described. The role of tribolayers and transfer layers is highlighted. Failure modes are discussed including structural fracture, surface crazing, pitting and scoring, blistering, solids deposition and ‘squeal’ (‘ringing’). Many references are given.