Further Experiments on the Sealing Mechanism of a Synthetic Rubber Lip Type Seal Operating on a Rotating Shaft

The paper shows that a seal of the type referred to operates under hydrodynamic lubrication conditions with a liquid film thickness of obout 0·5 μm. Contact angles of oil against rubber and steel are measured, and it is also shown by experiments with capillaries how a meniscus may be turned inside out to resist pressure. The conclusion is that the liquid film is prevented from leaking by the surface tension of the liquid itself.