Beaded liquid product and method for reducing coefficient of friction

Abstract

A product and method for reducing the coefficient of friction between the inner surface of a support, such as a larger conduit, and the outer surface of a member such as a smaller, inner conduit, disposed in and movable along the support when the latter has horizontal and/or inclined portions. The support may be an open trough or pipe of metal, plastic or other material, and the member to be moved can be of similar materials and can be an electrical cable. The product includes a flowable mixture of a liquid and a plurality of spherical beads typically in the range of 0.005 to 0.040 inch in diameter. The mixture can be pumped in and along the support even though the liquid and the beads have different specific gravities. The beads in the liquid contact both the inner surface of the support and the outer surface of the member to be moved to produce a planar ball bearing effect to minimize the frictional forces between them. Depending upon the specific gravities of the liquid and the beads and upon the rheological characteristics of the mixture, the beads can be near the inner surface of the bottom of the support or can be near the inner surface at the top of the support when the support comprises a pipe and when the mixture fills the pipe. The movement of the inner member along the support can be over horizontal distances and a part of the path can be inclined at least slightly without requiring the mixture to be pumped along the support during the time in which the inner member is moving therethrough. Greater inclination of the support may be accommodated when the mixture is being pumped as the inner member moves therethrough. The beads can be of any hard material, such as any one of the harder plastics, glass or metal.

Dependencies are inferred from the claim text.