Patent ID: 9567817
Date: 2017-02-14
CPC Classifications: E21B

Claim:
1. An apparatus for reducing pressure in a radial seal on a rotating control device (RCD) at a wellbore, comprising: an inner member housed in the RCD, wherein the inner member has an outer surface; a wear sleeve adjacent to the outer surface of the inner member; a top seal in contact with the wear sleeve; a bottom seal in contact with the wear sleeve; wherein the wear sleeve is be sealed by the top seal and the bottom seal as the inner member rotates in the RCD; and a pressure reduction system mounted with the RCD and configured for pressure communication with wellbore pressure, whereby pressure is applied between the top seal and the bottom seal, the pressure between the seals being higher relative to a pressure above the top seal, and the pressure between the seals being lower relative to a pressure below the bottom seal.