Patent ID: 8881802
Filing Date: 2014-11-11
Classification: E21B

Abstract:
1. An apparatus for protecting from debris a component of a running tool disposed within a subterranean tool being run for deployment at a subterranean location, comprising: a running tool mandrel disposed adjacent a component of a subterranean tool to define an annular gap therebetween defining an annular space where components need to be protected from subterranean debris; a self-actuating seal assembly spanning said annular gap for contact with said component during the entire running in from a surface location to the subterranean location except during pressure equalization, said seal assembly comprising a sealing member that allows flow into said annular space as the subterranean tool is run in to equalize initially lower pressure in said annular space with increasing surrounding hydrostatic pressure to reduce differential pressure on the component of the subterranean tool; said annular space, which is closed to flow toward the subterranean location surrounding said mandrel by said seal assembly, is selectively communicated through at least one mandrel wall opening always fully exposed to pressure in said annular space as said seal assembly contacts said component, said opening is covered by a pressure sensitive barrier which is selectively fully opened by defeat of said pressure sensitive barrier automatically responding to differential pressure between pressure at said annular space and the subterranean location surrounding said mandrel at a time when the subterranean tool is run in or pulled out.