Patent ID: 8646532
Filing Date: 2014-02-11
Classification: E21B

Abstract:
1. A valving device comprising: a tubular with a port; a sleeve slidably sealingly engaged with the tubular between a first position and a second position, the sleeve being configured to occlude the port when in the first position and uncover the port when in the second position, the valving device being configured such that a first pressure inside the tubular does not urge the sleeve toward the second position while a second pressure applied radially outwardly of the tubular and the sleeve urges the sleeve toward the second position, the second pressure exerting a force on the sleeve that is independent of a location of the sleeve relative to the first position and the second position, wherein the valving device is configured such that the first pressure inside the tubular urges the sleeve toward the first position, and wherein the second pressure is a fluid pressure; and a first seal, a second seal and a third seal that are slidably sealingly engaged between the sleeve and the tubular, wherein an opening between the second seal and the third seal fluidically connects a chamber to an inside of the tubular when the sleeve is in at least the first position.