Patent ID: 8636059
Filing Date: 2014-01-28
Classification: E21B

Abstract:
1. A downhole circulating valve comprising: a generally tubular outer housing having a generally axially extending internal passageway, at least one generally longitudinally extending cylindrical circulating passageway formed through at least a portion of the housing, at least one exterior port in fluid communication with the circulating passageway and at least one interior port in fluid communication with the circulating passageway; and at least one seal plug slidably disposed within the circulating passageway, the seal plug including a generally cylindrical plug shell having at least one seal ring on an exterior surface thereof and a generally cylindrical plug pin that is operable to be slidably received in the plug shell to expand the seal ring, the seal plug having a first position wherein the plug pin has not expanded the seal ring and the seal plug is remote from the exterior port and the interior port thereby allowing fluid flow between the exterior port and the interior port through the circulating passageway, a second position wherein the seal plug is between the exterior port and the interior port and the plug pin has not expanded the seal ring and a third position wherein the seal plug is between the exterior port and the interior port and the plug pin is received within the plug shell expanding the seal ring to form a metal-to-metal seal with the circulating passageway, thereby preventing fluid flow between the exterior port and the interior port.