Patent ID: 7108071
Filing Date: 2006-09-19
Classification: E21B

Abstract:
1. A wellbore apparatus, comprising: a tubular member defining at least a central bore and at least a first fluid port formed in a wall of the tubular member, wherein the first fluid port provides at least selective fluid communication between the central bore and an ambient environment of the tubular member; a piston valve slidingly disposed in the tubular member; a locking member disposed between the piston valve and the tubular member and adapted to retain the piston valve in a closed and locked position; a pressure-responsive actuating mechanism disposed at least partially on the piston valve; wherein the pressure-responsive actuating mechanism operates to move the piston valve axially relative to the tubular member from a closed position to an open position; and a pressure actuated flow restricting member disposed proximate and over the first fluid port, wherein a position of the flow restricting member is responsive to a direction of flow through the first fluid port.