MULTIPOSITION DOWNHOLE VALVE Russian patent published in 1995 - IPC

FIELD: producing industry. SUBSTANCE: multiposition downhole valve has hollow body with channels, flexible member in form of bellows installed in body upper part and forms compressed gas chamber together with it, rod with shoulder rigidly connected with its upper end to bellows and member resisting motion of rod. Made on outer generating line of body is groove radial passages accommodating balls interacting, from one side, with flexible ring installed above them in groove, and from the other side, with bellows rod. Rod has additional shoulders with the outer diameter of following larger than preceding. EFFECT: higher efficiency. 2 dwg