DEVICE FOR PIPE STRING INTERIOR CLOSING Russian patent published in 2006 - IPC E21B33/13 

FIELD: mining, particularly to construct and repair wells, to stimulate gas recovery from productive coal beds.

SUBSTANCE: device comprises cylindrical body with central axial channel, inner annular groove, bridge with through channels and hydraulic chamber. The device also has sealing member with axial channel having conical inner surface. Spacing plug with corresponding outer surface is installed in axial channel of sealing member. Rod is fixedly connected with the spacing plug by radial channel. Breakable member is arranged in the radial channel. Device is provided with annular figured piston, dies and split ring. Sealing member comprises radial slots arranged in upper part thereof. The dies are located in radial slots of sealing member and may cooperate with spacing plug. The figured piston is installed in inner annular body groove and may slide relatively the body and cooperate with the dies. The dies are connected with each other and with figured piston by means of split ring. Hydraulic chamber is formed by inner surface of annular groove made in the body, lower end of the bridge, upper end of figured piston and side rod surface.

EFFECT: simplified structure and increased operational reliability.

2 cl, 3 dwg