GEAR FOR INSTALLATION OF CASING LINER IN WELL Russian patent published in 2003 - IPC

FIELD: construction of wells of various assignment, oil and gas wells included, specifically sinking of casing liners into these wells with subsequent cementing. SUBSTANCE: gear has body with windows coupled to transportation rig, funnel with pocket in its internal surface tied up to casing liner. Load-bearing rests fixing body relative to funnel are positioned in pocket of funnel and in windows of body, differential bushing is coupled to body with the aid of sheared members insulating internal space of body from outer space and ensuring possibility of unfixing of body with reference to funnel in case of its axial displacement with simultaneous communication of internal space of body with outer space. In accordance with invention body is made of several components and has external shoulder forming longitudinal ring pocket in external surface of body. Body and internal surface of funnel form ring space communicating with ring pocket. Differential bushing is located in ring space and in ring pocket and has conical surface on part of external side surface. It interacts with internal side surface of load-bearing rests. Rests have conical surfaces for accommodation of conical surface of differential bushing. Body has radial holes hydraulically communicating its internal space with ring space. Windows are cut in external shoulder of body. EFFECT: enhanced functional reliability of gear thanks to reduced time of its setting in working position and to diminished number of actuating elements to drive gear to working position. 5 cl, 2 dwg