DEVICE FOR INSTALLATION OF PATCH IN CASING STRING Russian patent published in 2000 - IPC

FIELD: equipment for well repairs, particularly, devices for installation of corrugated metal patches for reconditioning of tightness of casing strings of oil, water and gas wells. SUBSTANCE: device consists of circulation valve, movable force pusher including cylinder, piston and hollow rod. Located on core with clamping stops is patch between mandrelling head and stop. Lower stop is made in the form of cone with slots in which patch stopping plates are located on hinges with spring-loaded lugs. In operating state, plates assume position perpendicular to patch generating lines and coming in contact by its one end with patch lower end and by its other end with steps of slots of conical stop. Building up of excessive pressure in system results in cycle of forcing of mandrelling head through patch. Cycles are repeated until mandrelling head comes out of patch. EFFECT: higher reliability, servicing efficiency factor and serviceability of device. 4 dwg