MACHINE FOR PIPE CUTTING Russian patent published in 1997 - IPC

FIELD: mining industry, oil and gas industry. SUBSTANCE: invention deals with pipe cutting by lowering of machine into interpipe clearance of string of pipes to be out. Fluid from pipe conduit goes to central conduit, then goes into ring space through radial conduit, comes through conduits from body into interpipe clearance and rises through it to well-head. Pressure of fluid caused by velocity head acts on piston since summary passage of radial conduits is less than passage of pipe conduit. Under action of force caused by this velocity head piston moves downwards and presses on cutters with its end forcing them turn about axes. Cutters come out of grooves with turn. Cutters acts on pusher which moves together with stepped shank in axial hole. Moving pusher compresses spring which rests against thrust plate with other end. Cutting process starts from moment of touching of internal surface of cut casing with cutters. EFFECT: improved cutting efficiency. 2 dwg