HYDROMECHANICAL WELL PERFORATOR Russian patent published in 2008 - IPC E21B43/112 

FIELD: mining.

SUBSTANCE: invention concerns the field of well drilling and development. The perforator includes a compound case with upper and lower hydraulic cylinders, an adapter with bypass valve, pullout cutting tool in the form of a crush roll with calibration grooves. A hollow rod is placed in the two hydraulic cylinders sealed from each other. The hollow rod is linked to a spring-loaded piston of the upper hydraulic cylinder and to the piston follower of the lower hydraulic cylinder. The bypass valve is a spring-loaded two-diametre hollow piston with cavity. The cavity is located between the piston diametre sections and forms a hydraulic cavity together with internal surface of the adapter. The hydraulic cavity enters hole clearance. Calibration grooves are made at the side surface of the crush roll lead-in at given angles. The spring-loaded piston of the upper hydraulic cylinder is mounted on a hollow rod with possibility of reciprocal movement. The upper hydraulic cylinder is equipped with a stop collar to limit the piston's movement against the hydraulic cylinder.

EFFECT: improved reliability and range of technical application of perforator.

1 dwg