HYDROMECHANICAL WELL PERFORATOR Russian patent published in 2002 - IPC

FIELD: drilling and operation of wells, particularly, devices for making perforation slots in casing string, cement stone and rocks. SUBSTANCE: hydromechanical well perforator has body, extensible cutting tool in form of rolling disk, jet nozzle and wedge recess with removable plates arranged at angle to device axis. Axle of rolling disk is stepped, with small diameter at ends and located in recesses parallel to wedge recess. Device has hollow rod-filter located in two hydraulic cylinders installed hermetically relative to each other. Lower hydraulic cylinder has spring-loaded piston-pusher having central and side hydraulic channels and connected with axle of rolling disk by means of two shaped plates. They come in contact with removable plates of wedge recess. Wedge recess is removable and installed on device body for sliding over casing string during operation of rolling disk. Ends of axle of rolling disk are located in guide recesses of side plates. They embrace wedge recess, shaped plates and rolling disk from both sides. EFFECT: provided convenient servicing, and simple in design and reliable in operation device with wide range of application. 3 cl, 2 dwg