DEVICE FOR CUTTING PIPES IN DEPTH Russian patent published in 1998 - IPC

FIELD: bore-hole drilling machinery and equipment. SUBSTANCE: this can be used for cutting pipes deep in bore-holes filled with water. Device for cutting pipes in depth has cylindrical body with nozzle. Cylindrical body has lengthened part which accommodates longitudinally movable differential piston which divides cylindrical body into above-piston space and two under-piston spaces. One of these two spaces is hydraulic and other one is made hermetic. Above-piston space communicates with ambient medium. Differential piston is fixed relative to cylindrical body by locking unit. Hydraulic above-piston space is connected with nozzle. Locking unit is brought in operation at required depth according to command signal. In this case, working pressure in hydraulic space becomes several times higher than ambient medium pressure. Due to excess pressure, stopper is broken and in result working liquid under high pressure is discharged through slot-type nozzle with subsequent cutting of pipe. Application of aforesaid embodiment of device improves safety of operation, cuts operation cost and greatly increases efficiency and quality of cutting due to fact that used as energy source is hydrostatic pressure of liquid found in bore-hole. EFFECT: higher efficiency. 1 dwg