METHOD AND DEVICE FOR INITIATING INFLOW FROM STRATUM Russian patent published in 1996 - IPC

FIELD: arrangement of holes. SUBSTANCE: for smooth starting of hole operation and ensuring multiple creation of stratum depression, circulation valve is installed above packer during lowering pump and compressor tubing. Valve is positioned at depth sufficient for pushing down of gaseous agent at maximum pressure produced by compressor. Overflow unit is installed and it is hydraulically connected with tube space. Technological fluid is added into tube string to level below circulation valve, then working agent is pumped at maximum possible pressure, and before opening of valve unit tube space is closed and tube pressure is periodically released up to complete outflow of gaseous agent. Device for initiating inflow from stratum is provided with additional pipe fitting connected with overflow unit and made in the form of pipe section with valves at its two sides and pressure gauge. Circulation valve represents sleeve with end stop and side bores closed in extreme upper position by shear bush axially movable up to sleeve end stop. Closing member of valve unit is formed as hollow shear bolt. Under-piston space of cylinder is hydraulically connected with space of perforated end piece. Piston diameter is less than inner diameter of perforated end piece which is provided with circular stop in its lower part for piston sealing. Mass of pin exceeds friction force which keeps piston in cylinder. EFFECT: high efficiency. 2 cl, 8 dwg