METHOD AND DEVICE FOR STRENGTHENING BOTTOM-HOLE ZONE OF GAS WELLS Russian patent published in 1997 - IPC

FIELD: mining industry. SUBSTANCE: this refers to underground overhaul of gas wells with their bottom-hole zone being made of loose-cemented reservoirs. Ensured is efficiency of gas well bottom-hole zone control process, simplified realization of process proper. Use of sophisticated ground surface machine is also excluded. According to method, sand plug is crushed in well bore. Then well bore is widened in buttonhole zone. Well is flushed, drilling tool is raised and tubing string is lowered into well bore. String is provided with packer and other underground equipment. Connected to lower end of tubing string is pipe union with radial passages which accommodate nozzles. Valves are installed above and below pipe unions. Upper level of nozzles is located at top of down-hole zone. Well mouth is hermetically sealed. Well is subjected to completion and air-blown for cleaning. Then this operation is stopped and static intake pressure is measured. Dropped into tubing string is ball-type shut-off member which is seated in valve. After that, pumped into well is portion of liquid binding compound. Separating plug is pressed down into tubing string. After shearing of valve and location of ball-type shut-off member in valve, down-hole zone is treated with binding compound through nozzles. Gas found in tubing string is displaced into hole clearance of tubing string with the help of separating plug. After resetting of well-head pressure in hole clearance of tubing string to required pressure, well is started for operation at reduced output. Upon hardening of binding compound, well operation is stopped, pressing is renewed and using packer, ball-type shut-off member and separating plug are pressed out to bottom hole. Well is recompleted, blown out and started for operation along tubing string at design output. EFFECT: high efficiency. 7 cl, 2 dwg