METHOD FOR LIFTING FLUID FROM WELL AND DEVICE FOR ITS EMBODIMENT Russian patent published in 1996 - IPC

FIELD: oil and gas producing industry; applicable in recovery of fluid from oil, gas and gas-condensate wells. SUBSTANCE: to reduce power consumption for lifting fluid from well, due to use of pressure of formation gas or injected gas, circular gap is left between the lowered unit and walls of tubing, and lifting is performed at the rate determined by the relation where V is speed of lifting of lowered unit, m/s; F is flow area of tubing, sq.m; Qf is fluid production rate, cu.m/s; Qg is gas production rate, cu. m/s; Qdf is dynamic characteristic of the device, cu. m/s. During running into well of lowered unit gas flow from the well is limited of fully cutoff. After beginning of over-flow of fluid through wellhead, the speed of lowered unit is reduced, and after overflow through wellhead of 10% of the height of column of the well, lowering is stopped. Lowering of lowered unit in the next cycle is continued up to the end of fluid overflow through wellhead in the previous cycle. Device for fluid lifting from well has lowered unit which is located in the string of tubing with circular gap to transmit gas pressure to fluid in lifting the device from well, and is provided with centralizer. Winch lifting speed is regulated. Area of circular gap amounts to 25% of the tubing flow area. Lowered unit is a rod with axial channel. Lower part of the rod is embraced by accumulator in form of cylindrical sleeve with funnel. Check valve is made in form of circular limiter protruding on the rod surface. Reverse attachment is located above circular limiter for motion along rod. Rod axial channel has side passages to inside of accumulator, to external surface of limiter and, in the upper part, to hollow of tubing. External surface of limiter and surface of reverse attachment are conical in shape and engageable. Limiter surface has annular recess communicated by means of side passages with rod axial channel. Reverse attachment has through channels along its axis, or inclined to it, which begins from opposite annular recess on limiter surface. Conical surface of reverse attachment has mating annular recess of the limiter. Funnel of accumulator is connected with rod of the lowered unit by means of connectors. Accumulator is connected to the lower end of rod of the lowered unit. Lowered unit has grid or tubular body with longitudinal slots. Check valve is made in form of bushing and float accommodated inside the body, with body at the level of bushing embraced with external solid ring. Float freely rests on bushing. Body accommodates spring limiter which is located above bushing, and float is suspended from external limiter inside the bushing. Float and bushing hole are of conical shape. Float has through axial hole. Passing along axis of body is guide rod or wire rope. Diameter of tubing reduces step by step in depth. Installed over the external solid ring are additional adjusting rings for sliding, whose number corresponds to the number of steps of tubing diameter, and thickness of each next ring equals the value of step transition of tubing. EFFECT: higher efficiency. 21 cl, 9 dwg