Plunger lifting drainage gas recovery downhole device for horizontal shale gas well and working method

Abstract

The invention discloses a plunger lifting drainage gas recovery downhole device for a horizontal shale gas well and a working method. The plunger lifting drainage gas recovery downhole device mainly comprises a sleeve, an oil pipe, a plunger and a limiting short circuit. After the well is shut in, the plunger descends in a gas column in an accelerated manner through dead weight, then impacts the liquid level at a high speed, instantaneously generates large resistance to suddenly reduce the speed, then descends in a liquid column at a low speed, and finally stops at an inclined well section along with continuous increase of a hole deviation angle; and if the liquid level position is low, the plunger can descend to the nearly horizontal section of the oil pipe, but due to the fact that the inner diameter of the limiting short circuit is smaller than the outer diameter of the plunger, the plunger cannot fall out of the oil pipe. The downhole device and the working method have the advantages that the problems that an existing locking device is difficult to descend into the inclined well section, high in construction risk and the like are solved, the technological process is simplified, the operation cost is reduced, and the plunger lifting drainage efficiency of the horizontal well is improved.

Description

Technical field[0001]The present invention relates to the field of gas-hiding drainage, and more particularly to a row of rock gas horizontal well plungering and drainage water supply and gas downhole devices and working methods.Background technique[0002]The rock gas is used in a length of 1000 ~ 4000m, and the large hydraulic segment fracturing is mining. The fracture liquid is used to have a large amount of fracture liquid (all-well section 15000 ~ 48000m)3), While the daily gas volume is decremented, the amount of gas is small after entering the stable period of time, and the amount of water carries is small. Due to the long section and the horizontal segment, the liquid phase slip is severe, the fluid is large, and the gas output is severe. Therefore, the wellbore fluid must be discharged to ensure normal production.[0003]Pluna lifting is one of the commonly used drainage and gas supply processes of the fluid gas well. Traditional plunger lifting system downhole devices include ...

AI Technical Summary

Problems solved by technology

For some shale gas wells with small water production, the depth of the liquid level is lower than the inclination position of the well. At this time, because there is no liquid in the upper part of the plunger, it will automatically fail, and the wellbore fluid cannot be effectively discharged.

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