Pumping device for PE (polyethylene) screen pipe well completion of coal-bed gas horizontal well and pumping method

Abstract

The invention discloses a pumping device for PE (polyethylene) screen pipe well completion of a coal-bed gas horizontal well and a pumping method, and belongs to the technical field of coal-bed gas. The upper end of a body is a pressure bearing surface; a guide hole is formed in the middle part of the pressure bearing surface; a threaded connection part is arranged in the guide hole; the lower end of the body is a hemisphere guide head; a drainage hole is connected with the guide hole; the other end of the drainage hole is arranged on the middle part of the hemisphere guide head; a part, which is connected with the guide hole, of the drainage hole is a slope. The pumping device has the effects that enough impact force can be generated, and a screen pipe is successfully driven to move downwards to reach a target layer; a proper clearance is reserved between the outer rim of the pumping device and a drill rod, so that the phenomenon that the moving direction of the screen pipe is deflected or the screen pipe is blocked due to a fact that impurity particles in drilling fluid are clamped in the clearance is effectively avoided; in the process of driving the screen pipe to move downwards, the screen pipe can be successfully driven to pass through a joint of the drill rod and a bent section of a borehole, so that a clamping accident is avoided.

Description

technical field [0001] The invention relates to a pumping device and a pumping method for PE screen tube completion of a coalbed gas horizontal well, belonging to the technical field of coalbed gas. Background technique [0002] Coalbed methane is a gas that exists in coal rocks, and its composition is mainly methane, commonly known as gas. Coalbed methane is an important unconventional resource. my country is rich in coalbed methane resources, with proven geological reserves of about 36.8 trillion cubic meters. [0003] Most of the middle and high-rank coal seams in my country have the characteristics of low pressure and low permeability, so U-shaped horizontal wells or horizontal multi-branch wells, which can greatly increase the drainage area, should be used for CBM development. The brittleness of coal rock is strong, and it is easy to produce a large amount of pulverized coal and coal lumps to fall during the mining process. In severe cases, the flow channel will be blo...

AI Technical Summary

Problems solved by technology

The brittleness of coal rock is strong, and it is easy to produce a large amount of pulverized coal and coal lumps to fall during the mining process. In severe cases, the flow channel will be blocked and the production of coalbed methane wells will be reduced.

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