Self-cleaning and anti-seize tubular pump for coal-bed gas well

Abstract

The invention relates to a self-cleaning and anti-seize tubular pump for a coal-bed gas well. The self-cleaning and anti-seize tubular pump comprises a coupling, a pump cylinder, a self-rotating type combination plunger, a deposition-preventing fixed valve and a self-cleaning type liquid sucking opening, wherein the upper end of the coupling is connected with an oil pipe, the lower end of the coupling is connected with the top end of the pump cylinder, the self-rotating type combination plunger is located in the pump cylinder, the upper end of the deposition-preventing fixed valve is connected to the bottom end of the pump cylinder, and the lower end of the deposition-preventing fixed valve is connected to the top end of the self-cleaning type liquid sucking opening; and the self-rotating type combination plunger adopts a rubber piston structure and an automatic rotating mechanism. According to the self-cleaning and anti-seize tubular pump, the designed self-cleaning type liquid sucking opening carries out spiral separation on sucked liquid so as to prevent large-particle coal powder mud from entering the pump, and the separated particles can be rapidly discharged; the deposition-preventing fixed valve is adopted to change the flowing direction of liquid, carry out spiral rapid scouring on coal powder mud depositing at the bottom of the pump cylinder, and reduce the deposition of the coal powder mud in the pump cylinder; and as the rubber piston structure and the automatic rotating mechanism are adopted, the self-rotating type plunger consisting of a flexible seal and a hard seal is formed, and plunger seize failures caused by coal powder mud are reduced.

Description

technical field [0001] The invention belongs to the technical field of coalbed gas exploitation, and in particular relates to a self-cleaning and anti-jamming pump for coalbed gas wells. Background technique [0002] Coalbed methane drainage is to discharge water from the coalbed methane well through pumping, so that the pressure of the coal reservoir is reduced below the critical desorption pressure of the coalbed methane, so that the adsorbed methane is desorbed into a large amount of free methane and transported to the wellhead. [0003] Tubular pumps are one of the most widely used extraction tools for coalbed methane. However, due to the fact that a large amount of coal powder, mud sand and other abrasive particles are likely to be produced in the process of coalbed methane extraction, ordinary tubular pumps cannot be well adapted to coalbed methane wells. Particles such as coal powder, mud and sand enter the pump, which will easily cause blockage of the pump suction po...

AI Technical Summary

Problems solved by technology

[0003] Tubular pumps are one of the most widely used extraction tools for coalbed methane. However, due to the fact that a large amount of coal powder, mud sand and other abrasive particles are likely to be produced in the process of coalbed methane extraction, ordinary tubular pumps cannot be well adapted to coalbed methane wells. Particles such as coal powder, mud and sand enter the pump, which will easily cause blockage of the pump suction port, lax valve closure, plunger wear and leakage, plunger stuck and other faults, thus greatly shortening the pump inspection cycle of coalbed methane wells, increasing development costs, frequent The pump inspection and workover operation damaged the coal reservoir and seriously affected the continuity of coalbed methane drainage

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