Down-hole water drainage and gas production tool

Abstract

The invention discloses a down-hole tool used for water drainage and gas production of a natural gas well in the field of oil drilling and production. According to the technical scheme of the down-hole water drainage and gas production tool, the tool is composed of a transition connector, a packer module, an overflow valve module, a reversing valve module, a pilot valve module, an actuating module, a second pump module, a check valve short section, a first pump module, a check valve short section, a bottom end and a main outer cylinder. According to the tool, extra energy supplying is not needed, and only natural gas generated by the natural gas well self serves as a power resource. Gas enters from a gas inlet in the tool, is pressurized by multi-stage air cylinders and drives a reciprocation pump mechanism to work, and therefore accumulated liquid in the well is conveyed to the ground through an oil-line pump. The natural gas enters an oil sleeve annular space through a gas outlet in the tool and flows to a ground production pipeline. The down-hole water drainage and gas production tool can be applied to water drainage and gas production operation of vertical wells, deviated wells and horizontal wells, has the advantages of being simple in construction operation, low in operation cost and free of pollution for a stratum and is suitable for water drainage and gas production operation of low-pressure and low-gas-production wells.

Description

technical field [0001] The invention relates to a downhole tool used for drainage and gas recovery of natural gas wells, which belongs to the field of petroleum drilling and production. Background technique [0002] When the low-porosity and low-permeability weakly elastic water drive gas field enters the mid-to-late development stage, the bottom water will rise and the edge water will advance due to the drop in formation pressure; Production causes serious damage, mainly manifested in: formation water accumulates at the bottom of the well, increasing the back pressure at the bottom of the well, thereby reducing gas production, and in severe cases, causing gas wells to be flooded and shut down; Causes great pollution and damage; therefore, fast and effective liquid drainage is the key to ensure the normal production of gas wells; domestic and foreign research on natural gas well drainage gas recovery technology has a history of many years and a series of drainage gas recover...

AI Technical Summary

Problems solved by technology

[0003] At present, for low pressure and low gas production wells, the mechanical pumping drainage gas recovery process can be used, but this process is easily limited by the well type, and cannot be used for drainage and gas recovery operations in highly inclined wells and horizontal wells; at the same time, mechanical pumping drainage The investment cost and maintenance cost required by the gas production process cannot meet the development needs of low-yield gas wells; therefore, a drainage gas recovery tool specially suitable for low-pressure, low-yield gas wells is needed to reduce investment while meeting the well type adaptability requirements as much as possible. Cost and operating costs, thereby improving the economics of low-pressure, low-production gas well development

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