Borehole cleaning tool for horizontal-section gas drilling

Abstract

The invention discloses a borehole cleaning tool for horizontal-section gas drilling. The borehole cleaning tool consists of a main body, spiral flow channels, alloy teeth and joints, wherein two ends of the main body are the joints; the spiral flow channels are located in the main body; the spiral flow channels comprise a front spiral flow channel which takes up one third of the length of the spiral flow channel and a rear spiral flow channel which takes up two thirds of the length of the spiral flow channel; unequal-diameter alloy teeth are respectively embedded into the strengthening bars of the front spiral flow channel and the rear spiral flow channel; an inclined U-shaped groove of which the cross section is 2cm to 4cm deep is formed in the rear spiral flow channel. According to the borehole cleaning tool, as the spiral flow channels which are of a composite structure respectively are adopted, the flow speed of gas is increased, and the orbiting flow of an annular air body is enhanced; the windward sides of the spiral flow channels are respectively provided with the inclined U-shaped groove, so that a great deal of rock waste is annularly hoisted in the sky; as the different-size alloy teeth are respectively embedded into the strengthening bars of the spiral flow channels, the grinding of rock waste in rotation is enhanced; the borehole cleaning tool is reliable in principle, rational in structure, and applicable for a horizontal borehole drilling technology under the working conditions of gas drilling and fluid drilling, thereby having a broad market prospect.

Description

technical field [0001] The invention relates to a tool for purifying the borehole of a horizontal well during the drilling process in the field of petroleum engineering. Background technique [0002] When drilling wells with large inclination angles such as highly deviated wells, horizontal wells, and extended-reach wells, it is easy to have difficulties in cuttings migration downhole, and cuttings will be retained and accumulated in the lower side of the wellbore, forming a certain length Debris bed. The formation of the cuttings bed increases the drilling torque, makes it difficult to apply the drilling pressure and even causes the danger of the drill sticking, which leads to the inability of the drilling to proceed smoothly, resulting in huge economic losses. [0003] In order to solve the formation of the cuttings bed, there are currently some tools for removing the cuttings bed, but their functions are not very satisfactory: the vortex cleaning drill pipe disclosed in ...

AI Technical Summary

Problems solved by technology

The special tools or new structure centralizers involved have the function of cleaning the cuttings bed to a certain extent, but they cannot well meet the needs of gas drilling horizontal wells to clean the cuttings bed, because during the process of gas drilling horizontal wells, cuttings The buoyancy and impact force of the fluid on the particles is far less than that of conventional mud drilling, and the kinetic energy of gas per unit volume is also less than that of drilling fluid

[0005] It can be seen that there are currently few tools that can change the flow field, break the rock again, and lift the cuttings to the clean cuttings bed in the annulus

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