The central through hole can be opened and closed high and low voltage switching device

Abstract

A central through-hole openable and closable hydraulic reaming device, comprising an outer pipe joint and a central through-hole opening and closing assembly located inside the outer pipe joint. The central through-hole opening and closing assembly includes a base, a movable ring, a spring, and a connecting rod , hinge cover and gland, the spring fits on the outer edge of the connecting rod, one end leans against the base, the other end leans against the movable ring, one end of the connecting rod is fixed to the base, and the other end is hinged to the hinge cover , the movable ring is provided with a cavity, the upper part of the cavity is covered with the hinge cover, and the lower part of the connecting rod passes through, and the gland can lean against the hinge cover when the hinge cover protrudes from the cavity. The hinge cover rotates inward to close the central through hole; thus, the present invention is simple in structure, easy to operate, and reusable, and solves the problem of using the existing hydraulic reaming technology while drilling for gas drainage in underground coal mines in broken soft coal seams. When drilling, the channel between the hole-making points is blocked after the drill is lifted, which results in the problem that the hole protection screen cannot be lowered to the drilling depth.

Description

technical field [0001] The invention relates to the technical field of underground drilling in coal mines, in particular to a central through-hole openable and closed high-low pressure switching device suitable for the drilling-type hydraulic reaming of underground holes in soft coal seams in coal mines and the construction of screen pipe protection hole drilling. device. Background technique [0002] In recent years, with the development and popularization of hydraulic drilling, expansion technology and supporting equipment, many coal mines have used this technology to improve drainage efficiency, reduce the time for drainage to reach the standard, accelerate the speed of coal roadway excavation, and effectively alleviate the problem of "drainage". ", Digging, Mining" takes over the tense situation. [0003] At present, in the hydraulic reaming device used in the market for the hydraulic reaming process, the central through hole is blocked by the piston body, and its high ...

AI Technical Summary

Problems solved by technology

[0010] The purpose of the present invention is to provide a high and low pressure switching device with a central through hole that can be opened and closed, which has a simple structure, is easy to operate, and can be used repeatedly, so as to solve the problem of the existing drilling-while-drilling hydraulic reaming technology in the construction of holes in broken and soft coal seams in underground coal mines. When the gas drainage is drilled, the channel between the hole-making points is blocked after the drill is lifted, so the hole protection screen cannot be lowered to the depth of the drill hole

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