Coal mine underground gas extracting hole-drilling double-channel direct-reversed circulation water vapor braid

Abstract

The invention discloses a coal mine underground gas extracting hole-drilling double-channel direct-reversed circulation water vapor braid. The coal mine underground gas extracting hole-drilling double-channel direct-reversed circulation water vapor braid comprises an outer tube hollow shaft (1), an inner tube assembly (3), a guiding sealing box (11) and a gang drilling cuttings sealing box (17). The inner tube assembly (3) is plugged in the outer tube hollow shaft (1) to form a rotatable bi-layer structure, the outer tube hollow shaft (1), the guiding sealing box (11) and the gang drilling cuttings sealing box (17) are connected together through screw threads, and a quick coupling (10) is arranged on the guiding sealing box (11). According to the coal mine underground gas extracting hole-drilling double-channel direct-reversed circulation water vapor braid, the volume is small, the weight is light, and the rotation is flexible; the guiding effect is good, the bearing operation is smooth and steady, and the high-speed revolution can be met; and the sealing performance is good, the circulation is leak-tight, the working performance is stable, and the assemble and un-assemble is lightweight and labor-saving.

Description

technical field [0001] The invention relates to a dual-channel positive and negative circulation water-gas braid in an underground gas drainage borehole of a coal mine, which is suitable for deep-hole drilling in an underground soft and hard composite coal seam gas drainage borehole. Background technique [0002] The double-channel forward and reverse circulation water-air braid in the underground gas drainage drilling of coal mine is used to connect the high-pressure rubber hose and the support slag discharge pipe. It is the supporting equipment for positive and negative circulation drilling. At present, the gas drainage drilling technology of soft and hard composite coal seams in coal mines adopts positive circulation drilling, and the water-air braid used is a single channel that can only send the flushing medium into the hole. Drain from the wall annulus. Due to the poor stability of soft and hard composite coal, the gas content is high. As the drilling depth increase...

AI Technical Summary

Problems solved by technology

[0004] Therefore, those skilled in the art are committed to developing a dual-channel circulating water-air braid for drilling underground gas drainage in coal mines, which can effectively solve the problem that the reverse circulation water-air braid in geological drilling is heavy, and its diameter, length, and structure are not suitable for coal mine underground drilling. , reduce the probability of accidents such as hole wall collapse, hole blocking, stringing holes, and drill pinching in positive circulation drilling, and greatly improve the efficiency of underground gas drainage in coal mines

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