Rotary drilled hole sealing device for air drilling

Abstract

A rotary drilled hole sealing device for air drilling can be used for the technical fields such as air drilling, mine blasting hole construction and geological exploration. The device comprises sealing semicircular sliding blocks, a sliding block base, clamping springs, spring pull rods, a connecting core pipe, fixing bolts, bearing glands, bearing blocks, a hole connecting pipe, bearings, a sealing packing, rubber sealing sheets and spring baffles. A rotating drill pipe is clamped by the sealing semicircular sliding blocks under the action of the clamping springs, the drill pipe rotates to drive the sealing semicircular sliding blocks, then the sliding block base, the connecting core pipe and the bearings are driven to rotate together, and accordingly rotation of the sealing device is achieved. Rotary sealing avoids abrasion of a sealing material is avoided, so that the sealing effect is better. The clamping springs provide clamping force and can adjust the clamping force in time according to resistance, and the resistance of the drill pipe is reduced to the largest extent. The sealing semicircular sliding blocks in different specifications can be replaced to meet requirements fordrill pipes in different specifications.

Description

technical field [0001] The invention relates to a drilling tool, which can be used in the technical fields of air drilling, mine blast hole construction, geological exploration and the like. Background technique [0002] Air drilling is an underbalanced drilling technology in which compressed air is used not only as a circulating medium but also as energy for breaking rocks. Since the birth of air drilling technology, it has been highly concerned by domestic and foreign drilling circles. Because of its high drilling efficiency, strong formation adaptability, good cleaning and cooling conditions at the bottom of the well, effectively avoiding the occurrence of complex situations such as lost circulation, and adapting to drought conditions It has been widely used in hydrology and water well drilling, oil and gas drilling, geothermal drilling, mine exploration and other fields. In air drilling, during the circulation process in the hole, the air carries the cuttings broken by ...

AI Technical Summary

Problems solved by technology

In the process of conventional positive circulation air drilling or reverse circulation drilling, there is air going back up from the borehole at a very high speed (speed greater than 15m / s), if there is no orifice sealing device at the orifice , the air carrying cuttings is ejected from the orifice, and the rock samples broken by the drill bit cannot be completely obtained, and the composition of the stratum or minerals cannot be truly reflected, and it is difficult to meet the requirements of geological exploration

[0004] The conventional sealing device is fixed, and the sealing device does not rotate with the drill pipe. Rubber or other sealing materials are filled between the device and the drill pipe. Since the filling material cannot be closely attached to the drill pipe, there is a gap between it and the drill pipe. Under the conditions of blowing flow and rotary wear, the gap is also increasing, which will soon lead to the failure of the seal, and a large amount of rock dust will be generated at the orifice, which will seriously affect the normal drilling work.

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