Special anti-impact drill bit

Abstract

The invention relates to a special anti-impact drill bit. The special anti-impact drill bit comprises a drill body connected with a bit holder at the tail. A cutting edge with combination of curve distribution and a trapezoidal structure is arranged at the front portion of the drill body and is a cylindrical coated alloy welded to a three-wing structure. A cutting part of the drill body is in a curve shape; and the shape of a first outer arc-shaped section is determined according to the following formula (1), the formula of the shape from a first endpoint a to a second endpoint b is shown (please see the specifications for the formula), L1 represents the arc length of the first outer arc-shaped section, R represents the radius of the drill bit, and alpha represents the central angle from the first endpoint a to the second endpoint b. According to the special anti-impact drill bit, the front portion of the drill body is arranged in a trapezoid and curve type combined mode, the combiningstrength of the first outer arc-shaped section and the drill body serves as a benchmark parameter, when the drill bit works, a fixed stress intensity value is maintained, thus the blocking situationis avoided, and the well-drilling efficiency is further improved.

Description

technical field [0001] The invention relates to the technical field of drilling tool accessories for engineering drilling and coal seam prospecting, in particular to a special anti-shock drill bit. Background technique [0002] In many mines in my country, the coal seams have poor air permeability, soft coal quality, high gas content, and even dynamic phenomena or outburst dangers, making it extremely difficult to drill coal seam pre-drainage boreholes. When drilling with conventional water circulation, it is easy to collapse the hole, cause serious drill sticking, and the drilling depth cannot reach the design target, resulting in poor gas discharge and anti-rock impact effects, which cannot well meet the requirements of production and development, and affect the normal production of coal mines. conduct. [0003] The drill bit in the prior art requires a pile head with a certain height on the top of the pile due to the design requirement in construction, and the existing d...

AI Technical Summary

Problems solved by technology

When drilling with conventional water circulation, it is easy to collapse the hole, the drill is seriously stuck, and the drilling depth cannot reach the design target, resulting in poor gas discharge and anti-rock impact effects, which cannot well meet the requirements of production and development, and affect the normal production of coal mines. conduct

[0003] The drill bit in the prior art requires a pile head of a certain height in the upper part of the pile due to the design requirement in construction, and the existing drill bit is controlled by the experience of the construction personnel, resulting in the breakage of the drill bit during construction

[0004] At the same time, when the drill bit in the prior art is removing chips while working, due to the defect of the trapezoidal cutting edge structure, the strength of each section of chip removal is basically the same, causing chip removal to block

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