SU1665014A1 - Roller cutter for soft rock - Google Patents

Abstract

The invention relates to the mining industry and is intended for a roller cutting tool of a roller cone type. The roller cutter has a body in which the gear rims are located, at least one of which has a wedge-shaped tooth with a sharpened angle and with a constant blunting of the apex. Interdental depressions have an inclined bottom. The tooth is made with an angle at the base, the top of which is located on the periphery of the roller cutter, and the faces intersect with the edges of the cusp at the height H, which is determined by the mathematical angle. In this case, the interdental cavity in the cross section is made in the form of a trapezium, the smaller base of which is located on the side of its entrance. The upper part of the tooth, having a greater angle of sharpening, when embedded in the face, performs the main work on the deformation of the rock, the lower part of the tooth, made with a smaller angle, takes less part in the deformation of the rock. Reducing the angle of blunting leads to a decrease in friction forces acting on these surfaces. All this provides a reduction in the adhesion of rock to the side surfaces, as well as a reduction in the penetration force. 3 il.

Description

The invention relates to the mining industry, namely to a rock-breaking drilling tool, of a roller conic type, intended to destroy soft rocks.

The purpose of the invention is to increase the drilling efficiency by reducing the penetration force and improving the removal of sludge.

Figure 1 shows a roller cutter for drilling soft rocks; figure 2 is a view of And figure 1; on fig.Z - section bb in figure 2.

The roller cutter includes a housing 1 with several, for example three, crowns of 2-4 teeth. The lateral surfaces of the teeths of the crowns 2 and 3 are formed by two planes 5 and 6 intersecting at the height of the tooth h.

The soles 5 at the base of the tooth form an angle α3, which is smaller than the angle of the apochite a, formed by the planes b.

Since the lateral surfaces at the base of the tooth are oriented relative to the axis of the cone, at an angle y, the teeth at the base have a variable cross section, decreasing in the direction of the rinsing direction (Fig. 3). The bottom of the 7th cavity is sloped. The teeth of ranks 2 and 3 are made with permanent blunting.

The value of h is determined from the expression

ABOUT

about eaten about

one

tga / 2

tgg / 2 l tg / ff / 2 H)

where a is the angle of sharpening;

 base angle;

H is the height of the tooth.

The work of the roller cutter is as follows.

During the drilling process, the roller cutter rolls over the face and a load is applied to it, which is transmitted through the support to the teeth of rows 2-4. Under the action of the applied force, the latter are introduced into the rock slab, destroying it. The deformation of the breed of the teeth of the rows 2 and 3 is carried out by the upper part of the tooth, which has a large angle of sharpening.

The upper part, having a large sharpening angle, when inserted into the face, performs the main work on rock deformation, while the lower part of the tooth, made with a smaller angle, is less involved in rock deformation. In addition, a decrease in the blunting angle also leads to a decrease in the frictional forces acting on these surfaces. All this provides a reduction in sticking of the rocks to the side surfaces, as well as a decrease in the penetration force.

The increase in the volume of the interdental cavity by making the tooth in the lower part thinner with its width exceeding 3-5 times the thickness of the tooth allows

reduce the degree of compaction of the rock, which also reduces sticking.

Claims (1)

Claims of the invention Sharoshka for drilling soft rocks, comprising a housing, teeth that are located on the housing, at least on one of which the teeth are wedge-shaped with a sharpened angle and with a constant blunting of the apex, and the interdental depressions with a sloping bottom, characterized by the fact that. in order to increase drilling efficiency by reducing the penetration force and improving the removal of cuttings, the teeth are made with an angle at the base, the apex of which is located on the periphery of the cone, and the faces intersect with the edges of the sharpening angle at a height h determined from the expression tgcc / 2 ЩЩ one - / jlv (n) where a is the angle of sharpening;  base angle; H is the height of the tooth moreover, the intereubtsovaya depression in the cross section is made in the form of a trapezium, the smaller base of which is located on the side of its entrance. Editor N. Yatsola Phys. 2, Compiled by A. Skalunov4 Uc, 3 Tehred M.MorgentalKorrektor S.Cherni 6