SU1620588A1 - Bit for rotary drilling - Google Patents

Abstract

The invention relates to the mining industry and allows to increase the efficiency of the bit (D) for rotary drilling by increasing the drilling rate and reducing dust generation. The forward feather (P) 3 and lagging P 4, more distant from D axis, are located in the housing 1 D, forming a cutting 7. The inner side face 8 P 4 is provided with a ledge 9 with a core destructive insert (KB) 10 with a positive a rake angle, a cutting edge 11 lying in the main diametral plane, and an outer 12 and inner 13 side edges parallel to the D axis. The outer side edge 14 of the P 3 and the inner side edge of 8 P 4 are parallel to the axis D. The inner side face 15 P 3 and outer side face 16 П 4 parallel between and is inclined toward the axis L at an angle in the direction of reducing the width of feathers from their tops to the substrate. The ratio of the distance (lg) from the axis D of the inner side face 13 KB 10 to the similar distance (Lp) of the intersection line 17 of the working end 18 P 3 with its inner side face 15 and the ratio of the height (hg) KB 10 from the bottom of the cut 7 to the same The height (Hp) P 3 is between 0.3 and 0.5. In the process of drilling, P 3 cuts an annular gap in the array. Following it, P 4 expands the well (hole) to the required diameter, and KB 10 reduces the core to a size that ensures its destruction by a large cleaver. 3 il. S (L OE 1C

Description

The invention relates to the mining industry, namely to bits for rotary drilling.

The aim of the invention is to increase the efficiency of the bit by increasing the drilling rate and reducing dust generation.

FIG. 1 shows a chisel, front view; in fig. 2 - the same, top view; in fig. 3 - the same, side view.

The bit includes a body 1 with a shank 2 and two uneven and distant from the longitudinal axis of the bit 3 and 4, equipped with carbide inserts 5 and 6, respectively. Pen 3 is advanced and is located closer to the bit axis, and feather 4 is lagging behind and more distant from the bit axis. Cutting 7 is formed between feathers 3 and 4. The inner side face 8 of the lagging feather 4 is provided with a step 9 on which a core-fracture insert 10 is placed, having a positive rake angle (a), a cutting edge 11 lying in the main diameter plane and an outer 12 and inner 13 side faces parallel to the axis of the bit. The outer lateral face 14 of the advanced 3 and the inner lateral face 8 of the lagging 4 feathers are parallel to the axis of the bit, and the inner lateral edge 15 of the forward 3 and the outer lateral edge 16 of the lagging 4 feathers are parallel to each other and inclined to the axis of the bit at an angle (p) equal to 2- 3 °, in the direction of decreasing the width of the feathers from their tips to the base. The ratio of the distance (/) from the bit axis of the inner side face 13 of the core-destructive insert 10 to the similar distance (Lft) of the intersection line 17 of the working end 18 of the forward feather 3 with its inner side face 15 and the ratio (/ ed) of the core-destructive insert 10 from the bottom of the slit 7 to the similar height (H) of the forward feather 3 is from 0.3 to 0.5.

Chisel works as follows.

During the drilling process, the axial load and torque are transmitted to the bit, under the action of which the advanced feather shaft 3 nearest to the bit axis cuts through the annular gap in the mountain massif, and the feather 4 next to it lagging far away from the bit axis forms a hole (hole), lightweight mode due to the additional surface of the exposure, created by the first feather. The core formed in this case is reduced by a core-destructive insert to a size that ensures the destruction of the core by a large chip. Perform outer lateral

faces 14 of the forward 3 and the inner side face 8 of the lagging 4 feathers are parallel to the axis of the bit, and the inner side face 15 of the forward 3 and the outer side

the edges 16 of the lagging 4 feathers inclined to the axis of the bit and parallel to each other create free gaps between the above-mentioned edges of the bit feathers and the borehole walls and the lateral surface of the core, thereby preventing the crushing and abrasion of the broken rock falling between the first bits and the cylindrical surfaces wells (hole) and core.

Due to the fact that the feather and the core5 of the breaking bit insert destroy the array along different cutting lines with additional outcrop surfaces and guaranteed gaps between the bit feathers and the hole walls (hole) and the core, the drilling rate and

0 decreases dust output. All this increases the efficiency of the bit.

Claims (1)

Invention Formula 5 Chisel for rotary drilling, comprising a housing with a tail, two forming rassechka of different height and feather bits of different lengths from the longitudinal axis, of which the more distant feather is made lagging behind, characterized by 0 in order to increase the efficiency of the bit by increasing the drilling rate and reducing dust generation, it is equipped with a core-destructive insert placed on a ledge made on the inner side face of the lagging feather, 5 of this core destructive insert has a positive rake angle and a cutting edge lying in the main diametrical plane and side faces parallel to the axis of the bit, with the outer side edge of the forward and inner side of the lagging feathers parallel to the axis of the bit, and the inner side edge of the forward and outer side edge the lagging feathers are parallel to each other and inclined to the bit axis at an angle of 2-3 ° in the direction of reducing the width of the feathers from their tops to the base, with a ratio of the distance from the bit axis to the inside nney side face kernorazrushayuschey insert similar to the distance the line of intersection of the working end of the pen with his best 0 the inner side face and the ratio of the height of the core-forming insert from the bottom of the slit to the similar height of the forward feather is from 0.3 to 0.5. 0 G8 eleven GO eleven FIG. 2 Fig.Z