SU994670A1 - Rolling-cutter drill bit - Google Patents

Description

(54) DRILLING BALL CHIP

one

The invention relates to a rock-breaking tool, namely, roller cone bits.

A roller bit is known that contains a body and cones with a multi-conical surface, the apex of which is equally distant from the axis of the bit, while the teeth of the perpendicular rim are located on a conical surface whose apex is directed in the direction opposite to the apex of the cone 1.

The disadvantage of this bit is the low efficiency of the calibrating teeth on the peripheral rims.

Closest to the invention to the technical essence and the achieved result is a roller cone bit, containing sections with pins on which by means of bearings. mounted conical roller cutters with crowns, reinforced with carbide teeth with a working head in the form of a spherical segment with an inclined face 2.

However, this bit has a low mechanical speed of drilling.

The aim of the invention is to increase the mechanical rate of drilling.

This goal is achieved by the fact that in a roller cone bit, containing sections with trunnions, mounted by means of bearings are mounted conical roller cones with rims, reinforced with solid spherical teeth with a working head in the form of a spherical segment with an inclined face, the carbide teeth of the peripheral ring are oriented with a flat face at an angle of 40 -50 ° to the generatrix of the cone, while the angle of inclination ot of the flat face

 to the axis of the clove is determined by the formula

to-aC -J5 2J-1

where D is the diameter of the clove, mm;

H - the height of the working head, mm. FIG. 1 shows a chisel, a total 15 species; in fig. 2 - carbide bit, in two projections; in fig. 3 is a schematic of the location of the rods of the roller cones.

Claims (2)

The drill bit contains sections 1 welded to each other with trunnions 2, on which roller cones 3 are mounted with rims “willows reinforced with carbide teeth 4 with a working head in the form of a spherical segment with an inclined flat face. On the peripheral rims and the teeth are oriented with a flat face at an angle of 40-50 ° to forming a cone, which facilitates the cleaving of the rock at the junction of the borehole wall with the face towards the middle rims 8. The angle of inclination ot of the flat face to the axis of the tooth 4 S 2fr where D is the diameter of the notch, mm; H - the height of the working head, mm. Chisel works as follows. Rotation and axial force are transmitted through sections 1 to pins 2 and roller cones 3, which roll down the borehole and insert the heads of teeth 4 into the rock, which leads to its destruction. The working head with a sloping flat edge also has a smaller contact surface with the rock and destroys it with two working surfaces: spherical by crushing and flat by cleaving. In addition, at the points of contact of the working head edges (at the intersection of its spherical and flat parts), a stress concentration arises in the rock, which promotes the formation and development of cracks and accelerates the process of its destruction. This embodiment of the bit allows an increase in the mechanical drilling rate. Claim drill bit, containing sections with trunnions on which conical roller cones are mounted with bearings with rims reinforced with carbide teeth with a working head in the form of a spherical segment with an inclined edge, characterized in that, in order to increase the mechanical drilling speed, carbide teeth of the peripheral segment the crown is oriented with a flat face at an angle of 40-50 ° to the generatrix of the cone, while the angle of inclination ot of the flat face to the axis of the clove is determined by the formula gJ H where and is the diameter of the clove , mm; H - the height of the working head, mm. Sources of information taken into account during the examination 1. USSR author's certificate No. 202026, cl. E 21 V 10/16, 1964. 2. The patent of France No. 2403446, cl. Е 21 В 9/36, published. 1979 (prototype). / FIG. 2 Phage.