RU2450113C1 - Crown bit - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: crown comprises a crown ring with slots at the end, where hard-alloy plates of rectangular shape are fixed with through channels. Each plate is made with one diagonal link that connects a lower well-calibrating section of the plate with its upper core-calibrating section, at the same time in plan it has a shape of a trapezoid, the larger base of which is arranged at the side of well wells, at the same time hard-alloy plates in plan have a shape of a trapezoid, the larger base of which is located at the side of the well walls.

EFFECT: application of the proposed crown makes it possible to considerably simplify the technology of cutters manufacturing with simultaneous improvement of their quality and therefore to increase efficiency of its operation and to reduce cost of drilling works.

2 cl, 3 dwg

Description

The invention relates to a rock cutting tool, namely to drill bits intended for destruction, mainly abrasive and alternating in hardness of rocks.

A drill bit is known that includes a body with rock cutting inserts consisting of a base plate, core, core and borehole cutters with a stepwise arrangement and with a shift of the core and core and borehole cutters in the radial plane (see ed. St. USSR No. 530941, class E21B 10/02, 1976).

The disadvantages of this crown include the difficulty of mounting the inserts in the housings, which inevitably reduces the quality of the products and reduces their technical and economic indicators.

A drill bit is also known, including a crown ring with grooves at the end, in which rock-cutting inserts are fixed, containing carbide cutters in the form of thin-walled plates fixed to the front face of the support plate by means of a wrapping plate (see Kornilov N.I. et al. Rock-cutting tool for exploration wells.M .: Nedra, 1979, p.168-170).

The disadvantage of this crown is the small scope, because it works effectively only on abrasive rocks. When drilling intermittent rocks, the technical and economic performance indicators are sharply reduced.

Closest to the proposed technical essence and the achieved result is a drill bit containing a core ring with a connecting thread and grooves on the end, in which rectangular carbide inserts with through holes are fixed (see ed. St. USSR No. 130414, class Е21В 10 / 02, 1960).

The disadvantage of this crown is its low efficiency, due to the suboptimal scheme of using the resource of carbide inserts. Another disadvantage of it is the difficulty of manufacturing in the presence of a large number of holes, for each of which it is necessary to use a separate punch. All this reduces the technical and economic performance of the crown.

In connection with the stated technical result of the invention is to reduce the cost of drill bits and increase their technical and economic indicators.

The specified technical result is achieved in that in a drill bit containing a core ring with a connecting thread and grooves at the end, in which rectangular carbide inserts are fixed with through channels, according to the invention, each plate is made with one diagonal jumper connecting the lower borehole section of the plate with the upper its core-calibrating section.

The task is also facilitated by the fact that each carbide plate in the plan has the shape of a trapezoid, the larger base of which is located on the side of the well walls.

The invention is illustrated by the drawing, in which figure 1 depicts a General view of the crown in section, and figure 2 and 3 carbide plate in two projections on an enlarged scale.

The drill bit includes a core ring 1 with a connecting thread 2 and radial grooves 3 at the end, in which rectangular carbide inserts 4 are fixed with through holes 5. Each plate 4 is made with one diagonal jumper 6 connecting the lower bore section of the plate 4 with the upper core calibrating it plot. Moreover, in terms of carbide plates 4 has the shape of a trapezoid, the larger base 7 of which is located on the side of the walls of the well, and the smaller base 8 is on the side of the core. The larger base 7 of the trapezoid when drilling through elastoplastic rocks (limestones, mudstones, marble) can be made with longitudinal notches 9 and equipped with diamond-containing crumbs.

This embodiment of carbide inserts 4 and their arrangement ensures uniform armament of the crown end along the radius. As you know, the most labor-intensive sections of the bottom of the well for destruction are borehole and core-forming zones. In the proposed crown, it is these sections that have the maximum armament in the form of vertical posts 10 involved in the calibration of the walls of the well and core. Given that the bore-forming sections have a larger volume, carbide inserts 4 are oriented by a large base 7 towards the side of the borehole. The implementation of carbide inserts 4 with just two holes allows to simplify the technology of their manufacture and reduce cost due to the reduction of auxiliary devices. The presence of a diagonal jumper 6 on the one hand enhances the armament of the crown, and on the other hand, these jumpers 6 enhance the strength of carbide plates 4.

The use of the proposed crown can significantly simplify the manufacturing technology of both carbide inserts and the crown as a whole, and thereby reduce the cost of drilling. Owing to a more optimal reinforcing pattern of crowns, their technical and economic indicators also increase.

Claims (2)

1. A drill bit containing a core ring with a connecting thread and grooves at the end, in which rectangular carbide inserts are fixed with through channels, characterized in that each plate is made with one diagonal jumper connecting the lower bore section of the plate with its upper core-calibrating section. 2. The drill bit according to claim 1, characterized in that each carbide plate in plan has a trapezoid shape, the larger base of which is located on the side of the well walls.

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