RU2513650C2 - Multistep rolling cutter drilling tool - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to well boring. Proposed tool comprises multistep cutters. Note here that separate leading teeth row is spaced from subsequent row of the other cutter in bit axis by (0.04-0.06)D with step width of (0.02-0.04)D, where D is tool diameter, said ratios being maintained at cutter outer cones.

EFFECT: higher rate of drilling owing to horizontal and vertical cutting to make stepped surface with steps to be destructed during their formation.

6 dwg

Description

The invention relates to a rock cutting tool used in well drilling, and in particular, to a drilling tool in which rock destruction is carried out by means of a cone: cone burgole for core sampling, cone reamers, cone stabilizers and cone bits.

Known cone drilling tool, in particular cone bits, including cones, the working surface of the armament of the crowns of which (teeth) are described by the generators of the cones, and the generatrix of these cones is in the plane of pure rolling [1] (analog).

In the well-known cone drilling tool, during its operation, cone teeth destroy the rock in an ineffective way - by pressing it with insignificant sliding into the surface of the face. The latter indicates the ineffective destruction of rocks in the absence of a cutting effect, similar in type to the destruction of the rock to break.

These shortcomings have been partially eliminated in multi-stage roller cone drilling tools and, in particular, in multi-stage roller cone bits, the armament of which is formed by two cones.

The well-known multi-stage cone drilling tool (chisel) [2], adopted as a prototype, includes two-cone cones, the working surface of the armament (teeth) of each crown on the cones adjacent to the axis of the bit is made perpendicular to the axis of the tool, which determines the multi-stage armament, and arming of peripheral cones describes them generators, i.e. armament is made stepless.

In the well-known multi-stage rolling-cutter drilling tool (chisel) during its operation, the drilled rocks are destroyed by pressing the armaments of individual rims of the peripheral cones into the face with minimal sliding (cutting) along the tangent in the plane of the face, with the same destruction by step weapons of cones close to the axis of the bit, including partial cleavage (destruction by cutting) in the vertical direction of the steps in the process of their formation. Peripheral cones destroy 3/4 of the face. Due to the ineffective stepwise destruction of rocks by arming the cones close to the axis of the tool, the cones and the ineffective destruction of the stepless armament of the peripheral cones of the cone, the drilling tool produces ineffective advancement of the face with increased energy costs.

The aim of the invention is to increase the mechanical drilling speed by increasing the amount of fracture by cutting in the horizontal direction and introducing into the drilling process the destruction of rock by cutting in the vertical direction by forming a side open stepped surface with steps completely destroyed during their formation.

This goal is achieved by the fact that in the well-known multi-stage cone drilling tool, a separate leading crown of any cone is removed from the subsequent other cone along the axis of the bit by 0.04-0.06D with a step width of 0.02-0.04D, where D is the diameter of the tool, with the preservation of these relations on the outer cones of cones.

The combination of the distance along the axis of the drilling tool of the leading crowns of any cone from the subsequent ones of 0.04-0.06D and the step width of 0.02-0.04D creates such circumstances of the destruction of the face when the stepped surface is destroyed in the process of its formation, which provides favorable conditions for work weapons instrument with minimal energy consumption for the destruction of rock

Figure 1 shows a multi-stage roller cone drilling tool (double-cone bit) in accordance with the prototype [2] with ideal step sizes when its arms (teeth) interact with the formed bottom hole: 1 - roller cone drilling tool paw; 2 - cone; 3 - armament of crowns of cones (teeth); 4 - rocks that make up the face.

Figure 2 shows the cone of a stepped cone drilling tool (real three-cone bit) during the interaction of its armament (teeth) with the formed bottom hole: 1 - paw of the drilling tool; 2 - cone; 3 - armament of crowns of cones (teeth); 4 - rocks that make up the face.

Figure 3 shows the total working surface of the armament of the three cones of the drilling tool (real bit), where the separate leading crown of the peripheral cone of any cone is removed from the subsequent along the axis of the bit by (0.04-0.06) D with a step width (0.02 -0.04) D; 3 - armament of crowns of cones (teeth); 0-0 - axis of rotation of the drilling tool; 0′-0 ′ is the axis of rotation of the cone; 0 ′ ′ - 0 ′ ′ is the instantaneous axis of rotation of the cone in the plane of pure rolling.

Figure 4 shows the profiles of individual I, II and III th cones: 3 - armament of crowns of cones (teeth); 0-0 - axis of rotation of the bit; 0′-0 ′ is the axis of rotation of the cone; 0 ′ ′ - 0 ′ ′ is the instantaneous axis of rotation of the cone in the plane of pure rolling.

Figure 5 presents full-size three-cone bit 3E215,9T-PV, made in accordance with the claimed invention.

Figure 6 shows a graph of the dependence of the drilling speed on the rotational speed of the bit at a constant load of 20 · 10 kN during the testing of the 3E215.9T-PV bit relative to serial bits of the type "M" and "T".

As can be seen from Fig. 1, a multi-stage cone drilling tool with stepped weapons 3 destroys rocks 4 solely by sliding (cutting) tangentially to the rotation of the bit in the plane of the face and chipping (breaking by cutting) in the vertical direction of the steps formed on the face. Arming the cones closest to the axis of the drilling tool does additional work to destroy the rock cone 4 formed along the axis of the well. Fracture by cutting, corresponding to tear fracture, for rocks is an order of magnitude more effective than fracture by indentation and compression. Destruction of steps completely destroyed during their formation during operation of a drilling tool, in which a separate leading crown of any cone is removed from the subsequent other cone along the axis of the bit by (0.04-0.06) D with a step width (0.02-0, 04) D, where D is the diameter of the tool, in terms of energy consumption is two times lower than the destruction of a flat face. Established by the author analytically and experimentally.

Thus, an increase in the mechanical drilling speed is achieved by increasing the volume of fracture by cutting in the horizontal direction and introducing into the process of drilling the fracture by cutting in the vertical direction by forming a side open stepped surface with steps that are completely destroyed in the process of their formation with minimal energy costs

These results apply equally to the operation of cone burgheads for coring, cone reamers, cone stabilizers and cone bits.

Ratios of the distance of a single leading crown of any cone from the subsequent crown of another cone along the axis of the bit by (0.04-0.06) D with the step width (0.02-0.04) D, where D is the diameter of the tool, determined by the depth of the well being drilled : shallow wells require lower ratios, deep ones require large ratios.

For real bits, the same ratios can be completely preserved on the peripheral cones with the maximum possible step increment on the cones close to the axis of the drilling tool (Figs. 2-5).

The multi-stage cone of the drilling tool in figure 2, having a stepped surface of weapons 3, completely destroys the steps formed on the rock 4, creating a stepless face.

The total working surface of the weapons of the three cones of the drilling tool (real bit) in figure 3 shows the complete overlap of the face.

During the operation of the drilling tool (three-cone bit), the maximum leading crown (crown C of the cone in Fig. 4) forms an annular groove on the bottom of the well, creating a side open stepped surface on both sides, which facilitates the working conditions of the subsequent crowns I and II th cone. These crowns, in turn, become leading for the two crowns of the 3rd cone, for which they also form an open stepped surface. From the side of the periphery of the face, a stepped surface is formed with steps of such dimensions that are destroyed in the process of their formation with minimal energy costs, and completely destroyed, which creates the conditions for the work of advanced weapons. With such destruction, a much larger volume of destroyed rock is per unit of energy expended than in the case of destruction of a flat face.

The full-scale multi-stage three-cone bits 3E215,9T-PV in figure 5 are made by a small industrial batch in accordance with the claimed invention and tested on shallow blast holes in Ukraine and in an oil well in the Samara region.

When tested in the quarries of the Dokuchaevsky flux-dolomite plant, the bits showed an increase in drilling speed of 300% (Fig.6). When tested in an oil well on a turbodrill, an emotional assessment of the driller was received: “What is the bit? The tool just fails! ”

Information sources

1. Paliy P.A., Korneev K.E. Drill bits, M., "Nedra", 1971, 446 p. (analogue).

2. U.S. Patent No. 2032575 Roller bit, March 3.1936. G.G. Harrington.

Claims (1)

Multistage roller cone drilling tool (burgole head, expander, stabilizer, chisel), including multistage roller cones, characterized in that, in order to increase the mechanical drilling speed by increasing the fracture volume by cutting in the horizontal direction and introducing the rock destruction by cutting in the vertical direction into the drilling process by forming a side open stepped surface with steps that are completely destroyed during their formation, a separate leading crown of any cone is removed from the subsequent other cone along the axis of the bit by (0.04-0.06) D with a step width (0.02-0.04) D, where D is the diameter of the tool, while maintaining these ratios on the outer cones of the cones.

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