RU2579087C1 - Bit for jet-turbine drilling - Google Patents

Abstract

FIELD: mining.

SUBSTANCE: invention relates to the field of drilling wells of large diameter, namely, to bore bits for reactive turbo-drilling (RTD) of roller type. Bore bit for RTD comprises a body with inclined trunnions fixed on which there are cutters with peripheral, intermediate and apical rims equipped with milled, cast or hard-alloy toothed cutting structures. All cutter rims have teeth differently directed relative to the cutter axis. Peripheral rim teeth inclination angle is opposite to the inclination angle of teeth of other rims. Torques simultaneously created by simultaneously sliding teeth of peripheral and other rims on each cutter at the moment of its maximum axial sliding caused by rotation of RTD unit, when its rotation axis is located along the direction of RTD unit rotation, are connected by a certain correlation.

EFFECT: technical result consists in increase of sinking and mechanical speed of drilling by RTD method.

1 cl, 4 dwg

Description

The invention relates to the field of drilling of large diameter wells, namely to bits for reactive turbine drilling (RTB) cone type.

A bit for RTB is known, containing a body with inclined trunnions and cones fixed on them with main and peripheral crowns reinforced with carbide teeth and a calibrating surface (see Zhilenko N.P. et al. Reference Guide for Jet Turbine Drilling, M .; Nedra , 1987, p. 77-81, Fig. 42).

The disadvantage of this bit is the high energy intensity of the rock destruction process due to the irrational arrangement of the teeth, as well as the increased consumption of hard alloy, leading to an increase in the cost of 1 m of penetration.

The closest to the proposed technical essence and the achieved result is a jet-turbine drilling bit containing a body with inclined pins and cones fixed to them with stepwise arranged crowns, of which the top and main are leading (see RF patent No. 2090733, cl. ЕВВ 10/16, 1997).

The disadvantage of this bit is the low efficiency of their work. This is due to the fact that the design of these bits does not fully take into account the features of operation during RTB associated with the movement of cones not only around the trunnions, but also in the portable movement of the bit around the axis of rotation of the RTB unit.

In accordance with the stated technical result of the invention is to increase the penetration and mechanical drilling speed by the RTB method.

The specified technical result is achieved by the fact that in the drill bit for RTB, containing a housing with inclined trunnions, on which the cones with milled, cast or carbide gear arms are fixed, according to the invention, all cones of the cones are made with teeth opposite to the cone axis, and the peripheral crowns are opposite directional angle of inclination of the teeth compared to the angle of inclination of the teeth of other crowns, while the torques created simultaneously by the sliding inclined teeth of the periphery malarial and other rims on each cone, at the point of maximum axial sliding due to the rotation of RTB unit when its rotation axis is along the machine direction of rotation RTB are related by

where M _P - torque created by the teeth of the peripheral crown; M _In - torque created by the teeth of the crown; M _OS - torque created by the teeth of the intermediate crowns.

This implementation of the geometry of the armament of the bit minimizes the rotation of the cone under the action of the torque that occurs when the inclined teeth of the cone cone along the axis of rotation slip during the movement of the bit associated with the rotation of the RTB unit, and thereby allows to increase the total area of destruction of the bottom due to the maximum using the work of the runaway and run-down faces of all teeth without exception, which are simultaneously in contact with the surface of the face.

In FIG. 1 shows a general view of a bit with multidirectional helical gear for RTB; in FIG. 2 shows a schematic diagram of the motion of the cone during RTB, in FIG. 3 is a diagram of the defeat of the face by spur and helical arms of cones in the place of maximum slippage along the axis of the cone in the direction of movement of the RTB assembly .; in FIG. 4 is a schematic diagram of helical cone gear for RTB.

The RTB bit includes a body 4 with inclined trunnions 5, on which cones 6 with top 3, main (intermediate) 2 and peripheral 1 crowns are mounted, equipped with multidirectional milled or cast steel teeth or carbide teeth.

All the cones of the cones are made with different directions (see the example in Fig. 4) with respect to the cone axis with teeth (for example, at angles α, β, γ). As shown in FIG. 4, the peripheral crowns have an angle α of inclination of the teeth directed in the opposite direction compared to the angles of inclination β and γ of the teeth of other crowns. In this case, the torques created by simultaneously sliding the inclined teeth of the peripheral and remaining crowns on each cone, at the moment of its maximum axial sliding, caused by the rotation of the RTB unit, when its axis of rotation is located along the direction of rotation of the RTB unit, are related by

where M _P - torque created by the teeth of the peripheral crown; M _In - torque created by the teeth of the crown; M _OS - torque created by the teeth of the intermediate crowns.

The principle of operation of the bit is as follows. The RTB unit, which includes several parallel-working turbodrills with bits, is lowered into the well and the drilling process begins. Under the influence of axial load and torque transmitted to the bit from the RTB unit, carbide teeth or steel teeth are introduced into the rock and destroy it. In this case, the armament of the bit performs relative rotation around the pins 5 (Fig. 1) and the portable movement around the axis of rotation of the unit for RTB. The latter is accompanied by a significant slippage of the weapons of the cone 6 along the bottom of the well, both along the axis of the cone and in the perpendicular direction.

- вектор линейной скорости точек А и В). При этом зубчатые элементы вооружения (в случае прямозубого вооружения шарошек), находящиеся в соприкосновении с забоем, расположены таким образом, что их режущая кромка так же направлена вдоль направления вращения агрегата. Поэтому, при «перекатывании» шарошки долота по забою в точках А и В происходит максимальное проскальзывание зубьев вооружения по забою в направлении вращения агрегата РТБ. Характерной особенностью этого проскальзывания является то, что зубья вооружения шарошки скользят в направлении не их основных рабочих поверхностей, т.е. набегающей или сбегающей граней зубьев, а в перпендикулярной им плоскости. Таким образом, в точках А и В основное разрушение породы забоя, связанное с проскальзыванием вооружения, осуществляется либо торцевыми поверхностями зубьев, обращенными к основанию шарошки и ее тыльным конусом, либо торцевыми поверхностями зубьев, обращенными к вершине шарошки.In FIG. Figure 2 shows the movement of the weapon of the cone at the moment of “rolling” it at points A and B. Here, the movement of the bit around the axis of rotation of the unit cannot be compensated for by an additional increase or decrease in the speed of rotation of the cone, since its axis of rotation is located along the direction of rotation of the unit ( $${\overrightarrow{V}}_A$$

is the linear velocity vector of points A and B). In this case, gear elements of armament (in the case of spherical cone armaments) in contact with the face are arranged so that their cutting edge is also directed along the direction of rotation of the unit. Therefore, when “rolling” the bit cutter along the face at points A and B, the maximum teeth slippage of the weapons along the face occurs in the direction of rotation of the RTB unit. A characteristic feature of this slippage is that the teeth of the cone arms glide in the direction not of their main working surfaces, i.e. the running or running edges of the teeth, and in a plane perpendicular to them. Thus, at points A and B, the main destruction of the face rock associated with the slipping of weapons is carried out either by the end surfaces of the teeth facing the base of the cone and its rear cone, or by the end surfaces of the teeth facing the top of the cone.

In (Fig. 3.1), a diagram of the bottom face defeat by the straight-cutter arms of the cone located at point B. In this case, the total area of the bottom strike by the cone arms in the horizontal plane will be determined as the sum of the areas of the rectangles formed by the width of the tooth end part a and the slip value Δ. As can be seen in the diagram, the effectiveness of weapons in this direction is minimal. Significantly increase the area of destruction of the face and thereby increase the efficiency of drilling can be done by equipping the cone with helical gear (Fig. 3.2).

To assess the increase in the area of destruction of the face when using helical gear in comparison with spur gear, you can by determining the difference in the area of the corresponding figures: S ₁ = a Δ; S ₂ = bΔ; S ₃ = S ₁ + bΔtgα (FIG. 3).

Equipping the cone with multidirectional helical arms makes it possible to significantly increase the area of impact of the face with the cone teeth, as well as to intensify the processes of removing drill cuttings from the rock destruction zone.

However, in order to maximize the effectiveness of helical-arms operation in RTB conditions, it is necessary, when designing weapons, to provide a certain orientation of the teeth of various weapon crowns (Fig. 4) by choosing the angle of inclination of the teeth to the axis of rotation of the cone of the corresponding crowns, where:

- сила воздействия породы на зуб периферийного венца шарошки, возникающая вследствие осевого проскальзывания шарошки. $$F_{\mathrm{one}}^{\mathrm{one}}$$

- the force of the impact of the rock on the tooth of the peripheral crown of the cone, resulting from axial slippage of the cone.

- сила воздействия породы на зуб промежуточного венца шарошки, возникающая вследствие осевого проскальзывания шарошки. $$F_{\mathrm{one}}^2$$

- the force of the impact of the rock on the tooth of the intermediate crown of the cone, resulting from the axial slippage of the cone.

- сила воздействия породы на зуб вершинного венца шарошки, возникающая вследствие осевого проскальзывания шарошки. $$F_{\mathrm{one}}^3$$

- the force of the impact of the breed on the tooth of the top crown of the cone, resulting from the axial slippage of the cone.

α, β, γ - the angle of inclination of the teeth to the axis of rotation of the cones of the respective crowns.

, $$R_1^2$$

, $$R_1^3$$

- осевые составляющие этих усилий, стремящиеся повернуть шарошку вокруг своей оси.Respectively $$R_{\mathrm{one}}^{\mathrm{one}}$$

, $$R_{\mathrm{one}}^2$$

, $$R_{\mathrm{one}}^3$$

- axial components of these efforts, seeking to rotate the cone around its axis.

In this regard, in order to prevent the additional rotation of the cone from the influence of these forces and thereby ensure the running and running edges of the teeth during their longitudinal movement, it is necessary that the following condition is met

Where:

, $$r_1^2$$

, $$r_1^3$$

- кратчайшие расстояния от оси вращения шарошки до точек приложения силы к соответствующим зубьям вооружения (фиг. 1). $$r_{\mathrm{one}}^{\mathrm{one}}$$

, $$r_{\mathrm{one}}^2$$

, $$r_{\mathrm{one}}^3$$

- the shortest distances from the axis of rotation of the cone to the points of application of force to the corresponding teeth of the weapon (Fig. 1).

That is, it is necessary that the torque acting on the cone from the side of one tooth, which is in interaction with the face rock, the peripheral crown, is approximately equal to the sum of the torques arising from the teeth of the intermediate and vertex crowns. Having transformed the approximate equality into a ratio of approximately equal to unity, with a sufficient degree of accuracy, we can say that in order to prevent the additional rotation of the cone from the influence of the rock forces on the teeth and thereby ensure the running and running edges of the teeth during their longitudinal movement, it is necessary that moments created simultaneously by the slanting inclined teeth of the peripheral and other crowns on each cone, at the moment of its maximum axial sliding due to rotation RTB unit, are related by

); М_В - крутящий момент, создаваемый зубьями вершинного венца (для примера на фиг. 4 $${М}_{В}={М}_{К1}^2$$

); М_ОС - крутящий момент, создаваемый зубьями промежуточных венцов (для примера на фиг. 4 $${М}_{ОС}={М}_{К1}^3$$

).where M _P - torque created by the teeth of the peripheral crown (for example, in Fig. 4 $$M_P=M_{\mathrm{TO}\mathrm{one}}^{\mathrm{one}}$$

); M _In - torque created by the teeth of the crown rim (for example, in Fig. 4 $$M_{\mathrm{AT}}=M_{\mathrm{TO}\mathrm{one}}^2$$

); M _OS - torque generated by the teeth of the intermediate crowns (for example, in Fig. 4 $$M_{\mathrm{ABOUT}\mathrm{FROM}}=M_{\mathrm{TO}\mathrm{one}}^3$$

)

Moreover, for the moment of maximum axial slip of the cone during RTB, it should be considered, as mentioned earlier, that the cone of the cone bit along the face at points A and B in FIG. 2, when the axis of rotation of the cone is located along the direction of rotation of the RTB unit.

Fulfillment of this condition will allow maximum use of the work of the runaway and runaway faces of all teeth, without exception, at the same time in contact with the surface of the face when slipping cone weapons associated with the rotation of the RTB unit.

Thus, the use of the proposed bit will increase the efficiency of drilling wells using the RTB method by increasing the destructive ability of weapons and reducing the energy consumption of the rock destruction process, which ultimately will make it possible to increase penetration and mechanical speed and reduce the cost of drilling operations.

Claims (1)

A jet-turbine drilling (RTB) bit containing a body with inclined trunnions, on which cones are mounted with peripheral, vertex and intermediate crowns equipped with milled, cast or carbide gear armaments, characterized in that all cones of the cones are made with different directions relative to the cone axis teeth, and the peripheral crowns have an oppositely directed angle of inclination of the teeth compared with the angle of inclination of the teeth of other crowns, while the torques created simultaneously creeping inclined teeth of the peripheral and other crowns on each cone, at the moment of its maximum axial sliding, due to the rotation of the RTB unit, when its axis of rotation is located along the direction of rotation of the RTB unit, are related by the ratio:

where M _P - torque created by the teeth of the peripheral crown; M _In - torque created by the teeth of the crown; M _OS - torque created by the teeth of the intermediate crowns.

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