RU2166602C1 - Turbo-drill - Google Patents

Abstract

FIELD: equipment drilling deep boreholes. SUBSTANCE: turbo- drill for deep boreholes has body-rotor in which rotor stages of pressure of turbine, rotor members of radial supports and rotor members of axial thrust are anchored fixedly. Stator stages of pressure, stator members of radial supports, stator members of axial thrust and lantern are fixed on axle of turbo-drill with the help of nut-adapter. Core-taking body is joined to lower thread of adapter and core-forming bit is attached to lower thread of core-taking body. Internal drill bit is linked to lower thread of nut- adapter. Axle of turbo-drill is attached with its upper end to lower pipe of drill pipe string. EFFECT: increased efficiency and productivity of drilling thanks to enhanced speed of rotation of core-forming bit. 4 cl, 2 dwg

Description

 The invention relates to the field of technology, which is used for drilling oil and gas wells and in a narrower unit - to downhole motors - turbodrills, which rotate the bit, destroying the bottom of the wells.

 An analogue of our invention is a core turbo chisel with a rotating rotor body (see R.A. Ioannesyan "Fundamentals of Theory and Technology of Turbine Drilling", Gostoptekhizdat, 1953, Moscow, p. 137). However, the design of this turbo bit did not allow to destroy the core formed during drilling, since a core-receiving pipe passed through the lower end of its hollow axis to the cone of the drill head.

 The closest analogue of our invention is a tool made according to the patent of the Russian Federation N 2100559 (12/27/97, bull. N 36).

 This patent describes a turbo-drill, the casing of which is rotated by the rotor of the drilling rig through a drill pipe string, at the lower end of which it is fixed.

 A diamond core-forming crown is fixed on the lower end of the turbodrill body. The internal bit, "recessed" in the turbodrill body, is fixed on the lower end of its shaft. The purpose of the internal bit is to drill a core drilled with a diamond crown. The only, but very serious drawback of the closest analogue is the fact that, for reasons of the strength of the drill string, the case diamond core cannot be rotated with a frequency of more than 120-250 rpm. This circumstance is the main reason limiting the mechanical drilling speed, and therefore its effectiveness.

 This invention allows to remove this restriction and makes it possible to raise the frequency of rotation of the housing crown to a level of 1000-1500 rpm At the same time, the efficiency of the internal core-destructing bit is also increased, since it can be performed cone with sealed supports.

 The essence of the invention lies in the creation of a turbo-drill, the rotating rotor body of which has a core-forming crown connected with it, fixed with a thread on the lower end of the core-receiving body, which is fixed with its upper end to the lower thread of the connecting adapter of the turbo-drill body. The shaft of the turbodrill with its upper end is fixed to the lower pipe of the drill string; at its lower end, using a thread of a nut-sub, a chisel is mounted, which is located inside the core receiver body.

 The distance from the lower end of the core-forming crown to the rock-cutting surface of the inner bit connected to the turbo-drill shaft by means of a sub-nut is selected within the range of values from one to ten meters. A similar design of the turbodrill allows most of the bottom hole area represented by the "tower" - the core string to not be drilled, but crushed and broken, which significantly increases the efficiency of the wellbore deepening process.

 The invention is illustrated by drawings.

 In FIG. 1 shows a general assembly of a turbodrill. In FIG. 2 - section "AA" turbodrill.

 The upper nipple sub 1 of the housing 2 of the turbodrill and the lower connecting sub 3 due to the axial compression force are mounted in the housing 2 of the rotor pressure stage 4 of the turbine; rotor elements 5 of one or more radial bearings and thrust bearings 6. The shaft 7 of the turbodrill is fastened with its upper threaded end to the lower pipe 8 of the drill string.

 On the shaft 7 of the turbodrill with the help of a sub-nut 9, the stator stages of pressure 10 of the turbine are attached; stator elements 11 of radial bearings; discs 12 of the axial heel; lantern 13. In its upper part, the shaft of the turbo-drill 7 has an internal cavity 14, which hydraulically connects the internal cavity of the drill string to the turbine cavity 15 of the casing 2 through the windows 16 and the lantern 13 of the shaft 7. The spacer sleeves 17 of the disks 12 of the axial heel allow fixing the casing 2 of the turbo-drill on its shaft 7 with an axial play of up to 14 mm. An internal chisel 18 is attached to the lower end of the adapter nut 9 on the thread. The adapter nut 9 has windows 19 that hydraulically connect the internal cavity of the adapter nut 9 to the turbine pressure stages. To the lower connecting sub 3 of the housing 2 of the turbodrill, a core receiving housing 20 is attached to the thread, which has longitudinal or spiral grooves 21 on its inner surface (see Fig. 2). A core-forming diamond or polycrystalline diamond crown 22 is attached to the lower end of the core receiver body 20 on the thread.

 The rotor 4 and stator 10 stages of the turbine are made with blade crowns either of high or low circulating type, which provides a change in the coefficient of hydraulic resistance of the turbine in functional connection with the rotational speed of the rotor body of the turbodrill.

 Work turbodrill.

 A turbodrill in the complex of all the elements of its construction described above, mounted on the end of the drill string, is led to the bottom of the well, after which the mud pumps are turned on. The usual drilling process begins, in which the drill string with a frequency of 15-60 rpm is rotated by the rotor of the drilling rig, rotating the shaft 7 of the turbodrill, which is fastened with its upper end to the bottom pipe of the drill string. The turbodrill rotor housing rotates on its shaft 7 with a frequency of up to 1500 rpm. A core-forming diamond crown 22 begins to drill a “tower” -column of large-diameter core, which begins to enter the core receiver 20; so until it comes into contact with the inner bit 18. Up to this point, the turbodrill body 2 is in the extreme “lower” position, in which the thrust bearings 6 rest on the upper end surface of the axial heel disks 12 with their lower end face. The driller monitors the frequency mode of the turbodrill by the pressure on the pump outlets. At the moments when the rotor of the turbo-drill reaches the operating modes close to idle rotation frequencies, the driller sharply delivers the tool to the face by 10-50 mm.

 At the same time, the inner bit 18 rotating with a low frequency compresses the core column with a large longitudinal force, breaks and crushes it. Numerous cracks and punctures are formed in the core, through which drilling fluid and its filtrate penetrate into it. Cracks and fluid filtered into the core repeatedly weaken and disintegrate it even more, which in turn significantly increases the efficiency of the bit 18 in its final destruction. The core fragments through the grooves 21 of the core receiver body 20 and the flushing channel of the crown 22 by the flow of drilling fluid (passing through the pressure stages 4 and 10 of the turbine; through the windows 19 of the adapter nut 9 and its internal cavity and then through the central flushing channel of the bit 18) are carried out into the annular space behind the body 2 of the turbodrill. Thus, the mechanism that limits the mechanical drilling speed is a diamond crown 22, which the turbodrill rotor body rotates with a frequency of 4 to 10 times greater than that of the closest prototype analogue.

Claims (5)

 1. A turbo-drill, comprising a housing in which a shaft, rotor and stator pressure stages of a turbine, rotor and stator elements of radial bearings and an axial heel, a lantern, through which the internal cavity of the shaft, connected with the internal cavity of the drill pipe, are hydraulically connected through windows, made in the upper part of the shaft, with a turbine cavity inside the body, a core-forming crown connected to the body, and a bit associated with the turbo-drill shaft, characterized in that the turbo-drill shaft is mounted on the lower drill pipe In this case, the rotor pressure stages of the turbine, the rotor elements of the radial bearings and the axial heel are fixedly fixed in the turbodrill housing with the help of a nipple nut and a connecting sub, and the turbodrill shaft is connected to a bit placed inside the core receiver body by means of an adapter nut, by means of which on the shaft the stator stages of the turbine pressure, the stator elements of the radial bearings and the axial heel are fixedly fixed, and the core receiving housing is fixed to the lower thread of the connecting adapter of the turbobu housing a.  2. The turbo-drill according to claim 1, characterized in that its core receiver body has longitudinal or spiral grooves on its inner surface.  3. The turbo-drill according to claim 1, characterized in that the sub-nut has windows hydraulically connecting its internal cavity to the pressure levels of the turbine.  4. The turbodrill according to claim 1, characterized in that the pressure stages of the turbine are of low circulation or high circulation type.  5. The turbodrill according to claim 1, characterized in that its rotor housing has axial play relative to its shaft up to 14 mm.

Images