RU2244795C1 - Device for drilling slanting-horizontal wells - Google Patents

Abstract

FIELD: mining industry.

SUBSTANCE: device has two bodies, laced between drilling pipes and rock-destroying element, drilling assembly changing assembly, mounted between bodies. Bodies are placed at a space between each other and interconnected moveably by drill angle changing assembly, made in form of bushing, inside of which a rubber bushing is placed, passing through inner hollows of bodies. Rubber bushing is provided with compacting element and elements for excluding its deformation. Value of space is selected from condition providing for drilling along planned trajectory, providing for exit from slanting portion into horizontal. Elements for excluding deformation of rubber bushing are made in form of steel rings. Fixing elements are made in form of two pairs of coaxial stops in lower and upper bodies respectively at angle of 90° to each other.

EFFECT: higher productiveness.

2 cl, 1 ex, 1 dwg

Description

The invention relates to a device for drilling wells and is intended for rotary drilling of horizontal horizontal multilateral wells to the productive horizons of multilayer deposits of solid minerals, followed by the extraction of solid minerals from thin substandard formations using well technology.

A device for drilling horizontal wells, comprising a tubular body, a deflecting element located in its cavity, a hollow shaft located in the body with the possibility of interaction with the deflecting element, the upper end of the shaft is rigidly connected to the body, and the lower is mounted on a hinge support ( SU, Aut. St. N1469075, E 21 B 7/08, 04.21.87).

This device has limited operational capabilities, because, firstly, it does not allow changing the direction of the well in the azimuthal direction, and secondly, the specified direction is maintained only when drilling with constant axial load.

A device for drilling inclined horizontal wells is known, having in the case with surfaces centering relative to the axis of the wells a hollow shaft consisting of upper and lower sections, a shaft change unit with the possibility of axial movement and a spring-loaded coupling with respect to the lower section of the shaft (see US patent N4895214, E 21 V 7/08, 90.01.23).

The device has limited operational capabilities due to the design features of the control unit for the direction of drilling, which does not have a reliable fixation of the body and, therefore, does not guarantee a given direction of the well. In addition, this device requires two modes of pumping the drilling fluid, working and control, to translate it into working position, which in turn causes an increase in energy costs.

Closest to the claimed device is a device for directional drilling, comprising a hollow shaft, a housing mounted concentrically rotatably on the shaft, support elements mounted on the outer surface of the housing, and a housing control assembly. The shaft is made up of one of the upper and lower sections, located at an angle relative to one another, and the housing control unit contains a coupling located between the shaft sections and spring-loaded relative to the lower section, which is mounted with the possibility of axial movement and has an annular groove on the outer surface with a groove for interacting with a locking finger fixed to the housing (see RF patent No. 2112128, IPC E 21 B 7/08).

The disadvantage of this device is the inability to drill in a short arc from an inclined section of the well into a horizontal section of the reservoir. In addition, the presence of an external rigid body, bent at an angle α, leads to a decrease in the strength characteristics of the nodes of the device when drilling wells of small diameter.

The objective of the proposed device is the implementation of drilling in a short arc from an inclined section of the well into a horizontal section of the reservoir.

The problem is solved in that the device for drilling inclined horizontal wells, comprising two bodies located between the drill pipes and the rock cutting element, a node for changing the drilling angle installed between the bodies, according to the invention, the bodies are located with a gap relative to each other and are interconnected movably by means of a node for changing the drilling angle, which is made in the form of a sleeve, inside of which is placed a rubber sleeve passing through the internal cavities of the housings, while the rubber the sleeve is equipped with a sealing element and elements to prevent its deformation, and the gap value is selected from the conditions for ensuring drilling along the calculated path.

Elements to prevent deformation of the rubber sleeve are made in the form of a set of steel rings, and fasteners are made in the form of two pairs of coaxially arranged stoppers in the lower and upper bodies, respectively, at an angle of 90 ° to each other.

The originality of the proposed solution lies in the fact that the device eliminates the need for an external rigid body, bent at an angle α, which allows us to prevent the weakening of the strength characteristics of the nodes of the device when drilling small diameters.

The invention is illustrated in the drawing, where:

1 - upper case;

2 - lower case;

3 - sleeve;

4 - stopper;

5 - rubber sleeve;

6 - end stop;

7 - a chisel;

8 - drill pipe;

9 - deviated well section;

10 - a set of steel rings;

11 - face;

12 - an epiploon.

The device for drilling inclined horizontal wells consists of two detachable movable casings - the upper 1, which is connected to the drill pipes 8, and the lower 2, which is connected to the bit 7. The upper housing 1 and the lower housing 2 are interconnected by a movable sleeve 3, through four stopper 4, two of which are coaxially located in the upper case and two in the lower case. The planes of these pairs of stoppers are located relative to each other at an angle of 90 degrees. In the body of housings 1 and 2, the stoppers 4 are fixedly mounted, and the movable sleeve 3 can oscillate around the stoppers 4. The stopper 4 and the movable sleeve 3 are connected through the bodies to the drill pipes 8 and the bit 7. The cases are located with a gap (c) relative to each other , which allows you to create the appropriate angle of inclination α for drilling along the calculated trajectory, flattening the inclined section of the well in horizontal in a specific geological section. To calculate the gap value, the following relation can be used: c = 2D Sin α / 2, where D is the diameter of the body, α is the maximum angle between the bodies at the moment of contact of the end parts, which is equal to the central angle of the regular polygon described by a circle of radius R along the path which is flattening. Moreover, α = 360 °: n, where n is the number of sides of the correctly described polygon and is equal to the sum of the lengths of the lower part of the body and the rock cutting tool (chisel). The selected calculated value of the angle is provided by focusing on one of the sides of the end parts of the cases.

A device for drilling inclined horizontal wells works as follows. The movable sleeve 3 makes free oscillatory movements around the stoppers 4 within the boundaries of the inner cavity of the upper 1 and lower 2 of the housing. Through the stoppers 4 and the movable sleeve 3, rotation is transmitted from the rotor through the drill pipes 8 to the bit 7 at a design angle α. To supply flushing fluid through the drill pipe 8 to the bit 7 and then to clean the bottom, inside the upper body 1, lower body 2, movable sleeve 3 insert a rubber sleeve 5, equipped with a spacer sealing gland 12, a set of steel rings 10 that do not allow deformation of the rubber bushings 5. The fixation of the calculated value of the deflection angle α occurs due to end stops 6 of the upper 1 and lower 2 of the housing. In the process of lowering the device on the drill pipe 8 along the wall of the inclined section of the well 9, the device approaches the bottom 11 at an angle α. During drilling along a short arc to exit from the inclined section to the productive horizon, the inclined section is flattened towards the horizon by the corresponding calculated angle α. The azimuth is set by the inclined section and it is preserved at the entrance to the horizon of the reservoir.

Example.

With the actual geological occurrence of the reservoir (the depth of which is determined by preliminary drilling of the leading well) by 40-50 m, the radius of the calculated trajectory is about 20 m. The diameter of the body is 0.165 m, the length of the lower part of the body with a bit of 0.7 m, with n = 180, and the angle α = 2 °, i.e. the gap in the static state between the bodies will be 2.8 mm, and with a maximum opening of the bodies to the stop 5.6 mm.

Claims (2)

1. A device for drilling inclined horizontal wells, comprising two bodies located between drill pipes and a rock cutting element, a node for changing the drilling angle mounted between the bodies, characterized in that the bodies are located with a gap relative to each other and are interconnected movably by means of a change unit the drilling angle, which is made in the form of a sleeve, inside of which is placed a rubber sleeve passing through the internal cavities of the housings, while the rubber sleeve is equipped with a sealing element ntom elements and to avoid its deformation and the magnitude of the gap is chosen from the condition for providing the required trajectory drilling, exits from the inclined portion to the horizontal. 2. The device according to claim 1, characterized in that the elements for eliminating the deformation of the rubber sleeve are made in the form of a set of steel rings, and the fasteners are made in the form of two pairs of coaxially arranged stoppers in the lower and upper cases, respectively, at an angle of 90 ° to each other .