SU929810A1 - Well-drilling apparatus - Google Patents

Description

(54) DEVICE FOR DRILLING WELLS

one

This invention relates to a technique for drilling wells, and more specifically to the drilling of small diameter exploration wells.

Flexible drill strings are known, consisting of an internal sealing chamber with hardening, a wire helix, load-carrying steel wires and an outer casing made of metal rings, which are separated by elastic gaskets 1.

However, when drilling small-diameter exploration wells, they cannot be used because of their bulkiness, as well as due to the fact that they are designed to work with downhole motors. Supported small-diameter downhole motors do not provide a high mechanical speed of drilling.

It is also known a device for drilling wells, comprising a flexible string of drill pipes, housed in a casing string and containing an internal power shell, an outer flexible tube made of separate rings, an adapter and a stabilizer located along the entire length of the flexible string 2.

The drawback of the device is that it does not possess sufficient stability when drilling straight and inclined wells.

The purpose of the invention is to increase the reliability of operation in drilling straight and inclined wells.

The goal is achieved by the fact that the stabilizer and the external flexible pipe are connected with the elements of the connection of the inner 10 power shell with the possibility of relative rotation, the casing string has longitudinal guides, and the outer surface of the stabilizer is the corresponding slots.

Claims (3)

 In addition, the cavity between the outer flexible tube and the inner power jacket is filled with lubricant. The inner force shell has two layers, formed by Z-shaped ribbons with opposite napravleem navyla, inside which is placed an elastic hose; The outer flexible pipe is formed by a tape with an S-shaped profile, stops are made on the connecting elements of the power shell, and the outer flexible pipe has reciprocal protrusions to interact with them. FIG. 1 shows the proposed device, the cut; in fig. 2 shows section A-A in FIG. 1. A device for drilling wells includes an adapter 1, which transmits rotation from the driving pole 2 of the drilling machine, located at the wellhead, to an internal flexible power sheath containing elastic sheath 3 and shells 4 and 5, wound in opposite directions. Shells 4 and 5 are made of Z-shaped tape with the opposite direction of winding. Each of these tapes may consist of several elastic (for example, metallic) threads. The adapter 1, through the support 6, interacts with the stabilizer 7, which keeps the outer tube 8 from rotating and falling into the well. The stabilizer 7 engages with the slots 9 mounted on the inner wall of the casing 10 with its grooves. The flexible pipe 8 is formed by an S-shaped ribbon profile Neighboring wound ribbons overlap each other in such a way that between them along the longitudinal axis of the column there is a gap whose optimum value is chosen from the relation C where P is the width of the tape, d is the diameter of the full pipe, R is the minimum required bending radius of the column. The stabilizer 7 and the outer flexible pipe 8 are connected with elements 11 of the connection of the inner power shell with the possibility of relative rotation, for example, using sub-supports 6. Elements 11 of the connection of the inner power shell have stops 12, and the outer flexible tube 8 has reciprocal protrusions 13. The individual links of the flexible string of drill pipes are interconnected in a single column using joints And and 14. The cavity between the outer flexible tube 8 and the inner sheath (shell 3-5) is filled and grease. The device works as follows. Through the driving rod 2 and the adapter 1, the rotation is transmitted from the drilling machine to the shells 3 and 4, which transmit the rotation to the drill bit (not shown). Due to the fact that shells 3 and 4 have the opposite direction of winding, and their ends are interconnected, the tapes interact, compensate for compressive forces, the internal cavity of the drill string is always open and provides free flow of flushing fluid. Simultaneously with the transmission of rotation, the driving rod 2 keeps the power shell from falling into the well under the action of gravity. The annular stops made on the adapter 1 and the stabilizer 7 keep the external pipe 8 of the drill string from falling as well. Under the action of friction force, the pipe 8 will also tend to start rotation, but the grooves of the stabilizer 7, which are brought into engagement with the guides 9 installed on the inner side of the casing 10, will not allow the stabilizer and the external pipe connected to it to rotate. At the same time, the grooves of the stabilizer can move along the longitudinal axis of the guides and allow the stabilizer to be lowered into the well as it deepens. The ring stops 12 and 13, made on the thickened hard sections of each column link, interact with each other, ensure the transfer of part of the tensile forces arising in the power jacket to the outer tube and improve the conditions of work first. The lifting of the drill string is carried out using existing traction units. The raised drill string is wound onto a drum of conventional dimensions. The axial pressure on the drill bit is created by any of the known axial pressure submersible systems (e.g., by separating high and low pressure fluid with a piston). The economic effect of using the proposed device for drilling wells is to increase the speed of drilling while maintaining continuity of the up and down operations. In addition, the device allows for the drilling of intensively bent multilateral wells with high productivity. In this case, the angle of inflection of the well bore may reach 90 ° or more. Claim 1. A device for drilling wells, including a flexible string of drill pipes, housed in a casing string and containing an inner power jacket, an outer flexible tube, an adapter and a stabilizer located in its upper part, characterized in that straight and inclined wells, the stabilizer and the external flexible pipe are connected to the connecting elements of the internal sheath with the possibility of relative rotation, the casing string has longitudinal apravl guides, and the outer surface stabilizer - s response grooves. 2. The device according to claim 1, characterized by the fact that the cavity between the outer flexible pipe and the inner sheath is filled with lubricant. 3. The device according to claim 1, characterized in that the inner sheath has two layers formed by Z-shaped ribbons