RU2229583C1 - Section of current lead to electrodrill - Google Patents

Abstract

FIELD: boring technology. SUBSTANCE: section has boring pipe equipped with nipple and circular cam box connector, and cable section having a portion of twin-core cable ending with conical socket fixed on supports in circular cam and with rod of detachable contact connection. Contact connection of cable section is made in form of coaxial connector formed by concentrically mounted in isolation bushings hollow cylindrical conductors, which on one side are connected to cable cores, and on the other side are terminated with contact nosepieces. On the input of connector near the base of conical connection of the socket with the rod, pliers clamping device is mounted. EFFECT: increased reliability of operation of cable sections. 3 cl, 4 dwg

Description

The invention relates to electrical drilling equipment, namely, to the current supply of electrical drills designed for drilling oil and gas wells.

Known current leads to the electric drill according to the two-wire circuit - a pipe consisting of sections including drill pipes equipped with a nipple and a pipe lock coupling, as well as cable sections containing a segment of a two-core cable ending in a conical socket and a detachable contact connection rod fixed to the supports in the pipe lock [1].

The main disadvantage of the known sections of the current supply is the low reliability due to the frequent failure of the cable sections.

The most common types of damage to cable sections are (Arkhangelsky NK Improving the power supply for electric drills. In the book "Electric Drilling". - M., 1964);

- breakdown of insulation on the surface of the connector of the cable connections between the contact rings and the breakage of the copper conductive busbars connecting the cable conductors to the contact lugs (65%);

- breakdown of insulation in places of splicing of cable conductors with detachable contact joints (15%);

- breakdown of cable core insulation (5%);

- external mechanical damage to contact joints (15%). The causes of these damage are structural flaws in the used cable sections, which include:

- unreliable protection of contact joints with a conical rubber seal against the penetration of flushing fluid;

- rigid fastening of the supports of the cable section in the pipe lock, resulting in the presence of an eccentricity between the socket and the pin of the contact connection in the current-carrying busbars when screwing the pipes, significant mechanical stresses arise that contribute to the destruction of the busbars under the action of dynamic loads excited during drilling;

- the use of rectangular busbars in contact joints, which leads to the creation of an inhomogeneous electric field in the connector, facilitating the breakdown of insulation;

- a sharp change in the cross section of the flushing channel in the drill pipes at the attachment points of the cable sections, as a result of which conditions are created for cavitation and external damage under its influence of the contact joint;

- a relatively large cross section of the cable section, in connection with which the loss of pressure of flushing fluid in the drill pipe reaches 50%.

The closest of the known sections of the current supply to the proposed one is the coupling of the cable section of the current supply of the electric drill [2].

In this invention, to avoid breakdown in the contact connection, the cable section socket is equipped with a chamber filled with a liquid dielectric, which, according to the authors, should be forced out of the chamber during drilling when it is compressed by external hydrostatic pressure and thereby prevent the penetration of washing liquid into the connector. However, the back pressure created inside such a coupling cannot be greater than the external pressure of the washing liquid due to pressure losses on the deformation of the shell of the chamber and therefore penetration of the washing liquid into the connector is not ruled out. In addition, in this connection, as in other known cable sections, there is no centering of the socket with the rod when connecting the pipes, as a result of which a one-sided gap may occur in the conical connection of the connector, which will also facilitate the penetration of fluid into the connector.

The objective of the invention is to remedy the above disadvantages, i.e. improving the reliability of cable sections.

This problem is solved in that the section of the current supply to the electric drill includes a drill pipe equipped with a nipple and a pipe lock coupling, as well as a cable section containing a segment of a two-core cable ending with a conical socket and a detachable contact connection rod fixed to the supports in the pipe lock, while the connector is detachable the cable section is made in the form of a coaxial connector formed by hollow cylindrical conductors concentrically mounted in insulating sleeves, which are Second side connected to the conductors of the cable, and the other end in contact lugs, wherein the inlet taper joint at the base of the rod connector socket set gripper device.

The supports of the cable section are mounted on movable rings that can be moved in the radial and angular directions, located in the grooves of the clutch and nipple of the lock, and the cable section is made on a piece of coaxial cable.

A comparison of the claimed technical solutions with prototypes allows us to establish their compliance with the criterion of "novelty." In the study of other technical solutions in the art, the features that distinguish this invention from prototypes were not identified and therefore they provide the claimed technical solution according to the criterion of "significant differences".

In Fig.1 shows a General view of the section of the current supply to the electric drill assembly with the drill pipe and cable section, Fig.2 is a view of the end section of the current supply, and in Fig.3 and Fig.4 are sections of the contact rod and socket along the planes A- A and BB.

The current supply section (Fig. 1 and Fig. 2) includes a piece of coaxial cable 1, a two-pin terminal 2 with a support 3, forming a coaxial connector with a coaxial two-pin socket 4 with a support 5. The supports 3 and 5 of the cable section are screwed to the rings 6 movable in the radial and angular directions, located in the grooves of the nipple 7 and the sleeve 8 of the pipe lock of the drill pipe 9.

The contact rod 2 (Fig. 3) contains two hollow cylindrical conductors 11 and 12. concentrically mounted and isolated between them by the sleeve 10. In this case, the inner core 13 of the coaxial cable 1 passes through the conductor 11, which is soldered to the end of the tip 14 at the outlet of the conductor 11. The conductor 12 is welded on one side to the outer conductor 15 (cable sheath) and, on the other hand, terminated by a tip 16. On the sleeve 10, a cone 17 is made between the tips 14 and 16, and the conical recess 18 jointed with the end end is on the other end. abelnoy isolation. An insulating sleeve 19 is fixed on the cylindrical conductor 12, on which a metal sleeve 20 is installed, ending on one side with a support 3, and on the other, a conical sleeve 21 of the collet clamp, preloaded by the spring 31, is freely mounted. Contact socket 4 (Fig. 2), also , like the rod 2, contains two cylindrical conductors 23 and 24 concentrically mounted and insulated between each other by a sleeve 22 (Fig. 4), ending with contact tips 25 and 26. An insulating sleeve 27 is pressed onto the conductor 24, onto which a clip 28 is fitted illogical clip 20, but in contrast to it has at the end a split collet 29 located above the base of the conical part of the sleeve 27.

The device operates as follows.

When making up drill pipes using the sleeve 8 and the nipple 7, the rod 2 of one cable section enters the socket 4 of the other section, while the centering of the socket and the rod occurs due to the displacement of the movable rings 6 and the connection of the contacts. At the end of make-up, the tapered sleeve 21 presses the collet 29, which creates a reliable seal of the connector. In addition, due to the clamp collet 29 and the installation of the cable section on the movable rings 6, the rod 2 at the time of connection does not rotate in the socket, which eliminates the appearance of torsional forces in the contact connection.

The rod 2 and socket 4 are disconnected from the cable during repairs by stripping the insulation and disconnecting the cable conductors from the connector conductors in the places indicated at 30.

Sources of information

1. USSR author's certificate No. 202022, E 21 17/02, 1967.

2. Fomenko F.N. Drilling wells with an electric drill. - M .: Nedra, 1974, p. 116, Fig. 52.

Claims (3)

1. The section of the current supply to the electric drill, including a drill pipe provided with a nipple and a pipe lock coupling, as well as a cable section containing a segment of a two-core cable ending with a conical socket and a detachable contact connection rod fixed to the supports in the pipe lock, characterized in that the detachable contact connection the cable section is made in the form of a coaxial connector formed by hollow cylindrical conductors concentrically mounted in insulating sleeves, which are connected on one side cheny to the conductors of the cable, and the other end in contact lugs, wherein the inlet in the junction cone base connector socket set with the rod gripper apparatus. 2. Section according to claim 1, characterized in that the supports are mounted on movable rings that can be moved in radial and angular directions, located in the grooves of the clutch and lock nipple. 3. The section according to claim 1, characterized in that the cable section is made on a piece of coaxial cable.

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