RU2786600C1 - Cable sub - Google Patents

Abstract

FIELD: oil production equipment.

SUBSTANCE: invention relates to equipment in oil production and is intended for lowering a downhole tool on a geophysical cable, and is included, in particular, in cable telesystems for navigation control from the surface. The cable sub contains a body, a sealing plug with a hole for a geophysical cable, a hollow bushing and an overlay. The body is made of two parts - upper and lower, interconnected by an internal thread. The lower part of the body of the sub is made with a ledge. The axis of the hollow sleeve is parallel to the axis of the sub, but offset from it. A tube is put on the upper end of the sleeve, into which a branch pipe is inserted coaxially with the body of the sub. In the lower part of the housing, a sealing plug and a hollow sleeve are placed parallel to each other. The axis of the sealing plug is parallel to the axis of the sub, but is offset from the axis of the sub body and coincides with the axis of the hollow sleeve. The sealing plug is made of two split elastic cuffs with a split metal ring installed between the cuffs. The ring and cuffs are made with a cut for the installation of a geophysical cable. The hollow sleeve is made with eccentric flanges at the top and bottom. The eccentric flanges are equipped with radial cutouts from the periphery to the center, providing placement of a geophysical cable in the cutouts. The upper eccentric flange is mounted on a hollow sleeve with the possibility of vertical axial movement and compression of the sealing plug, and the lower eccentric flange is rigidly fixed to the hollow sleeve. On the upper end of the hollow sleeve offset from the axis of the sleeve, but at the same time the axis of the tube coincides with the axis of the body of the sub, a tube is screwed by means of a threaded connection, with the possibility of creating a force by the lower end of the tube on the upper eccentric flange and then on the sealing plug. The tube outside opposite the geophysical cable is equipped with a conical bevel, and a branch pipe is inserted into the tube from above. The branch pipe is installed coaxially with the body of the sub and is equipped with an external thread on top, which ensures the fastening of the branch pipe to the upper part of the body. On the upper part of the body of the sub, there is an overlay for fastening the geophysical cable, while at the top in the lower part of the body of the sub, along the internal thread, a groove for the geophysical cable is made. The lower part of the sub is equipped with a stop at the bottom.

EFFECT: simplification of the design of the sub, increase of the reliability of its operation, reduction of the production cost and reduction of the assembly time.

1 cl, 5 dwg

Description

The invention relates to equipment in oil production and is intended for lowering a downhole tool on a geophysical cable, and is included, in particular, in cable telesystems for navigation control from the surface.

A cable sub is known (patent RU No. 66404, IPC E21V 17/02, publ. 09/10/2007), containing a threaded pipe with a conical cable entry gland, sealed by means of a pressure ring and a threaded bushing, the threaded bushing is elongated and contains a conical seat for an additional conical gland of the cable entry, sealed by means of an additional pressure ring and pressure nut, and holes are made in the sleeve itself in the area between the glands of the cable entry, through which the internal cavity of the sleeve communicates with pressure testing and drain valves and a pressure gauge.

Disadvantages of the translator:

- firstly, the complexity of the design due to the large number of components and parts (threaded pipe with a conical cable entry gland, pressure ring and nut, threaded bushing, etc.);

- secondly, limited functionality, since the sub does not meet the requirements of drilling horizontal and directional oil and gas wells using telesystems for navigation control from the surface of the drilling process and allows you to work only at the wellhead;

- thirdly, low reliability in operation, since the sub does not provide sealing of the cable at pressures above 7.0-8.0 MPa.

Known cable sub, mounted in the drill pipe string, which serves to seal the cable during transportation of the device suspended from it, lowered to the bottom of the well along the drill pipe string by the flow of drilling fluid supplied by the drilling pump (Krikshyunas V.P., Startsev A.O. Kit technical means SSK-46G. NTZ "Exploration and protection of mineral resources", "Nedra", M., 1991, No. 7, pp. 6-8). The sub contains a branch pipe in the form of a discharge chamber, a body, a sealing device and a side inlet nipple for connection to the mud pump manifold. The sealing device includes a package of rubber sealing cuffs, pressed by a spring, and serves to seal the cable when the device is hydraulically loaded at a pressure of 10-15 kgf / cm ² and supply no more than 2 l / s in shallow (up to 300 m) and small diameter (up to 46 mm) exploration wells drilled from the surface and from underground mine workings in deposits of coal and other minerals. The sealing device and the cable are placed in the central channel of the sub body, and the drilling fluid is supplied through the channel of the side supply nipple.

Disadvantages of the translator:

- firstly, the complexity of the design due to the large number of components and parts (package of rubber sealing cuffs, spring, sub, nipple, etc.);

- secondly, low reliability in operation, since the sub does not provide sealing of the cable in the process of drilling oil wells with downhole motors with simultaneous circulation of the drilling fluid at a working pressure of up to 5.0-7.0 MPa;

- thirdly, limited functionality, since the sub does not meet the requirements of drilling horizontal and directional oil and gas wells using telesystems for navigation control from the surface of the drilling process and allows you to work only at the wellhead.

A cable sub is known (patent RU No. 2267002, IPC E21V 17/02 publ. 12/27/2005), containing a threaded pipe with a thrust end, a body with straight and peripheral inclined channels, a bushing and an O-ring placed in a straight channel of the body, and the straight channel the body is made central, while it contains a cup with internal and external longitudinal grooves, the sleeve is installed with the possibility of interacting with the stop end of the threaded pipe and is made with longitudinal protrusions placed in the internal longitudinal grooves of the cup, the annular seal is made with a protrusion having a hole and a slot for entering the cable into the hole and placed in the peripheral inclined channel of the body, at the outlet of which there is a fuse in the form of a reinforcing element facing the straight channel, and an elastic element with a hole and a groove for accommodating and entering the cable, the sleeve has a restrictive ring installed by means of locking bolts n and its longitudinal protrusions, and the restrictive ring at the inlet of the drilling fluid flow has an end rounded inward with a radius of (0.1-0.2)d, where d is the diameter of the inner passage hole of the restrictive ring, and at the outlet it has a diffuser with a taper angle within 4 -10°, the upper end of the sleeve is made with an internal thread, the lower end of the threaded pipe is made with two cylindrical projections, one of which has a thrust end and is located in the interval of the internal thread of the sleeve, and the other has grooves for sealing rings placed on the outer surface.

Disadvantages of the translator:

- firstly, the complexity of the design, due to the large number of components and parts (threaded pipe with a thrust end, a body with straight and peripheral inclined channels, a bushing and an annular seal, a sleeve with internal and external longitudinal grooves, etc.);

- secondly, low reliability in operation, associated with a large number of parts dependent on each other during the assembly process, which can lead to loss of tightness of the sub during operation;

- thirdly, the high cost of manufacturing the product, due to the large number of technologically difficult to manufacture parts in the structure;

- fourthly, the long duration of assembly at the wellhead due to the large number of technologically complex units and parts.

The closest in technical essence and the achieved result is a cable sub containing a housing made of two parts - upper and lower, interconnected by an internal thread, and the lower part of the sub body is made with a ledge, a sealing plug with a hole for a geophysical cable, a hollow sleeve, the axis of which is parallel to the axis of the sub, but is located offset from it, a tube is put on the upper end of the sleeve, into which a branch pipe is inserted coaxially with the body of the sub, and an overlay (patent RU No. The geophysical cable runs from the outside to the inside of the sub. The lower part of the body of the sub is screwed onto the drill string, and a groove is made in the upper part of the body. the sub also contains two pipes, lock bushings, a clamping bushing and a cable holder, a sealing plug, and a nut. In the lower part of the sub body there is a sealing plug with lock bushings and with a hole for installing a hollow bushing, the axis of which is parallel to the sub axis, but located offset from it. The branch pipe installed coaxially with the sub body is fastened with a nut. On the top of the sub there is an overlay with two bolts for attaching the cable. The lower part of the body of the sub above the sealing plug also contains a clamping sleeve and a cable holder made in the form of a collet.

Disadvantages of the translator:

- firstly, the complexity of the design, due to the large number of components and parts (lock sleeves, clamping sleeve and cable holder, nut, etc.);

- secondly, low reliability in operation, associated with a large number of parts dependent on each other during the assembly process, which can lead to loss of tightness of the sub during operation;

- thirdly, the high cost of manufacturing the product, due to the large number of technologically difficult to manufacture parts in the structure;

- fourthly, the long duration of assembly at the wellhead due to the large number of technologically complex units and parts.

The technical objectives of the invention are to simplify the design of the cable sub, increase the reliability of its operation, as well as reduce the cost of manufacturing the cable sub, reduce the duration of its assembly at the wellhead and expand the arsenal of technical means for lowering the geophysical cable.

Technical problems are solved by a cable sub containing a body made of two parts - upper and lower, interconnected by an internal thread, and the lower part of the body of the sub is made with a ledge, a sealing plug with a hole for a geophysical cable, a hollow sleeve, the axis of which is parallel to the axis of the sub, but is located offset from it, a tube is put on the upper end of the sleeve, into which a branch pipe is inserted coaxially with the body of the sub, and an overlay.

What is new is that in the lower part of the body the sealing plug and the hollow sleeve are placed parallel to each other, while the axis of the sealing plug is parallel to the axis of the sub, but is located offset from the axis of the sub body and coincides with the axis of the hollow sleeve, and the sealing plug is made of two split elastic cuffs with a split metal ring installed between the cuffs; in this case, the upper eccentric flange is mounted on a hollow sleeve with the possibility of vertical axial movement and compression of the sealing plug, and the lower eccentric flange is rigidly fixed to the hollow sleeve, on the upper end of the hollow sleeve offset from the axis of the sleeve, but the axis of the tube coincides with a tube is screwed on by the axis of the body of the sub, with the help of a threaded connection, with the possibility of creating force by the lower end of the tube on the upper eccentric flange and then on the sealing plug, and the tube on the outside opposite the geophysical cable is equipped with a conical bevel, and a pipe is inserted into the pipe from above, and the pipe is installed coaxially with the body sub and is equipped on top with an external thread that secures the branch pipe to the upper part of the body, and on the upper part of the sub body there is a pad for attaching a geophysical cable, while at the top in the lower part of the sub body along the internal thread a groove is made for the geophysical cable, and the lower part of the sub is from below equipped with a stop.

In FIG. 1 schematically shows a cable sub.

In FIG. 2 shows section A-A of the cable sub.

In FIG. 3 shows the B-B section of the cable sub.

In FIG. 4 shows the B-B section of the cable sub.

In FIG. 5 shows the G-D section of the cable sub.

The cable sub contains a housing 1 (see Fig. 1), made of two parts - top 2 (see Fig. 1, 5) and bottom 3 (see Fig. 1-5). In the lower part 3 of the housing 1 parallel to each other are placed: a sealing plug 4 (Fig. 1) and a hollow sleeve 5 (see Fig. 1, 2, 3).

The axis of the sealing plug 4 is parallel to the axis of the body of the sub, but is offset from it. The sealing plug 4 (see Fig. 1, 2) is made in the form of two split elastic cuffs 6' (see Fig. 1, 2) and 6'' (see Fig. 1) with a split metal ring 7 installed between them ( see Fig. 1, 3). Elastic cuffs are made of rubber O-rings according to GOST 9833-73. Split elastic cuffs 6' and 6'' and split metal ring 7 have the ability to install a geophysical cable 8 (see Fig. 1-5) through the cuts. The cuts of the elastic cuffs 6' and 6'' are offset relative to the cut of the metal ring 7 by 90° (see Fig. 2, 3).

The hollow sleeve 5 is equipped with eccentric flanges 9 (see Fig. 1) and 10, respectively, from below and from above. Eccentric flanges 9 and 10 are equipped with corresponding radial cutouts 11 and 12 from the periphery to the center to accommodate the geophysical cable 8.

The upper eccentric flange 9 is mounted on the hollow sleeve 5 with the possibility of vertical axial movement and compression of the elastic cuffs 6'' and 6', and the lower eccentric flange 10 is fixed to the hollow sleeve 5 rigidly, for example by welding.

A tube 14 is screwed onto the upper end of the hollow sleeve 5 offset from it by means of a threaded connection 13 (see Fig. 1) (see Fig. 1, 4). The axis of the tube 14 coincides with the axis of the body of the sub. Thanks to the threaded connection 13, the tube 14 with its lower end acts on the upper eccentric flange 9, which transfers the compression force to the elastic cuffs.

Tube 14 on the outside opposite the geophysical cable 8 is made with a conical bevel 15 (see Fig. 1, 4). From above, a branch pipe 16 is inserted into the tube 14 (see Fig. 1, 5). The branch pipe 16 is installed coaxially with the body 1 of the sub and is equipped on top with an external thread 17 (see Fig. 1) with which the pipe 16 is attached to the upper part 2 of the body 1. The upper 2 and lower 3 parts of the body 1 of the sub are interconnected by an internal thread 18, on the upper part 2 of the body of the sub has a pad (blot) 19 (see Fig. 1) for attaching the geophysical cable 8.

From above, in the lower part 3 of the body 1 of the sub, along the internal thread 18 to a depth and width equal to the diameter of the cable, a groove 20 is made (see Fig. 1, 5) for a geophysical cable 8. The lower part 3 of the body of the sub from below is equipped with a stop 21 (see Fig. . one).

The cable adapter works as follows.

On the thread 22 (see Fig. 1) of the lower part 3 of the housing 1 of the sub, screw the pipe of the drill string (not shown in Fig. 1-5).

Then in the drill string through the lower part 3 (see Fig. 1) of the body 1 of the sub is lowered into the well on the geophysical cable 8 downhole tool (Fig. 1-5 not shown). On the geophysical cable 8 (see Fig. 1-3) above the upper edge of the lower part 3 of the body 1, the following parts are sequentially installed:

- a hollow sleeve 5, rigidly connected to the lower eccentric flange 10, into which the geophysical cable 8 is inserted through the cutout 12 of the eccentric sleeve 10;

- from the upper end of the hollow sleeve 5 from top to bottom, the following are inserted in sequence: the first split elastic ring 6 ', the split metal ring 7, the second split elastic ring 6'', and the upper eccentric flange 9, while the geophysical cable 8 is inserted through the cuts of the first split elastic ring 6', a split metal ring 7, a second split elastic ring 6'' and through the cutout 11 of the upper eccentric flange 9 of the sleeve.

The assembled structure is lowered into the lower part 3 of the housing 1 of the sub until it stops 21 (see Fig. 1).

Next, the tube 14 is lowered into the lower part 3 of the body 1 of the sub, after installing the pre-sealing rings 23 (see Fig. 1), and it is screwed with the help of thread 13 onto the upper end of the hollow sleeve 5. The tube 14 is turned, while the lower end of the tube 14 due to the inversion of the thread 13, it creates an axial force from top to bottom on the upper eccentric flange 9, which shifts down and seals the geophysical cable 8 with the help of the first split elastic ring 6' and the second split elastic ring 6'', which are compressed in the axial direction, and in expand in the radial direction, sealing the geophysical cable 8, while the cuts of the elastic cuffs 6' and 6'' are shifted relative to the cut of the metal ring 7 and the lower end by 90°, which ensures the tightness of the sealing plug 4. The geophysical cable 8 is installed from the side of the conical bevel 15 of the tube ( see Fig. 4).

In the hole of the upper part 2 of the body 1 (see Fig. 1) of the sub, first insert the branch pipe 16, which is then screwed into the hole of the upper part 2 of the body 1 by thread 17, while the branch pipe 16 is hermetically inserted into the tube 14 thanks to the sealing rings 23. In the groove 20 (see Fig. 5), made along the internal thread 18 from above in the lower part 3 of the housing 1 of the sub, a geophysical cable 8 is laid. 1 sub so that the tapered bevel 15 is opposite the groove 20.

Further, the upper 2 and lower 3 parts of the body 1 of the sub are interconnected by an internal thread 18, while the geophysical cable 8 remains motionless. From the top outside, in the upper part 2 of the body 1 of the sub, the geophysical cable 8 is fixed with the help of an overlay (blot) 19.

The cable sub prepared in this way is ready for operation. The disassembly of the cable sub is carried out in the reverse order.

The cable sub in comparison with the prototype has a simple design, since two pipes, locking and clamping sleeves, and nuts are excluded from it.

The cable sub has a high reliability in operation, which is associated both with the simplification of the design and with a decrease in the number of parts that are dependent on each other, representing the design of the device, i.e. the simpler the design, the more reliable the device in operation. In addition, the sealing plug is made in the form of two split elastic cuffs with a split metal ring installed between them, which increases the reliability of sealing the geophysical cable. All this completely eliminates the loss of tightness of the sub during operation.

The cost of manufacturing a cable sub is halved, which is due to a decrease in the number of technologically difficult to manufacture parts in the structure.

The assembly time at the wellhead is reduced by 10-15 minutes due to the simplification of the design and the reduction in the number of technologically complex units and parts.

The cable adapter has:

- simple design;

- high reliability in work;

- low manufacturing cost;

- reduced assembly time at the wellhead.

Claims (1)

A cable sub containing a body made of two parts - upper and lower, interconnected by an internal thread, and the lower part of the body of the sub is made with a protrusion, a sealing plug with a hole for a geophysical cable, a hollow sleeve, the axis of which is parallel to the axis of the sub, but is located with offset from it, a tube is put on the upper end of the sleeve, into which a branch pipe is inserted coaxially with the body of the sub, and an overlay, characterized in that in the lower part of the body the sealing plug and the hollow sleeve are placed parallel to each other, while the axis of the sealing plug is parallel to the axis of the sub, but located offset from the axis of the body of the sub and coincides with the axis of the hollow sleeve, and the sealing plug is made of two split elastic cuffs with a split metal ring installed between the cuffs, the ring and cuffs are made with a cut for the installation of a geophysical cable, while the hollow sleeve is made from below and from above with eccentric f flanges, eccentric flanges are equipped with radial cutouts from the periphery to the center, providing placement of a geophysical cable in the cutouts, while the upper eccentric flange is mounted on a hollow sleeve with the possibility of vertical axial movement and compression of the sealing plug, and the lower eccentric flange is rigidly fixed to the hollow sleeve, on the upper the end of the hollow sleeve is offset from the axis of the sleeve, but the axis of the tube coincides with the axis of the body of the sub, with the help of a threaded connection, the tube is screwed, with the possibility of creating a force by the lower end of the tube on the upper eccentric flange and then on the sealing plug, and the tube is outside opposite the geophysical cable equipped with a conical bevel, and a branch pipe is inserted into the tube from above, moreover, the branch pipe is installed coaxially with the body of the sub and is equipped with an external thread at the top, which ensures the fastening of the branch pipe to the upper part of the body, and on the upper part of the body of the sub there is an overlay for fixing geophysical th cable, while at the top in the lower part of the body of the sub along the internal thread there is a groove for the geophysical cable, and the lower part of the body of the sub is equipped with a stop from below.

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