RU2482257C1 - Disconnector - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: disconnector includes a hollow housing with a bore, a reducer with holes, a load with an annular bore and a restrictor on lower end in an axial channel, fasteners in the form of balls, which are installed in the reducer's holes with possibility of interaction with the load and the hollow housing. The reducer includes a crossover, in which a nut is installed, a spring-loaded annular piston with a seat under the ball valve and a collet grip with petals passed through the nut to the axial channel of the reducer. The load is equipped with an annular bore with a cylindrical projection on upper end and a through axial channel; at that, on outer surface of the load there made are annular grooves and installed are seals, above and below fastener location place, and the reducer is installed in the axial channel of the hollow housing with possibility of axial movement and is equipped with a stop nut and a seal.

EFFECT: possibility of emergency-free lowering of downhole equipment, possibility of pressure supply of working fluid to the device, with transfer to the well cavity, possibility of controlled detachment of the disconnector from the downhole equipment.

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Description

The invention relates to the oil and gas industry and is intended for the installation of various equipment in the well.

A device for installing equipment in a well is known (see Zaitsev Yu.V. et al. “Equipment for Preventing Open Fountains of Oil and Gas Wells.” M., “Nedra”, 1973, p. 165).

The device consists of a nipple, a case with windows, a latch for placement in a groove made in the nipple, a spring-loaded sleeve concentrically placed in the case. Disadvantages - the installation and removal of instruments and equipment is carried out using a special landing tool, lowered on the rope, which can cause complications associated with its breakage and loss of recoverable equipment.

A device is known for installing downhole equipment (see II AS No. 607956 Mcl. E21B 43/00, publ. 25.05.78, Bull. No. 19). The device consists of a housing, the windows of which are latched. In the axial channel of the housing is a spring-loaded sleeve with a piston. On the inner surface of the housing channels are made. The housing is equipped with clamps. The spring loaded sleeve is equipped with clamps and grooves. The device is installed in a nipple, with annular grooves.

The housing is threaded to connect the lock with the installed equipment.

The release of equipment from the device creates excess pressure over the device, perceived by the cross-sectional area of the sleeve.

Nevertheless, this is quite problematic, since the axial channel is open for the passage of the working fluid and it is not possible to raise the pressure. When installing the ball on the end face of the sleeve, it is necessary to discharge it from the wellhead and supply excess pressure. Thereby, the housing is separated from the latch.

Lifting equipment from the well - by creating a fluid flow by reverse circulation and trapping the device at the wellhead with a special catcher.

The disadvantage is the need to create fluid circulation through the use of a pumping unit. When lifting the device up, you need to spend a lot of time.

A device for connecting and disconnecting a pipe string with downhole equipment (see AS No. 609869, Mcl. E21B 33/12, publ. 05.06.78, Bull. No. 21). The device consists of a housing with stops between which latches are placed. In the axial channel there is a nipple with a protrusion connected with a coupling concentrically placed relative to the nipple, with the formation of an annular channel in which the pusher is placed, with the possibility of interaction with latches. A stepped annular piston with a spring is installed above the pusher.

The operation of the device.

The device is connected to the downhole equipment by introducing a nipple into the axial channel of the body until it contacts the stop.

This can be done both at the wellhead and in the case of equipment at a depth.

The disadvantages of the design of the device include:

- the possibility of unauthorized disconnection of the device from the equipment, in the case of the supply of the working fluid under the reservoir, for example in the case of its processing or for the hydraulic landing of the packer;

- during pump operation of wells, when the hydrostatic pressure in the axial channel of the pipes of the elevator string exceeds the hydrostatic pressure of the column of formation fluid in the annulus;

- the design feature of the device is the presence of a fixing unit as part of the downhole equipment, which can be in the well for a long enough time, which can lead to the ingress of mechanical impurities into the gaps, which can serve as an obstacle to the movement of the latches in the gaps when the device is reattached to the equipment. These operating conditions affect the reliability and performance of the sealing element, and therefore the reliability of the device.

A device for releasing pipes (III) trapped in a well is known (see AS USSR No. 1,574.792 Ml. EV21B/10/107, publ. 10.12.87, Bull. No. 24), adopted as a prototype.

The device consists of a rod, in the form of a load installed in the cavity of the body of the cargo, with a limiter in the lower part, for interaction in the working position with the lower end of the pipe of the disconnection unit. The rod is equipped with an annular groove made with a conical section in the upper part.

The disconnection unit has balls placed in the initial position in the annular groove of the body, with the possibility of interaction with the conical section of the rod. The pipe is threaded in the upper part, for communication with the pipe string.

When the pipe string is pulled, the balls interact with the conical chamfer of the body groove and transmit radial force through the balls to the conical section of the rod, which, when the axial force is calculated, leads to the lifting-moving of the load upward in the axial channel of the body, with the balls falling into the annular groove of the rod.

The device can be configured for different axial forces at which disconnection can occur due to the selection of the rod weight and a change in the angle of inclination of the conical section.

When the nozzle moves downward, with the housing stationary, the rod together with the balls can move down to the stop by the stop in the bottom, which can lead to the rod moving relative to the balls and the conical section coming out of interaction with them. Thus, unauthorized separation of the device from the pipe to be removed can occur. Such a situation may arise, for example, in case of accidental interaction of the casing with the casing wall.

The technical result that can be obtained by using the invention is as follows:

- the possibility of trouble-free descent of downhole equipment, when communicating via a disconnector with a pipe string;

- the ability to supply a working fluid under pressure to a device, with transmission to a well cavity, for example, for planting a hydraulic packer or treating a reservoir;

- the possibility of a controlled disconnection of the disconnector from the downhole equipment, by supplying a ball valve to the seat and creating a differential at the last, capture and output of the load from the interaction with the clamps.

The technical result is achieved in that the disconnector comprises a hollow body with a bore, in the axial channel of which an adapter is installed with holes and a load in the axial channel. The load is equipped with an annular groove and a stopper on the lower ring and is mounted on clamps in the form of balls located in the holes of the adapter, when the latter interact with the hollow body.

The adapter contains an adapter, in which a nut is installed, a spring-loaded annular piston with a seat under the ball valve and a collet with petals passed through the nut into the axial channel of the adapter. The load is equipped with an annular groove with a cylindrical protrusion on the upper ring and a through axial channel.

On the outer surface of the load, annular grooves are made and gaskets are installed with the location above and below the location of the latches. The adapter is installed in the axial channel of the hollow body, with the possibility of axial movement, and is equipped with a thrust nut and seal.

The design of the device for connecting and disconnecting with downhole equipment is illustrated by the following drawings, where:

- figure 1 - sectional design of the device in the position of connection with the downhole equipment;

- figure 2 - the design of the device in the position of the beginning of disconnection from the downhole equipment.

- figure 3 - the design of the device in the position of exit from the interaction with downhole equipment.

The device consists of an adapter 1 equipped with a thrust nut 2 in the lower part. A load 4 is mounted in the axial channel 3 of the adapter 1 in the form of a cylinder, at the lower end of which an annular groove 5 is made, with a conical section 6 overlapped by a stop 7. The upper end of the load 4 is made in the form of a cylindrical protrusion 8 with an annular groove 9. A number of holes 10 are made in the adapter 1, in which balls 11 are inserted, which interact with the inner surface of the hollow body 12, at the place where the annular groove 13 is made, and a conical section 6 in the annular groove 5 of the load 4.

The upper end of the adapter 1 is equipped with a sub 14, in the axial channel 15 of which a nut 16 is installed, and a spring-loaded ring piston 17, equipped with a seating seat 18 and a collet gripper 19 at the lower end, the petals 20 of which are passed through the axial channel of the nut 16. The annular gap between the load 4 and the adapter 1 is blocked by seals 21 and 22. The gap between the adapter 1 and the hollow body 13 is blocked by a seal 23. In the body of the load 4 there is an axial channel 24 for connecting the cavity of the pipe pipe string with the axial channel of the equipment being pulled apart body into the well.

The operation of the device.

The device is connected to downhole equipment, for example, to a packer, with which it is connected through the housing 12 and descends into the well by pipes. When equipping a well with packers with a hydraulic method of planting, a flow of pressurized working fluid for planting is possible through the device.

If it is necessary to disconnect the pipe string from the packer, a ball with a seat on the saddle 18 is fed into its axial channel (see figure 3). When applying excess pressure of the working fluid to the axial channel 15 of the pipe string, the latter is communicated to the spring-loaded annular piston 17, with its movement downward in the direction of the load 4. The collet 19 passes by the cylindrical protrusion 8, with the location of the petal heads 19 in the annular groove 9. After the pressure relief, by the force of the compressed spring, the annular piston 17 moves up into the sub 14, together with the load 4, which moves relative to the balls 11, which leads to their location in the annular groove 5. Tension of the column tr b adapter 1 is moved upward relative to the housing 12 that leads to precipitation of the balls 11 from the holes 10 and they are located on the surface of the limiter 7. Thus, the detachment of the pipe string occurs from the hollow body 12 associated with a packer and a lifting device to the surface.

Claims (1)

A disconnector comprising a hollow body with a bore, an adapter with holes, a load with an annular groove and a stopper at the lower end in the axial channel, spacers in the form of balls installed in the holes of the adapter, with the possibility of interaction with the load and the hollow body, characterized in that the adapter contains sub, in which the nut is installed, a spring-loaded ring piston with a seat under the ball valve and a collet gripper with petals passed through the nut into the axial channel of the adapter, the load is equipped with an annular groove with an cylindrical protrusion at the upper end and a through axial channel, moreover, annular grooves are made on the outer surface of the cargo and seals are installed, above and below the location of the clamps, and the adapter is installed in the axial channel of the hollow body, with the possibility of axial movement and equipped with a thrust nut and seal.

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