RU2555846C1 - Hydraulic packer - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: intended for disconnection of the well casing string between the submerged pump and equipment for produced fluid separation from mechanical admixtures, and can be also used during development and operation of the oil and gas wells. The hydraulic packer contains stock with thread ends, installed on stock sealing assembly containing stop, movable sleeve and installed between them sealing element, and hydraulic drive containing a hydraulic cylinder and valves system. At that end part of the spring-loaded piston of the hydraulic cylinder is located in the internal boring of the movable sleeve. On the hydraulic cylinder lid a ball check valve and differential valve are installed, they are hydraulically connected with each other by the common chamber connected with output of the submerged pump. At that the differential valve is provided with radial channel, that during shutdown of the submerged pump connects the above piston cavity of the hydraulic cylinder with annulus.

EFFECT: improved design of the hydraulic packer, improved comfort o maintenance.

2 cl, 4 dwg

Description

The invention relates to the oil industry. It is designed to isolate the well casing between the submersible pump and equipment for separating the produced fluid from mechanical impurities, and can also be used in the process of development and operation of oil and gas wells.

Known mechanical packer according to patent RU No. 2139408 for tight shutoff of a wellbore, comprising a rod with a system of shaped grooves made on it, a sealing unit with sealing elements abutting against the rod, and an anchor unit with spring-loaded slips actuated by a movable cone, mechanical the packer is brought from the transport position to the working position by lifting it by 0.3-0.6 meters in the casing and subsequent descent. The disadvantages of the known device are the low reliability of the anchor, in particular curly grooves, due to wear from exposure to mechanical particles of the rock.

Known mechanical packer for sealing the overlap of the wellbore according to patent RU No. 2092675, comprising a rod, a sealing unit with a sealing element, a stop of the sealing element and a movable cone, as well as an anchor unit with sliding slips. When installed in the working position, the anchor unit is set in motion from the hydraulic actuator.

The described types of packers have a common drawback - the need for anchor devices. The use of packers with anchor devices for sealing the wellbore with equipment for controlling mechanical impurities (separators, filters) is limited, because It requires mandatory labor-intensive and expensive preparation of the wellbore involving equipment for overhaul.

The prototype of the present invention can be considered the packer according to patent RU No. 43582, including self-sealing cuffs with a hydraulic unpacking system fixed to the pipe string by means of internal pipes. Despite the absence of an anchor device, the packer is structurally complex and requires a number of technological manipulations for installation in the working position, including the creation of flushing fluid pressure in the wellbore using special ground equipment (mobile pumping units).

Thus, the task to which the claimed invention is directed is to improve the design of the hydraulic packer, the technical result of which is to reduce the cost of installing the packer, increase the ease of maintenance, including due to the absence of an anchor device, and also eliminating the need to attract additional ground equipment .

The specified technical result is achieved in that in a hydraulic packer having a rod with threaded ends, a sealing unit mounted on the rod including a stop, a movable cage and a sealing element located between them, and a hydraulic actuator consisting of a hydraulic cylinder with a spring-loaded movable piston, the lower end of which is located in the inner bore of the movable clip.

The novelty of the invention is that on the cover of the hydraulic cylinder there is a ball check valve and a differential valve hydraulically interconnected by a common chamber communicating with the output of the submersible pump, while the differential valve is equipped with a radial channel that, when the submersible pump stops, connects the over-piston cavity of the hydraulic cylinder with the annulus .

A special case of the invention is provided.

The outer piston of the hydraulic cylinder is sealed with V-cuffs.

The implementation of the piston of the hydraulic cylinder, which is sealed with V-cuffs on the outer diameter, eliminates the possibility of jamming in the piston-cylinder housing coupling due to an increase in the tolerance area for the outer diameter.

The presence of a hydraulic actuator provides increased efficiency of the hydraulic packer, while the pressure in the hydraulic actuator is created during the operation of a submersible pump transmitted by a high pressure pipe through a special head.

The possibility of carrying out the invention, characterized by the above set of features, is confirmed by the description of the hydraulic packer made in accordance with the present invention. The description is accompanied by the following graphic materials:

Figure 1 - General view of the hydraulic packer;

Figure 2 - packer unit hydraulic packer in the transport position;

Figure 3 - hydraulic packer A;

Figure 4 - hydraulic packer in operating position.

The hydraulic packer (Figure 1) includes a packer assembly 1 and a hydraulic packer A with a pressure supply unit 2.

The packer assembly 1 (FIG. 2) includes a stem 3 with threaded ends 4 and 5, on which a coupling 6 and a sub 7 are mounted respectively. A sealing assembly comprising a stop 8, a movable clip 9 and a sealing element 10 located between them is installed on the rod 3. The sealing element 10 is made of an elastic material, such as rubber.

The hydraulic drive of the packer A (Fig. 3) includes a hydraulic cylinder 11, which is mounted on the rod 3 and is fixed from longitudinal movement with the help of the spacer sleeve 10 and the locking ring 13.

The hydraulic cylinder 11 includes a housing 14, a cover 15, a base 16, and a spring-loaded piston 17. A ball check valve 18 and a differential valve 19 are mounted on the cover 15 and are hydraulically interconnected by a common chamber 20 communicating with the high pressure pipe 28 with the outlet of the submersible pump (see Fig. .one).

The ball check valve 18 is pressed by the cover 21 and the spacer sleeve 22 with holes extending into the common chamber 20. In the cover 21, a fitting 23 is mounted on the thread for connecting to the high pressure pipe 28.

The distance between the ends of the cover 24 and the differential valve 19 must be larger than the stroke length of the latter. If there is pressure in the common chamber 20, the differential valve 19 closes the radial channel 25, which connects the pressurized over-piston cavity B with the annulus of the well.

The node for supplying pressure to the hydraulic actuator (figure 1) includes a special head 26, fitting 27, an oil-filled high pressure pipe 28 with nipples 29.

The hydraulic packer is used as follows.

In the transport position, the spring-loaded piston 17 of the hydraulic cylinder 11 is in its highest position.

A submersible pump unit with a packer descends to a predetermined mark in the well. The output of the submersible pump through a special head 26 with a high pressure pipe 28 is connected to the ball check valve 18 of the hydraulic cylinder 11. The submersible unit is launched into operation, creating the necessary working pressure, which is supplied through the high pressure pipe 28 to the common chamber 20 (Fig. 3), the ball check valve 18 opens, passing the working fluid into the over-piston cavity of the hydraulic cylinder B, under the action of the working pressure, the spring-loaded piston 17 moves to the lower position, compressing the spring and resting against its lower end in odvizhnuyu holder 9, which transmits an axial force on the sealing member 10 (Figure 2), it deforms to seal the annular space.

At the time the packer is put into operating position, the differential valve (Fig. 3), also under the influence of the pressure of the submersible pump, is located in the lowermost position due to the difference in the area of the differential piston and blocks the radial channel 25 connecting the over-piston cavity B of the hydraulic cylinder 11 with the annular space.

The transfer of the packer into the transport position is done by stopping the submersible pump (Fig. 4). In this case, the pressure in the common chamber 20 is released and under the influence of the working pressure in the supra-piston cavity B of the hydraulic cylinder 11, the ball check valve 18 closes, and the differential valve 19 moves to its highest position, opening the radial channel 25, which connects the supra-piston cavity B of the hydraulic cylinder 11 with the annulus (figure 3). The pressure in the above-piston cavity B of the hydraulic cylinder 11 is aligned with the pressure in the annulus, as a result of which the spring-loaded piston 17 moves to its original position. The sealing element 8 takes its initial dimensions and the packer is brought into transport position.

Sources of information taken into account when preparing the application:

1. RF patent for the invention No. 2139408, (class E21B 33/12), 1998.

2. RF patent for the invention No. 2092675 (class E21B 33/128), 1995.

3. RF patent for utility model No. 43582 (class E21B 33/129), 2004.

Claims (2)

1. A hydraulic packer having a rod with threaded ends, a sealing assembly mounted on the rod, including a stop, a movable holder and a sealing element located between them, and a hydraulic actuator consisting of a hydraulic cylinder with a spring-loaded movable piston, the lower end of which is located in the inner bore of the movable holder, characterized in that on the cover of the hydraulic cylinder there is a ball check valve and a differential valve hydraulically interconnected by a common chamber communicating with the output of the submersible wasp, wherein the differential valve is provided with a radial channel, which when stopping the submersible pump connects with the cylinder chamber above the piston annulus. 2. The packer according to claim 1, characterized in that the piston of the hydraulic cylinder on the outer diameter is sealed with V-cuffs.

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