RU2539504C1 - Device for injection of fluid into bed - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: device includes a hollow case with a discharge channel and protrusion from below, a barrel placed coaxially inside the hollow case and designed for axial movement, a replaceable jet nozzle and a valve passing fluid inside-out. The hollow case is equipped with inner circular breakdown, the barrel is equipped with an outer circular bore with a locking ring installed in it; the barrel is fixed in regard to the hollow case by a shear tie. On the top the barrel is equipped with a plug catching baffle for a ball thrown to the flow string. Opposite the discharge channel in the hollow case there is an adjustable valve mounted eccentrically; the valve consists of a spring-actuated piston with a rod and an adjusting nut. Below the piston in the valve there is a hydraulic chamber, which can be interconnected to inner space of the hollow case, at that under excess pressure in the hydraulic chamber the piston can be moved axially upwards thus interconnecting the hydraulic chamber to the bed through an outlet opening of the valve, which is equipped with a replaceable jet nozzle and screwed into the outlet opening of the valve.

EFFECT: more reliable operation of the device.

2 dwg

Description

The invention relates to the oil and gas industries, in particular to downhole equipment for oil and gas fields, and may find application in the passage of fluid from the underlying formation into the overlying formation.

A device for pumping fluid is known (patent RU No. 2198288, IPC E21B 43/00, publ. 02/10/2003), including a hollow body with a cover, bottom and outlet channels for communicating the body cavity with the bottomhole zone of the well, a movable working body and channels supply of the working agent, it is equipped with an additional upper or lower movable working body on the axis of rotation located in a perpendicular plane with respect to the axis of rotation of the existing movable working body, while the upper working body forms working chambers with the housing, one of which of the holes has an outlet channel, and the lower working body forms working chambers with the housing, one of which has an outlet channel, and the outlet channels are made in the form of radial holes with the same cross-sectional area.

The disadvantages of the known device are:

- firstly, the complexity of the design, due to the large number of nodes and parts;

- secondly, it cannot be used when transferring fluid from the underlying formation to the overlying formation.

The closest in technical essence and the achieved result is a device for pumping fluid into the reservoir (patent RU No. 2280152, IPC E21B 43/14, published July 20, 2006), including a hollow body with outlet pipes installed on tubing with thread channels, while the casing is equipped with a casing with holes and a pressure nut, in the annular gap between the casing and the casing there is a spring installed between the lower and upper support washers, installed between the upper support washer and the protrusion on the casing the bone from the inside out, as well as a replaceable nozzle mounted on the casing with the help of a pressure nut, while inside the case between the protrusions on it and coaxially to it is placed a sleeve with holes with the possibility of its shift by a cable technology tool for combining or separating the holes of the sleeve and the casing with the exhaust channels corps.

The disadvantages of the known device are:

- firstly, the complexity of the design, due to the large number of nodes and parts;

- secondly, limited technological capabilities, since when the pressure of the lower aquifer is reduced, it is impossible to pump liquid into the upper oil reservoir through the tubing string from the water conduit located at the wellhead, so the injected fluid will "go" into the lower aquifer ;

- thirdly, to replace the replacement nozzle, it is necessary to disassemble the device (unscrew the pressure nut);

- fourthly, the complex technological process of the device, associated with the use of wireline equipment, and this requires disassembling the wellhead fittings, removing the faceplate, installing rollers, lowering and lifting the load on the geophysical cable into the tubing string in order to move the sleeve relative to the hollow housing;

fifthly, the low reliability of the device in operation, due to the fact that the movement of the sleeve relative to the hollow body does not guarantee the combination or separation of the holes of the sleeve and the casing with the outlet channels of the body, since the sleeve does not have a position lock relative to the hollow body. For the same reason, during the flow of fluid from the lower aquifer to the upper oil reservoir, spontaneous movement of the sleeve relative to the hollow body and, consequently, failure of the device in operation (pumping fluid into the upper oil reservoir) is possible.

An object of the invention is to simplify the design of the device and the technological process of its operation, as well as improving the reliability of the device and expanding the technological capabilities of the device.

The stated technical problem is solved by a device for pumping fluid into the reservoir, including a hollow body mounted on tubing with threads with an outlet channel and a protrusion from below, a sleeve coaxially placed inside the hollow body with axial movement, a replaceable nozzle and a valve that allows fluid to pass from inside to outside .

What is new is that the hollow body is equipped with an inner ring selection from below, while the sleeve is equipped with an outer ring groove at the bottom, in which the retaining ring is installed, the sleeve is fixed relative to the hollow body with a shear element, and on top of the sleeve is equipped with a seating seat for the tubing discharged into the column ball, while the sleeve has the ability to fix relatively hollow body retaining ring after moving down to the stop in the protrusion of the hollow body under the influence of excess hydraulic pressure created in the tubing string above the ball by a pumping unit installed at the wellhead, and an adjustable valve consisting of a downward spring-loaded piston with a stem and an adjusting nut is eccentrically opposite the outlet channel of the hollow body, and a hydraulic chamber is made below the piston in the valve having the ability to communicate with the interior of the hollow body, and under the action of excessive pressure in the hydraulic chamber, the piston has the possibility of axial remescheniya up messages and the hydraulic chamber to the reservoir through the valve outlet, which is provided with a replaceable nozzle screwed into the valve outlet.

Figure 1 shows the proposed device in its original position.

Figure 2 shows the proposed device in the working position.

A device for pumping fluid into a formation includes a hollow body 4 mounted on tubing 1 (see FIG. 1) using threads 2 and 3 with an outlet channel 5 and a projection 6 from below, a sleeve 7 coaxially placed inside the hollow body 4 with the possibility of axial movement.

The hollow body 4 is equipped with a bottom inner ring selection 8.

The sleeve 7 is equipped with a bottom outer ring groove 9, in which a circlip 10 is installed.

The sleeve 7 is fixed relative to the hollow body 4 by a shear element 11, which has the possibility of destruction at overpressure, for example 5.0 MPa. On top of the sleeve 7 is equipped with a landing seat 12 under the ball 13 discharged into the tubing string 1.

The sleeve 7 has the ability to be fixed relative to the hollow body 4 by the retaining ring 10 after moving down to the stop in the protrusion 6 of the hollow body 4 under the action of excessive hydraulic pressure created in the tubing string 1 above the ball 13 (see figure 2) by the pump unit ( 1 and 2 not shown) mounted on the wellhead.

As the retaining ring 10, a split triangular spring ring is used.

Opposite the exhaust channel 5 (see Fig. 1) of the hollow body 4, an adjustable valve 14 is eccentrically installed, consisting of a piston 16 spring-loaded by means of a spring 15 with a rod 17 and an adjusting nut 18.

Below the piston 16 in the valve 14 is a hydraulic chamber 19, which is able to communicate with the inner space 20 of the hollow body 4.

Under the action of excessive pressure in the hydraulic chamber, the piston 16 has the possibility of axial upward movement and communication of the hydraulic chamber 19 with the formation (not shown in Figs. 1 and 2) through the outlet 21 (see Fig. 1) of the valve 14, which is equipped (for example, screwed in) with a replaceable nozzle 22.

The interchangeable nozzle 22 provides an adjustable predetermined flow rate of the liquid, since it changes the cross-sectional area of the outlet 21 of the valve 14 (see figure 2), while the condition must be met:

D> d _i

where, D is the diameter of the exhaust channel 5 of the hollow body 4 mm, for example 20 mm;

d _i - the diameter of the replaceable nozzle 22 of the valve 14 mm, for example 18 mm

Unauthorized fluid flows are eliminated by o-rings mounted on the mating surfaces of the device.

A device for pumping fluid into the reservoir works as follows.

To transfer fluid from the underlying aquifer (not shown in FIGS. 1 and 2) with high reservoir pressure into the overlying oil reservoir with low reservoir pressure, the tubing string 1 (see FIG. 1) is first equipped with a packer of any known design (on 1 and 2 are not shown), and then the proposed device is connected to the tubing string 1 (see Fig. 1).

To do this, the proposed device is attached to the upper pipe of the lower section and to the lower pipe of the upper section of the tubing string 1 using connecting threads 2 and 3.

The tubing string 1 is lowered to the underlying aquifer with high reservoir pressure. In the well between the upper and lower layers, the packer is planted, which is placed between the production string and tubing, i.e. separates the overlying and underlying layers between themselves, while the proposed device for pumping fluid is placed above the overlying formation.

If necessary (with low reservoir pressure of the underlying aquifer), the proposed device can operate with a submersible pump, for example, an electric centrifugal pump, which is placed in the tubing string 1 below the proposed device for pumping fluid from the lower reservoir.

The device is closed (see figure 1), since the sleeve 7 is fixed relative to the hollow body 4 by a shear element 11, and the exhaust channels 5 of the hollow body 4 are hermetically closed by the sleeve 7.

In this position, fluid is pumped from the lower aquifer with high reservoir pressure along the tubing string, for example, to a neighboring well through a system of surface pipelines in order to maintain reservoir pressure.

When it is necessary to start the transfer of fluid from the underlying aquifer with a high reservoir pressure into the overlying reservoir with a low reservoir pressure. From the wellhead into the tubing string 1, a ball 13 is dropped (see FIG. 2), which sits on the landing seat 14 of the sleeve 7, then at the wellhead to the tubing string 1 a pump unit is connected (not shown in FIGS. 1 and 2).

Using a pump unit in the tubing string above the ball 13 create excessive hydraulic pressure, for example 7 MPa, which leads to the destruction of the shear screw 11 and the sleeve 7 is moved down to the stop in the protrusion 6 of the hollow body 4 under the influence of excessive hydraulic pressure in the tubing string 1.

In the proposed device, it is not necessary to disassemble the wellhead fittings, remove the faceplate, install the rollers, carry out the launching of the load on the geophysical cable into the tubing string in order to move the sleeve 7 relative to the hollow body 4, which simplifies the process of the device.

The sleeve 7 is fixed relative to the hollow body 4 by the retaining ring 10 in the inner annular sample 8 of the hollow body 4. As a result, the sleeve 7 is lower than the outlet channel 5 of the hollow body 4 and the outlet channel 5 communicates the inner space 20 of the hollow body 4 with the hydraulic chamber 19 of the adjustable valve 14.

The reliability of the device in operation increases, since the presence of a position lock (retaining ring 10) of the sleeve relative to the hollow body eliminates spontaneous movement of the sleeve during operation of the device, while there is no need to align or separate the holes, since the exhaust channel 5 of the hollow body 4 opens when the sleeve is moved 7 below exhaust channel 5.

Liquid from the lower aquifer with high reservoir pressure from bottom to top along the tubing string 1 through the sleeve 7, the lifting ball 13 enters the interior 20 of the hollow body 4 and through the outlet channel 5 of the hollow body 4, the fluid enters the hydraulic chamber 19 of the valve 14.

Adjustment of the adjustable valve 14 is performed at the wellhead before the device is launched into the well.

The adjustable valve 14 has a tuning range, for example from 0.1 MPa to 0.5 MPa. Regulation is carried out by screwing the adjusting nut 18 into the body of the adjusting valve 14, which leads to the preload of the spring 15.

Thus, the amount of hydraulic pressure that needs to be created in the hydraulic chamber 19 for the valve 14 to act, i.e. for communication of the hydraulic chamber 19 with the formation through the outlet 21 of the valve 14, which is equipped with a replaceable nozzle 22, and in comparison with the prototype for installing the replaceable nozzle 22 there is no need to disassemble the device.

For example, by screwing the adjusting nut 18 into the valve body 14, a pressure equal to 0.4 MPa is set, which must be created in the hydraulic chamber 19 for the valve 14 to operate.

After increasing the pressure in the hydraulic chamber 19 of the valve 14 by 4 MPa, the piston 16, overcoming the force of the spring 15, rises and opens the outlet 21 of the valve 14 and the pumped fluid from the hydraulic chamber 19 of the valve 14 through the interchangeable nozzle 22 enters the annular space between the tubing and the production the column above the packer and further into the overlying formation with low reservoir pressure.

The interchangeable nozzle 22 provides an adjustable predetermined flow rate of the fluid, since it changes the cross-sectional area of the outlet 21 of the valve 14.

After stopping the fluid supply and equalizing (decreasing) the pressure inside the hydraulic chamber 19 of the valve 14 on the one hand and in the annular space between the tubing and the production string above the packer on the other hand, due to the return force of the spring 15, the piston 16 lowers and closes the outlet 21 of the valve 14 in which the replaceable nozzle 22 is installed.

To continue pumping fluid into the upper reservoir with low pressure after depletion of energy (pressure reduction) of the lower aquifer, fluid is injected from the water conduits from the wellhead through the tubing string into the upper reservoir with low reservoir pressure.

During the injection process, the ball 13 located on the seat saddle 14 of the sleeve 7 cuts off the tubing string 1 below the device, so the fluid pumped into the tubing string 1 through the outlet channel 5 of the hollow body 4 enters the hydraulic chamber 19 of the valve 14.

After increasing the pressure in the hydraulic chamber 19 of the valve 14 by 4 MPa, the piston 16, overcoming the force of the spring 15 rises and opens the outlet 21 of the valve 14 and the pumped fluid from the hydraulic chamber 19 of the valve 14 through the interchangeable nozzle 22 enters the annular space between the tubing and the production string above the packer and further into the overlying formation with low reservoir pressure.

The proposed device in comparison with the prototype has the technological ability to pump fluid from the pipelines from the wellhead through the tubing string into the upper oil reservoir with the depletion (decrease in reservoir pressure) of the lower aquifer with high reservoir pressure.

The proposed device for injecting fluid into the reservoir has a simple design and a simple workflow, and also provides high reliability of the device in operation and has advanced technological capabilities in operation.

Claims (1)

A device for pumping fluid into the reservoir, including a hollow body mounted on tubing with threads with an outlet channel and a protrusion from below, a sleeve coaxially placed inside the hollow body with axial movement, a replaceable nozzle and a valve that allows fluid to pass from inside to outside, characterized in that the hollow body is equipped with a bottom inner ring selection, while the sleeve is equipped with a bottom outer ring groove in which the retaining ring is installed, the sleeve is fixed relative to the hollow a shear element, and on top of the sleeve is equipped with a seating seat for a ball being discharged into the tubing string, while the sleeve has the ability to lock the hollow body against the hollow body after moving down into the protrusion of the hollow body under the influence of excess hydraulic pressure generated in the pump string -compressor pipes above the ball pump unit mounted on the wellhead, and opposite the outlet channel of the hollow body eccentrically installed adjustable valve n, consisting of a piston spring-loaded downward with a rod and an adjusting nut, moreover, a hydraulic chamber is arranged below the piston in the valve, which is capable of communicating with the interior of the hollow body, and under the action of excessive pressure in the hydraulic chamber, the piston is able to axially move upward and communicate with the hydraulic chamber formation through the valve outlet, which is equipped with a replaceable nozzle screwed into the valve outlet.

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