RU170983U1 - MECHANICAL DEVICE FOR PROTECTION OF THE FORMATION - Google Patents

Abstract

Usage: protection of the reservoir from the harmful effects of the kill fluid. The device contains a packer 2, a shutoff valve 3, a disconnecting device 6, a hollow pusher 9, a check valve 10, a perforated pipe 11, a sludge trap 12, a process valve 15. The device provides isolation of the reservoir 7 from contact with a heavy killing fluid during repair work on the well. The mechanical complex of formation protection allows research and processing of the productive formation 7. The operation of the device is possible in the layout with any pump. The design of the shut-off valve 3, including the locking element 4 and the channel 5 in the housing, increases the reliability of the device.

Description

Field of technology and purpose

The utility model relates to the oil industry, in particular to devices for protecting the reservoir from the harmful effects of the kill fluid.

State of the art

The invention is known "Method of cutting off the reservoir for underground repairs without killing the well" (patent No. 2592903, RU, ЕВВ 29/00, ЕВВ 34/06, ЕВВ 34/16 published on July 27, 2016). The method includes the use of a continuous packer installation with an anchor mechanism. The installation includes an emergency disconnecting device, a valve assembly with a seat under the ball and a mechanism to prevent the ball from ejecting into the overpacker space. The installation includes telemetry and ball discharge units, directly attached to the bottom of the electric submersible pump. On command from the wellhead, to cut off the formation, the ball is discarded and placed in the seat of the valve assembly with excess pressure. To organize the communication of the pump with the reservoir, re-create excess pressure in the above-packer space and press the ball to the bottom of the well.

The disadvantage of this invention is the difficulty of implementing the technology in terms of calculating the pressure required to force the balls to open and close the valve assembly. In addition, in the aforementioned invention, the operation of the arrangement is possible only with the installation of an electric centrifugal pump, since the control of the ball discharge unit is carried out through the power cable of the ESP.

The invention is known "A method of closing a shutoff valve when removing an electric centrifugal pump from a fountain well and a device for its implementation" (patent No. 2204695, RU, ЕВВ 34/06, published 05/20/2003). The device according to patent No. 2204695 includes a pusher connected to the lower part of the electric centrifugal pump, a movable rod with an orifice that allows the pumped liquid to pass through, and a movable rod clamp. The device is equipped with an overflow valve and additionally contains pistons located on the movable rod, a latch for the upper position of the movable rod and a thrown shut-off element forming a power cylinder. The movable rod is connected to an electric centrifugal pump. In the upper fixed position, the movable rod interacts with the shut-off unit of the bypass valve, opening its openings communicating the internal cavity of the tubing with the cavity of the well. Using the power cylinder, the electric centrifugal pump is moved upward from the position that ensures the productive formation communicates with the well cavity to the position in which the productive formation is disconnected from the well cavity.

The disadvantages of this device is the lack of the possibility of descent into the under-packer space of devices to enable research to monitor the development of the operated facility, as well as technical means for processing the reservoir.

Known "Shut-off valve" (patent No. 2094593, RU, ЕВВ 34/06, F16K 1/20 published on 10.27.1997), comprising a housing with a passage channel, in which a shut-off element is placed in the form of a spring-loaded shutter with an axis of rotation. A spring-closed shut-off valve is opened with a pusher mounted on the lower end of the nipple, lowered on the tubing string.

The disadvantage of this device is the lack of the possibility of its operation in wells where an ESP is used, since the ESP fluid is taken from the annulus, and the design of the device involves lifting the fluid from the sub-packer space through the inner channel of the hermetically connected pusher, pump and tubing. In addition, at the time the valve is opened, it is affected by the static pressure of the kill fluid, causing a pressure differential across the shut-off element. Under certain conditions, the force on the actuator of the shut-off valve necessary to overcome the friction forces and open the locking element can reach significant values, which, together with the structural features of the mechanism, can lead to premature failure of it.

The device according to patent RU 2094593 is the closest in technical essence to the claimed one and is taken as a prototype.

Utility Model Essence

This utility model is aimed at maintaining the productivity of the formation after repair work on the well, carried out using a heavy killing fluid, using a mechanical protection device that is hermetically mounted in the well and has two working positions, in one of which the producing formation is cut off from the pumping area equipment, and in another they are communicated.

The technical task of the claimed utility model is to provide the possibility of conducting research and processing of a productive formation while maintaining its productivity without removing the device, increasing the reliability of the device, expanding its scope.

The problem is solved by the claimed mechanical device for protecting the formation, which contains a housing and a locking element and is connected to the lower end with a packer, and the upper end with a disconnecting device and a hollow pusher.

The technical result is achieved due to the fact that in the known device, the opening of which is carried out mechanically, i.e. By “pressing” the tubing string through the pump and pusher onto the structural elements of the device that open its locking element, an additional channel is organized in the device’s body, which opens and communicates the spaces above and below the device when interacting with the pusher, which makes it possible to equalize the pressure on the locking element of the device before its opening, thereby minimizing the force on the drive mechanism of the device and increasing the reliability of its operation. In this case, a perforated pipe and a check valve are placed between the pump and the pusher. The perforated nozzle ensures the flow of fluid from the reservoir into the annulus, from where it is possible to organize its selection by any pump installation (ESP, EVN, ShGN, ShVN). The non-return valve prevents killing fluid from entering the reservoir when killing the well to change pump equipment. The hollow pusher provides communication between the above-packer and under-packer spaces in the process of fluid selection, as well as the under-packer space and the inner tubing cavity during research and treatment of the reservoir. The presence of a packer and formation protection device allows hermetically disconnecting the productive formation from the zone of placement of pumping equipment. The disconnecting device allows the installation of a protection device for its autonomous operation to separate the spaces above and below the packer. Additionally, if necessary, the system may contain a sludge trap that is installed on the pusher and prevents the packer from sprinkling with mechanical impurities, as well as a process valve that is installed in the upper part of the pusher during research and processing of the reservoir and prevents killing fluid from entering the under-packer space.

The essence of the utility model is illustrated by drawings (Fig. 1-6).

The reservoir protection device 1 includes a shut-off element 2 and a channel 3 in the housing. The device for protecting the formation 1 with a lower end connected to the packer 4, and the upper end with a disconnecting device 5. The specified set of devices descends on the technological string tubing 6 (Fig. 1-2) and is intended for reliable separation of the reservoir 7 and the space above the packer 4.

To communicate the spaces above and below the packer 4 and organize the lifting of liquid from the reservoir on the tubing string 8 (Fig. 3-4), the hollow pusher 9, the check valve 10, the perforated pipe 11, the sludge trap 12, are lowered into the installation interval of the formation protection device 1 pump 13.

To organize research or treatment of the reservoir 7 on the tubing string 14 (Fig. 5-6), the hollow pusher 9 and the process valve 15 are lowered into the interval of installation of the reservoir protection device 1.

The mechanical device for protecting the formation 1 allows to avoid getting the kill fluid into the producing formation 7 during the repair process, which may result in deterioration of the reservoir properties of the formation and a decrease in its flow rate.

A mechanical reservoir protection device operates as follows.

Initially, the tubing 6 is run and installed in the well at a predetermined depth above the reservoir 7 of the composition consisting of: packer 4, protection device 1 and disconnecting device 5 (Fig. 1). Using the disconnecting device 5, the process column 6 is disconnected from the layout and is lifted (Fig. 2). The locking element 2 and channel 3 in the housing of the protection device 1 are closed, the spaces above and below the packer 4 are reliably separated. As a protection device 1, a valve with a mechanical opening device, for example with a ball mechanism or with flaps, can be used.

During the installation of pumping equipment (Fig. 3) on the tubing string 8, the following configuration is launched: pump 13, perforated nozzle 11, non-return valve 10, hollow pusher 9. The space above the packer 4 and the cavity inside the tubing 8 are filled to the mouth with a kill fluid to prevent oil and gas occurrences. During the descent, the check valve 10 is closed. When you enter and seal the hollow pusher 9 in the inner cavity of the protection device 1, the hollow pusher 9 interacts with the elements of the protection device 1, which open the channel 3 in the housing of the protection device 1. As a result, the cavities above and below the protection device 1 communicate and the pressure is equalized to the shut-off element 2. With a further descent of the pusher 9, it interacts with the elements of the protection device 1, which open the locking element 2, after which the pusher 9 is fixed in the protection device 1 (Fig. 4). Since the pressure on the shut-off element 2 is aligned to open it, little effort is required, which increases the reliability of the operation of the protection device 1. As a result, the spaces above and below the packer 4 are communicated through the internal channel of the hollow pusher 9, the check valve 10 and the perforated pipe 11. After starting pump 13, he takes the fluid from the space above the packer 4, the level of the jamming fluid drops, the pressure under the packer 4 becomes higher than the pressure of the column of the kill fluid, the check valve 10 opens formation 7 through the internal channels of the packer 4, the protection device 1, the hollow pusher 9, the check valve 10 and the perforated pipe 11 enters the annulus above the packer 4, from where it is selected by the pump 13. Any installation can be used as the pump 13 (ESP , EVN, ShGN, ShVN), since the selection of fluid is from the annulus. If necessary, the assembly is equipped with a sludge trap 12, which is installed on the pusher 9. The sludge trap 12 is designed to trap those mechanical impurities that come out of the perforated pipe 11 together with the fluid in the reservoir 7, are separated from the general fluid flow and settle on the packer 4. In addition, the sludge trap 12 is an additional degree of protection against the ingress of foreign objects (for example, clams) into the internal channel of the protection device 1, which may affect its performance.

In the case of replacing the pump 13, the annular space above the packer 4 is added to the mouth with a damping fluid. The non-return valve 10 closes, preventing the flow of kill fluid into the reservoir 7. After this, the tubing string 8 pulls the hollow pusher 9 out of the internal cavity of the protection device 1, and the locking element 2 and channel 3 in the housing of the protection device 1 are sequentially closed (Fig. .3), the spaces above and below the packer are disconnected 4. On the tubing string 8, the assembly is lifted consisting of: pump 13, perforated pipe 11, check valve 10, sludge trap 12, hollow pusher 9. Packer 4 remaining in the well and closed The first protection device 1 reliably separates the under-packer and over-packer spaces (Fig. 2), not allowing the kill fluid to enter the reservoir 7. Reinstallation of the pump 13 is carried out similarly to the process of the initial installation of the pump.

If it is necessary to conduct research or treatment of the reservoir 7, the pump 13 is lifted by analogy with the operation of lifting it for replacement. After that, the technological string tubing 14 with a hollow pusher 9 is lowered into the well filled with the kill fluid, and, if necessary, with the technological valve 15 (Fig. 5) located above the pusher 9. The technological valve 15 is closed during the descent and protects the inner cavity of the process column 14 from filling the jamming fluid 14. When the hollow pusher 9 enters and seals in the inner cavity of the protection device 1, the hollow pusher 9 interacts with the elements of the protection device 1, which open channel 3 in the housing of the protection device 1. As a result, the cavities above and below the protection device 1 and the pressure equalizes on the locking element 2. When the pusher 9 is further released, it interacts with the elements of the protective device 1, which open the locking element 2, after which the pusher 9 is fixed in the protection device 1. After this, the force from the weight of the process column 14 is transmitted to the process valve 15, as a result of which it opens (Fig. 6). Due to the fact that during the descent, the valve 15 was closed, in the inner cavity of the technological column 14 there is no kill fluid that could enter the reservoir when all the valves are opened. The silencing fluid from the annulus also does not enter the reservoir 7, since the internal channels of the packer 4, the protection device 1, the hollow pusher 9, the process valve 15 and the tubing string 14 form a sealed channel from the space under the packer 4 to the mouth. The combination of these channels forms a full bore channel, which allows descent into the under-packer space of instruments for conducting research to control the development, as well as means for processing the reservoir 7. After completion of the work, the process string is tensioned 14. The process valve 15 closes, after whereby the force is transmitted to the hollow plunger 9, which leaves the inner cavity of the protection device 1, while the locking element is sequentially closed NT 2 and channel 3 in the housing of the protection device 1 (Fig. 5), the spaces above and below the packer 4 are disconnected. On the technological string tubing 14, the process valve 15 and the hollow follower 9 are lifted. The remaining packer 4 and the closed protection device 1 are reliably Separate subpacker and superpacker spaces. Reinstallation of the pump 13 is carried out similarly to the initial installation of the pump.

Thus, a mechanical reservoir protection device allows you to maintain reservoir productivity after repair work on the well, as well as after its research and treatment, by ensuring the formation is isolated from contact with a heavy killing fluid.

Claims (1)

A mechanical reservoir protection device comprising a housing and a locking element connected to the lower end with a packer, and the upper end to a disconnecting device, characterized in that the housing contains an additional channel for balancing the pressure above and below the protection device.

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