CN211851763U

CN211851763U - External packer for casing

Info

Publication number: CN211851763U
Application number: CN201922377971.9U
Authority: CN
Inventors: 肖国华; 刘宇飞; 黄欣; 王金忠; 强晓光
Original assignee: Petrochina Co Ltd
Current assignee: Petrochina Co Ltd
Priority date: 2019-12-25
Filing date: 2019-12-25
Publication date: 2020-11-03
Anticipated expiration: 2029-12-25

Abstract

The utility model provides an outer packer of sleeve pipe, this outer packer of sleeve pipe includes: the pipe wall of the central pipe is provided with a liquid inlet hole communicated with the inner cavity of the central pipe; the installation cylinder is coaxially sleeved outside the central pipe, one end of the installation cylinder is in sealing fit with the central pipe, and a first annular space communicated with the liquid inlet hole is formed between the installation cylinder and the central pipe; the expansion rubber cylinder is coaxially sleeved outside the central pipe, one end of the expansion rubber cylinder is connected with the other end of the mounting cylinder, the other end of the expansion rubber cylinder is in sealing fit with the central pipe, a second annular space is formed between the expansion rubber cylinder and the central pipe, and the first annular space is communicated with the second annular space; and an encapsulation medium filled in the second annular space, the encapsulation medium being configured to react with water to produce a cured product. The utility model discloses can effectively avoid the packing element of the outer packer of sleeve pipe to appear leaking and caving because of the clear water of packing, improve sealed effect.

Description

External packer for casing

Technical Field

The utility model relates to an oil field development well completion, well cementation technical field, in particular to bushing outer packer.

Background

When the well is developed and completed in an oil and gas field and the well is fixed, the outer packer of the casing is required to be adopted to pack the shaft and the casing for a long time according to the process requirements, so that the packer is required to be effective for a long time after being set. The casing outer packer is a downhole tool connected with a casing and used for packing the casing outer annular space (namely the annular space between the casing and the inner wall of a shaft), can effectively pack oil, gas and water layers, selectively exploit or pack a certain section, and ensure the sealing of the casing outer annular space. The casing external packer can obviously improve the well cementation quality, effectively perform interlayer packing, avoid or reduce oil layer pollution and provide guarantee for improving the crude oil recovery rate and the exploitation efficiency.

In the related art, the external casing packer is mostly a hydraulic expansion type external casing packer. The hydraulic expansion type casing external packer comprises a central pipe and a rubber cylinder sleeved on the central pipe, wherein the central pipe is provided with a through hole communicated with the rubber cylinder. When clean water is added from the central pipe to be pressurized, the clean water enters the inner cavity of the rubber cylinder through the through hole in the central pipe, the rubber cylinder is forced to expand outwards to be tightly attached to the inner wall of the shaft, and the annular space between the sleeve and the inner wall of the shaft is sealed.

However, after the casing pipe outer packer in the related art is used for a period of time, the situation that clean water leaks from the rubber cylinder frequently occurs, and the sealing effect of the casing pipe outer packer is affected; in addition, after the water is injected into the rubber tube and the rubber tube is expanded, the inner side wall and the outer side wall of the rubber tube are respectively subjected to the acting force of hydraulic pressure and a well wall, so that the side wall of the rubber tube is thinned, and the inner wall of the well shaft is rough, so that the rubber tube is easily scratched, and the sealing effect of the packer outside the casing tube is also influenced.

SUMMERY OF THE UTILITY MODEL

The utility model provides a casing pipe outer packer can effectively avoid the packing element of casing pipe outer packer to appear leaking and caving because of the clear water of packing, improves sealed effect. The technical scheme is as follows:

the utility model provides an outer packer of sleeve pipe, the outer packer of sleeve pipe includes: the pipe wall of the central pipe is provided with a liquid inlet hole communicated with the inner cavity of the central pipe; the installation cylinder is coaxially sleeved outside the central pipe, one end of the installation cylinder is in sealing fit with the central pipe, and a first annular space communicated with the liquid inlet hole is formed between the installation cylinder and the central pipe; the expansion rubber cylinder is coaxially sleeved outside the central tube, one end of the expansion rubber cylinder is connected with the other end of the mounting tube, the other end of the expansion rubber cylinder is in sealing fit with the central tube, a second annular space is formed between the expansion rubber cylinder and the central tube, and the first annular space is communicated with the second annular space; an encapsulation medium filled in the second annular space, the encapsulation medium configured to react with water to produce a cured product.

In an implementation of the present invention, the packing medium is a chemical blocking agent made of acrylamide.

In another implementation of the present invention, the expansion rubber cylinder includes: the rubber tube mounting structure comprises a first rubber tube joint, a second rubber tube joint, an inner rubber tube, an outer rubber tube and an elastic metal sheet which are coaxially sleeved on a central tube, wherein one end of the first rubber tube joint is connected with the other end of a mounting tube, the other end of the first rubber tube joint is connected with one end of the outer rubber tube, the outer rubber tube is sleeved on the inner rubber tube, two opposite side faces on the elastic metal sheet are respectively connected with the inner wall of the outer rubber tube and the outer wall of the inner rubber tube in a laminating manner, the other end of the outer rubber tube is connected with one end of the second rubber tube joint, the outer wall of one end of the inner rubber tube is connected with the inner wall of the first rubber tube joint, the other end of the inner rubber tube is connected with the inner wall of the second rubber tube joint, and the other end of the second rubber tube joint is in sealing fit with the central tube.

The utility model discloses an among another kind of implementation, the outer packer of sleeve pipe includes one-way feed liquor valve, one-way feed liquor valve is located in the first annular space, the inlet and the first annular space intercommunication of one-way feed liquor valve, the liquid outlet of one-way feed liquor valve with second annular space intercommunication.

The utility model discloses an among another kind of implementation, the installation section of thick bamboo includes the valve body mount pad, the coaxial suit of valve body mount pad is in outside the center tube, the valve body mount pad with the sealed cooperation of center tube, the valve body mount pad cuts off first annular space, be equipped with on the valve body mount pad link up in the axial of center tube the runner of valve body mount pad, the runner with the inlet intercommunication of one-way feed liquor valve.

The utility model discloses an among another kind of implementation, one-way feed liquor valve has a plurality ofly, and is a plurality of one-way feed liquor valve circumference interval is arranged.

The utility model discloses an among another kind of implementation, one-way feed liquor valve includes valve barrel, case and spring, the case is followed the endwise slip of valve barrel sets up in the valve barrel, the one end interpolation of valve barrel is equipped with the annular packing pad, the sealed internal diameter of annular packing is less than the external diameter of case, the one end of spring with the case offsets, the other end of spring with backstop structure on the inner wall of valve barrel offsets.

The utility model discloses an among another kind of implementation, the outer packer of sleeve pipe still includes the releasing piston, the releasing piston slidable sets up in the first annular space, the releasing piston shutoff the inlet of one-way feed liquor valve, the releasing piston with have between the center tube with the working chamber of feed liquor hole intercommunication, the releasing piston passes through the shear pin to be fixed on the installation section of thick bamboo, the releasing piston is configured to be able to liquid pressure effect removes down in the working chamber, makes the inlet of one-way feed liquor valve with feed liquor hole intercommunication.

The utility model discloses an in another kind of implementation, the outer packer of sleeve pipe still includes first coupling and second coupling, the outer wall of the one end of first coupling with the one end threaded connection of an installation section of thick bamboo, the inner wall of the one end of first coupling with the one end threaded connection of center tube, the inner wall of the one end of second coupling with the other end threaded connection of center tube.

The utility model discloses an among another kind of implementation, be equipped with on the installation section of thick bamboo with the injection mouth of first annular space intercommunication, the plug head is equipped with in the injection mouth, the other end of expansion packing element is equipped with the gas vent, the plug head is equipped with in the gas vent.

The utility model provides a beneficial effect that technical scheme brought includes at least:

the utility model provides an installation section of thick bamboo in the outer packer of sleeve pipe, the equal coaxial suit of expansion packing element is outside the center tube, wherein, the one end and the sealed cooperation of center tube of an installation section of thick bamboo, the other end of an installation section of thick bamboo and the one end of expansion packing element are connected, and the other end and the sealed cooperation of center tube of expansion packing element, the installation section of thick bamboo constitutes confined space with the expansion packing element jointly with the center tube promptly, and simultaneously, the feed liquor hole has on the center tube, and the first annular space intercommunication between feed liquor hole and installation section of thick bamboo and the center tube, the second annular space between first annular space and expansion packing element and the center tube also is the intercommunication simultaneously, and thus, when suppressing through to the sleeve pipe water injection, the clear water just can enter into in the expansion packing element through the. And the second annular space is filled with a packing medium which can react with water to generate a condensate, so that when the casing is injected with water and pressed, clear water flowing into the expansion rubber sleeve reacts with the packing medium to generate the condensate, the condensate is filled in the expansion rubber sleeve and added with the pressure of the clear water, the expansion rubber sleeve is expanded to be tightly attached to the inner wall of the shaft, and the purpose of sealing the annular space between the casing and the inner wall of the shaft is achieved. Because the sealing medium and the water react to generate a cured substance in the expansion rubber cylinder, namely the expansion rubber cylinder is supported by the cured substance, the clean water leaks from the expansion rubber cylinder after being used for a period of time, and the expansion rubber cylinder cannot be easily loosened; even if the expansion rubber cylinder is scratched, the expansion rubber cylinder is filled with the cured substance, so that the expansion rubber cylinder cannot be loosened due to leakage, the rubber cylinder of the casing outer packer can be effectively prevented from leaking, and the sealing effect is improved.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

Fig. 1 is a schematic structural diagram of an external casing packer according to an embodiment of the present invention;

fig. 2 is a schematic partial structural view of an external casing packer according to an embodiment of the present invention;

fig. 3 is a partial schematic structural view of another casing external packer provided by an embodiment of the present invention;

fig. 4 is a schematic structural view of a one-way liquid inlet valve provided in the embodiment of the present invention;

fig. 5 is a schematic structural diagram of an expansion rubber sleeve according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

Fig. 1 is a schematic structural view of an external casing packer according to an embodiment of the present invention. As shown in fig. 1, the external casing packer comprises: the device comprises a central tube 1, an installation tube 2, an expansion rubber tube 3 and packing media. The pipe wall of the central pipe 1 is provided with a liquid inlet hole 11 communicated with the inner cavity of the central pipe 1; the installation cylinder 2 is coaxially sleeved outside the central tube 1, one end of the installation cylinder 2 is in sealing fit with the central tube 1, and a first annular space 12 communicated with the liquid inlet hole 11 is formed between the installation cylinder 2 and the central tube 1; the expansion rubber cylinder 3 is coaxially sleeved outside the central tube 1, one end of the expansion rubber cylinder 3 is connected with the other end of the mounting tube 2, and the other end of the expansion rubber cylinder 3 is in sealing fit with the central tube 1; a second annular space 13 is formed between the expandable rubber sleeve 3 and the central tube 1, the first annular space 12 is communicated with the second annular space 13, and a packing medium is filled in the second annular space 13 and is configured to react with water to generate a solidified substance.

The embodiment of the utility model provides an installation section of thick bamboo in the outer packer of sleeve pipe, the equal coaxial suit of expansion packing element is outside the center tube, wherein, the one end and the sealed cooperation of center tube of installation section of thick bamboo, the other end of installation section of thick bamboo and the one end of expansion packing element are connected, and the other end and the sealed cooperation of center tube of expansion packing element, installation section of thick bamboo and expansion packing element constitute confined space with the center tube jointly promptly, and simultaneously, the feed liquor hole has on the center tube, and the first annular space intercommunication between feed liquor hole and installation section of thick bamboo and the center tube, the second annular space between first annular space and expansion packing element and the center tube also communicates simultaneously, thus, when suppressing through to the sleeve pipe water injection, the clear water just can enter into in the expansion packing element through the feed liquor hole. And the second annular space is filled with a packing medium which can react with water to generate a condensate, so that when the casing is injected with water and pressed, clear water flowing into the expansion rubber sleeve reacts with the packing medium to generate the condensate, the condensate is filled in the expansion rubber sleeve and added with the pressure of the clear water, the expansion rubber sleeve is expanded to be tightly attached to the inner wall of the shaft, and the purpose of sealing the annular space between the casing and the inner wall of the shaft is achieved. Because the sealing medium and the water react to generate a cured substance in the expansion rubber cylinder, namely the expansion rubber cylinder is supported by the cured substance, the clean water leaks from the expansion rubber cylinder after being used for a period of time, and the expansion rubber cylinder cannot be easily loosened; even if the expansion rubber cylinder is scratched, the expansion rubber cylinder is filled with the cured substance, so that the expansion rubber cylinder cannot be loosened due to leakage, the rubber cylinder of the casing outer packer can be effectively prevented from leaking, and the sealing effect is improved.

The embodiment of the utility model provides an in, the packing medium can be a chemical plugging agent, and this chemical plugging agent is immiscible with oil, does not react, and expands with the water reaction, generates the resin consolidation body, and intensity is high, elasticity, can support expansion packing element 3, realizes permanent effective packing stratum.

The blocking medium can be acrylamide material chemical blocking agent, which comprises acrylamide, oxygen scavenger, ammonium persulfate and cross-linking agent, wherein, after the acrylamide is in water, the acrylamide reacts with the water to generate a water-insoluble gel consolidation body with certain strength; the oxygen scavenger is arranged in the chemical plugging agent, so that moisture in the environment can be absorbed, the chemical plugging agent is kept dry, and the chemical plugging agent is prevented from reacting before reacting with clear water, for example, the oxygen scavenger can be iron powder, calcium oxide powder and the like; ammonium persulfate is arranged in the chemical plugging agent and can be used as a curing agent to adjust the speed of acrylamide solidified into a gel solidification body; the chemical blocking agent is provided with a cross-linking agent which can improve the strength and elasticity of the generated gel consolidation body, for example, the cross-linking agent can be sulfur.

It should be noted that the oxygen scavenger and the cross-linking agent may be other chemicals besides the above exemplified chemicals, as long as the use requirements are met, and this embodiment is not limited.

Fig. 2 is a schematic view of a partial structure of an external casing packer according to an embodiment of the present invention. Fig. 3 is a schematic partial structural view of another casing external packer according to an embodiment of the present invention. The outer casing packer shown in fig. 2 is butted with the outer casing packer shown in fig. 3 to form the complete outer casing packer shown in fig. 1.

Optionally, the external casing packer may further include a one-way liquid inlet valve 23, the one-way liquid inlet valve 23 is located in the first annular space 12, a liquid inlet 232 of the one-way liquid inlet valve 23 is communicated with the first annular space 12, and a liquid outlet 233 of the one-way liquid inlet valve 23 is communicated with the second annular space 13.

As shown in fig. 1, 2, and 3, the installation cylinder 2 includes a connection cylinder 21 and a valve body installation seat 22, the connection cylinder 21 and the valve body installation seat 22 are all coaxially sleeved on the central tube 1, one end of the connection cylinder 21 is connected with one end of the expansion rubber cylinder 3, the other end of the connection cylinder 21 is connected with one end of the valve body installation seat 22, and the valve body installation seat 22 is in sealing fit with the central tube 1, namely, the valve body installation seat 22 separates the first annular space 12 into two spaces, and the valve body installation seat 22 is further provided with a flow channel 231 penetrating through the valve body installation seat 22 in the axial direction of the central tube, namely, the two spaces separated by the valve body installation seat 22 are communicated through the flow channel 231.

Wherein, one end of the connecting cylinder 21 can be provided with an external thread so as to facilitate the threaded connection of the connecting cylinder 21 and one end of the first rubber cylinder joint 31 of the expansion rubber cylinder 3. Meanwhile, the other end of the connecting cylinder 21 is also inserted with a valve body mounting seat 22, that is, the annular space between the connecting cylinder 21 and the central tube 1 is one of two spaces separated by the valve body mounting seat 22, and the other of the two spaces separated by the valve body mounting seat 22 is communicated with the liquid inlet hole 11.

In this embodiment, the one-way liquid inlet valve 23 may be installed at one end of the valve body installation seat 22, the one-way liquid inlet valve 23 is located in an annular space between the connection cylinder 21 and the central tube 1, and the liquid inlet 232 of the one-way liquid inlet valve 23 is communicated with the flow channel 231, so that the liquid inlet 232 of the one-way liquid inlet valve 23 is communicated with the first annular space 12, and clean water can flow to the one-way liquid inlet valve 23 through the liquid inlet hole 11 and the flow channel 231 in sequence. Because the one-way liquid inlet valve 23 only allows the fluid to enter the valve from the liquid inlet 232 and flow out from the liquid outlet 233 of the one-way liquid inlet valve 23 when the hydraulic pressure of the fluid is greater than a certain value, but does not allow the fluid to flow back out of the one-way liquid inlet valve 23 from the liquid inlet 232, after the clean water is injected into the expansion rubber cylinder 3, the clean water is sealed and locked in the annular space between the connecting cylinder 21 and the central tube 1, so as to keep the pressure applied by the clean water to the expansion rubber cylinder 3, prevent the clean water from easily leaking, and improve the sealing effect of the packer outside the casing.

In this embodiment, the valve body mounting seat 22 may be a cylindrical structure, a sealing ring 4 is disposed between the outer wall of the end portion of the valve body mounting seat 22 and the connecting cylinder 21, and a sealing ring 4 is disposed between the inner wall of the end portion of the valve body mounting seat 22 and the central tube 1, so that both ends of the valve body mounting seat 22 may be connected with the central tube 1 and the connecting cylinder 21 in a sealing manner. The flow passage 231 of the valve body mounting seat 22 may pass through the valve body mounting seat 22 from one end to the other end thereof.

For example, as shown in fig. 2, an annular groove may be formed in the middle of the valve body mounting seat 22, so that an annular space is formed between the middle of the valve body mounting seat 22 and the central pipe 1, so that the flow channels 231 penetrating through the two ends of the valve body mounting seat 22 can collect clean water in the valve body mounting seat 22, so that the clean water can be rapidly pressurized in the valve body mounting seat 22 to open the valve core 235 of the one-way liquid inlet valve 23.

Optionally, there are a plurality of one-way liquid inlet valves 23, and the plurality of one-way liquid inlet valves 23 are circumferentially arranged at intervals at one end of the valve body mounting seat 22. Meanwhile, the arrangement of the plurality of one-way liquid inlet valves 23 facilitates quick addition of clean water into the expansion rubber cylinder 3, and the problem that the sleeve outer packer cannot normally work due to the fact that individual one-way liquid inlet valves 23 are damaged and the valve core 235 cannot be opened is solved, and reliability is improved.

Exemplarily, fig. 4 is a schematic structural diagram of a one-way liquid inlet valve provided by an embodiment of the present invention. As shown in fig. 4, the one-way liquid inlet valve 23 includes a valve sleeve 234, a valve core 235 and a spring 236, one end of the valve sleeve 234 is inserted into one end of the valve body mounting seat 22, the valve core 235 is disposed in the valve sleeve 234 in an axially sliding manner along the valve sleeve 234, an annular gasket 237 is inserted into one end of the valve sleeve 234, an inner diameter of the annular gasket 237 is smaller than an outer diameter of the valve core 235, one end of the spring 236 abuts against the valve core 235, and the other end of the spring 236 abuts against a stop structure on an inner wall of the valve sleeve 234. Wherein, the valve core 235 is cone-shaped, and one end of the valve core 235 is provided with a guide rod, the spring 236 is sleeved on the guide rod, one end of the spring 236 abuts against the valve core 235, the other end of the spring 236 abuts against a spigot on the inner wall of the valve sleeve 234, the spring 236 is always in a compression state, so that the valve core 235 can always abut against the annular sealing gasket 237 at one end of the valve sleeve 234 when not pressed, the annular sealing gasket 237 is arranged to abut against the valve core 235, and abrasion of the valve core 235 in the process of repeatedly opening and closing the valve core 235 can be prevented, and because the annular sealing gasket 237 is soft, the annular sealing gasket 237 can be compressed after the valve core 235 abuts against the annular sealing gasket 237, so that the loop line sealing gasket is tightly attached to the valve core 235, and the sealing performance.

Optionally, as shown in fig. 4, a plurality of liquid outlets 233 are provided on the outer wall of the valve sleeve 234, and a plurality of liquid outlets 233 are provided, so that clean water can rapidly flow out of the valve sleeve 234 and flow into the expansion glue cylinder 3, so that the expansion glue cylinder 3 is rapidly expanded and deformed. The arrangement of the liquid outlets 233 includes at least one of the following arrangements: the liquid outlets 233 are spaced axially along the valve sleeve 234; the outlet ports 233 are spaced circumferentially of the valve sleeve 234.

Here, the liquid outlets 233 may be arranged at intervals only along the axial direction of the valve sleeve 234, or may be arranged at intervals only along the circumferential direction of the valve sleeve 234, or may also be arranged at intervals along the axial direction of the valve sleeve 234 at the same time.

Illustratively, as shown in fig. 4, three layers of liquid outlets 233 are arranged on the outer wall of the valve sleeve 234 at intervals along the axial direction of the valve sleeve 234, and each layer of liquid outlets 233 includes a plurality of liquid outlets 233 arranged at intervals along the circumferential direction of the valve sleeve 234, so that more liquid outlets 233 can be arranged on the valve sleeve 234 in the arrangement manner of the liquid outlets 233, so that clean water can rapidly flow out of the valve sleeve 234 and flow into the expansion rubber cylinder 3, and the expansion rubber cylinder 3 is rapidly expanded and deformed.

Optionally, as shown in fig. 3, in order to facilitate filling of the packing medium into the expansion rubber cylinder 3, an injection port 210 communicating with the first annular space 12 may be further provided on the mounting cylinder 2, and a packing head 6 is inserted into the injection port 210. The other end of the expansion rubber cylinder 3 is provided with an exhaust port 50, and a plugging head 6 is inserted into the exhaust port 50.

Illustratively, as shown in fig. 2 and 3, an injection port 210 communicating with the annular space of the connecting cylinder 21 and the central tube 1 may be provided on the outer wall of the connecting cylinder 21, and the plugging head 6 may be inserted into the injection port 210. The gas vent 50 sets up the other end at expansion packing element 3, and plug head 6 is inserted in the gas vent 50, can open simultaneously with notes agent mouth 210 and gas vent 50 earlier when pouring into the packing medium into expansion packing element 3, pours into the packing medium into to expansion packing element 3 through annotating agent mouth 210 like this, can arrange the air in the expansion packing element 3 to the greatest extent to make expansion packing element 3 can fill the packing medium smoothly.

Optionally, as shown in fig. 1 and 2, the external casing packer further includes a releasing piston 25, the releasing piston 25 is slidably disposed in the first annular space 12, the releasing piston 25 blocks the liquid inlet 232 of the one-way liquid inlet valve 23, a working chamber 26 communicated with the liquid inlet hole 11 is provided between the releasing piston 25 and the central pipe 1, the releasing piston 25 is fixed on the mounting barrel 2 by a shear pin 7, and the releasing piston 25 is configured to be movable under the action of liquid pressure in the working chamber 26, so that the liquid inlet 232 of the one-way liquid inlet valve 23 is communicated with the liquid inlet hole 11.

Illustratively, as shown in fig. 1 and 2, the mounting cylinder 2 may further include a piston sleeve 24, the piston sleeve 24 is coaxially sleeved on the central tube 1, one end of the piston sleeve 24 is connected with the other end of the valve body mounting seat 22, that is, an annular space between the piston sleeve 24 and the central tube 1 is the other of the two spaces separated by the valve body mounting seat 22, and the annular space is communicated with the liquid inlet hole 11. The releasing piston 25 is arranged in the annular space between the piston sleeve 24 and the central pipe 1 in a sliding manner, the releasing piston 25 abuts against a flow channel 231 which is arranged at the other end of the valve body mounting seat 22 and is communicated with the liquid outlet 233 of the one-way liquid inlet valve 23, a working cavity 26 communicated with the liquid inlet hole 11 is arranged between the releasing piston 25 and the other end of the valve body mounting seat 22, and the releasing piston 25 is fixed on the inner wall of the piston sleeve 24 through a shear pin 7.

Wherein, a valve body mounting seat 22 is inserted into one end of the piston sleeve 24, that is, the other end of the valve body mounting seat 22 is inserted into the piston sleeve 24, and the flow passage 231 of the valve body mounting seat 22 is communicated with the inner cavity of the piston sleeve 24. The other end of the connecting cylinder 21 is inserted with a valve body mounting seat 22, that is, one end of the valve body mounting seat 22 is inserted into the connecting cylinder 21, and the flow passage 231 of the valve body mounting seat 22 is communicated with the inner cavity of the connecting cylinder 21. As shown in fig. 1 and 2, an annular protrusion is disposed in the middle of the valve body mounting seat 22, and the piston sleeve 24 and the connecting cylinder 21 are respectively sleeved on two sides of the annular protrusion, so that the piston sleeve 24 and the connecting cylinder 21 are accurately positioned and mounted on the valve body mounting seat 22.

In this embodiment, a seal ring 4 is arranged between the outer wall of the end of the valve body mounting seat 22 and the piston sleeve 24, and a seal ring 4 is arranged between the inner wall of the end of the valve body mounting seat 22 and the central tube 1, so that both ends of the valve body mounting seat 22 can be connected with the central tube 1 and the connecting cylinder 21 in a sealing manner. Meanwhile, a releasing piston 25 is arranged in the annular space between the piston sleeve 24 and the central pipe 1 in a sliding manner, a sealing ring 4 can be arranged between the releasing piston 25 and the central pipe 1 and between the releasing piston 25 and the piston sleeve 24 to improve the sealing performance, the releasing piston 25 is fixed on the inner wall of the piston sleeve 24 through a shear pin 7, and a working cavity 26 communicated with the liquid inlet hole 11 is arranged between the releasing piston 25 and the other end of the valve body mounting seat 22, so that when clean water is injected into the central pipe 1 in a pressurizing manner, the clean water can enter the working cavity 26 through the liquid inlet hole 11, when the pressure of the clean water is large enough, the releasing piston 25 is pushed to move and shear the shear pin 7, as shown in fig. 2, a sliding space 250 for the releasing piston 25 to slide is also arranged above the releasing piston 25, an air hole 251 communicated with the sliding space 250 is also arranged on the piston sleeve 24, and the air hole 251 is used for discharging the air in the sliding space 250 when the, so that the releasing piston 25 can slide in the sliding space 250. Thus, when the releasing piston 25 and the other end of the valve body mounting seat 22 are separated from each other, the clean water in the working chamber 26 can flow into the flow passage 231, and smoothly enter the expansion rubber cylinder 3 after passing through the one-way liquid inlet valve 23.

Optionally, as shown in fig. 1, 2 and 3, the external casing packer further comprises a first pipe joint 27 and a second pipe joint 28, wherein the outer wall of one end of the first pipe joint 27 is in threaded connection with one end of the installation cylinder 2, the inner wall of one end of the first pipe joint 27 is in threaded connection with one end of the central pipe 1, and the inner wall of one end of the second pipe joint 28 is in threaded connection with the other end of the central pipe 1.

Illustratively, as shown in fig. 1, an outer wall of one end of the first pipe joint 27 may be screwed with an inner wall of the other end of the piston sleeve 24, and an inner wall of the first pipe joint 27 is screwed with the center pipe 1. The other end of the first pipe connector 27 is also provided with internal threads to facilitate connection of the first pipe connector 27 to the sleeve, allowing the quick assembly of the external sleeve packer to the sleeve.

Illustratively, the inner wall of one end of the second pipe joint 28 is threadedly connected to the base pipe 1. Wherein the other end of the second pipe joint 28 is also provided with an internal thread to facilitate the connection of the second pipe joint 28 with the sleeve, so that the assembly of the external packer of the sleeve with the sleeve can be completed quickly.

Fig. 5 is a schematic structural diagram of an expansion rubber sleeve according to an embodiment of the present invention. As shown in fig. 5, the expanding rubber tube 3 includes: equal coaxial suit is in first packing element joint 31 on center tube 1, second packing element joint 32, interior packing element 33, outer packing element 34 and elastic metal piece 35, the one end of first packing element joint 31 is connected with the other end of installation section of thick bamboo 2, the other end of first packing element joint 31 is connected with the one end of outer packing element 34, outer packing element 34 cover is established on interior packing element 33, the outer both sides face that is relative on the elastic metal piece 35 is connected with the inner wall laminating of outer packing element 34 and the outer wall of interior packing element 33 respectively, the other end of outer packing element 34 is connected with the one end of second packing element joint 32, the outer wall of the one end of interior packing element 33 and the inner wall connection of first packing element joint 31, the other end of interior packing element 33 and the inner wall connection of second packing element joint 32, the other end and the center tube 1 sealing fit of second packing element joint 32.

The first rubber cylinder joint 31 and the second rubber cylinder joint 32 can be of a cylinder structure, one end of the first rubber cylinder joint 31 can be sleeved at the other end of the installation cylinder 2, the first rubber cylinder joint can be in threaded connection with the outer wall of the installation cylinder 2, and in order to improve the sealing performance, a sealing ring 4 can be arranged at the connection position of the first rubber cylinder joint 31 and the installation cylinder 2; similarly, one end of the second glue cartridge joint 32 can be sleeved on the central tube 1, and the second glue cartridge joint 32 can be screwed with the outer wall of the central tube 1.

In this embodiment, as shown in fig. 1 and 3, the external casing packer may further include: rubber sleeve adapter sleeve 5, the one end of rubber sleeve adapter sleeve 5 is connected with the one end of second rubber sleeve joint 32, be equipped with the external screw thread on the outer wall of rubber sleeve adapter sleeve 5 to second rubber sleeve joint 32 and rubber sleeve adapter sleeve 5 threaded connection, for improving the leakproofness, the junction of second rubber sleeve joint 32 and rubber sleeve adapter sleeve 5 can also set up sealing washer 4, and rubber sleeve adapter sleeve 5 cover is established on center tube 1, be equipped with sealing washer 4 between rubber sleeve adapter sleeve 5 and the center tube 1, so that rubber sleeve adapter sleeve 5 and center tube 1 sealing fit.

The inner rubber cylinder 33 and the outer rubber cylinder 34 may be made of a material with good elasticity, for example, rubber cylinders made of rubber material, so that the inner rubber cylinder 33 and the outer rubber cylinder 34 are easy to expand and deform. Through setting up two-layer packing element inside and outside, can improve the thickness of expansion packing element 3 to guarantee the intensity of expansion packing element 3, prevent that expansion packing element 3 from being worn out easily. Meanwhile, an elastic metal sheet 35 is further arranged between the inner rubber cylinder 33 and the outer rubber cylinder 34, two side faces of the elastic metal sheet 35 are respectively attached to the inner rubber cylinder 33 and the outer rubber cylinder 34, namely, the expansion rubber cylinder 3 is supported by the elastic metal sheet 35, and the strength of the expansion rubber cylinder 3 is improved.

Optionally, as shown in fig. 1, 3, and 5, two ends of the outer glue cylinder 34 may be respectively fixedly connected to end portions of the first glue cylinder joint 31 and the second glue cylinder joint 32, two ends of the inner glue cylinder 33 may be respectively attached to inner walls of the first glue cylinder joint 31 and the second glue cylinder joint 32, in order to prevent the inner glue cylinder 33 from sliding axially after being attached, a plurality of annular protrusions may be disposed on outer walls of two ends of the inner glue cylinder 33, a plurality of annular grooves matched with the annular protrusions may be disposed on inner walls of the first glue cylinder joint 31 and the second glue cylinder joint 32, and the inner glue cylinder 33 is attached to the first glue cylinder joint 31 and the second glue cylinder joint 32, and the axial sliding of the inner glue cylinder 33 is limited by matching of the annular grooves and the annular protrusions.

Alternatively, in order to lock the inner rubber tube 33 on the first rubber tube joint 31 and the second rubber tube joint 32, a lock female joint 36 may be further provided on an inner wall of the inner rubber tube 33, an external thread is provided on an outer wall of the lock female joint 36, the lock female joint 36 is fixed on the inner wall of the inner rubber tube 33 by the external thread, and since the lock female joint 36 is a hard member and the first rubber tube joint 31 and the second rubber tube joint 32 are both hard members, the inner rubber tube 33 can be clamped between the lock female joint 36 and the first rubber tube joint 31 and the second rubber tube joint 32 to lock the inner rubber tube 33.

For example, the elastic metal sheet 35 may be cylindrical, that is, the cylindrical elastic metal sheet 35 is sleeved outside the inner rubber tube 33 and is covered by the outer rubber tube 34, so that the cylindrical elastic metal sheet 35 is located between the inner rubber tube 33 and the outer rubber tube 34 to support the inner rubber tube 33 and the outer rubber tube 34 to form a framework of the expanding rubber tube 3, thereby enhancing the strength of the expanding rubber tube 3.

The number of the cylindrical elastic metal sheets 35 may be plural, and the plural cylindrical elastic metal sheets 35 are coaxially nested together, that is, the plural elastic metal sheets 35 are stacked together, and the strength of the expansion rubber tube 3 is further enhanced by providing the plural stacked elastic metal sheets 35.

In this embodiment, the elastic metal sheet 35 may also be a sheet metal sheet, and the sheet metal sheet 35 is located between the inner rubber sleeve 33 and the outer rubber sleeve 34 to support the inner rubber sleeve 33 and the outer rubber sleeve 34 to form a framework of the expanding rubber sleeve 3, so as to enhance the strength of the expanding rubber sleeve 3. The skeleton formed by the sheet-shaped elastic metal sheets 3 may be a plurality of sheet-shaped elastic metal sheets 3 stacked one on another to further enhance the strength of the expansion rubber sleeve 3.

When a plurality of the sheet-shaped elastic metal sheets 35 are provided, the plurality of sheet-shaped elastic metal sheets 35 may be circumferentially arranged between the inner rubber cylinder 33 and the outer rubber cylinder 34 at intervals. Namely, the plurality of elastic metal sheets 35 are circumferentially arranged at intervals, so that the inner rubber sleeve 33 and the outer rubber sleeve 34 can be supported at all positions in the circumferential direction of the expansion rubber sleeve 3, and the strength of the expansion rubber sleeve 3 is enhanced.

The following briefly introduces the use process of the external casing packer provided by the embodiment of the present invention.

Firstly, removing the agent injection port 210 of the sleeve outer packer and the plugging head 6 on the exhaust port 50; then, injecting a packing medium into the second annular space 13 from the injection port 210, wherein the filling amount of the packing medium can be determined according to the volume of the expansion rubber sleeve 3 to be expanded and the ratio of the clean water to the packing medium to be injected into the expansion rubber sleeve 3, for example, the ratio of the clean water to the packing medium can be 4:1 or 3: 1; next, the plugging head 6 is mounted on the injection port 210 and the exhaust port 50; then, according to the position required by design, connecting the casing outer packer with an oil layer casing and other downhole tools in series and running into the well; adding clean water into the well from the casing for pressurizing, wherein the clean water enters the working cavity 26 through the liquid inlet hole 11 of the central pipe 1, pushing the releasing piston 25 to cut the shear pin 7 to move upwards, so that the flow channel 231 of the valve body mounting seat 22 is opened, the clean water passes through the flow channel 231 and acts on the conical surface of the valve core 235 of the one-way liquid inlet valve 23 by virtue of water pressure, the valve core 235 moves downwards, pushing the spring 236 to contract, the liquid outlet 233 is opened, the clean water enters the expansion rubber cylinder 3 through the liquid outlet 233, the clean water reacts with a packing medium in the expansion rubber cylinder 3 and is solidified, so as to realize permanent and effective packing of a stratum, and the clean water radially expands the elastic metal sheet 35, the inner rubber cylinder 33 and the outer rubber cylinder 34 and prompts the second rubber cylinder joint 32 to carry the rubber cylinder connecting sleeve 5 to move upwards along the central pipe 1 until the expansion rubber cylinder 3; after the sealing is finished, the filling of clear water and pressurization are stopped, the spring 236 of the one-way liquid inlet valve 23 is reset to push the valve core 235 to move upwards, the conical surface of the valve core 235 is sealed with the annular sealing gasket 237 to seal the liquid inlet 232, and the clear water in the inner cavity of the rubber cylinder is prevented from overflowing when the rubber cylinder is expanded.

The above description is only an optional embodiment of the present invention, and is not intended to limit the present invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included within the protection scope of the present invention.

Claims

1. An external casing packer, comprising:

the pipe wall of the central pipe (1) is provided with a liquid inlet hole (11) communicated with the inner cavity of the central pipe (1);

the installation cylinder (2) is coaxially sleeved outside the central pipe (1), one end of the installation cylinder (2) is in sealing fit with the central pipe (1), and a first annular space (12) communicated with the liquid inlet hole (11) is formed between the installation cylinder (2) and the central pipe (1);

the expansion rubber cylinder (3) is coaxially sleeved outside the central tube (1), one end of the expansion rubber cylinder (3) is connected with the other end of the mounting tube (2), the other end of the expansion rubber cylinder (3) is in sealing fit with the central tube (1), a second annular space (13) is arranged between the expansion rubber cylinder (3) and the central tube (1), and the first annular space (12) is communicated with the second annular space (13);

an insulating medium filled in the second annular space (13), the insulating medium being configured to react with water to produce a solidified substance.

2. The external casing packer of claim 1, wherein the packing medium is an acrylamide material chemical plugging agent.

3. The external casing packer according to claim 1, characterized in that the expanding packer (3) comprises: a first rubber cylinder joint (31), a second rubber cylinder joint (32), an inner rubber cylinder (33), an outer rubber cylinder (34) and an elastic metal sheet (35) which are coaxially sleeved on the central tube (1),

the one end that first packing element connects (31) with the other end of installation section of thick bamboo (2) is connected, the other end that first packing element connects (31) with the one end of outer packing element (34) is connected, outer packing element (34) cover is established on interior packing element (33), relative both sides face on elastic metal piece (35) respectively with the inner wall of outer packing element (34) with the outer wall laminating of interior packing element (33) is connected, the other end of outer packing element (34) with the one end that second packing element connects (32) is connected, the outer wall of the one end of interior packing element (33) with the inner wall connection of first packing element connects (31), the other end of interior packing element (33) with the inner wall connection of second packing element connects (32), the other end that second packing element connects (32) with center tube (1) sealing fit.

4. The external casing packer according to claim 1, further comprising a one-way liquid inlet valve (23), the one-way liquid inlet valve (23) being located within the first annular space (12),

the liquid inlet (232) of the one-way liquid inlet valve (23) is communicated with the first annular space (12), and the liquid outlet (233) of the one-way liquid inlet valve (23) is communicated with the second annular space (13).

5. The external casing packer according to claim 4, wherein the mounting cylinder (2) comprises a valve body mounting seat (22), the valve body mounting seat (22) is coaxially sleeved outside the central pipe (1), the valve body mounting seat (22) is in sealing fit with the central pipe (1), the valve body mounting seat (22) partitions the first annular space (12), a flow passage (231) which penetrates through the valve body mounting seat (22) in the axial direction of the central pipe (1) is arranged on the valve body mounting seat (22), and the flow passage (231) is communicated with a liquid inlet (232) of the one-way liquid inlet valve (23).

6. The casing external packer according to claim 4, wherein the one-way liquid inlet valve (23) is provided in plurality, and the one-way liquid inlet valve (23) is arranged in a circumferential direction at intervals.

7. The outside-of-pipe packer as recited in claim 4, wherein the one-way liquid inlet valve (23) comprises a valve sleeve (234), a valve core (235) and a spring (236), the valve core (235) is arranged in the valve sleeve (234) in a sliding manner along the axial direction of the valve sleeve (234), an annular sealing gasket (237) is inserted into one end of the valve sleeve (234), the inner diameter of the annular sealing gasket (237) is smaller than the outer diameter of the valve core (235), one end of the spring (236) abuts against the valve core (235), and the other end of the spring (236) abuts against a stopping structure on the inner wall of the valve sleeve (234).

8. The external casing packer according to claim 4, further comprising a release piston (25), the release piston (25) being slidably arranged in the first annular space (12), the release piston (25) blocking an inlet port (232) of the one-way inlet valve (23),

a working cavity (26) communicated with the liquid inlet hole (11) is arranged between the releasing piston (25) and the central pipe (1), the releasing piston (25) is fixed on the mounting cylinder (2) through a shear pin (7), and the releasing piston (25) can move under the action of liquid pressure in the working cavity (26) so that a liquid inlet (232) of the one-way liquid inlet valve (23) is communicated with the liquid inlet hole (11).

9. The excluder of any one of claims 1 to 8, further comprising a first pipe coupling (27) and a second pipe coupling (28), an outer wall of one end of said first pipe coupling (27) being threadedly connected to one end of said mounting cylinder (2), an inner wall of one end of said first pipe coupling (27) being threadedly connected to one end of said center pipe (1), and an inner wall of one end of said second pipe coupling (28) being threadedly connected to the other end of said center pipe (1).

10. The packer of any one of claims 1 to 8, wherein the mounting cylinder (2) is provided with an injection port (210) communicated with the first annular space (12), a plugging head (6) is inserted into the injection port (210), the other end of the expansion rubber cylinder (3) is provided with an exhaust port (50), and the plugging head (6) is inserted into the exhaust port (50).