Inflatable packer-plug for oil well tubing

Abstract

FIELD: oil-well tubing.SUBSTANCE: invention relates to an inflatable packer-plug for oil well tubing. The inflatable packer-plug for tubing includes a mechanism for one-way seating and depressurization, a mechanism for anchoring and sealing, a guide mechanism to prevent premature seating and the main part of the rubber cylinder. The lower end of the one-way seating and depressurization mechanism is connected to the coupling of the upper part of the anchoring and sealing mechanism by means of a two-way element. The main part of the rubber cylinder is mounted on the mandrel of the anchoring and sealing mechanism. The lower end of the upper part coupling is connected by threads to the coupling head of the main part of the rubber cylinder. The mandrel is inserted into the guide mechanism to prevent premature seating. The guide mechanism to prevent premature seating is connected to the main part of the rubber cylinder via a lower part coupling. The mandrel is threaded to the guide head in the guide mechanism to prevent premature seating. The one-way seating and release mechanism consists of a catch neck, a one-way piston, a spring, an end cap, a connector, and a two-way element. The fishing neck is a cavity structure, the single-action piston is installed in the adapter inside the catch neck, and the lower end of the one-way piston is connected to the spring. The upper end of the connector is mated by threads to the catch neck and compresses the spring, and the spring is located in the hollow cavity of the catch neck. The end cap is mounted on the catch neck, and the lower end of the end cap is connected by threads to the upper end of the two-way element.EFFECT: increasing the efficiency of the device.6 cl, 8 dwg

Description

Field of technology

[0001] The present invention relates to the technical field of tools for repairing wells in oil and gas fields, in particular to an inflatable packer-plug for tubing, a tool and a method for lowering it. Prior art

[0002] The plug packer is used for inter-layer isolation in oil and gas wells, and the anchoring and sealing element of the plug packer is a rubber cylinder made of elastic rubber to isolate liquid and pressure. The plug packer is widely used in the oil and gas development process, mainly: temporary or permanent isolation of productive formations, isolation of aquifers, temporary plugging during well workover, extrusion, using as a temporary production packer in calculating the production volume, well abandonment, acidification of selected formations to increase the flow rate, descaling of selected formations, searching for productive formations with effluent, testing of selected formations, testing of casing and tubing for leak testing, permanent or temporary isolation of productive formations, isolation of aquifers, using temporary bridge plug for well workover / wellhead replacement, choke the bottom of the well,retrievable span insulation, insulation of intermediate productive formations with effluent, insulation of leaking tubing and casing, insulation of damaged pipes for protection against sand, subsequent gravel packing, depth control marking for lateral drilling or perforation, etc.,

[0003] In order to achieve good sealing, the commonly used packer plug has a small gap between the outer diameter and the inner diameter of the casing, but in many situations, the packer plug must pass through narrow spaces such as tubing, valves and nozzles, and it is required to seal large spaces of the wellbore. For example: sealing the casing through the tubing, plugging, retrieving the packer plug with a steel wire or a continuous pipe after the operation is completed; the above process is not possible when using a conventional packer plug. The following packer plug designs are known from the prior art: US2004216871A1, published 04.11.2004, RU180899U1, published 29.06.2018, CN106761538A, published 31.05.2017.Summary of the invention

[0004] Taking into account the shortcomings of the prior art, the object of the present invention is to provide an inflatable tubing plug packer, a tool and a running method thereof, which have features such as simple structure and ease of use, to alleviate the problems that the plug packer is difficult to pass through narrow spaces, difficult to reliably isolate large spaces and difficult to retrieve.

[0005] In order to achieve the above object, the present invention provides the following solution: an inflatable packer plug for tubing, including a mechanism for one-way landing and depressurization and a mechanism for anchoring and sealing, wherein the mechanism for one-way landing and depressurization is connected to the mechanism for anchoring and sealing;The inflatable packer plug for tubing further includes a guide mechanism for preventing premature landing and a main part of the rubber cylinder, wherein the lower end of the mechanism for one-sided landing and depressurization is connected to the coupling of the upper part of the mechanism for anchoring and sealing by means of a two-way element, the main part of the rubber cylinder is mounted on the mandrel I of the mechanism for anchoring and sealing, the lower end of the coupling of the upper part is connected by threads to the connecting head of the main part of the rubber cylinder, and the mandrel I is inserted into the guide mechanism for preventing premature landing, wherein the guide mechanism for preventing premature landing is connected to the main part of the rubber cylinder by means of the coupling of the lower part, the mandrel I is connected by threads to the guide head in the guide mechanism for preventing premature landing.

[0006] Next, the mechanism for one-sided seating and depressurization includes a fishing neck, a single-action piston, a spring, an end cap, a connector and a two-way element, wherein the fishing neck is a cavity structure, the single-action piston is installed in an adapter inside the fishing neck, and the lower end of the single-action piston is connected to the spring, wherein the upper end of the connector is connected by threads to the fishing neck and compresses the spring, and the spring is located in the hollow cavity of the fishing neck, the end cap is installed on the fishing neck, and the lower end of the end cap is connected by threads to the upper end of the two-way element.

[0007] Furthermore, the single-acting seating and depressurization mechanism further includes a vulcanized rubber, a lock screw, and a depressurization pin, wherein the vulcanized rubber is vulcanized in the groove of the single-acting piston, and the vulcanized rubber has a "concave" shape; the catch neck is equipped with four lock screws, and one end of the connector is inserted into the two-way element and is limited in movement by the depressurization pin.

[0008] Next, the single-acting piston is equipped with one liquid supply landing channel, the fishing neck is equipped with one pressure relief hole, the connector is equipped with one pressure transmission hole, and the two-way element is equipped with one pressure transmission channel I.

[0009] Next, the anchoring and sealing mechanism includes a mandrel I and an upper part coupling, wherein one end of the mandrel I is connected by threads to the inner part of the two-way member; the main part of the rubber cylinder includes an outer upper rubber cylinder, a laminated steel sheet, an outer middle rubber cylinder, an inner rubber cylinder, an outer lower rubber cylinder and two connecting heads; the two connecting heads are vulcanized together with the outer upper rubber cylinder and the outer lower rubber cylinder, respectively, the upper end of the upper part coupling is connected by threads to the lower end of the two-way member, and the lower end of the upper part coupling is connected by threads to the outer upper rubber cylinder by means of the connecting head.

[0010] Next, the inner rubber cylinder is mounted on the mandrel I, the laminated steel sheet is fixed to the outer wall of the inner rubber cylinder, and the outer upper rubber cylinder, the outer middle rubber cylinder and the outer lower rubber cylinder are mounted from top to bottom on the inner rubber cylinder and the outer side of the laminated steel sheet, wherein the annular space between the lower end of the two-way member and the mandrel I is a pressure transmission channel Ⅱ, and is also the outlet of the pressure transmission channel I; a pressure relief channel is formed between the inner rubber cylinder and the mandrel I, and an upper and lower balancing channel is located inside the mandrel I.

[0011] Next, the guide mechanism for preventing premature landing includes a lower part coupling, an O-shaped thrust ring, a shear seat, a shear ring, a guide head and a shear pin I, wherein the upper end of the lower part coupling is mounted on the main body of the rubber cylinder by a threaded connection with a coupling head vulcanized on the outer lower rubber cylinder, and the lower end of the lower part coupling is connected by threads with the shear seat; the O-shaped thrust ring is located inside the shear seat, the shear ring is mounted on the mandrel I and fixed on the shear seat by the shear pin I, the mandrel I passes through the lower part coupling, the O-shaped thrust ring, the shear seat and the shear ring, and the end of the mandrel I is inserted into the guide head and connected by threads with the guide head.

[0012] Based on the inflatable packer plug for tubing, the present invention also provides a running tool for the inflatable packer plug for tubing, the running tool including an upper coupling, a limiting half ring, a hinge cylinder, a hinge coupling, an outer cylinder, a ball seat, a piston, a spring grip, a mandrel II, a lower end cover, a socket head cap screw and a shear pin II, the hinge cylinder being mounted on the hinge coupling, the upper end of the hinge cylinder being threaded to the upper coupling, and the lower end of the hinge cylinder being threaded to the outer cylinder; the limiting half ring being installed in the groove of the upper end of the hinge coupling, the ball seat being located inside the hinge coupling, the spring grip being threaded to the mandrel II;the piston is mounted on a spring clamp and limited in movement by means of a hexagon socket head screw and a cylindrical head, and fixed by means of a shear pin II; the upper end of the mandrel II is connected to the hinge coupling, and the lower end of the mandrel II is connected to the lower end cover.

[0013] Next, the limiting half ring is two semicircles, and the limiting half ring is installed in the groove of the articulated coupling, and its remaining space is a movable space; the articulated coupling is equipped with four pressure distribution holes, the annular space formed between the articulated coupling and the outer cylinder is an annular space for transmitting pressure; the piston is equipped with a limiting groove and a release groove, and the spring claw is equipped with a hole for the limiting screw and a claw head.

[0014] The present invention relates to a method of running an inflatable tubing plug packer, based on an inflatable tubing plug packer and a running tool thereof, the running method specifically includes the following process:a. Running state: the fishing neck of the packer is fixed inside the running tool, and the running tool and the packer components are in their original positions;b. Landing state: in the seat landing state, there is pressurized fluid filled in advance before entering the well above the single-action piston, after the inflatable tubing plug packer and the running tool thereof are lowered to the design positions, the pressurized fluid enters the inside of the packer under the action of nitrogen;when the pressure above the single-acting piston exceeds the spring force, the single-acting piston is pushed downward until the liquid supply landing port opens, and the pressure is transmitted through the liquid supply landing port, then through the pressure relief hole and the pressure transmitting hole to the pressure transmitting port I, and finally to the pressure transmitting port II; after the shear pin I is sheared, under the action of the radial tensile force in the inner rubber cylinder generated under the pressure, if the pressure continues to increase, the inner rubber cylinder will expand and deform until the outer upper rubber cylinder, the outer middle rubber cylinder and the outer lower rubber cylinder contact the casing wall, thereby completing the anchoring and sealing, and dividing the casing into an upper space and a lower space;c. Release state: the pressure continues to rise in the seating state, the pressure is transmitted to the pressure transmission annulus through the pressure spreading hole to push the piston downward until the shear pin II is cut off, then the piston continues to move downward to the release groove and is above the grip head, then the spring grip is released from the compressed state and loosens the fishing neck, while it is raised upward to leave the packer in the well; d. Depressurization state: lower the fishing tool to the fishing neck and lift it up, while the fishing tool drives the connector to cut the depressurization pin, then continue to lift it upward to the pressure relief hole and above the end cap; at this time, the pressure inside the inner rubber cylinder is released, and the inner rubber cylinder recedes due to the loss of pressure to complete the depressurization.

[0015] The advantages of using the technical solution according to the present invention are as follows: 1. The inflatable tubing plug packer and its running tool according to the present invention are suitable for underground well workover, layer testing, and temporary isolation, and can be run from the tubing and installed in the casing. Therefore, retrieving the tubing is not required, greatly simplifying the work. The use of the inflatable tubing plug packer can shorten the work process and ensure accurate sealing position, improving efficiency and saving costs.

[0016] 2. The inflatable tubing plug packer according to the present invention consists of a one-way setting and depressurization mechanism, an anchoring and sealing mechanism and a premature setting prevention guide mechanism, and the running tool is used in combination with the inflatable tubing plug packer; the one-way setting and depressurization mechanism consists of a fishing neck, a one-way valve, a spring, an end cap, a connector and a two-way member; the anchoring and sealing mechanism uses a combined structure of two-layer rubber and laminated steel sheet, including the inner part is long rubber, the intermediate part is laminated steel sheet, and the outer part is three-section vulcanized rubber; the premature setting prevention guide mechanism consists of a lower part coupling, a shear ring, a shear seat and a guide head;The running tool consists of an upper sleeve, a limiting half-ring, a hinge cylinder, a hinge sleeve, a ball seat, a mandrel, a piston, a spring grip, an outer cylinder, and a lower end cap. This packer has a small outside diameter but can be installed inside a casing string with a large inside diameter. The packer also features convenient, reliable setting and release functions, reducing risk, cost, and complexity. Drawing description;

[0017] In order to more clearly illustrate the technical solutions in the present invention or technology, the following will briefly introduce the accompanying drawings, which will be used in describing the embodiments or the prior art, and it is obvious that the following accompanying drawings are only the present invention, and for a person skilled in the art, other accompanying drawings can be obtained in accordance with these drawings without applying creative work.

[0018] Fig. 1 is a sectional view of an inflatable plug packer for tubing according to the present invention; Fig. 2 is a sectional view of a mechanism for one-way setting and depressurization of the packer according to the present invention; Fig. 3 is a sectional view of a mechanism for anchoring and sealing the packer according to the present invention; Fig. 4 is a sectional view of a guide mechanism for preventing premature setting of the packer according to the present invention; Fig. 5 is a structural diagram of a two-way element according to the present invention; Fig. 6 is a sectional view of a running tool according to the present invention; Fig. 7 is a structural diagram of a piston according to the present invention; Fig. 8 is a structural diagram of a spring grip according to the present invention.

[0019] Legend in the figure: 1. Mechanism for one-sided landing and depressurization; 101. Fishing neck; 102. Single-acting piston; 103. Spring; 104. End cap; 105. Connector; 106. Two-way element; 1061. Channel for transmitting pressure I; 107. Vulcanized rubber; 108. Lock screw; 109. Depressurization pin; 1001. Landing channel for supplying liquid; 1002. Hole for relieving pressure; 1003. Hole for transmitting pressure; 2. Mechanism for anchoring and sealing; 201. Mandrel I; 202. Upper part coupling; 203. Outer upper rubber cylinder; 204. Laminated steel sheet; 205. Outer middle rubber cylinder; 206. Inner rubber cylinder; 207. Outer lower rubber cylinder; 2001. Pressure transmission channel II; 2002. Pressure relief channel; 2003. Upper and lower balancing channel; 3. Guide mechanism to prevent premature landing; 301. Lower part coupling; 302. O-shaped thrust ring; 303. Shear seat; 304.Shear ring; 305. Guide head; 306. Shear pin I; 3001. Adapter; 401. Upper sleeve; 402. Limit half ring; 403. Hinged cylinder; 404. Hinged sleeve; 405. Outer cylinder; 406. Ball seat; 407. Piston; 408. Spring grip; 409. Mandrel II; 410. Lower end cover; 411. Socket head cap screw; 412. Shear pin II; 4001. Sliding space; 4002. Pressure distribution hole; 4003. Annular space for pressure transmission; 4071. Limit groove; 4072. Discharge groove; 4081. Hole for limit screw; 4082. Gripping head. Specific embodiments.

[0020] In order to more clearly illustrate the purpose, technical solutions and advantages of the present invention, the present invention is described in detail below in combination with specific embodiments.

[0021] It should be noted that, unless otherwise defined, technical terms or scientific terms used in the present invention have the ordinary meaning understood by those of ordinary skill in the field to which the present invention pertains. The terms "first," "second," and similar words used in the present invention do not denote any order, quantity, or importance, but are used only to distinguish between the various components. The term "includes" or "contains" and similar words mean that the elements or objects appearing before this word cover the elements or objects and their equivalents listed after this word, but not excluding other elements or objects. The term "connected" or "connected" and similar words are not limited to physical or mechanical connections, but may include an electrical connection, direct or indirect. The words "up," "down," "left," "right," etc.are used only to explain relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship can be altered.

[0022] As shown in Fig. 1-8, the inflatable packer-plug for tubing includes a mechanism for one-sided landing and depressurization 1, a mechanism for anchoring and compacting 2, a guide mechanism for preventing early landing 3 and a main part of the rubber cylinder, wherein the lower end of the mechanism for one-sided landing and depressurization 1 is connected to the coupling of the upper part 202 of the mechanism for anchoring and compacting 2 by means of a two-way element 106, the main part of the rubber cylinder is mounted on the mandrel I 201 of the mechanism for anchoring and compacting 2, the lower end of the coupling of the upper part 202 is connected by threads to the connecting head of the main part of the rubber cylinder, and the mandrel I 201 is inserted into the guide mechanism for preventing early landing 3, wherein the guide mechanism for preventing early landing 3 is connected to the main part of the rubber cylinder by means of the coupling of the lower part 301,The mandrel I 201 is threadedly connected to the guide head 305 in the guide mechanism for preventing premature landing 3. The inflatable packer-plug for tubing according to the present invention consists of a mechanism for one-sided landing and depressurization, a mechanism for anchoring and sealing and a guide mechanism for preventing premature landing, and the running tool is used in combination with the inflatable packer-plug for tubing; this packer has a small outer diameter, but can be installed inside the casing with a large inner diameter, and the packer has convenient and reliable functions of landing and depressurization, which reduces the risk, cost and difficulty of the work.

[0023] The one-way landing and depressurization mechanism 1 includes a fishing neck 101, a single-action piston 102, a spring 103, an end cap 104, a connector 105 and a two-way element 106, wherein the fishing neck 101 is a cavity structure, the single-action piston 102 is installed in an adapter inside the fishing neck 101, and the lower end of the single-action piston 102 is connected to the spring 103, wherein the upper end of the connector 105 is connected by threads to the fishing neck 101 and compresses the spring 103, and the spring 103 is located in the hollow cavity of the fishing neck 101, the end cap 104 is installed on the fishing neck 101, and the lower end of the end cap 104 is connected by threads to the upper end of the two-way element 106.

[0024] The one-way seating and depressurization mechanism 1 further includes a vulcanized rubber 107, a lock screw 108 and a depressurization pin 109, wherein the vulcanized rubber 107 is vulcanized in the groove of the single-action piston 102, and the vulcanized rubber 107 has a “concave” shape with an intermediate groove that allows deformation; The fishing neck 101 is equipped with four locking screws 108, and one end of the connector 105 is inserted inside the two-way element 106 and is limited in movement by means of a depressurization pin 109. The single-action piston 102 is equipped with one landing channel for supplying liquid 1001, the fishing neck 101 is equipped with one hole for pressure relief 1002, the connector 105 is equipped with one hole for transmitting pressure 1003, and the two-way element 106 is equipped with one channel for transmitting pressure I 1061.

[0025] The anchoring and sealing mechanism 2 includes a mandrel I 201 and an upper part coupling 202, wherein one end of the mandrel I 201 is connected by threads to the inner part of the two-way member 106; the rubber cylinder main part includes an outer upper rubber cylinder 203, a laminated steel sheet 204, an outer middle rubber cylinder 205, an inner rubber cylinder 206, an outer lower rubber cylinder 207 and two connecting heads; two coupling heads are vulcanized together with the outer upper rubber cylinder 203 and the outer lower rubber cylinder 207, respectively, the upper end of the coupling of the upper part 202 is connected by threads to the lower end of the two-way element 106, and the lower end of the coupling of the upper part 202 is connected by threads to the outer upper rubber cylinder 203 using the coupling head.The inner rubber cylinder 206 is mounted on the mandrel I 201, the laminated steel sheet 204 is attached to the outer wall of the inner rubber cylinder 206, and the outer upper rubber cylinder 203, the outer middle rubber cylinder 205 and the outer lower rubber cylinder 207 are mounted from top to bottom on the inner rubber cylinder 206 and the outer side of the laminated steel sheet 204, wherein the annular space between the lower end of the two-way element 106 and the mandrel I 201 is a channel for transmitting pressure II 2001, and is also the outlet of the channel for transmitting pressure I 1061; The pressure relief channel 2002 is formed between the inner rubber cylinder 206 and the mandrel I 201, and the upper and lower balancing channel 2003 is located inside the mandrel I 201. There are three anchoring and sealing points: the outer upper rubber cylinder 203, the outer middle rubber cylinder 205, and the outer lower rubber cylinder 207.

[0026] The guide mechanism for preventing premature landing 3 includes a lower part coupling 301, an O-shaped thrust ring 302, a shear seat 303, a shear ring 304, a guide head 305 and a shear pin I 306, wherein the upper end of the lower part coupling 301 is installed on the main part of the rubber cylinder by a threaded connection with the coupling head vulcanized on the outer lower rubber cylinder 207, and the lower end of the lower part coupling 301 is connected by threads with the shear seat 303; The O-shaped thrust ring 302 is located inside the shear seat 303, the shear ring 304 is mounted on the mandrel I 201 and secured on the shear seat 303 with the help of the shear pin I 306, the mandrel I 201 passes through the coupling of the lower part 301, the O-shaped thrust ring 302, the shear seat 303 and the shear ring 304, and the end of the mandrel I 201 is inserted into the guide head 305 and is connected by threads with the guide head 305.Since the inner diameter of the shear ring 304 in the guide mechanism for preventing premature landing 3 is smaller than the outer diameter of the upper portion of the adapter 3001, the shear ring 304 cannot move upward; when the tensile force at which the radial deformation of the inner rubber cylinder 206 occurs, caused by the pressure in the pressure relief channel 2002, is less than the shear force of the shear pin I 306, the inner rubber cylinder 206 will not be radially deformed, and the landing action will not occur.

[0027] The single-action landing and depressurization mechanism 1 has the function of preventing premature landing, and when the pressure is less than the force of the spring 103, the single-action piston 102 will not move downward, while the single-action piston 102 still seals the lower space, the pressure will not be transmitted to the lower rubber cylinder, and the landing action will not occur. When the single-acting landing and depressurization mechanism 1 is in the landing state, the external pressure exceeds the force of the spring 103, the single-acting piston 102 will move downward until the vulcanized rubber 107 leaves the sealing surface, whereby the external pressure is transmitted to the packer through the landing channel for supplying liquid 1001, and finally to the pressure relief channel 2002 through the pressure transmission channel I 1061 along the pressure relief hole 1002 and the pressure transmission hole 1003.

[0028] When the inner rubber cylinder 206 inside the anchoring and sealing mechanism 2 is subjected to a shear force greater than the force of the shear pin I 306, the shear pin I 306 is sheared, the lower part sleeve 301 and the shear seat 303 can move upward, and the inner rubber cylinder 206 can be deformed in the radial and transverse directions until the outer upper rubber cylinder 203, the outer middle rubber cylinder 205 and the outer lower rubber cylinder 207 contact the casing wall, thereby fixing it in the design position and sealing it as two separate spaces.

[0029] When the one-way seating and depressurization mechanism 1 is in the depressurization state, the catching neck 101 is caught by the catching tool, lifted upward until the depressurization pin 109 is cut off, and the pressure release hole 1002 moves above the end cap 104, thereby restoring the inner rubber cylinder 206 to its original position to complete the depressurization.

[0030] The present invention also provides a tool for running an inflatable packer-plug for tubing, including an upper coupling 401, a limiting half ring 402, a hinge cylinder 403, a hinge coupling 404, an outer cylinder 405, a ball seat 406, a piston 407, a spring grip 408, a mandrel II 409, a lower end cover 410, a socket head cap screw 411 and a shear pin II 412, wherein the hinge cylinder 403 is mounted on the hinge coupling 404, the upper end of the hinge cylinder 403 is connected by threads to the upper coupling 401, and the lower end of the hinge cylinder 403 is connected by threads to the outer cylinder 405; the limiting half ring 402 is installed in the groove of the upper end of the hinge coupling 404, the ball seat 406 is located inside the hinge coupling 404, the spring clamp 408 is connected by threads to the mandrel II 409;the piston 407 is mounted on the spring grip 408 and limited in movement by means of the screw with the internal Allen key and the cylindrical head 411, and fixed by means of the shear pin II 412; the upper end of the mandrel II 409 is connected to the articulated coupling 404, and the lower end of the mandrel II 409 is connected to the lower end cover 410. The limiting half ring 402 is two semicircles, and the limiting half ring 402 is mounted in the groove of the articulated coupling 404, and its remaining space is the movable space 4001; the articulated coupling 404 is equipped with four holes for distributing pressure 4002, the annular space formed between the articulated coupling 404 and the outer cylinder 405 is the annular space for transmitting pressure 4003; piston 407 is equipped with a limiting groove 4071 and an exhaust groove 4072, and spring grip 408 is equipped with a hole 4081 for a limiting screw and a head 4082 of the grip.;

[0031] The hole for the limit screw 4081 and the gripper head 4082 are in the same plane; one end of the socket head cap screw 411 is installed in the hole for the limit screw 4081, and the other end is installed in the limit groove 4071, thereby ensuring that the release groove 4072 and the gripper head 4082 are in the same plane. The gripper head 4082 is initially compressed on the front end of the release groove 4072, after the shear pin II 412 is sheared, the release groove 4072 moves over the gripper head 4082, and the gripper head 4082 comes out of the compressed state, thereby unlocking the packer.

[0032] The inflatable tubing plug packer according to the present invention consists of a one-way setting and depressurization mechanism, an anchoring and sealing mechanism, and a premature setting prevention guide mechanism, and the running tool is used in combination with the inflatable tubing plug packer; the one-way setting and depressurization mechanism consists of a fishing neck, a one-way valve, a spring, an end cap, a connector and a two-way member; the anchoring and sealing mechanism uses a combined structure of two-layer rubber and laminated steel sheet, including the inner part is long rubber, the intermediate part is laminated steel sheet, and the outer part is three-section vulcanized rubber; the premature setting prevention guide mechanism consists of a lower part coupling, a shear ring, a shear seat and a guide head;The running tool consists of an upper collar, a limiting half-ring, a hinge cylinder, a hinge sleeve, a ball seat, a mandrel, a piston, a spring grip, an outer cylinder, and a lower end cap. This packer has a small outside diameter but can be installed inside casing with a large inside diameter. The packer also features convenient, reliable seating and release functions, reducing risk, cost, and complexity. The packer has a maximum outside diameter of 2.125 inches and can pass through 2.875-inch tubing.

[0033] The present invention also provides a method for running an inflatable tubing plug packer, which includes the following process:a. Running state: the fishing neck 101 of the packer is fixed inside the running tool, and the running tool and the packer components are in the original positions;b. Landing state: in the seat landing state, there is pressurized fluid filled in advance before entering the well above the single-action piston 102, after the inflatable tubing plug packer and its running tool are lowered to the design positions, the pressurized fluid enters the inside of the packer under the action of nitrogen;when the pressure above the single-action piston 102 exceeds the force of the spring 103, the single-action piston 102 is pushed downward until the liquid supply landing channel 1001 opens, whereby the pressure is transmitted through the liquid supply landing channel 1001, then through the pressure relief hole 1002 and the pressure transmission hole 1003 into the pressure transmission channel I 1061, and finally into the pressure transmission channel II 2001; after the shear pin I 306 is sheared under the action of the radial tensile force in the inner rubber cylinder 206 generated under pressure, if the pressure continues to increase, the inner rubber cylinder 206 will expand and deform until the outer upper rubber cylinder 203, the outer middle rubber cylinder 205 and the outer lower rubber cylinder 207 contact the wall of the casing, thereby completing the anchoring and sealing, and dividing the casing into an upper space and a lower space;c. Release state: the pressure continues to rise in the seated state, the pressure is transmitted to the pressure transmission annulus 4003 through the pressure distribution hole 4002 to push the piston 407 downward until the shear pin II 412 is cut off, then the piston 407 continues to move downward until the release groove 4072 and is above the grip head 4082, then the spring grip 408 comes out of the compressed state and loosens the fishing neck 101, while it is raised upward to leave the packer in the well; d. Depressurization state: the fishing tool is lowered to the fishing neck 101 and raised upward, while the fishing tool drives the connector 105 to cut the depressurization pin 109, then continue to raise it upward until the pressure relief hole 1002 and above the end cap 104;at this time, the pressure inside the inner rubber cylinder 206 is released, and the inner rubber cylinder 206 retreats due to the loss of pressure to complete the depressurization.;

[0034] It should be noted that due to the different pressure required to cut each pin, the corresponding process can be controlled by applying different pressure during use.

[0035] The inflatable tubing plug packer and its running tool according to the present invention are suitable for underground well workovers, layer testing, and temporary isolation. They can be run from the tubing and installed in the casing. Therefore, retrieving the tubing is not required, greatly simplifying the work. Using the inflatable tubing plug packer can shorten the work process and ensure precise sealing, improving efficiency and saving costs.

[0036] The combined structure inside the anchoring and sealing mechanism according to the present invention: a combined structure of an inner rubber cylinder, three outer rubber cylinders and a laminated steel sheet is adopted, wherein the laminated steel sheet provides high-strength support, the inner rubber cylinder provides a high expansion coefficient, and the three outer rubber cylinders ensure the reliability of the anchoring and sealing functions.

[0037] The one-way setting and depressurization mechanism and the early setting prevention guide mechanism according to the present invention have a premature setting prevention function to avoid setting the packer before the packer reaches a predetermined position during its lowering; and the depressurization mechanism inside the one-way setting and depressurization mechanism only lifts and cuts the pin to achieve reliable depressurization; furthermore, the lowering tool only continues to apply pressure after the packer is set to complete the release action.

[0038] Those skilled in the art should understand that the embodiments are only schematic and do not imply that the scope of the present invention is limited to these examples; based on the ideas of the present invention, combinations between the above embodiments or technical characteristics in various embodiments are also possible, the execution steps can be implemented in any order, and there are many other variations of various aspects of the present invention, and the variants that are for the sake of brevity are not described in detail.

[0039] The present invention is intended to cover all such alternatives, modifications, and variations that fall within the broad scope of the appended claims. Therefore, within the meaning and principle of the present invention, any omissions, modifications, equivalent alternatives, or modernizations, etc., shall be included within the scope of protection of the present invention.

Claims

1. An inflatable packer plug for tubing, comprising a mechanism for one-sided landing and depressurization (1) and a mechanism for anchoring and sealing (2), where the mechanism for one-sided landing and depressurization (1) is connected to the mechanism for anchoring and sealing (2), characterized in that the inflatable packer plug for tubing additionally includes a guide mechanism for preventing premature landing (3) and the main part of the rubber cylinder, wherein the lower end of the mechanism for one-sided landing and depressurization (1) is connected to the coupling of the upper part (202) of the mechanism for anchoring and sealing (2) by means of a two-way element (106), the main part of the rubber cylinder is mounted on a mandrel I (201) of the mechanism for anchoring and sealing (2),the lower end of the coupling of the upper part (202) is connected by threads to the connecting head of the main part of the rubber cylinder and the mandrel I (201) is inserted into the guide mechanism for preventing premature landing (3), wherein the guide mechanism for preventing premature landing (3) is connected to the main part of the rubber cylinder by means of the coupling of the lower part (301), the mandrel I (201) is connected by threads to the guide head (305) in the guide mechanism for preventing premature landing (3); a mechanism for one-sided landing and depressurization (1) includes a fishing neck (101), a single-action piston (102), a spring (103), an end cap (104), a connector (105) and a two-way element (106), wherein the fishing neck (101) is a cavity structure, the single-action piston (102) is installed in an adapter inside the fishing neck (101) and the lower end of the single-action piston (102) is connected to the spring (103),wherein the upper end of the connector (105) is connected by threads to the fishing neck (101) and compresses the spring (103) and the spring (103) is located in the hollow cavity of the fishing neck (101), the end cap (104) is installed on the fishing neck (101) and the lower end of the end cap (104) is connected by threads to the upper end of the two-way element (106)., 2. An inflatable packer-plug for tubing according to claim 1, characterized in that the mechanism for one-sided seating and depressurization (1) additionally includes vulcanized rubber (107), a lock screw (108) and a depressurization pin (109), wherein the vulcanized rubber (107) is vulcanized in the groove of the single-action piston (102) and the vulcanized rubber (107) has a "concave" shape; the fishing neck (101) is equipped with four lock screws (108), and one end of the connector (105) is inserted inside the two-way element (106) and is limited in movement by means of the depressurization pin (109).

3. An inflatable packer-plug for tubing according to claim 2, characterized in that the single-action piston (102) is equipped with one landing channel for feeding liquid (1001), the fishing neck (101) is equipped with one hole for releasing pressure (1002), the connector (105) is equipped with one hole for transmitting pressure (1003), and the two-way element (106) is equipped with one channel for transmitting pressure I (1061).

4. An inflatable packer-plug for tubing according to claim 2, characterized in that the mechanism for anchoring and sealing (2) includes a mandrel I (201) and an upper part coupling (202), wherein one end of the mandrel I (201) is connected by threads to the inner part of the two-way element (106); the main part of the rubber cylinder includes an outer upper rubber cylinder (203), a laminated steel sheet (204), an outer middle rubber cylinder (205), an inner rubber cylinder (206), an outer lower rubber cylinder (207) and two connecting heads; two connecting heads are vulcanized together with the outer upper rubber cylinder (203) and the outer lower rubber cylinder (207), respectively, the upper end of the coupling of the upper part (202) is connected by threads to the lower end of the two-way element (106), and the lower end of the coupling of the upper part (202) is connected by threads to the outer upper rubber cylinder (203) using the connecting head.

5. An inflatable packer-plug for tubing according to claim 4, characterized in that the inner rubber cylinder (206) is mounted on mandrel I (201), the laminated steel sheet (204) is attached to the outer wall of the inner rubber cylinder (206), and the outer upper rubber cylinder (203), the outer middle rubber cylinder (205) and the outer lower rubber cylinder (207) are mounted from top to bottom on the inner rubber cylinder (206) and the outer side of the laminated steel sheet (204), wherein the annular space between the lower end of the two-way element (106) and mandrel I (201) is a channel for transmitting pressure II (2001), and is also the outlet of the channel for transmitting pressure I (1061); a pressure relief channel (2002) is formed between the inner rubber cylinder (206) and the mandrel I (201) and an upper and lower balancing channel (2003) is located inside the mandrel I (201).

6. An inflatable packer-plug for tubing according to claim 5, characterized in that the guide mechanism for preventing premature landing (3) includes a lower part coupling (301), an O-shaped thrust ring (302), a shear seat (303), a shear ring (304), a guide head (305) and a shear pin I (306), wherein the upper end of the lower part coupling (301) is mounted on the main part of the rubber cylinder by means of a threaded connection with a connecting head vulcanized on the outer lower rubber cylinder (207), and the lower end of the lower part coupling (301) is connected by threads to the shear seat (303);The O-shaped thrust ring (302) is located inside the shear seat (303), the shear ring (304) is mounted on the mandrel I (201) and secured on the shear seat (303) with the help of the shear pin I (306), the mandrel I (201) passes through the coupling of the lower part (301), the O-shaped thrust ring (302), the shear seat (303) and the shear ring (304) and the end of the mandrel I (201) is inserted into the guide head (305) and is connected by threads with the guide head (305).;

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