A long-lasting, easy-to-handle, washable well packer and method of using same

Abstract

The application discloses a long-acting and easy-to-handle washable well packer and a use method thereof, and belongs to the technical field of oil and gas well packers. The packer comprises a central pipe, an anchoring and unblocking mechanism, a reverse washing sealing mechanism and a supporting and setting mechanism which are sequentially arranged on the central pipe from top to bottom, and further comprises a back-off safety mechanism which is arranged on the central pipe and located above the anchoring and unblocking mechanism. When the packer fails to be unblocked, the back-off safety mechanism can be used to release the packer, and then a pipe string can be pulled out, and a wellbore treatment tool is used to mill a hydraulic anchor body, so that the risk of downhole accidents is reduced.

Description

Technical Field

[0001] This invention relates to the field of oil well packer technology, specifically to a long-lasting, easy-to-treat washable packer and its usage method. Background Technology

[0002] Low-permeability reservoir water injection wells are characterized by high temperature, high pressure, and easy scaling, resulting in complex downhole conditions. Tubing creep is one of the main causes of stratification tool failure. Currently, bidirectional anchored packers are mainly used in high-pressure deep wells to extend the life of the injection tubing. The Y521 packer, due to its simple setting, anti-creep properties, and resistance to large pressure differentials, is widely used in oilfield water injection, fracturing, and sealing tests, effectively improving tool durability and extending tubing life. However, certain limitations still exist.

[0003] The packer setting track is located outside the lower joint. During the lowering process, the setting mechanism is easily contaminated by well fluid and impurities in the well, which affects the success rate of track reversal during the setting process.

[0004] The hydraulic anchor is controlled by external pressure. When the pressure in the lower casing of the packer is higher than that in the upper casing after setting, the anchor claw extends under pressure and anchors to the inner wall of the casing. If the pressure in the lower casing of the packer is not effectively balanced after injection stops, the anchor claw cannot be retracted, which leads to an increase in the unsealing force of the packer and is prone to downhole accidents such as stuck pipe.

[0005] The pressure in the lower casing of the packer cannot be effectively released. The backwash channel can only be opened after the pressure at both ends of the rubber sleeve is balanced. The opening pressure is high, which poses a great risk of failure of the well washing mechanism. At the same time, the packer needs to overcome the pressure in the lower casing to release the packer, which increases the release force and increases the risk of downhole accidents.

[0006] It cannot be used with the inverted safety connector, and the packer anchoring mechanism after the pipe clamp is difficult to handle.

[0007] Publication (Announcement) No.: CN111594092B discloses a method for using packer backwashing, including: Step 1: Connect the Y221 packer to the tubing string and run it down the well. After the packer is lowered to the predetermined position, lift the tubing string outside the well and rotate the tubing string. Then continue to lower the tubing string to complete the packer setting. Step 2: When backwashing is required, inject fluid into the annulus to increase the casing pressure. When the pressure reaches the set value, push the backwash piston sleeve (105) to compress the backwash spring (102) and move it upward, squeezing the blocking ring (103) to ensure that the backwash mechanism is open. Step 3: When the pressure inside the casing disappears, the backwash piston sleeve (105) returns to its original position under the action of the backwash spring (102), which can close the well washing channel. Step 4: When unsealing is required, lift the tubing string outside the well, and the rubber sleeve (108) resets to complete the unsealing of the packer.

[0008] The existing technology lacks a drop-off mechanism, making it difficult to remove the tubing after a failed unsealing attempt.

[0009] Publication (Announcement) No.: CN112696170B discloses an anchored oil casing safety packer and method, comprising: a high-volume well-washing control device, which is fitted outside the central pipe and connected at its upper end to a first hydraulic control line; and a packer setting, anchoring, and unsealing device, which is fitted outside the central pipe and connected at its upper end to a second hydraulic control line. This prior art can continuously provide setting and anchoring when there is no pressure in the setting hydraulic control line, and can also realize the opening and closing of the high-volume well-washing channel through the well-washing hydraulic control line.

[0010] The existing technology lacks a drop-off mechanism, making it difficult to remove the tubing after a failed unsealing attempt.

[0011] Publication No. CN115992661A discloses a long-lasting anchoring tool and method, including an outer protection mechanism, an inner protection mechanism, a well-washing mechanism, and an anchoring mechanism. The outer protection mechanism includes a connecting sleeve, a protective cylinder, a sealing sleeve, and a starting piston. The inner protection mechanism includes a pressure-transmitting piston, an outer cylinder, and a lower central tube, with a protective fluid placed inside. The well-washing mechanism includes a well-washing sleeve, a well-washing spring, an upper piston, a lower piston, and a sealing element. The anchoring mechanism includes a main body, a spring, anchor claws, and a pressure plate. This invention can effectively improve the service life and retrieval reliability of the anchoring tool, further reducing the risk of subsequent replacement, thereby extending the service life of the supporting tubing string. It is of great significance for further improving the level of fine-scale water injection in the development of old oilfields.

[0012] The existing technology lacks a drop-off mechanism, making it difficult to remove the tubing after a failed unsealing attempt.

[0013] In summary, the technical solutions, technical problems to be solved, and beneficial effects of the above-disclosed technologies are all different from those of the present invention. Regarding the more technical features, technical problems to be solved, and beneficial effects of the present invention, the above-disclosed technical documents do not provide any technical inspiration. Summary of the Invention

[0014] In view of the above-mentioned defects in the existing technology, the purpose of this invention is to provide a long-lasting, easy-to-treat washable packer and its usage method, so as to solve the problems of difficult well washing, difficult unsealing, and difficult treatment of the Y521 packer.

[0015] To achieve the above objectives, the present invention adopts the following technical solution:

[0016] A long-lasting, easy-to-manage washable well packer includes a central tube and, from top to bottom, an anchoring and releasing mechanism, a backwashing and sealing mechanism, and a supporting and setting mechanism, all sequentially arranged on the central tube. It also includes a reverse safety mechanism, which is located on the central tube above the anchoring and releasing mechanism.

[0017] The inverted safety mechanism includes an upper connector, a locking sleeve, a locking block, and a shear pin sleeve;

[0018] The inner wall of the upper end of the central tube is connected to the outer wall of the lower end of the upper connector by a reverse thread, and the locking block passes through the upper end of the central tube and is inserted into the upper connector.

[0019] The central tube has a shear pin sleeve fitted on the outer wall below the upper connector. The shear pin sleeve is connected to the central tube through shear pins. The central tube has a first pressure transmission hole at the corresponding position on the upper end of the shear pin sleeve.

[0020] The outer wall of the clipper sleeve is threaded with a locking sleeve, which covers the locking block. The inner wall of the locking sleeve above the locking block has a receiving groove.

[0021] The anchoring and release mechanism includes hydraulic anchor teeth and hydraulic anchor body;

[0022] The hydraulic anchor body is fitted onto the central tube, and the two ends of the hydraulic anchor teeth are fixed to the outer wall of the hydraulic anchor body. The hydraulic anchor body has through holes in the corresponding areas of the hydraulic anchor teeth.

[0023] A first piston is provided inside the through hole, and a first spring is provided between the first piston and the hydraulic anchor tooth; at least two sets of hydraulic anchor tooth, through hole, first piston, and first spring are provided;

[0024] The central pipe is provided with a pressure groove in the area corresponding to the hydraulic anchor tooth, and a second pressure transmission hole is provided in the pressure groove.

[0025] The hydraulic anchor body has two through holes in the area corresponding to the hydraulic anchor tooth, and the hydraulic anchor tooth is fixed between the two through holes.

[0026] The backwash sealing mechanism includes an inlet sleeve, an upper retaining ring, and a cone.

[0027] The lower end of the hydraulic anchor body is threadedly connected to a water inlet sleeve. A second spring is installed above the annular space between the water inlet sleeve and the central tube. A second piston is installed at the lower end of the second spring.

[0028] The lower end face of the second piston is an outer conical surface. The upper retaining ring is threaded to the inner wall of the lower end of the water inlet sleeve. The upper retaining ring does not contact the central tube. The upper end face of the upper retaining ring is an inner conical surface. The lower end face of the second piston is in contact with the upper end face of the upper retaining ring.

[0029] The water inlet sleeve is provided with a second water inlet hole above the upper end face of the upper baffle ring, and the central tube is provided with a third pressure transmission hole at the corresponding position on the upper end of the second spring;

[0030] The lower end of the upper retaining ring is threadedly connected to a first rubber sleeve seat. The first rubber sleeve seat does not contact the central tube. At least two rubber sleeves are fitted on the outer side of the first rubber sleeve seat, and a separator ring is provided between each pair of rubber sleeves.

[0031] The cone is disposed on the lower outer wall of the first rubber sleeve seat and can slide relative to the first rubber sleeve seat. An outer cone is disposed at the lower end of the cone and the outer cone is in contact with the central tube. A water outlet hole is disposed above the outer cone.

[0032] The supporting sealing mechanism includes a limiting housing and a reversing mechanism;

[0033] The limiting housing is fitted onto the central tube and positioned below the cone. The lower end of the limiting housing is connected to the reversing mechanism.

[0034] The upper end of the limiting housing is provided with at least two locking grooves, and the middle part is provided with at least two straightening grooves;

[0035] Each slip groove contains a slip, the upper end of which has an inner cone, the outer wall of which has slip teeth, and the lower end of which is fixed in the slip groove.

[0036] Each straightening groove is provided with a straightening block. The outer walls of the upper and lower ends of the straightening groove protrude inward to prevent the straightening block from detaching from the limiting shell. A spring sheet is provided between the straightening block and the straightening groove to allow the straightening block to extend out of the limiting shell. The upper and lower ends of the straightening block are provided with inclined surfaces.

[0037] The reversing mechanism includes a reversing jacket and a lower connector;

[0038] The upper end of the reversing sleeve is threaded to the lower outer wall of the limiting housing, and the upper inner wall of the lower connector is threaded to the lower outer wall of the central tube.

[0039] The inner wall of the commutator sleeve is provided with a "7"-shaped groove, which is divided into a short groove and a long groove. The upper outer wall of the lower connector is provided with a commutator block. The commutator block is embedded in the short groove or the long groove. When the commutator block is embedded in the short groove, the lower connector and the commutator sleeve move synchronously. When the commutator block is embedded in the long groove, the lower connector and the commutator sleeve slide relative to each other.

[0040] The reverse thread is a left-hand thread, and the thread is a right-hand thread.

[0041] The hydraulic anchor teeth are made of drillable material and can be milled using wellbore treatment tools.

[0042] A method for using a long-lasting, easy-to-treat, washable well packer includes the following steps.

[0043] S1. Connecting the tubing string and lowering it into the well: Assemble a long-lasting, easy-to-handle washable packer and connect it to the designed position on the tubing string, then lower it into the well. When assembling the packer, install the reverse safety mechanism, anchoring release mechanism, backwash sealing mechanism, and support setting mechanism sequentially on the central tube. The lower connector reversing block is positioned in the short groove of the "7"-shaped groove on the inner wall of the reversing sleeve to ensure that the tool is safely lowered into the well and does not set midway.

[0044] S2, Setting: After the packer reaches the designed depth, the tubing is "lifted up - right-handed" and the lower connector reversing block is in the "7"-shaped groove on the inner wall of the reversing sleeve; the tubing is "lowered down", which moves the lower connector downwards, and the straightening block squeezes the slips upwards under the action of friction. The slips are extended and anchored under the action of the cone; the tubing is "lowered down" further, the slips are supported and limited, and the cone squeezes the rubber sleeve out and sets the packer;

[0045] S3, Water Injection: After the oil pipe is pressurized, the oil pipe pressure pushes the first piston through the second pressure transmission hole, causing the hydraulic anchor teeth to extend, anchoring the tubing string and preventing the packer from creeping. At the same time, the oil pipe pressure acts on the upper end face of the second piston through the third pressure transmission hole, causing the backwash channel to close.

[0046] S4. Well washing: After the tubing is depressurized, well washing fluid is injected into the annulus. The well washing fluid passes through the inlet hole, causing the second piston to move against the second spring force under the backwash pressure, opening the backwash channel. The well washing fluid flows out from the outlet hole and passes through the packer.

[0047] S5. Unsealing: After the tubing is depressurized, the hydraulic anchor retracts, and the second piston can move against the second spring force under the pressure of the lower part of the rubber sleeve, releasing the pressure of the lower casing, "lifting" the tubing string, driving the packer body to move upward, the rubber sleeve retracts, and the tubing string continues to be "lifted" until the slips retract.

[0048] S6. Release: If the packer fails to release, pressurize the tubing to shear the shear bolts, causing the locking sleeve to move downwards, the locking block to pop out, and the upper connector to disengage from the center tube by a clockwise rotation. The release mechanism, along with the hydraulic anchor teeth and water...

[0049] The anchor body is milled using wellbore processing tools.

[0050] The tool has high adaptability and reliability; before the locking block comes out, the upper connector and the central tube cannot rotate relative to each other around the axis, and torque can be transmitted to achieve packer setting. If the packer fails to unseal, the upper connector and the central tube can be disengaged by rotating clockwise after the locking block pops out by increasing the pressure through the oil pipe.

[0051] The hydraulic anchor body and anchor teeth are made of drillable materials. If the packer fails to release, the safety mechanism is used to release the string and pull out the tubing. Then, the hydraulic anchor body can be milled using wellbore treatment tools to reduce the risk of downhole accidents. Attached Figure Description

[0052] Figure 1 This is a schematic diagram of the structure of a long-lasting, easy-to-treat washable well packer according to the present invention;

[0053] Figure 2 This is a schematic diagram of the inverted safety mechanism of a washable well packer that is long-lasting and easy to handle according to the present invention;

[0054] Figure 3 This is a schematic diagram of the anchoring and unblocking mechanism of a washable well packer that is long-lasting and easy to handle according to the present invention;

[0055] Figure 4 This is a schematic diagram of the backwashing sealing mechanism of a long-lasting, easy-to-treat washable well packer according to the present invention;

[0056] Figure 5 This is a schematic diagram of the support seat sealing mechanism of a long-lasting, easy-to-treat washable well packer according to the present invention;

[0057] In the diagram: 1. Inverted safety mechanism; 101. Upper connector; 102. Locking sleeve; 103. Locking block; 104. Central tube; 105. Shear pin sleeve; 2. Anchoring and unlocking mechanism; 201. Hydraulic anchor tooth; 202. Hydraulic anchor body; 3. Backwashing and sealing mechanism; 301. Second spring; 302. Second piston; 303. Rubber sleeve; 304. Cone

[0058] 4. Supporting and sealing mechanism; 401. Slipper; 402. Straightening block; 403. Reversing outer sleeve; 404. Lower connector. Detailed Implementation

[0059] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example 1

[0060] Please see Figure 1 The present invention provides a long-lasting and easy-to-manage washable well packer, including a central tube 104, and an inverted safety mechanism 1, an anchoring and unblocking mechanism 2, a backwashing and sealing mechanism 3, and a support and setting mechanism 4 arranged sequentially from top to bottom on the central tube 104;

[0061] Please see Figure 1 , Figure 2The inverted safety mechanism 1 includes an upper connector 101, a locking sleeve 102, a locking block 103, and a shear pin sleeve 105. The inner wall of the upper end of the central tube 104 is connected to the outer wall of the lower end of the upper connector 101 by an inverted thread. The locking block 103 passes through the upper end of the central tube 104 and is inserted into the upper connector 101. The shear pin sleeve 105 is fitted on the outer wall of the central tube 104 below the upper connector 101. The shear pin sleeve 105 is connected to the central tube 104 by shear pins. The central tube 104 has a first pressure transmission hole at a corresponding position on the upper end of the shear pin sleeve 105. The locking sleeve 102 is threadedly connected to the outer wall of the shear pin sleeve 105. The locking sleeve 102 covers the locking block 103. The inner wall of the locking sleeve 102 above the locking block 103 has a receiving groove.

[0062] Please see Figure 1 , Figure 3 The anchoring and unlocking mechanism 2 includes a hydraulic anchor tooth 201 and a hydraulic anchor body 202. The hydraulic anchor body 202 is fitted onto the central tube 104. The two ends of the hydraulic anchor tooth 201 are fixed to the outer wall of the hydraulic anchor body 202. The hydraulic anchor body 202 has a through hole in the corresponding area of ​​the hydraulic anchor tooth 201. A first piston is installed in the through hole. A first spring is installed between the first piston and the hydraulic anchor tooth 201. At least two sets of hydraulic anchor teeth 201, through holes, first pistons, and first springs are provided. The hydraulic anchor body 202 has two through holes in the corresponding area of ​​the hydraulic anchor tooth 201. The middle of the hydraulic anchor tooth 201 is fixed between the two through holes. The central tube 104 has a pressure groove in the corresponding area of ​​the hydraulic anchor tooth 201. A second pressure transmission hole is installed in the pressure groove.

[0063] Please see Figure 1 , Figure 4 The backwash sealing mechanism 3 includes a water inlet sleeve, an upper retaining ring, and a cone 304. The water inlet sleeve is threaded to the lower outer wall of the hydraulic anchor 202. A second spring 301 is provided above the annular space between the water inlet sleeve and the central tube 104. A second piston 302 is provided at the lower end of the second spring 301. The lower end face of the second piston 302 is an outer cone surface. The upper retaining ring is threaded to the lower inner wall of the water inlet sleeve. The upper retaining ring does not contact the central tube 104. The upper end face of the upper retaining ring is an inner cone surface. The lower end face of the second piston 302 is in contact with the upper end face of the upper retaining ring. A second water inlet hole is provided above the upper end face of the upper retaining ring in the water inlet sleeve. A third pressure transmission hole is provided at the corresponding position on the upper end of the second spring 301 in the central tube 104.

[0064] The lower end of the upper retaining ring is threadedly connected to a first rubber sleeve seat. The first rubber sleeve seat does not contact the central tube 104. At least two rubber sleeves 303 are fitted on the outer side of the first rubber sleeve seat. A separator ring is provided between each pair of rubber sleeves 303. The cone 304 is provided on the lower end of the outer wall of the first rubber sleeve seat and can slide relative to the first rubber sleeve seat. An outer cone is provided at the lower end of the cone 304. The outer cone contacts the central tube 104. A water outlet is provided above the outer cone of the cone 304.

[0065] Please see Figure 1 , Figure 5 The supporting sealing mechanism 4 includes a limiting shell, a reversing outer sleeve 403, and a lower connector 404. The limiting shell is fitted onto the central tube 104 and positioned below the cone 304. The upper end of the limiting shell is provided with at least two slip grooves, and the middle part is provided with at least two straightening grooves. Each slip groove is provided with a slip 401. The upper end of the slip 401 is provided with an inner cone, and the outer wall of the inner cone is provided with slip teeth. The lower end of the slip 401 is fixed in the slip groove. Each straightening groove is provided with a straightening block 402. The outer walls of the upper and lower ends of the straightening groove protrude inward to prevent the straightening block 402 from detaching from the limiting shell. A spring sheet is provided between the straightening block and the straightening groove to allow the straightening block to extend out of the limiting shell. The upper and lower ends of the straightening block are provided with inclined surfaces.

[0066] The upper end of the reversing sleeve 403 is threadedly connected to the lower outer wall of the limiting housing, and the upper inner wall of the lower connector 404 is threadedly connected to the lower outer wall of the central tube 104. The inner wall of the reversing sleeve 403 is provided with a "7"-shaped groove, which is divided into a short groove and a long groove. The upper outer wall of the lower connector 404 is provided with a reversing block, which is embedded in the short groove or the long groove. When the reversing block is embedded in the short groove, the lower connector 404 and the reversing sleeve 403 move synchronously. When the reversing block is embedded in the long groove, the lower connector 404 and the reversing sleeve 403 slide relative to each other.

[0067] The reverse thread is a left-hand thread, and the thread is a right-hand thread.

[0068] The hydraulic anchor tooth 201 is made of a drillable material and can be milled using wellbore treatment tools. Example 2

[0069] Based on Example 1, the present invention provides a method for using a long-lasting, easily treatable, washable well packer, comprising the following steps.

[0070] S1. Connecting the tubing string and lowering it into the well: Assemble a long-lasting, easy-to-handle washable packer and connect it to the designed position on the tubing string, then lower it into the well. During assembly, the reverse safety mechanism 1, the anchoring and unblocking mechanism 2, the backwashing and sealing mechanism 3, and the support and setting mechanism 4 are sequentially set on the central tube 104. The reversing block of the lower connector 404 is located in the short groove of the "7"-shaped groove on the inner wall of the reversing sleeve 403 to ensure that the tool is safely lowered into the well and does not set midway.

[0071] S2, Setting: After the packer reaches the designed depth, the tubing is "lifted up and rotated right". The reversing block of the lower connector 404 is in the "7"-shaped groove on the inner wall of the reversing sleeve 403. The tubing is "lowered down", which drives the lower connector 404 to move downward. The straightening block 402 presses the slip 401 upward under the action of friction. The slip 401 is extended and anchored under the action of the cone 304. The tubing continues to be "lowered down". The slip 401 is supported and limited. The cone 304 presses the rubber sleeve 303 to push it out and set.

[0072] S3, Water Injection: After the oil pipe is pressurized, the oil pipe pressure pushes the first piston through the second pressure transmission hole, causing the hydraulic anchor 201 to extend, anchoring the tubing string and preventing the packer from creeping. At the same time, the oil pipe pressure acts on the upper end face of the second piston 302 through the third pressure transmission hole, causing the backwash channel to close.

[0073] S4. Well washing: After the tubing is depressurized, well washing fluid is injected into the annulus. The well washing fluid passes through the inlet hole, causing the second piston 302 to move against the spring force of the spring 301 under the backwash pressure, opening the backwash channel. The well washing fluid flows out from the outlet hole and passes through a long-lasting and easy-to-treat well washing packer.

[0074] S5. Unsealing: After the tubing is depressurized, the hydraulic anchor 201 retracts, and the second piston 302 can move under the pressure of the lower part of the rubber sleeve 303 to overcome the spring force of the spring 301, releasing the pressure of the lower casing, "lifting" the tubing string, driving the packer body to move upward, the rubber sleeve 303 retracts, and the tubing string continues to be "lifted" and the slip 401 retracts.

[0075] S6. Release: If a long-lasting, easy-to-treat washable packer fails to release, pressure is applied to the tubing to cut the shear pins with the shear pin sleeve 105, causing the locking sleeve 102 to move down and the locking block 103 to pop out. The upper connector 101 can be disengaged from the central tube 104 by turning right. The release part, hydraulic anchor teeth 201, and hydraulic anchor body 203 can be milled with wellbore treatment tools.

[0076] All components not discussed in detail in this application, as well as the connection methods of these components, are well-known technologies in this field. They can be directly applied and will not be elaborated further.

[0077] In this invention, the term "multiple" refers to two or more unless otherwise explicitly defined. The terms "install," "connect," "link," and "fix" should be interpreted broadly. For example, "connect" can be a fixed connection, a detachable connection, or an integral connection; "link" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0078] In the description of this invention, it should be understood that the terms "upper," "lower," "left," "right," "front," "rear," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or unit referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0079] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0080] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A long-lasting, easy-to-manage washable well packer, comprising a central tube and, from top to bottom, an anchoring and unblocking mechanism, a backwashing and sealing mechanism, and a supporting and setting mechanism, sequentially arranged on the central tube, characterized in that, It also includes an inverted safety mechanism, which is mounted on the central tube and located above the anchoring and unlocking mechanism; The anchoring and release mechanism includes a hydraulic anchor body; The backwash sealing mechanism includes an inlet sleeve, an upper retaining ring, and a cone. The lower end of the hydraulic anchor body is threadedly connected to a water inlet sleeve. A second spring is installed above the annular space between the water inlet sleeve and the central tube. A second piston is installed at the lower end of the second spring. The lower end face of the second piston is an outer conical surface. The upper retaining ring is threaded to the inner wall of the lower end of the water inlet sleeve. The upper retaining ring does not contact the central tube. The upper end face of the upper retaining ring is an inner conical surface. The lower end face of the second piston is in contact with the upper end face of the upper retaining ring. The water inlet sleeve has a water inlet hole above the upper end face of the upper baffle ring, and the central tube has a third pressure transmission hole at the corresponding position on the upper end of the second spring. The lower end of the upper retaining ring is threadedly connected to a first rubber sleeve seat. The first rubber sleeve seat does not contact the central tube. At least two rubber sleeves are fitted on the outer side of the first rubber sleeve seat, and a separator ring is provided between each pair of rubber sleeves. The cone is disposed on the lower outer wall of the first rubber sleeve seat and can slide relative to the first rubber sleeve seat. An outer cone is disposed at the lower end of the cone and contacts the central tube. A water outlet hole is disposed above the outer cone. The supporting sealing mechanism includes a limiting housing and a reversing mechanism; The reversing mechanism includes a reversing jacket and a lower connector; The upper end of the reversing sleeve is threaded to the lower outer wall of the limiting housing, and the upper inner wall of the lower connector is threaded to the lower outer wall of the central tube. The inner wall of the commutator sleeve is provided with a "7"-shaped groove, which is divided into a short groove and a long groove. The upper outer wall of the lower connector is provided with a commutator block, which is embedded in the short groove or the long groove. When the commutator block is embedded in the short groove, the lower connector and the commutator sleeve move synchronously. When the commutator block is embedded in the long groove, the lower connector and the commutator sleeve slide relative to each other.

2. The long-lasting, easy-to-treat, washable well packer according to claim 1, characterized in that, The inverted safety mechanism includes an upper connector, a locking sleeve, a locking block, and a shear pin sleeve; The inner wall of the upper end of the central tube is connected to the outer wall of the lower end of the upper connector by a reverse thread, and the locking block passes through the upper end of the central tube and is inserted into the upper connector. The central tube has a shear pin sleeve fitted on the outer wall below the upper connector. The shear pin sleeve is connected to the central tube through shear pins. The central tube has a first pressure transmission hole at the corresponding position on the upper end of the shear pin sleeve. The outer wall of the clipper sleeve is threaded with a locking sleeve, which covers the locking block. The inner wall of the locking sleeve above the locking block has a receiving groove.

3. A long-lasting, easy-to-treat, washable well packer according to claim 2, characterized in that, The anchoring and unlocking mechanism also includes hydraulic anchor teeth; The hydraulic anchor body is fitted onto the central tube, and the two ends of the hydraulic anchor teeth are fixed to the outer wall of the hydraulic anchor body. The hydraulic anchor body has through holes in the corresponding areas of the hydraulic anchor teeth. A first piston is provided inside the through hole, and a first spring is provided between the first piston and the hydraulic anchor tooth; at least two sets of hydraulic anchor tooth, through hole, first piston, and first spring are provided; The central pipe is provided with a pressure groove in the area corresponding to the hydraulic anchor tooth, and a second pressure transmission hole is provided in the pressure groove; The hydraulic anchor teeth are made of drillable material and can be milled using wellbore treatment tools.

4. A long-lasting, easy-to-treat, washable well packer according to claim 3, characterized in that, The hydraulic anchor body has two through holes in the area corresponding to the hydraulic anchor tooth, and the hydraulic anchor tooth is fixed between the two through holes.

5. A long-lasting, easy-to-treat, washable well packer according to claim 4, characterized in that, The limiting housing is fitted onto the central tube and positioned below the cone. The lower end of the limiting housing is connected to the reversing mechanism. The upper end of the limiting housing is provided with at least two locking grooves, and the middle part is provided with at least two straightening grooves; Each slip groove contains a slip, the upper end of which has an inner cone, the outer wall of which has slip teeth, and the lower end of which is fixed in the slip groove. Each straightening groove is provided with a straightening block. The outer walls of the upper and lower ends of the straightening groove protrude inward to prevent the straightening block from detaching from the limiting shell. A spring sheet is provided between the straightening block and the straightening groove to allow the straightening block to extend out of the limiting shell. The upper and lower ends of the straightening block are provided with inclined surfaces.

6. A long-lasting, easily treated, washable well packer according to claim 5, characterized in that, The reverse thread is a left-hand thread.

7. A method of using the long-lasting, easily treatable, washable well packer as described in claim 6, characterized in that, Includes the following steps, S1. Connect the tubing string and run it into the well: Assemble a long-lasting, easy-to-clean, washable packer and connect it to the designed position on the tubing string, then run it into the well. S2, Setting: After the packer is lowered to the design depth, "lift up - right-hand rotation" of the tubing, "lower down" the tubing to make the slips extend and anchor, and continue "lowering down" the tubing to make the rubber sleeve extend and set; S3, Water Injection: After the oil pipe is pressurized, the hydraulic anchor teeth are extended and the pipe string is anchored, and the backwash channel is closed; S4. Well washing: After depressurization of the tubing, well washing fluid is injected into the annulus of the tubing and casing. The well washing fluid flows out from the outlet through the inlet hole and backwashing channel, and passes through the packer. S5. Unsealing: After the tubing is depressurized, the hydraulic anchor retracts, and the second piston moves against the second spring force under the pressure of the lower part of the rubber sleeve, releasing the pressure of the lower casing, "lifting" the tubing string, driving the packer body to move upward, the rubber sleeve retracts, and the tubing string continues to be "lifted" until the slips retract. S6. Release: If the packer fails to release, pressurize the tubing to cut the shear pins, causing the locking sleeve to move down, the locking block to pop out, and the upper connector to disengage from the central tube by turning clockwise. The release part, hydraulic anchor teeth, and hydraulic anchor body are milled using wellbore treatment tools.

8. The method of use according to claim 7, characterized in that, During assembly, the inverted safety mechanism, anchoring and unblocking mechanism, backwashing and sealing mechanism, and support and setting mechanism are sequentially installed on the central tube; and the reversing block of the lower connector is located in the short groove of the "7"-shaped groove on the inner wall of the reversing sleeve to ensure that the tool is safely inserted into the well and does not set midway.

9. The method of use according to claim 7, characterized in that, The "lift-right rotation" of the tubing causes the reversing block of the lower connector to be positioned in the "7"-shaped groove on the inner wall of the reversing sleeve. The "lowering" of the tubing causes the lower connector to move downwards, and the straightening block, under the action of friction, presses the slip upwards. The slip is then extended and anchored under the action of the cone. The tubing continues to be lowered, the slip is supported and limited, and the cone presses the rubber sleeve out and sets it.

10. The method of use according to claim 7, characterized in that, During water injection, the oil pipe pressure pushes the first piston through the second pressure transmission hole, causing the hydraulic anchor teeth to extend, anchoring the tubing string and preventing packer creep. At the same time, the oil pipe pressure acts on the upper end face of the second piston through the third pressure transmission hole, closing the backwash channel. During well washing, the washing fluid enters through the inlet hole, causing the second piston to move under the backwash pressure, overcoming the elastic force of the second spring, opening the backwash channel. The washing fluid then flows out from the outlet hole and passes through the packer.

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