Packer-screen pipe combined device

Abstract

The invention belongs to the technical field of oil exploration and development, and discloses a packer-screen pipe combined device, a screen pipe in the combined device comprises a mandrel, a reset mechanism and an outer cylinder, the outer cylinder is provided with a first flow guide channel, the mandrel is provided with a second flow guide channel, and the mandrel can move downwards in the axial direction under the action of pressure. The reset mechanism can enable the mandrel to move upwards after pressure relief and provide two different stroke end points for any two adjacent times of upward movement of the mandrel, the two stroke end points are the first end point and the second end point respectively, when the mandrel moves to the first end point, the second flow guide channel is communicated with the first flow guide channel, and when the mandrel moves to the second end point, the second flow guide channel is communicated with the second flow guide channel. The second flow guide channel and the first flow guide channel are staggered, and multiple times of opening and closing of the screen pipe can be achieved by applying pressure to the mandrel.

Description

Technical Field

[0001] The invention relates to the technical field of petroleum exploration and development, and in particular to a packer-screen pipe combination device. Background Art

[0002] The traditional downhole testing process uses multi-flow test valves from Johnston or LPR-N valves and selective test valves from Halliburton to achieve negative pressure perforation and multiple well opening and closing. However, it has the following shortcomings in low permeability reservoir testing: the traditional test valve can only be set above the packer, which is far from the reservoir, resulting in a long test pocket; if a low permeability reservoir is encountered, the fluid output is small and the pressure recovery speed is slow. The above traditional process is sometimes difficult to overcome the influence of the wellbore storage effect of low permeability and low permeability reservoirs, resulting in partial When the wells were divided and shut down, no radial flow occurred, and it was impossible to interpret the formation parameters and obtain qualified formation fluid samples, which affected the oil test conclusion and the accurate characterization of the formation fluid. Traditional downhole test valves such as multi-flow test valves, LPR-N valves, and selective test valves have the disadvantages of complex structure, difficult operation, and high labor intensity. They require a high number of construction personnel and their proficiency, resulting in high costs and high failure rates for traditional testing operations. When using the test string and process of traditional test valves, after the oil test is completed, it is necessary to kill the well, pull out the test string, and then lower another completion string for production.

[0003] Chinese invention patent CN201510237285.5 discloses a packer-screen tube combination device that can be opened and closed multiple times. The test well string composed of the packer-screen tube combination device can control the opening and closing of the production channel of the fluid in and out of the test well string without a test valve. The structure is simple and the cost is low. However, the disadvantage of the device is that the device uses several screen tube sub-units, has no reset mechanism, and the total number of openings and closings is limited. The number of openings and closings does not exceed two times, which makes it difficult to meet the needs of multiple openings and closings in oil testing and completion operations. Summary of the invention

[0004] The object of the present invention is to provide a packer-screen combination device, which has no limit on the number of times of opening and closing a well, so as to meet the requirements of multiple opening and closing of a well in oil testing and well completion operations.

[0005] To achieve this object, the present invention adopts the following technical solutions:

[0006] The packer-screen tube assembly device comprises a pressure transmission joint, a packer and a screen tube connected in sequence, and also comprises a pressure transmission tube, the two ends of which are respectively inserted into the pressure transmission joint and the screen tube;

[0007] The pressure transmission joint is provided with a first production channel and a first pressurizing channel which are not connected to each other, and the pressure transmission pipe is connected to the first pressurizing channel;

[0008] The screen tube comprises a mandrel, an outer tube and a reset mechanism, the outer tube is provided with a second production channel and a second pressurization channel which are not connected to each other, the second production channel is connected to the first production channel, the second pressurization channel is connected to the pressure transmission pipe, the outer tube is also provided with a first flow guide channel which is connected to its inner wall and its outer wall, the mandrel is located in the outer tube and is connected to the second production channel, the mandrel is also provided with a second flow guide channel which is connected to its inner wall and its outer wall, a pressurization chamber and an air chamber which are axially spaced are formed between the mandrel and the outer tube, the pressurization chamber can be connected to the second pressurization channel and push the mandrel downward in the axial direction when pressurized, and air is trapped in the air chamber;

[0009] The reset mechanism can make the spindle move upward and provide two different travel end points for the two adjacent upward movements of the spindle, the two travel end points are the first end point and the second end point respectively. When the spindle moves to the first end point, the second guide channel is connected to the first guide channel. When the spindle moves to the second end point, the second guide channel is staggered with the first guide channel.

[0010] Preferably, the reset mechanism comprises a displacement sleeve, a pin and a reset spring, the displacement sleeve is arranged on the mandrel and is axially limited with the mandrel, a displacement groove is arranged on the displacement sleeve, one end of the pin is fixedly connected with the outer cylinder, and the other end is inserted into the displacement groove, one end of the reset spring abuts against the mandrel, and the other end abuts against the outer cylinder;

[0011] The transposition groove is formed by connecting a first Y-shaped groove and a second Y-shaped groove which are circumferentially staggered. The first Y-shaped groove and the second Y-shaped groove both include a first branch, a second branch and a third branch. The first branch extends along the axial direction of the transposition sleeve. The second branch and the third branch are both arranged in an L shape and are both connected to the first branch. The end of the second branch connected to the first branch extends along the axial direction of the transposition sleeve. The other end of the second branch is inclined in a direction away from the third branch. The end of the third branch connected to the first branch is inclined in a direction away from the first branch. The other end of the third branch extends along the axial direction of the transposition sleeve. The second branch and the third branch of adjacent first Y-shaped grooves and second Y-shaped grooves are connected. The length of the first branch of the first Y-shaped groove is less than the length of the first branch of the second Y-shaped groove. The end of the first branch of the second Y-shaped groove away from the second branch and the third branch is the second end point. The end of the first branch of the first Y-shaped groove away from the second branch and the third branch is the first end point.

[0012] Preferably, the outer tube includes an upper joint, a lower joint and a cylinder body, the front end of the upper joint is connected to the packer, the rear end of the upper joint is inserted into the cylinder body and connected to the cylinder body, and the front end of the lower joint is inserted into the cylinder body and connected to the cylinder body.

[0013] Preferably, the upper joint includes a fixed joint, a protection joint, a shear joint and a rupture disc joint, the fixed joint is connected to the packer, the shear joint and the protection joint are respectively sealed with the inner side and the outer side of the fixed joint, the front end of the mandrel is inserted in the shear joint, the shear joint and the protection joint are enclosed to form an annular space, the front end of the rupture disc joint is clamped between the shear joint and the protection joint and is sealed with the shear joint and the protection joint, the rear end of the rupture disc joint is clamped between the mandrel and the outer cylinder and is sealed with the mandrel and the outer cylinder, the rupture disc joint, the shear joint and the mandrel are jointly enclosed to form the pressurized chamber, the air chamber is formed by the rupture disc joint and the mandrel, the rupture disc is arranged in the mounting hole opened in the rupture disc joint, the two sides of the mounting hole correspond to the pressurized chamber and the annular space respectively, a connecting channel is opened in the fixed joint, one end of the connecting channel is communicated with the pressure transmission pipe, and the other end is communicated with the annular space, the annular space, the connecting channel and the mounting hole together constitute the second pressurized channel.

[0014] Preferably, the spindle is provided with a first stop ring and a second stop ring at intervals along the axial direction, and the shift sleeve is sleeved on the spindle and located between the first stop ring and the second stop ring.

[0015] Preferably, the core shaft is arranged in sections, including a power shaft section and a reset shaft section connected along the axial direction, the pressurized chamber and the air chamber are formed by the power shaft section and the outer cylinder, and the second guide channel, the first retaining ring and the second retaining ring are arranged on the reset shaft section.

[0016] Preferably, the connecting channel includes a radial channel and an axial channel, one end of the radial channel passes through the wall of the fixed joint and is sealed with a wire plug, the other end of the radial channel is connected to the pressure transmission pipe, one end of the axial channel is connected to the radial channel, and the other end is connected to the annular space.

[0017] Preferably, a rupture disk is provided in the second pressurizing channel.

[0018] Preferably, a shear pin is further provided between the mandrel and the outer cylinder.

[0019] Beneficial effects of the present invention: a reset mechanism and a power chamber are provided in the packer-screen combination device of the present invention. The mandrel is moved downward by applying pressure to the power chamber. After the pressure is released, the reset mechanism can move the mandrel upward, and two different travel endpoints are provided for any two adjacent upward movements of the mandrel, namely the first endpoint and the second endpoint. When the mandrel moves upward to the first endpoint, the second diversion channel is connected to the first diversion channel. When the mandrel moves upward to the second endpoint, the second diversion channel is staggered with the first diversion channel, respectively corresponding to the open and closed states of the screen, realizing unlimited number of well opening and closing near the reservoir, improving the quality of oil test data acquisition, and each opening and closing operation pressure does not need to increase the pressure level compared with the previous operation, and has low requirements on the casing pressure bearing capacity. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a schematic diagram of a packer-screen assembly according to an embodiment of the present invention;

[0021] Figure 2 yes Figure 1 A schematic diagram of the enlarged structure at A in the middle;

[0022] Figure 3 yes Figure 1 A schematic diagram of the enlarged structure at B in the middle;

[0023] Figure 4 yes Figure 1 Schematic diagram of the enlarged structure at C in the middle;

[0024] Figure 5 yes Figure 1 Schematic diagram of the enlarged structure at D in the middle;

[0025] Figure 6 yes Figure 1 Schematic diagram of the enlarged structure at E in the middle;

[0026] Figure 7 is a schematic structural diagram of a pressure transmission joint in an embodiment of the present invention;

[0027] Figure 8 is a schematic structural diagram of an upper joint in an embodiment of the present invention;

[0028] Fig. 9 It is a schematic structural diagram of a transposition sleeve in an embodiment of the present invention.

[0029] In the figure: 1, pressure transmission joint; 11, screw plug; 2, packer; 3, screen tube; 31, outer tube; 311, upper joint; 3111, fixed joint; 3112, shear joint; 3113, protection joint; 3114, rupture disk joint; 3115, rupture disk; 312, cylinder; 3121, transposition cylinder section; 3122, spring cylinder section; 313, lower joint; 32, spindle; 321, power shaft section; 322, reset shaft section; 3221, first gear snap ring; 3222, second gear snap ring; 33, reset spring; 34, transposition sleeve; 341, transposition groove; 3411, first branch; 3412, second branch; 3413, third branch; 35, pin shaft; 36, shear pin; 4, pressure transmission tube;

[0030] a, first pressurized channel; b, first production channel; c, second production channel; d, first flow guide channel; e, second flow guide channel; f, annular space; g, pressurized chamber; h, air chamber; i, connecting channel; j, mounting hole. DETAILED DESCRIPTION

[0031] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0032] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0034] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0035] Figure 1-Figure 9 The figure shows a packer-screen combination device proposed in an embodiment of the present invention, which includes a pressure transmission joint 1, a packer 2, a pressure transmission pipe 4 and a screen 3, wherein the pressure transmission joint 1, the packer 2 and the screen 3 are sequentially connected in series from the front end to the rear end (the front end refers to the end close to the wellhead, and the rear end refers to the end away from the wellhead), the two ends of the pressure transmission pipe 4 are respectively penetrated in the pressure transmission joint 1 and the screen 3 and are sealedly connected with the pressure transmission joint 1 and the screen 3, the pressure transmission joint 1 is provided with a first production channel b and a first pressurizing channel a which are not connected to each other, the pressure transmission pipe 4 is connected to the first pressurizing channel a, the screen 3 includes a core shaft 32, an outer tube 31 and a reset mechanism, and the outer tube 31 is provided with a plurality of pressure channels which are not connected to each other. The second production channel c and the second pressurization channel are connected, the second production channel c is connected to the first production channel b, the second pressurization channel is connected to the pressure transmission pipe 4, the outer cylinder 31 is also provided with a first guide channel d connecting its own inner wall and its own outer wall, the core shaft 32 is located in the outer cylinder 31 and is connected to the second production channel c, and the core shaft 32 is also provided with a second guide channel e connecting its own inner wall and its own outer wall. An axially spaced pressurization chamber g and a closed air chamber h are formed between the core shaft 32 and the outer cylinder 31. The pressurization chamber g can be connected to the second pressurization channel and then to the outside of the pressure transmission joint 1 through the pressure transmission pipe 4 and the first pressurization channel a, and air is enclosed in the air chamber h.

[0036] After the pressurized fluid is injected into the pressurized chamber g, the spindle 32 can move downward in the axial direction. After the pressure is released, the reset mechanism can make the spindle 32 move upward, and provide two different travel end points for the two adjacent upward movements of the spindle 32, namely the first end point and the second end point. When the spindle 32 moves to the first end point, the second guide channel e on the spindle 32 is connected with the first guide channel d on the outer cylinder 31. When the spindle 32 moves to the second end point, the second guide channel e on the spindle 32 is staggered with the first guide channel d on the outer cylinder 31.

[0037] The mandrel 32 of the above-mentioned packer-screen combination device applies pressure to the pressure chamber g through the first pressure channel a, the pressure transmission tube 4, and the second pressure channel, so that the mandrel 32 moves downward. When the pressure is cancelled, the reset mechanism can drive the mandrel 32 upward, and two travel end points are set for the mandrel 32. When the mandrel 32 moves to the first end point, the second guide channel e on the mandrel 32 is connected with the first guide channel d on the outer tube 31, and the screen tube 3 is opened; when the mandrel 32 moves to the second end point, the second guide channel e on the mandrel 32 is staggered with the first guide channel d on the outer tube 31, and the screen tube 3 is closed. Since the two adjacent travel end points of the mandrel 32 are different, the screen tube 3 can realize the conversion of the open and closed states after the mandrel 32 is subjected to force each time. That is to say, by applying a downward external force to the core shaft 32, the screen 3 can be switched from open to closed or from closed to open. The screen 3 can be opened or closed an unlimited number of times, allowing the fluid in the formation to flow out of the ground through the core shaft 32, thereby meeting the needs of multiple well openings and closings during oil testing and production operations. Moreover, the high pressure of the casing annulus required for multiple openings and closings does not need to be increased step by step, and the pressure-bearing capacity of the casing above the isolation device is low.

[0038] refer to Figure 5 As shown, the reset mechanism includes a displacement sleeve 34, a pin shaft 35 and a reset spring 33. The displacement sleeve 34 is sleeved on the main shaft 32 and is axially limited with the main shaft 32. A displacement groove 341 is provided on the displacement sleeve 34. One end of the pin shaft 35 is fixedly connected to the outer cylinder 31, and the other end is inserted into the displacement groove 341 and can move along the extension direction of the displacement groove 341. One end of the reset spring 33 is connected to the main shaft 32, and the other end is connected to the outer cylinder 31 to provide a reset force for the main shaft 32.

[0039] refer to Fig. 9As shown, the transposition groove 341 is formed by connecting a first Y-shaped groove and a second Y-shaped groove which are staggered in the circumferential direction, and the first Y-shaped groove and the second Y-shaped groove both include a first branch 3411, a second branch 3412 and a third branch 3413, the first branch 3411 extends along the axial direction of the transposition sleeve 34, the second branch 3412 and the third branch 3413 are both arranged in an L shape and are both connected to the first branch 3411, wherein one end of the second branch 3412 connected to the first branch 3411 extends along the axial direction of the transposition sleeve 34, and the other end is inclined in a direction away from the third branch 3413, and one end of the third branch 3413 connected to the first branch 3411 is inclined in a direction away from the first branch 3411 , and the other end extends along the axial direction of the transposition sleeve 34, and the adjacent second branches 3412 and third branches 3413 of the first Y-shaped groove and the second Y-shaped groove are connected. The difference is that the length of the first branch 3411 of the first Y-shaped groove is less than the length of the first branch 3411 of the second Y-shaped groove. When the pin 35 moves to the end of the first branch 3411 of the first Y-shaped groove away from the second branch 3412 and the third branch 3413, the spindle 32 is at the first end point. When the pin 35 moves to the end of the first branch 3411 of the second Y-shaped groove away from the second branch 3412 and the third branch 3413, the spindle 32 is at the second end point. At this time, the second guide channel e is located above the first guide channel d.

[0040] When the transposition sleeve 34 overcomes the elastic force of the return spring 33 under the action of external force and moves downward with the spindle 32, the pin shaft 35 moves upward relatively, and enters the third branch 3413 of the adjacent first Y-shaped groove from the first branch 3411 of the second Y-shaped groove through the guiding action of the second branch 3412. After the pressure is relieved, under the elastic force of the return spring 33 and the guiding action of the third branch 3413, the pin shaft 35 enters the first branch 3411 of the first Y-shaped groove and moves to the end of the first branch 3411 away from the second branch 3412 and the third branch 3413. The spindle 32 moves to the first end point, the first guide channel d is connected to the second guide channel e, and the screen tube 3 is opened. When the screen tube 3 needs to be closed, it only needs to be closed again. When the external force is applied to the mandrel 32 again, the displacement sleeve 34 overcomes the elastic force of the reset spring 33 under the external force and moves downward with the mandrel 32, the pin 35 moves upward relatively, and enters the third branch 3413 of the adjacent second Y-shaped groove from the first branch 3411 of the first Y-shaped groove through the guiding action of the second branch 3412. After the pressure is relieved, under the elastic force of the reset spring 33 and the guiding action of the third branch 3413, the pin 35 enters the first branch 3411 of the second Y-shaped groove and moves to the end of the first branch 3411 away from the second branch 3412 and the third branch 3413, the mandrel 32 moves to the second end point, the first guide channel d and the second guide channel e are closed, and the screen tube 3 is closed. In actual application, it is only necessary to repeat the above operation to realize the opening and closing of the screen tube 3 for an unlimited number of times.

[0041] In other embodiments, the reset mechanism may also be designed with reference to the structural principle of a push-on cylindrical pen. Push-on ballpoint pens belong to the prior art and will not be further described here.

[0042] refer to Figure 1 and Figure 7 As shown, the first production channel b axially penetrates the pressure transmission joint 1, one end of the first pressurized channel a is connected to the pressure transmission pipe 4 inserted into the pressure transmission joint 1, and the other end is connected to the outer wall of the pressure transmission joint 1, so as to transmit the pressure of the oil casing annulus formed between the packer-screen pipe assembly and the wellbore after the packer-screen pipe assembly is lowered into the well to the pressure transmission pipe 4. Exemplarily, a threaded blind hole is provided in the pressure transmission joint 1, the first pressurized channel a is connected to the threaded blind hole, and the pressure transmission pipe 4 is inserted into the threaded blind hole and is sealed and threadedly connected to the pressure transmission joint 1.

[0043] refer to Figure 1 and Figure 6 As shown, the outer tube 31 includes an upper joint 311, a lower joint 313 and a barrel 312. The front end of the upper joint 311 is connected to the packer 2, and the rear end is inserted into the barrel 312 and connected to the barrel 312. The front end of the lower joint 313 is inserted into the barrel 312 and connected to the barrel 312, and the rear end is used to connect other functional pipe strings. One end of the reset spring 33 abuts against the front end face of the lower joint 313, and the other end abuts against the first retaining ring 3222. The first guide channel d is also opened on the lower joint 313.

[0044] Furthermore, the upper joint 311 includes a fixed joint 3111, a protection joint 3113, a shear joint 3112 and a rupture disk joint 3114, wherein the front end of the fixed joint 3111 is sealed and threaded with the packer 2, and a step blind cavity is provided at one end of the fixed joint 3111 close to the packer 2, and the blind cavity is divided into a large diameter section and a small diameter section. The second production channel c is provided in the fixed joint 3111, one end of which is connected with the large diameter section, and the other end is connected with the end face of the fixed joint 3111 away from the packer 2, the second pressurized channel is connected with the small diameter section, the pressure transmission pipe 4 is inserted into the small diameter section through the large diameter section and is sealed and connected with the fixed joint 3111, thereby preventing the second production channel c from being connected with the second pressurized channel, and the shear joint 3112 and the protection joint 3113 are divided into a plurality of pressure transmission pipes 3112 and a plurality of pressure transmission pipes 3113. The shear joint 3112 and the protective joint 3113 are respectively sealed and threaded with the inner and outer sides of the fixed joint 3111, the shear joint 3112 and the protective joint 3113 enclose an annular space f, the front end of the rupture disk joint 3114 is clamped between the shear joint 3112 and the protective joint 3113 and is sealedly connected to the shear joint 3112 and the protective joint 3113 to block the rear end of the annular space f, the rear end of the rupture disk joint 3114 is clamped between the core shaft 32 and the outer cylinder 31 and is sealedly connected to the core shaft 32 and the outer cylinder 31, the front end of the core shaft 32 is inserted into the shear joint 3112, the inner wall surface of the rupture disk joint 3114, the end surface of the shear joint 3112 and the outer wall surface of the core shaft 32 together enclose the above-mentioned pressurized chamber g, and the air chamber h is formed by the rupture disk joint 3114 and the core shaft 32. The rupture disk 3115 is arranged in the mounting hole provided in the rupture disk joint 3114, and the two sides of the mounting hole correspond to the pressurized chamber g and the annular space f respectively. A connecting channel i is provided in the fixed joint 3111, and one end of the connecting channel i is connected to the pressure transmission pipe 4, and the other end is connected to the annular space f. The annular space f, the connecting channel i and the mounting hole together constitute a second pressurized channel. Since the second pressurized channel is connected to the pressure transmission pipe 4, and the pressure transmission pipe 4 is connected to the first pressurized channel a, after the rupture disk 3115 ruptures, the second pressurized channel can be connected to the first pressurized channel a. Based on the above arrangement, when installing the rupture disk 3115, it is only necessary to radially open a through mounting hole on the rupture disk joint 3114, and then install the rupture disk 3115 in the mounting hole.

[0045] refer to Figure 5As shown, in order to achieve axial limitation of the mandrel 32 and the transposition sleeve 34, the mandrel 32 is provided with a first stop snap ring 3221 and a second stop snap ring 3222 at intervals along the axial direction, wherein the second stop snap ring 3222 is located at an end of the first stop snap ring 3221 away from the upper joint 311, and the transposition sleeve 34 is sleeved on the mandrel 32 and located between the first stop snap ring 3221 and the second stop snap ring 3222. For easy installation, one of the first stop snap ring 3221 and the second stop snap ring 3222 is detachably connected to the mandrel 32, and the other can be integrally formed with the mandrel 32. Exemplarily, for the convenience of assembly, the spindle 32 is arranged in sections, including a power shaft section 321 and a reset shaft section 322 connected along the axial direction, the pressurized chamber g and the air chamber h are both enclosed by the power shaft section 321 and the outer tube 31, the second guide channel e, the first retaining ring 3221 and the second retaining ring 3222 are arranged on the reset shaft section 322, and the split spindle 32 can reduce the difficulty of inserting the spindle 32 into the outer tube 31.

[0046] refer to Figure 2 and Figure 8 As shown, in order to reduce the processing difficulty of the connecting channel i, the connecting channel i includes a radial channel and an axial channel, one end of the radial channel penetrates the wall of the fixed joint 3111 and is blocked with a wire plug 11, and the other end is connected to the pressure transmission pipe 4. One end of the axial channel is connected to the radial channel, and the other end is connected to the annular space f. During processing, the radial channel and the axial channel can be processed along the radial direction and axial direction of the fixed joint 3111 respectively, and then the wire plug 11 is inserted into one end of the radial channel that penetrates the wall of the fixed joint 3111.

[0047] A shear pin 36 is also radially arranged between the core shaft 32 and the outer cylinder 31. When the pressure difference between the core shaft 32 and the outer cylinder 31 is greater than the shear force that the shear pin 36 can withstand, the shear pin 36 is sheared off, and axial movement can occur between the core shaft 32 and the outer cylinder 31, thereby avoiding axial displacement between the core shaft 32 and the outer cylinder 31 caused by excessive pressure in the core shaft 32 during the downhole process.

[0048] refer to Figure 5 As shown, in this embodiment, the cylinder 312 is divided into two parts, including a transposition cylinder section 3121 and a spring cylinder section 3122 connected in the axial direction, wherein the pin 35 is fixed to the transposition cylinder section 3121, and the return spring 33 is arranged between the spring cylinder section 3122 and the mandrel 32, and the rear end of the transposition cylinder section 3121 is inserted into the spring cylinder section 3122 and screwed to the spring cylinder section 3122. The divided cylinder 312 can further reduce the difficulty of assembling the entire combined device.

[0049] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A packer-screen tube assembly, comprising a pressure transmission joint (1), a packer (2) and a screen tube (3) connected in sequence, and a pressure transmission tube (4), wherein two ends of the pressure transmission tube (4) are respectively inserted into the pressure transmission joint (1) and the screen tube (3), and characterized in that: The pressure transmission joint (1) is provided with a first production channel (b) and a first pressurizing channel (a) which are not connected to each other, and the pressure transmission pipe (4) is connected to the first pressurizing channel (a); The screen tube (3) comprises a core shaft (32), an outer tube (31) and a reset mechanism. The outer tube (31) is provided with a second production channel (c) and a second pressurizing channel which are not connected to each other. The second production channel (c) is connected to the first production channel (b), and the second pressurizing channel is connected to the pressure transmission tube (4). The outer tube (31) is also provided with a first guide channel (d) which is connected to its inner wall and its outer wall. The core shaft (32) is located in the outer tube (31) and is connected to the second production channel (c). The core shaft (32) is also provided with a second guide channel (e) which is connected to its inner wall and its outer wall. A pressurizing chamber (g) and an air chamber (h) which are axially spaced apart are formed between the core shaft (32) and the outer tube (31). The pressurizing chamber (g) can be connected to the second pressurizing channel and push the core shaft (32) downward in the axial direction when pressurized. Air is enclosed in the air chamber (h). The reset mechanism can make the spindle (32) move upward, and provide two different travel end points for two adjacent upward movements of the spindle (32), the two travel end points being respectively a first end point and a second end point; when the spindle (32) moves to the first end point, the second guide channel (e) is connected to the first guide channel (d); when the spindle (32) moves to the second end point, the second guide channel (e) is staggered with the first guide channel (d).

2. The packer-screen assembly according to claim 1, characterized in that: The reset mechanism comprises a displacement sleeve (34), a pin shaft (35) and a reset spring (33); the displacement sleeve (34) is sleeved on the spindle (32) and axially limited with the spindle (32); a displacement groove (341) is provided on the displacement sleeve (34); one end of the pin shaft (35) is fixedly connected to the outer cylinder (31), and the other end is inserted into the displacement groove (341); one end of the reset spring (33) is in contact with the spindle (32), and the other end is in contact with the outer cylinder (31); The transposition groove (341) is formed by connecting a first Y-shaped groove and a second Y-shaped groove which are arranged alternately in the circumferential direction. The first Y-shaped groove and the second Y-shaped groove both include a first branch (3411), a second branch (3412) and a third branch (3413). The first branch (3411) extends along the axial direction of the transposition sleeve (34). The second branch (3412) and the third branch (3413) are both arranged in an L shape and are connected to the first branch (3411). One end of the second branch (3412) connected to the first branch (3411) extends along the axial direction of the transposition sleeve (34). The other end of the second branch (3412) is inclined in a direction away from the third branch (3413). The third branch (3413) is connected to the first branch (3411). One end of the connection is inclined in a direction away from the first branch (3411), and the other end of the third branch (3413) extends along the axial direction of the transposition sleeve (34), and the second branch (3412) and the third branch (3413) of the adjacent first Y-shaped groove and the second Y-shaped groove are connected, and the length of the first branch (3411) of the first Y-shaped groove is less than the length of the first branch (3411) of the second Y-shaped groove, and the end of the first branch (3411) of the second Y-shaped groove away from the second branch (3412) and the third branch (3413) is the second end point, and the end of the first branch (3411) of the first Y-shaped groove away from the second branch (3412) and the third branch (3413) is the first end point.

3. The packer-screen assembly according to claim 2, characterized in that: The outer tube (31) comprises an upper joint (311), a lower joint (313) and a cylinder (312); the front end of the upper joint (311) is connected to the packer (2); the rear end of the upper joint (311) is inserted into the cylinder (312) and connected to the cylinder (312); the front end of the lower joint (313) is inserted into the cylinder (312) and connected to the cylinder (312).

4. The packer-screen assembly according to claim 3, characterized in that: The upper joint (311) comprises a fixed joint (3111), a protection joint (3113), a shear joint (3112) and a rupture disk joint (3114); the fixed joint (3111) is connected to the packer (2); the shear joint (3112) and the protection joint (3113) are respectively sealed and connected to the inner side and the outer side of the fixed joint (3111); the front end of the mandrel (32) is inserted into the shear joint (3112); the shear joint (3112) and the protection joint (3113) are enclosed to form an annular space (f); the front end of the rupture disk joint (3114) is clamped between the shear joint (3112) and the protection joint (3113) and is sealed and connected to the shear joint (3112) and the protection joint (3113); the rear end of the rupture disk joint (3114) is clamped between the shear joint (3112) and the protection joint (3113); The core shaft (32) and the outer cylinder (31) are sealed and connected to each other. The rupture disk joint (3114), the shear joint (3112) and the core shaft (32) together enclose the pressurized chamber (g). The air chamber (h) is formed by the rupture disk joint (3114) and the core shaft (32). The rupture disk (3115) is arranged in a mounting hole provided in the rupture disk joint (3114). Both sides of the mounting hole correspond to the pressurized chamber (g) and the annular space (f) respectively. A connecting channel (i) is provided in the fixed joint (3111). One end of the connecting channel (i) is connected to the pressure transmission pipe (4), and the other end is connected to the annular space (f). The annular space (f), the connecting channel (i) and the mounting hole together constitute the second pressurized channel.

5. The packer-screen assembly according to claim 4, characterized in that: The spindle (32) is provided with a first stop ring (3221) and a second stop ring (3222) at intervals along the axial direction, and the displacement sleeve (34) is sleeved on the spindle (32) and is located between the first stop ring (3221) and the second stop ring (3222).

6. The packer-screen assembly according to claim 5, characterized in that: The spindle (32) is arranged in sections, including a power shaft section (321) and a reset shaft section (322) connected in the axial direction, the pressurized chamber (g) and the air chamber (h) are formed by enclosing the power shaft section (321) and the outer cylinder (31), and the second guide channel (e), the first retaining ring (3221) and the second retaining ring (3222) are arranged on the reset shaft section (322).

7. The packer-screen assembly according to claim 4, characterized in that: The connecting channel (i) comprises a radial channel and an axial channel, one end of the radial channel passes through the wall of the fixed joint (3111) and is sealed with a wire plug (11), the other end of the radial channel is connected to the pressure transmission pipe (4), one end of the axial channel is connected to the radial channel, and the other end is connected to the annular space (f).

8. The packer-screen assembly according to claim 1, characterized in that: A rupture disk (3115) is disposed in the second pressurizing channel.

9. The packer-screen assembly according to claim 1, characterized in that: A shear pin (36) is also provided between the core shaft (32) and the outer cylinder (31).

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