阅读说明：本技术 一种多胶筒串接式封隔器 (Multi-rubber-barrel tandem packer ) 是由 石建设 彭太祥 石易蕾 于 2021-10-18 设计创作，主要内容包括：本发明为多胶筒串接式封隔器,包括进液机构和封隔机构,进液机构包括上接头、筛套和连通接头；封隔机构包括连通接头、中心管、胶上护套、扩张短胶筒、胶下护套、上动护套和下接头；扩张短胶筒的下端与胶下护套螺纹连接形成胶筒连接结构,胶筒连接结构至少为两个,依次设置,相邻的胶筒连接结构中,位于上方的胶下护套与位于下方的扩张短胶筒之间设置有上动护套,中心管上对应上动护套的位置设置有异径环,异径环上设置有通槽、进口槽、周向槽和直槽,进口槽、周向槽和直槽依次设置,上动护套的内侧设置有导向键,导向键能够通过通槽、进口槽和周向槽进入直槽内。本发明的多胶筒串接式封隔器,提高了封隔器的承压能力。(The invention relates to a multi-rubber-barrel tandem packer, which comprises a liquid inlet mechanism and a packing mechanism, wherein the liquid inlet mechanism comprises an upper joint, a screen sleeve and a communicating joint; the packing mechanism comprises a communicating joint, a central pipe, an upper rubber sheath, an expansion short rubber cylinder, a lower rubber sheath, an upper movable sheath and a lower joint; the lower extreme of the short packing element of expansion and the short packing element of sheath threaded connection formation packing element connection structure under the glue, packing element connection structure is two at least, set gradually, among the adjacent packing element connection structure, be located the below the glue sheath and be located and be provided with the jacket that moves on between the short packing element of expansion of below, it is provided with the reducing ring to correspond the position of moving the sheath on the center tube, be provided with logical groove on the reducing ring, the import groove, circumference groove and straight flute set gradually, the inboard of moving the sheath on is provided with the feather key, the feather key can pass through logical groove, import groove and circumference groove get into in the straight flute. The multi-rubber-cylinder serial packer improves the pressure bearing capacity of the packer.)

1. A multi-rubber-barrel tandem packer comprises a liquid inlet mechanism and a packing mechanism, and is characterized in that,

the liquid inlet mechanism comprises an upper joint, a screen sleeve and a communicating joint, the lower end of the upper joint is in threaded connection and sealed connection with the upper end of the communicating joint, and the screen sleeve is located inside the upper joint and the communicating joint and is respectively in sealed connection and sliding connection with the upper joint and the communicating joint;

the packing mechanism comprises a communicating joint, a central pipe, an upper rubber sheath, an expansion short rubber cylinder, a lower rubber sheath, an upper movable sheath and a lower joint;

the lower end of the communicating joint is sleeved at the upper end of the central pipe and is in threaded connection and sealing connection with the central pipe;

the upper end of the rubber upper sheath is sleeved at the lower end of the communicating joint and is in threaded connection and sealing connection with the communicating joint;

the lower ends of the expansion short rubber cylinders are in threaded connection with the lower rubber sleeve to form rubber cylinder connecting structures, the rubber cylinder connecting structures are at least two and are sequentially arranged, an upper movable sheath is arranged between the lower rubber sleeve positioned above and the expansion short rubber cylinder positioned below in the adjacent rubber cylinder connecting structures and is sleeved on the central tube, the top ends of the upper movable sheaths are in sealed connection and slide rotation with the lower ends of the corresponding lower rubber sleeves, and the lower ends of the upper movable sheaths are in threaded connection with the upper ends of the corresponding expansion short rubber cylinders; the upper end of the expansion short rubber cylinder at the top end is in threaded connection with the lower end of the rubber jacket;

the lower joint is in threaded connection with the lower end of the central pipe, is in sealed connection with the lower end of the lower rubber jacket at the bottom end, and slides and rotates;

the position that corresponds on the center tube and move the sheath on is provided with the reducing ring, be provided with logical groove, import groove, circumference groove and straight flute on the reducing ring, import groove, circumference groove and straight flute set gradually, the inboard that moves the sheath on is provided with the guide key, the guide key can pass through logical groove, import groove and circumference groove get into in the straight flute.

2. The multi-packer tandem packer of claim 1, wherein the length of the straight groove is greater than the length of the guide key.

3. The multi-packer tandem packer of claim 1, wherein the through groove, the inlet groove, and the straight groove are disposed perpendicular to the circumferential groove, the inlet groove and the straight groove being located at both ends of the circumferential groove;

the circumferential groove is perpendicular to the axis of the center tube.

4. The multi-packer tandem packer of claim 1 or 3, wherein the through groove is located on one side of the base pipe and the inlet groove, circumferential groove and straight groove are located on the other side of the base pipe.

5. The multi-packer tandem packer of claim 1, 3 or 4, wherein the inlet groove is located at a bottom end of the reducing ring, and the guide key has a length less than a width of the circumferential groove.

6. A multi-rubber-barrel tandem packer comprises a liquid inlet mechanism and a packing mechanism, and is characterized in that,

the liquid inlet mechanism comprises an upper joint, a screen sleeve and a double-control reversing valve, the lower end of the upper joint is in threaded connection and sealed connection with the upper end of the double-control reversing valve, and the screen sleeve is located inside the upper joint and the double-control reversing valve and is respectively in sealed connection and sliding connection with the upper joint and the double-control reversing valve;

the packing mechanism comprises a double-control reversing valve, a central pipe, an upper rubber sheath, a short expansion rubber cylinder, a lower rubber sheath, an upper movable sheath and a lower joint;

the lower end of the double-control reversing valve is sleeved at the upper end of the central pipe and is in threaded connection and sealing connection with the central pipe;

the upper end of the upper sheath is sleeved at the lower end of the double-control reversing valve and is in threaded connection and sealing connection with the double-control reversing valve.

7. A packer with multiple rubber cylinders connected in series comprises a liquid inlet mechanism and a packing mechanism, and is characterized in that the liquid inlet mechanism comprises an upper joint, a screen sleeve and a communicating joint, the lower end of the upper joint is in threaded connection and sealed connection with the upper end of the communicating joint, and the screen sleeve is positioned inside the upper joint and the communicating joint and respectively in sealed connection and sliding connection with the upper joint and the communicating joint;

the packing mechanism comprises a communicating joint, a central pipe, an upper rubber sheath, an expansion short rubber cylinder, a lower rubber sheath, an upper movable sheath and a lower joint;

the lower end of the communicating joint is sleeved at the upper end of the central pipe and is in threaded connection and sealing connection with the central pipe;

the upper end of the rubber upper sheath is sleeved at the lower end of the communicating joint and is in threaded connection and sealing connection with the communicating joint;

the lower ends of the expansion short rubber cylinders are in threaded connection with the lower rubber sleeve to form rubber cylinder connecting structures, the rubber cylinder connecting structures are at least two and are sequentially arranged, an upper movable sheath is arranged between the lower rubber sleeve positioned above and the expansion short rubber cylinder positioned below in the adjacent rubber cylinder connecting structures and is sleeved on the central tube, the top ends of the upper movable sheaths are in sealed connection and slide rotation with the lower ends of the corresponding lower rubber sleeves, and the lower ends of the upper movable sheaths are in threaded connection with the upper ends of the corresponding expansion short rubber cylinders; the upper end of the expansion short rubber cylinder at the top end is in threaded connection with the lower end of the rubber jacket;

the lower joint is in threaded connection with the lower end of the central pipe, is in sealed connection with the lower end of the lower rubber jacket at the bottom end, and slides and rotates;

the central tube is provided with a reducing ring at a position corresponding to the upper moving sheath, the reducing ring is provided with a through groove and a non-through groove, the through groove is intersected with the non-through groove along the circumferential spiral of the reducing ring, the inner side of the upper moving sheath is provided with a guide key, and the guide key can enter the non-through groove through the through groove.

8. The multi-packer tandem packer of claim 7, wherein the pilot key is capable of passing through the through-going groove from one end of the reducing ring to the upper end of the reducing ring or the pilot key is capable of passing through the through-going groove from the upper end of the reducing ring to the lower end of the reducing ring;

the length of the diagonal line of the guide key is smaller than the width of the through groove and the width of the non-through groove;

the cross section of the guide key on the inner side of the upper movable sheath can be rectangular, circular, square, trapezoidal or polygonal.

9. The multi-packer tandem packer of claim 7 or 8, wherein the blind groove is a straight groove parallel to the axis of the reducing ring or a spiral groove that is raised in the circumferential direction.

10. The multi-packing-drum tandem packer according to claim 7 or 8, wherein one end of the reducing ring is an upper end of the reducing ring, and the other end is a lower end of the reducing ring, or,

one end of the reducing ring is the lower end of the reducing ring, and the other end of the reducing ring is the upper end of the reducing ring.

Technical Field

The invention belongs to the technical field of petroleum exploitation machinery, and relates to a multi-rubber-cylinder tandem packer.

Background

At present, packers mainly adopted by a layered water injection well of an oil field are mainly of types of Y341, K344 and the like, and are realized by adopting modes of double rubber cylinders, lengthened rubber cylinders and the like in order to adapt to a thin-interlayer oil reservoir and improve the sealing effect; the packer comprises a packer with a washable and airtight long rubber cylinder (application No. 201720652446.1), a packer with a long rubber cylinder (application No. 201821993373.3) capable of being repeatedly set, a combined packer with double rubber cylinders and an open hole (201810845933.9), and the like, wherein the packer is provided with an expansion type long rubber cylinder; the use effect of the packer mainly depends on the performance index of the long rubber cylinder, the pressure bearing surface in the lengthened rubber cylinder is increased, 2-3 layers of steel wire cords are added in the rubber cylinder for improving the pressure bearing capacity, the manufacturing process difficulty is increased, the sealing length of the common long rubber cylinder is required to reach 0.8-1.2 m, the price is high, the lengthened rubber cylinder has unstable processing quality, and the underground use effect difference of various long rubber cylinder packers is great.

Disclosure of Invention

The invention aims to provide a packer with multiple rubber cylinders connected in series, so as to solve at least one technical problem.

One technical scheme of the application is as follows: a multi-rubber-barrel tandem packer comprises a liquid inlet mechanism and a packing mechanism, wherein the liquid inlet mechanism comprises an upper joint, a screen sleeve and a communicating joint, the lower end of the upper joint is in threaded connection and sealed connection with the upper end of the communicating joint, and the screen sleeve is positioned inside the upper joint and the communicating joint and is respectively in sealed connection and sliding connection with the upper joint and the communicating joint; the packing mechanism comprises a communicating joint, a central pipe, an upper rubber sheath, an expansion short rubber cylinder, a lower rubber sheath, an upper movable sheath and a lower joint; the lower end of the communicating joint is sleeved at the upper end of the central pipe and is in threaded connection and sealing connection with the central pipe; the upper end of the rubber upper sheath is sleeved at the lower end of the communicating joint and is in threaded connection and sealing connection with the communicating joint; the lower ends of the expansion short rubber cylinders are in threaded connection with the lower rubber sleeve to form rubber cylinder connecting structures, the rubber cylinder connecting structures are at least two and are sequentially arranged, an upper movable sheath is arranged between the lower rubber sleeve positioned above and the expansion short rubber cylinder positioned below in the adjacent rubber cylinder connecting structures and is sleeved on the central tube, the top ends of the upper movable sheaths are in sealed connection and sliding connection with the lower ends of the corresponding lower rubber sleeves, and the lower ends of the upper movable sheaths are in threaded connection with the upper ends of the corresponding expansion short rubber cylinders; the upper end of the expansion short rubber cylinder at the top end is in threaded connection with the lower end of the rubber jacket; the lower joint is in threaded connection with the lower end of the central pipe and is in sealing connection with the lower end of the lower rubber jacket at the bottom end; the position that corresponds on the center tube and move the sheath on is provided with the reducing ring, be provided with logical groove, import groove, circumference groove and straight flute on the reducing ring, import groove, circumference groove and straight flute set gradually, the inboard that moves the sheath on is provided with the guide key, the guide key can pass through logical groove, import groove and circumference groove get into in the straight flute.

Preferably, the length of the straight groove is greater than the length of the guide key.

Preferably, the through groove, the inlet groove and the straight groove are arranged perpendicular to the circumferential groove, and the inlet groove and the straight groove are positioned at two ends of the circumferential groove; the circumferential groove is perpendicular to the axis of the center tube.

Preferably, the through slot is located on one side of the central tube, and the inlet slot, the circumferential slot and the straight slot are located on the other side of the central tube.

Preferably, the inlet groove is located at a bottom end of the reducing ring.

Another technical scheme of the application is as follows: a packer with multiple rubber cylinders connected in series comprises a liquid inlet mechanism and a packing mechanism, wherein the liquid inlet mechanism comprises an upper joint, a screen sleeve and a double-control reversing valve, the lower end of the upper joint is in threaded connection and sealed connection with the upper end of the double-control reversing valve, and the screen sleeve is located inside the upper joint and the double-control reversing valve and respectively in sealed connection and sliding connection with the upper joint and the double-control reversing valve; the packing mechanism comprises a double-control reversing valve, a central pipe, an upper rubber sheath, a short expansion rubber cylinder, a lower rubber sheath, an upper movable sheath and a lower joint; the lower end of the double-control reversing valve is sleeved at the upper end of the central pipe and is in threaded connection and sealing connection with the central pipe; the upper end of the glue sheath is sleeved at the lower end of the double-control reversing valve and is in threaded connection and sealing connection with the double-control reversing valve; the lower ends of the expansion short rubber cylinders are in threaded connection with the lower rubber sleeve to form rubber cylinder connecting structures, the rubber cylinder connecting structures are at least two and are sequentially arranged, an upper movable sheath is arranged between the lower rubber sleeve positioned above and the expansion short rubber cylinder positioned below in the adjacent rubber cylinder connecting structures and is sleeved on the central tube, the top ends of the upper movable sheaths are in sealed connection and sliding connection with the lower ends of the corresponding lower rubber sleeves, and the lower ends of the upper movable sheaths are in threaded connection with the upper ends of the corresponding expansion short rubber cylinders; the upper end of the expansion short rubber cylinder at the top end is in threaded connection with the lower end of the rubber jacket; the lower joint is in threaded connection with the lower end of the central pipe and is in sealing connection with the lower end of the lower rubber jacket at the bottom end; the position of the central tube corresponding to the upper moving sheath is provided with a reducing ring 9-1, the reducing ring is provided with a through groove, an inlet groove, a circumferential groove and a straight groove, the inlet groove, the circumferential groove and the straight groove are sequentially arranged, the inner side of the upper moving sheath is provided with a guide key 14-1, and the guide key can enter the straight groove through the through groove, the inlet groove and the circumferential groove.

Preferably, the length of the straight groove is greater than the length of the guide key.

Preferably, the through groove, the inlet groove and the straight groove are arranged perpendicular to the circumferential groove, and the inlet groove and the straight groove are positioned at two ends of the circumferential groove; the circumferential groove is perpendicular to the axis of the center tube.

Preferably, the through slot is located on one side of the central tube, and the inlet slot, the circumferential slot and the straight slot are located on the other side of the central tube.

Preferably, the inlet groove is located at a bottom end of the reducing ring.

The application provides a many packing elements tandem type packer has following advantage:

the ingenious suspension structure design of the multiple rubber cylinders ensures that the working state of the original single rubber cylinder is kept when the multiple rubber cylinders are seated and sealed, and the practicability and reliability of the mature structure are fully exerted; in addition, in the process of setting, the expansion rubber sleeve moves in the circumferential direction when being extruded by liquid, and the guide key can slide in the straight groove, so that the expansion rubber sleeve can move slightly in the axial direction, the forced stretching of the expansion rubber sleeve by the liquid pressure is relieved, and the pressure bearing capacity of the packer is improved.

Drawings

FIG. 1 is a schematic diagram of the overall structure of a multi-packer-tube tandem type packer of the present application,

wherein, for the convenience of magnifying observation, the whole structure is divided into 3 segments for representation;

FIG. 2 is a schematic structural view of a center tube;

FIG. 3 is a cross-sectional view A-A of FIG. 2;

FIG. 4 is a schematic view of a portion of another multi-packer of the present invention;

FIG. 5 is a schematic structural view of a reducing ring;

reference numbers in the figures: an upper joint 1, a first O-shaped sealing ring 2, a screen jacket 3, a second O-shaped sealing ring 4, a communicating joint 5, a fourth O-shaped sealing ring 6, a third O-shaped sealing ring 7, a fifth O-shaped sealing ring 8, a central pipe 9, a reducing ring 9-1, an inlet groove 9-2, a circumferential groove 9-3, a straight groove 9-4, a through groove 9-5, an upper rubber jacket 10, an expansion short rubber cylinder 11 and a lower rubber jacket 12, a sixth O-shaped sealing ring 13, a seventh O-shaped sealing ring 13a, an upper movable sheath 14, a guide key 14-1, a lower connector 15, a double-control reversing valve 17, a choke plug 17-1, a plug rod 17-2, an eighth O-shaped sealing ring 17-3, a valve body 17-4, a valve ball 17-5, a ball support 17-6, a spring 17-7, a guide cap 17-8, a non-through groove 9-6 and a through groove 9-7.

Detailed Description

The invention is further illustrated by the following figures and examples.

It should be noted that the positions of the upper end, the lower end, the top end, the bottom end and the like mentioned in the present application are based on the using state of the device, and the positions are all well known to those skilled in the art.

Example 1: the application provides a multi-rubber-barrel tandem packer, which comprises a liquid inlet mechanism and a packing mechanism, wherein the liquid inlet mechanism comprises an upper joint 1, a screen sleeve 3 and a communicating joint 5, the lower end of the upper joint is in threaded connection and sealing connection with the upper end of the communicating joint, and a fourth O-shaped sealing ring 6 is arranged between the general upper joint and the communicating joint to realize sealing connection; the screen sleeve is positioned in the upper joint and the communicating joint and is respectively connected with the upper joint and the communicating joint in a sealing and sliding way, generally, a first O-shaped sealing ring 2 is arranged between the screen sleeve and the upper joint to realize sealing connection, and a second O-shaped sealing ring 4 is arranged between the screen sleeve and the communicating joint to realize sealing connection; the packing mechanism comprises a communicating joint, a central pipe 9, an upper rubber sheath 10, an expansion short rubber barrel 11, a lower rubber sheath 12, an upper movable sheath 14 and a lower joint 15; the lower end of the communicating joint is sleeved at the upper end of the central pipe, is in threaded connection and sealed connection with the central pipe, and a third O-shaped sealing ring 7 is generally arranged between the communicating joint and the central pipe to realize sealed connection; the upper end of the glue jacket is sleeved at the lower end of the communicating joint, is in threaded connection and sealing connection with the communicating joint, and a fifth O-shaped sealing ring 8 is arranged between the glue jacket and the communicating joint to realize sealing connection; the lower ends of the expansion short rubber cylinders are in threaded connection with the lower rubber sleeve to form rubber cylinder connecting structures, the rubber cylinder connecting structures are at least two and are sequentially arranged, in the adjacent rubber cylinder connecting structures, an upper movable sheath 14 is arranged between the lower rubber sleeve positioned above and the expansion short rubber sleeve positioned below, the upper movable sheath is sleeved on the central tube, the top end of the upper movable sheath is in sealed connection and sliding connection with the lower end of the corresponding lower rubber sleeve, generally, a sixth O-shaped sealing ring 13 is arranged between the upper movable sheath and the corresponding lower rubber sleeve to realize sealed connection, and the lower end of the upper movable sheath is in threaded connection with the upper end of the corresponding expansion short rubber sleeve; the upper end of the expansion short rubber cylinder at the top end is in threaded connection with the lower end of the rubber jacket; the lower joint is in threaded connection with the lower end of the central pipe, is in sealing connection with the lower end of the lower rubber jacket at the bottom end, and is in sliding and rotating connection, in this embodiment, the sliding and rotating connection can be in clearance fit, and generally, a seventh O-shaped sealing ring 13a is arranged between the lower joint and the lower rubber jacket at the bottom end to realize sealing connection; the central tube is provided with a reducing ring 9-1 corresponding to the upper moving sheath, the reducing ring is provided with a through groove 9-5, an inlet groove 9-2, a circumferential groove 9-3 and a straight groove 9-4, the inlet groove 9-2, the circumferential groove 9-3 and the straight groove 9-4 are sequentially arranged from the bottom end to the top end of the reducing ring, the inner side of the upper moving sheath is provided with a guide key 14-1, and the guide key can pass through the through groove and can enter the straight groove through the inlet groove and the circumferential groove in sequence.

In the above embodiments, the through groove is a groove penetrating through the upper end and the lower end of the reducing ring, the inlet groove is a groove located at the bottom end or the top end of the reducing ring, the circumferential groove is a section of groove arranged along the circumferential direction of the reducing ring, the straight groove is a vertically arranged groove, the length is generally slightly greater than that of the guide key, generally, the through groove is located on one side of the central tube, and the inlet groove, the circumferential groove and the straight groove are located on the other side of the central tube. When the sheath is installed, the guide key 14-1 passes through the reducing ring 9-1 at the lower end from the through groove 9-5 at the lower end of the central tube 9, enters the straight groove 9-4 from the inlet groove 9-2 and the circumferential groove 9-3, and is hung on the central tube 9, and the plurality of rubber cylinders are skillfully designed in a hanging structure, so that the working state of the original single rubber cylinder is kept when the plurality of rubber cylinders are sealed, and the practicability and reliability of a mature structure are fully exerted; in addition, in the process of setting, the expansion rubber sleeve moves in the circumferential direction when being extruded by liquid, and the guide key can slide in the straight groove, so that the expansion rubber sleeve can slightly move in the axial direction, the forced stretching of the liquid pressure to the expansion rubber sleeve is slowed down, and the pressure bearing capacity of the packer is improved; it should be noted that fig. 1 of the present invention shows a structural design diagram for suspending 4 rubber cylinder connection structures (which may also be referred to as sealing units), and similarly, 1 rubber cylinder connection structure is suspended in a double-cylinder serial manner, 2 rubber cylinder connection structures are suspended in a 3-cylinder serial manner, … and so on, and a plurality of rubber cylinder connection structures can be suspended according to the field requirement without being limited by the length of a long rubber cylinder to the performance requirement;

example 2: the structure of the embodiment 2 is substantially the same as that of the embodiment 1, and the difference is that the double-control reversing valve 17 replaces the communication joint 5, referring to fig. 4, so that the function of the packer can be increased, the interlayer channeling prevention capability of the packer can be improved, the stability of stratified injection can be improved, and the separate injection efficiency can be improved, in the embodiment, the double-control reversing valve comprises a plug 17-1, a plug rod 17-2, an eighth O-shaped sealing ring 17-3, a valve body 17-4, a valve ball 17-5, a ball support 17-6, a spring 17-7 and a diversion cap 17-8, wherein the valve body is provided with an upper deviation hole and a lower deviation hole, the upper deviation hole is communicated with the lower deviation hole through a communication hole, the plug rod is sleeved with the eighth O-shaped sealing ring 17-3 and is positioned in the upper deviation hole, and the top end of the plug rod is contacted with the plug 17-1; and a valve ball 17-5, a ball support 17-6 and a spring 17-7 are sequentially arranged in the lower inclined hole, the bottom end of the plug rod is connected with the ball valve, and the bottom end of the lower inclined hole is in threaded connection with a flow guide cap 17-8. When the structure is used, the packer is pressurized, namely, set, the valve ball 17-5 is closed to form self-locking after pressure relief, when the external acting force of the plug rod 17-2 is greater than the self-locking internal cavity pressure acting on the thrust of the valve ball 17-5, the valve ball 17-5 is ejected to release pressure, and the packer is unsealed.

Working example: the two-stage three-section separate injection pipe column comprises an oil pipe, an integrated packing water distributor, the single-layer water distributor, the oil pipe, a fixed valve, a sieve pipe, a pipe plug and the like, the two-stage three-section separate injection pipe column is connected by the oil pipe and sequentially goes into a well, and when the inside of the oil pipe is pressurized, the three-stage three-section separate injection pipe column and the packer complete seat sealing. When the well is washed back, when the casing pressure is larger than a certain value of oil pressure, the packer and the invention are unsealed, and the well washing liquid enters the pipe from the screen pipe at the bottom of the pipe column and the fixed valve to the well mouth: when the pipe string is lifted in operation, the oil pipe is firstly decompressed, namely the packer and the invention are unsealed, and the oil pipe, the invention and all the well entering tools are taken out from the well in sequence.

Example 3: embodiment 3 is substantially the same as embodiment 1, except that the reducing ring has a different structure, specifically, referring to fig. 3, the reducing ring is provided with a through groove 9-7 and an blind groove 9-6, the through groove spirally intersects with the blind groove along the circumferential direction of the reducing ring, the inner side of the upper movable sheath is provided with a guide key, the guide key can enter the blind groove through the through groove, in this embodiment, the blind groove is a straight groove parallel to the axis of the reducing ring or a spiral groove spirally lifted along the circumferential direction, the guide key can pass through the through groove from the lower end of the reducing ring to the upper end of the reducing ring, and the guide key can also pass through the through groove from the upper end of the reducing ring to the lower end of the reducing ring; the length of the diagonal line of the guide key is smaller than the width of the through groove and the width of the non-through groove; the section shape of the guide key on the inner side of the upper moving sheath can be rectangular, circular, square, trapezoidal or other polygons, and the structure is more convenient for the installation of the packer.

The above description is only for the purpose of illustrating preferred embodiments of the present invention and is not to be construed as limiting the present invention, and the terms first, second, etc. are used for distinguishing between similar terms and not for limiting the technical terms, and various modifications and variations of the present invention may occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.