Mechanical packer for water injection well

Abstract

The mechanical packer for the water injection well comprises a circular-tube-shaped central tube, the upper end and the lower end of the central tube are in threaded connection with an upper connector and a lower connector respectively, and a backwashing valve is installed at the bottom of the upper connector. A sealing mechanism, a seat sealing mechanism and a friction reversing mechanism are sequentially sleeved on the central pipe between the backwashing valve and the lower joint from top to bottom, a backwashing seat for expanding the sealing mechanism is arranged at the bottom of the backwashing valve, and a cone for clamping the sleeve by the seat sealing mechanism is arranged at the bottom of the sealing mechanism; the outer side wall of the lower portion of the center pipe is provided with a plurality of pin guide grooves distributed in an annular array, and guide pins in sliding fit with the pin guide grooves are arranged in the friction reversing mechanism. The utility model has the beneficial effects that the risk of midway setting is avoided; deblocking of the packer is prevented from being affected by well leaving time and water injection pressure, and it is guaranteed that the packer can be deblocked smoothly; the packer is prevented from moving to the tubular column during water injection; and blockage caused by scaling within a short time of water injection can be prevented.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of packer, especially a mechanical packer for water injection well. BACKGROUND

[0002] The packer refers to the downhole tool connected to the downhole string, used for sealing the annular space of the oil tube and the casing or the open hole wall of the oil and gas well.

[0003] 1. The existing water injection packer is sealed by the pressure difference in the oil tube, which has the risk of sealing in the middle;

[0004] 2. The unsealing force of the existing water injection packer is greatly affected by the well retention time and the water injection pressure, and the unsealing load is high, which may cause the failure to unseal and lead to overhaul;

[0005] 3. The existing water injection packer has no slip, and has no anchoring effect on the casing after sealing, and the pressure fluctuation during water injection may cause the risk of pipe string movement;

[0006] 4. The existing water injection packer has a small water injection channel, which is easy to form blockage in a short time, affecting the water injection amount or not being able to inject water. INVENTION CONTENTS

[0007] The utility model aims at overcoming the above problems in the prior art, and provides a mechanical packer for water injection well.

[0008] In order to achieve the above technical purposes and effects, the utility model realizes the following technical scheme:

[0009] A mechanical packer for water injection well, comprising a center pipe in the shape of a circular tube, an upper joint and a lower joint are respectively screwed at the upper and lower ends of the center pipe, a backwashing valve is installed at the bottom of the upper joint, a sealing mechanism, a setting mechanism and a friction reversing mechanism are sequentially sleeved on the center pipe from top to bottom between the backwashing valve and the lower joint, a backwashing seat for expanding the sealing mechanism is arranged at the bottom of the backwashing valve, a cone for clamping the casing of the setting mechanism is arranged at the bottom of the sealing mechanism, a plurality of pin guide grooves arranged in a ring array are arranged on the outer side wall of the lower part of the center pipe, and a guide pin for sliding cooperation with the pin guide groove is arranged in the friction reversing mechanism.

[0010] The backwash valve comprises a backwash sleeve, a first compression spring, an inner piston, a backwash piston, a sealing nozzle, a sealing ring, a backwash seat and a rubber cylinder seat. The backwash sleeve is screwed with the lower part of the upper joint. The backwash seat is screwed with the lower part of the backwash sleeve. The first compression spring and the backwash piston are located between the upper joint and the backwash seat, and the first compression spring is clamped between the upper joint and the backwash piston. A plurality of water inlet holes arranged in a ring array are formed on the backwash sleeve at the junction of the backwash piston and the backwash seat. The inner piston is sleeved in the backwash piston. The sealing nozzle is screwed in the backwash piston. The sealing ring is clamped between the sealing nozzle and the backwash piston, and the bottom of the sealing ring is in abutment with the top of the backwash seat. The rubber cylinder seat is screwed at the bottom of the backwash seat. A plurality of water passing holes are formed on the sidewall of the lower part of the rubber cylinder seat.

[0011] The sealing mechanism comprises a rubber cylinder, a cone and a guide sleeve. The rubber cylinder is screwed at the top of the cone. The guide sleeve is screwed at the bottom of the cone. The outer side of the central pipe is provided with a support step for supporting the guide sleeve.

[0012] The central pipe, the backwash seat, the rubber cylinder seat and the cone form a ring-shaped water flow channel. A plurality of water outlet holes are formed on the cone and are in communication with the ring-shaped water flow channel.

[0013] The seat sealing mechanism comprises slips, a slip seat, a positioning sleeve and balls. The slip seat is screwed at the top of the positioning sleeve. The guide sleeve is sleeved in the slip seat. A plurality of slip installation grooves arranged in a ring array and arranged radially along the slip seat are formed on the slip seat. One slip is slidingly installed in each slip installation groove. A plurality of slip guide grooves arranged in a ring array are formed on the outer sidewall of the lower part of the cone. The slip and the slip guide groove are slidingly matched one by one. N ball containing holes arranged in a ring array are formed on the positioning sleeve. A circular ring-shaped ball track groove is formed on the outer sidewall of the central pipe. The balls are rotationally installed in the ball containing holes. When the seat sealing mechanism is in the unsealing state, the balls can roll along the ball track groove.

[0014] The friction reversing mechanism comprises a connecting sleeve, a check ring, a friction body, a friction block, a second compression spring, a guide pin and a cone cap. The lower part of the positioning sleeve is sleeved in the upper part of the connecting sleeve. The connecting sleeve is screwed with the top of the friction body. The cone cap is screwed with the bottom of the friction body. The upper part and the lower part of the friction body are respectively screwed with a check ring. A plurality of friction block containing grooves arranged in a ring array are formed on the outer side of the friction body. One friction block is contained in each friction block containing groove. A plurality of second compression springs are clamped between each friction block and the friction body. The upper and lower ends of the friction block are respectively located between the check ring and the friction body. The guide pin is screwed in the friction body.

[0015] The side wall of the lower part of the connecting sleeve is provided with a fan-shaped through hole.

[0016] The pin guiding groove is J-shaped, and the pin guiding groove comprises a short track, an inclined connecting track and a long track.

[0017] The utility model discloses beneficial effect is:

[0018] 1, need to lift, put down, rotate upper connector and center tube when seat seal, and make sealing mechanism and seat seal mechanism cooperate and realize seat seal under the auxiliary of friction mechanism, and the risk of seat seal in the middle way will not appear;

[0019] 2, only need to lift the upper connector, center tube when unsealing, drive backwash valve and sealing mechanism to move upwards, and the guide sleeve moves upwards to make the slip of seat seal mechanism gather to the direction of center axis, let the unsealing of packer avoid the influence of remaining well time and water injection pressure, guarantee that packer can unseal smoothly;

[0020] 3, utilize the slip of seat seal mechanism and anchor in the casing, prevent packer from producing channeling to pipe column when water injection;

[0021] 4, center tube and backwash seat, rubber cylinder seat, cone form a ring annular water flow channel, can prevent water injection and form the blockage of scale in short time. BRIEF DESCRIPTION OF DRAWINGS

[0022] The drawings explained here are used to provide further understanding of the utility model, and constitute a part of this application, and the illustrative embodiment of the utility model and its explanation are used to explain the utility model, and do not constitute improper limitation to the utility model. In the drawings:

[0023] Figure 1 It is the structure schematic diagram of mechanical packer in the utility model;

[0024] Figure 2 It is the structure schematic diagram of upper connector in the utility model;

[0025] Figure 3 It is the structure schematic diagram of backwash sleeve in the utility model;

[0026] Figure 4 It is the structure schematic diagram of inner piston in the utility model;

[0027] Figure 5 It is the structure schematic diagram of backwash piston in the utility model;

[0028] Figure 6 It is the structure schematic diagram of sealing nozzle in the utility model;

[0029] Figure 7 It is the structure schematic diagram of sealing ring in the utility model, and it is the structure schematic diagram of sealing ring in the utility model;

[0030] Figure 8 It is the structure schematic diagram of backwashing seat in the utility model, and it is the structure schematic diagram of backwashing seat in the utility model;

[0031] Figure 9 It is the structure schematic diagram of rubber cylinder seat in the utility model, and it is the structure schematic diagram of rubber cylinder seat in the utility model;

[0032] Figure 10 It is the structure schematic diagram of rubber cylinder in the utility model, and it is the structure schematic diagram of rubber cylinder in the utility model;

[0033] Figure 11 It is the structure schematic diagram of cone in the utility model, and it is the structure schematic diagram of cone in the utility model;

[0034] Figure 12 It is the structure schematic diagram of guide sleeve in the utility model, and it is the structure schematic diagram of guide sleeve in the utility model;

[0035] Figure 13 It is the structure schematic diagram of slip in the utility model, and it is the structure schematic diagram of slip in the utility model;

[0036] Figure 14 It is the structure schematic diagram of slip seat in the utility model, and it is the structure schematic diagram of slip seat in the utility model;

[0037] Figure 15 It is the structure schematic diagram of positioning sleeve in the utility model, and it is the structure schematic diagram of positioning sleeve in the utility model;

[0038] Figure 16 It is the structure schematic diagram of connecting sleeve in the utility model, and it is the structure schematic diagram of connecting sleeve in the utility model;

[0039] Figure 17 It is the structure schematic diagram of blocking ring in the utility model, and it is the structure schematic diagram of blocking ring in the utility model;

[0040] Figure 18 It is the structure schematic diagram of friction body in the utility model, and it is the structure schematic diagram of friction body in the utility model;

[0041] Figure 19 It is the structure schematic diagram of friction block in the utility model, and it is the structure schematic diagram of friction block in the utility model;

[0042] Figure 20 It is the structure schematic diagram of cone cap in the utility model, and it is the structure schematic diagram of cone cap in the utility model;

[0043] Figure 21 It is the structure schematic diagram of center tube in the utility model, and it is the structure schematic diagram of center tube in the utility model;

[0044] Figure 22 It is the structure schematic diagram of lower joint in the utility model, and it is the structure schematic diagram of lower joint in the utility model;

[0045] Explanation of reference numerals in the drawing: upper joint 1, backwashing sleeve 2, water inlet hole 201, first compression spring 3, inner piston 4, backwashing piston 5, sealing nozzle 6, sealing ring 7, backwashing seat 8, rubber sleeve seat 9, water passage hole 901, rubber sleeve 10, cone 11, water outlet hole 1101, slip guide groove 1102, guide sleeve 12, slip 13, slip seat 14, slip installation groove 1401, positioning sleeve 15, ball accommodating hole 1501, ball 16, connecting sleeve 17, through hole 1701, retaining ring 18, friction body 19, friction block accommodating groove 1901, friction block 20, spring accommodating groove 2001, second compression spring 21, guide pin 22, cone cap 23, central tube 24, pin guide groove 2401, short track 24011, communication track 24012, long track 24013, ball track groove 2402, support step 2403, lower joint 25. DETAILED DESCRIPTION

[0046] The utility model will be explained in detail below with reference to the drawings and in combination with the embodiments.

[0047] As Figures 1 to 22 shown in the figure, a mechanical packer for water injection well comprises a circular tube-shaped central tube 24, upper and lower heads of the central tube 24 are respectively screwed with an upper joint 1 and a lower joint 25, and the bottom of the upper joint 1 is provided with a backwashing valve.

[0048] The backwashing valve comprises a backwashing sleeve 2, a first compression spring 3, an inner piston 4, a backwashing piston 5, a sealing nozzle 6, a sealing ring 7, a backwashing seat 8, and a rubber sleeve seat 9, the backwashing sleeve 2 is screwed with the lower part of the upper joint 1, the backwashing seat 8 is screwed with the lower part of the backwashing sleeve 2, the first compression spring 3 and the backwashing piston 5 are located between the upper joint 1 and the backwashing seat 8, and the first compression spring 3 is clamped between the upper joint 1 and the backwashing piston 5; the inner piston 4 is sleeved in the backwashing piston 5, the sealing nozzle 6 is screwed in the backwashing piston 5, the sealing ring 7 is clamped between the sealing nozzle 6 and the backwashing piston 5, and the bottom of the sealing ring 7 abuts against the top of the backwashing seat 8; the rubber sleeve seat 9 is screwed at the bottom of the backwashing seat 8.

[0049] From top to bottom, the sealing mechanism, the seat sealing mechanism, and the friction reversing mechanism are sequentially sleeved on the central tube between the backwashing valve and the lower joint 25, the bottom of the backwashing valve is provided with the backwashing seat 8 for expanding the sealing mechanism, and the bottom of the sealing mechanism is provided with the cone 11 for clamping the seat sealing mechanism to the sleeve.

[0050] The sealing mechanism comprises the rubber sleeve 10, the cone 11, and the guide sleeve 12, the rubber sleeve 10 is screwed at the top of the cone 11, the guide sleeve 12 is screwed at the bottom of the cone 11, and the outer side of the central tube 24 is provided with the support step 2403 for supporting the guide sleeve. The top of the rubber sleeve 10 is internally conical, so that the rubber sleeve 10 has good expansion performance, and the sealing performance of the packer after setting is reliable.

[0051] The seat sealing mechanism comprises slips 13, slip seats 14, positioning sleeves 15, and balls 16, the slip seats 14 are screwed on the top of the positioning sleeves 15, and the guide sleeves 12 are sleeved in the slip seats 14; the slip seats 14 are provided with six slip installation grooves 1401 arranged in a ring array and along the radial direction of the slip seats 14, one slip 13 is slidingly installed in each slip installation groove, six slip guide grooves 1102 arranged in a ring array are formed on the outer side wall of the lower part of the cone 11, and the slip 13 slidingly matches the slip guide groove 1102.

[0052] Eight ball containing holes 1501 arranged in a ring array are formed on the positioning sleeve 15, a circular ball track groove 2402 is formed on the outer side wall of the central pipe 24, and the balls 16 are rotatably installed in the ball containing holes 1501.

[0053] When the seat sealing mechanism is in the unsealing state, one side of the ball 16 extends into the ball track groove 2402 and rolls along the ball track groove 2402; when the seat sealing mechanism is in the sealing state, the ball 16 is separated from the ball track groove 2402, so that the central pipe and the positioning sleeve can move along the axial direction of the central pipe.

[0054] The friction reversing mechanism comprises a connecting sleeve 17, a check ring 18, a friction body 19, friction blocks 20, second compression springs 21, guide pins 22, and a cone cap 23, the lower part of the positioning sleeve 15 is sleeved in the upper part of the connecting sleeve 17, the connecting sleeve 17 is screwed with the top of the friction body 19, the cone cap 23 is screwed with the bottom of the friction body 19, the upper part and the lower part of the friction body 19 are respectively screwed with a check ring 18, a plurality of friction block containing grooves 1901 arranged in a ring array are formed on the outer side of the friction body 19, one friction block 20 is contained in each friction block containing groove 1901, four second compression springs 21 are clamped between each friction block 20 and the friction body 19, the upper and lower heads of the friction block 20 are respectively located between the check ring 18 and the friction body 19, a plurality of spring containing grooves 2001 are formed on the centripetal side of the friction block 20, and one second compression spring 21 is installed in each spring containing groove 2001; the guide pins 22 are screwed in the friction body 19.

[0055] The outer side wall of the lower part of the central pipe 24 is provided with two pin guide grooves 2401 arranged in a ring array, and the friction reversing mechanism is provided with the guide pins 22 slidingly matched with the pin guide grooves 2401. Specifically, the pin guide groove 2401 is J-shaped, the pin guide groove 2401 comprises a short track 24011, an inclined communication track 24012, and a long track 24013, the short track 24011 and the long track 24013 are respectively parallel to the central axis of the central pipe 24, and the two ends of the communication track 24012 are respectively communicated with the bottom of the short track 24011 and the bottom of the long track 24013.

[0056] The water inlet holes 201 are arranged in a circular array on the reverse washing sleeve 2 at the junction of the reverse washing piston 5 and the reverse washing seat 8; the central tube 24, the reverse washing seat 8 and the rubber sleeve seat 9 and the cone 11 form a circular water flow channel, the side wall of the lower part of the rubber sleeve seat 9 is provided with a plurality of water passing holes 901, and the cone 11 is provided with a plurality of water outlet holes 1101 which are connected with the circular water flow channel.

[0057] When water injection, water flows into the gap between the reverse washing piston and the reverse washing seat through the water inlet holes, until the water pressure increases to lift the reverse washing piston 5 upward, so that the sealing ring 7 is separated from the reverse washing seat 8, and then the water flows into the circular water flow channel through the gap between the reverse washing seat and the reverse washing piston, the sealing ring and the sealing nozzle, and then flows to the lower part of the packer through the water passing holes 901 and the water outlet holes 1101.

[0058] The side wall of the lower part of the connecting sleeve 17 is provided with a fan-shaped through hole 1701 to prevent the gas or liquid in the enclosed area of the connecting sleeve 17, the central tube 24, the positioning sleeve 15 and the friction body 19 from being discharged normally.

[0059] The operation process of the packer:

[0060] Setting process: after the packer is lowered into the well according to the designed depth, the pipe string is lifted and rotated in the positive direction, so that the upper joint and the central tube are lifted and rotated in the positive direction, at this time the guide pin installed in the friction body leaves the short track and enters the long track; then the pipe string is lowered to lower the upper joint and the central tube, at this time the slips and the friction body remain stationary under the friction force of the friction block and the sleeve, the upper joint, the central tube and the reverse washing valve are lowered together to push the cone to open the slips and clamp the packer in the sleeve, and at the same time the reverse washing valve is closed, the rubber sleeve is compressed under the weight of the upper pipe string to increase the outer diameter of the rubber sleeve to seal the annular space between the packer and the sleeve.

[0061] Water injection process: after the packer is set, water is injected into the annular space of the sleeve, when the water pressure reaches 1Mpa, the reverse washing piston is lifted upward to open the reverse washing valve, and then the water flows into the circular water flow channel through the gap between the reverse washing seat and the reverse washing piston, the sealing ring and the sealing nozzle, and then flows to the lower part of the packer through the water passing holes and the water outlet holes, so that the water injection operation in the sleeve can be realized.

[0062] Unsetting process: the pipe string is lifted to make the upper joint, the central tube and the reverse washing valve move upward together, the reverse washing seat is pulled out of the rubber sleeve to restore the rubber sleeve, the cone is pulled out of the slip, the slip is gathered towards the central tube, the slip is separated from the sleeve, and the packer is unsetting.

[0063] The basic principle, main features and advantages of the present application are shown and described above. Those skilled in the art should understand that the present application is not limited by the above examples, and the above examples and descriptions in the specification are only to illustrate the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application.

Claims

1. A mechanical packer for use in a water injection well, characterized in that: The utility model provides a center tube of round pipe shape, the upper and lower heads of center tube are screwed with upper joint, lower joint respectively, the bottom of upper joint is equipped with backwash valve, the center tube between backwash valve and lower joint is successively sleeved with sealing mechanism, seat seal mechanism and friction reversing mechanism from top to bottom, the bottom of backwash valve is equipped with backwash seat for making sealing mechanism expand, the bottom of sealing mechanism is equipped with cone for making seat seal mechanism catch sleeve, the outside wall of lower part of center tube is equipped with a plurality of pin guide groove according to annular array arrangement, the friction reversing mechanism is equipped with guide pin that slides with pin guide groove.

2. The mechanical packer of claim 1, wherein: The backwash valve includes a backwash sleeve, a first compression spring, an inner piston, a backwash piston, a sealing nozzle, a sealing ring, a backwash seat, and a rubber cylinder seat. The backwash sleeve is screwed with the lower part of the upper joint. The backwash seat is screwed with the lower part of the backwash sleeve. The first compression spring and the backwash piston are located between the upper joint and the backwash seat, and the first compression spring is clamped between the upper joint and the backwash piston. A plurality of water inlet holes are arranged on the backwash sleeve at the junction of the backwash piston and the backwash seat in an annular array. The inner piston is sleeved in the backwash piston. The sealing nozzle is screwed in the backwash piston. The sealing ring is clamped between the sealing nozzle and the backwash piston, and the bottom of the sealing ring is in abutment with the top of the backwash seat. The rubber cylinder seat is screwed at the bottom of the backwash seat. A plurality of water passing holes are arranged on the side wall of the lower part of the rubber cylinder seat.

3. The mechanical packer of claim 2, wherein: The sealing mechanism includes a rubber cylinder, a cone, and a guide sleeve. The rubber cylinder is screwed at the top of the cone. The guide sleeve is screwed at the bottom of the cone. The outer side of the center tube is provided with a support step for supporting the guide sleeve.

4. The mechanical packer of claim 3, wherein: The center tube, the backwash seat, the rubber cylinder seat, and the cone form an annular water flow channel. A plurality of water outlet holes are arranged on the cone and communicate with the annular water flow channel.

5. The mechanical packer of claim 3, wherein: The seat seal mechanism includes a slip, a slip seat, a positioning sleeve, and a ball. The slip seat is screwed at the top of the positioning sleeve, and the guide sleeve is sleeved in the slip seat. A plurality of slip installation grooves are arranged on the slip seat in an annular array and radially along the slip seat. One slip is slidingly installed in each slip installation groove. A plurality of slip guide grooves are arranged on the outer side wall of the lower part of the cone in an annular array. The slip and the slip guide groove are slidingly matched one by one. N ball containing holes are arranged on the positioning sleeve in an annular array. A circular annular ball track groove is arranged on the outer side wall of the center tube. The ball is rotationally installed in the ball containing hole. When the seat seal mechanism is in the unsealing state, the ball can roll along the ball track groove.

6. The mechanical packer of claim 5, wherein: The friction gear shift mechanism comprises a connecting sleeve, a check ring, a friction body, a friction block, a second compression spring, a guide pin and a cone cap, the lower part of the locating sleeve is sleeved in the upper part of the connecting sleeve, the connecting sleeve is screwed with the top of the friction body, the cone cap is screwed with the bottom of the friction body, the upper and lower parts of the friction body are respectively screwed with a check ring, the outer side of the friction body is provided with a plurality of friction block accommodating grooves arranged in an annular array, each friction block accommodating groove accommodates a friction block, a plurality of second compression springs are clamped between each friction block and the friction body, the upper and lower ends of the friction block are respectively located between the check ring and the friction body, and the guide pin is screwed in the friction body.

7. The mechanical packer of claim 6, wherein: A fan-shaped annular through hole is formed in the side wall of the lower part of the connecting sleeve.

8. The mechanical packer of claim 1, wherein: The pin guide groove is J-shaped, and the pin guide groove comprises a short track, an inclined communication track and a long track, the short track and the long track are respectively parallel to the central axis of the center tube, and the two ends of the communication track are respectively communicated with the bottom of the short track and the bottom of the long track.

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