A precision cement plugging device with electronic control for well workover operations

Abstract

This utility model discloses an electrically controlled precision cement plugging device for well workover operations, comprising a valve body with an equipment placement section; an equipment groove on the outer wall of the equipment placement section and a slide rail communicating with the equipment groove on the inner wall of the equipment placement section; a drive device in the equipment groove and a valve plate in the slide rail; the valve plate and the output shaft of the drive device are connected via a transmission mechanism; the drive device causes the valve plate to slide along the slide rail; and a plug core is placed above the valve plate inside the equipment placement section. This utility model reduces the labor intensity of operators, eliminates the need for backwashing operations, reduces oil layer contamination, avoids the generation of cement slag, and can achieve both solid and suspended plugs. It has a large single-use slurry capacity, capable of completing 30m of cement injection in one operation. Compared with conventional cement plugging operations, this device does not require the insertion of tubing; only a rapid sand dredging machine and cement injection tools are needed to complete the operation, significantly shortening the operation time per well.

Description

Technical Field

[0001] This utility model relates to the field of well workover equipment technology, specifically to an electrically controlled precision cement plugging device for well workover operations. Background Technology

[0002] Currently, with the increasing service years of oil and gas wells and the gradual decrease in downhole oil and gas resources, the demand for well workover operations is growing. When the reserves of a certain oil layer downhole are gradually depleted, while nearby oil layers still have some reserves, it is necessary to plug the currently exploited oil layer before opening a new oil layer for production. When plugging an existing oil layer, slurry is generally delivered to the oil layer depth, the slurry injection tool is removed, and the plugging effect is achieved after the slurry solidifies. Existing wellbore local plugging technologies include cement plugging and packer methods. The packer method is suitable for short-term or temporary plugging, and the packer can be removed later. The cement plugging method is suitable for permanent plugging and is mainly used for local lost circulation zones or formations that have no exploitable value.

[0003] Currently, there are two main cement plugging techniques: conventional tubing tripping and wire rope rapid workover. Tubing tripping suffers from high labor intensity and low efficiency. While wire rope rapid workover significantly improves efficiency, the wire rope can only perform the operation through a "lifting and lowering" motion. With the development of new technologies and tools, wire rope cannot be used with downhole electric tools. Furthermore, this technique is affected by factors such as tubing weight, well fluid density, and wire rope elongation, resulting in a measurement error of 1.5-3‰ or more. Due to depth errors, it cannot be used for wells requiring precise depth, such as those with thin interlayers or small pockets. Therefore, neither of these methods can quickly and efficiently solve on-site problems.

[0004] Publication No. CN118008196A discloses a slurry emptying cylinder and slurry emptying method for a small-diameter oil pipe. A plug is placed inside the oil pipe, and sand is poured above the plug in preparation for slurry emptying. Cement slurry is loaded into the slurry emptying cylinder. A tool string is connected by a steel wire; the tool string, from top to bottom, consists of a rope cap, a weight rod, a vibrator, and the slurry emptying cylinder. The tool string is lowered into the oil pipe. The slurry emptying device is lowered to the sand surface position. At this point, neither the impact shear pin nor the piston shear pin has been cut short. The vibrator strikes downwards, cutting the impact shear pin first. The impact rod and valve move upwards to open the port of the lower sleeve. The piston shear pin is then cut short. The piston connecting rod moves downwards under the weight of the weight rod, pushing the cement slurry from the port into the lower sleeve, and it flows out from the slurry outlet of the lower sleeve. The limiting spring moves to the limiting ring groove position, and the cement slurry is completely squeezed out by the piston. The tool string is removed from the oil pipe. Whether to continue slurry emptying is determined based on the height of the preset cement plug.

[0005] The existing technology uses a shocker to break the shear pins and open the ash bucket. While this avoids the problem of accuracy issues caused by lifting and lowering, it has drawbacks such as long preparation time and the time-consuming and labor-intensive process of reinstalling the shear pins.

[0006] Announcement No. CN106014331B discloses a cable injection suspension cement plug tool, comprising a glass plate, a side ash discharge joint, a rotating component, and an impact rod assembly arranged sequentially from the bottom ash discharge joint upwards. The rotating component includes a motor and a turntable rotatably connected to the motor. The impact rod assembly is positioned above the cement slurry and includes a fan-shaped expansion section, a fan-shaped key, and an impact head, all integrally formed. The fan-shaped expansion section is placed on the upper end face of a fan-shaped tray integrally formed with the ash discharge cylinder assembly. The fan-shaped key is placed in a radial keyway correspondingly provided on the turntable. The glass plate is clamped between the ash discharge cylinder assembly and the side ash discharge joint. When the cable is lowered to a predetermined depth, the ground is energized, causing the downhole motor to drive the turntable and impact rod to rotate, thereby releasing the impact rod to break the glass plate and open the ash discharge cylinder.

[0007] The existing technology opens the ash discharge cylinder by breaking the glass, but the accumulation of glass fragments on the ash discharge joint will create significant resistance to the cement slurry, affecting the discharge efficiency, and it is also possible to injure workers when the ash discharge cylinder is re-prepared.

[0008] Publication number CN112196490A discloses an electromechanical slurry dumping tool for oil and gas wells. During use, it is connected to a tool string, which, from top to bottom, consists of a cable, a bridle, a magnetic positioning device, and the electromechanical slurry dumping tool. First, the tool string is transported to the designed depth above the bridge plug via the cable. Then, power is supplied to the motor of the downhole electromechanical slurry dumping tool via the cable. The motor rotates, which in turn drives the lead screw to rotate via a coupling. Next, a weighted piston connected to the lead screw moves downwards under the constraint of a limiting pin, entering the slurry cylinder joint. The weighted piston squeezes the cement slurry inside the slurry cylinder, thus applying shear force to the piston. When the shear force reaches a certain level, the piston pin breaks, and the piston falls into the basket below the slurry cylinder. The cement slurry inside the slurry cylinder flows through the drain hole to the upper part of the bridge plug inside the wellbore under gravity, completing the slurry dumping process.

[0009] The existing technology releases the piston by applying pressure to break the shear pin and open the ash cylinder. Although this avoids the problem of accuracy being affected by lifting and lowering, it has the problems of long preparation time and time-consuming and laborious shear pin reinstallation.

[0010] In summary, the technical solutions, technical problems to be solved, and beneficial effects of the above-disclosed technologies are all different from those of this utility model. For more technical features, technical problems to be solved, and beneficial effects of this utility model, the above-disclosed technical documents do not provide any technical inspiration. Utility Model Content

[0011] To address the aforementioned deficiencies in existing technologies, the purpose of this utility model is to provide an electrically controlled precision cement plugging device for well workover operations. This device uses a bridle for insertion and a cable to transmit operating signals. The operation process does not affect the device depth, thus improving cement injection accuracy and enabling rapid preparation for secondary cement removal.

[0012] To achieve the above objectives, the present invention adopts the following technical solution:

[0013] A precision cement plugging device with electronic control for well workover operations includes a valve body, an upper connecting part, a lower connecting part, and an equipment placement part. The outer wall of the equipment placement part has an equipment groove, and the inner wall of the equipment placement part has a slide rail communicating with the equipment groove. A driving device is disposed in the equipment groove, and a valve plate is disposed in the slide rail. The valve plate is connected to the output shaft of the driving device via a transmission mechanism. The driving device causes the valve plate to slide along the slide rail. A plug core is disposed above the valve plate inside the equipment placement part.

[0014] Furthermore, the valve body is provided with an upper connecting part, a lower connecting part, and an equipment placement part from top to bottom.

[0015] Furthermore, the outer diameter of the lower connecting part is smaller than the outer diameter of the upper connecting part; the outer wall of the lower connecting part is connected to the recovery cylinder;

[0016] Specifically, the outer diameter of the device placement part is smaller than the outer diameter of the lower connecting part;

[0017] Specifically, the upper end of the recycling cylinder is a connector, and the portion of the recycling cylinder below the valve body is provided with an outlet hole. The inner diameter of the recycling cylinder connector is equal to the outer diameter of the equipment placement part.

[0018] Furthermore, the driving device is a motor;

[0019] Specifically, the transmission mechanism includes a worm gear and a worm wheel, and the valve plate includes a limiting slider and a lead screw;

[0020] Specifically, the output shaft of the motor is connected to the worm, the limiting slider is located in the slide rail and is sealed to the slide rail, the lead screw is located in the equipment slot, the worm wheel has internal threads and is screwed onto the lead screw, and the worm wheel meshes with the worm.

[0021] Specifically, the movement of the lead screw is restricted by the inner wall of the recovery cylinder, preventing the limiting slider from completely disengaging from the slide rail.

[0022] Furthermore, the equipment slot, slide, drive device, and valve plate constitute a limiting unit, and at least two limiting units are provided, evenly distributed along the circumference of the valve body.

[0023] Furthermore, the valve body is provided with an inner wire passage hole for the motor lead wire to pass through, and the inner wire passage hole is sealed with resin.

[0024] Specifically, the motor leads are fed into an inner cable, and a cable connector is provided above the inner cable.

[0025] Furthermore, a sealing ring is provided between the recycling cylinder and the equipment placement part above and below the equipment trough, and a sealing ring is provided between the valve plate and the slide.

[0026] Furthermore, a quick-connect assembly is connected to the upper end of the valve body, the quick-connect assembly including a connecting pipe, a movable short section, and a movable nut;

[0027] Specifically, the lower end of the connecting pipe is connected to the upper end of the valve body, a first limiting ring is provided on the outer wall of the upper end of the movable section, a second limiting ring is provided on the inner wall of the lower end of the movable nut, the movable nut is inserted from below the movable section, and the outer wall of the lower end of the movable section is connected to the inner wall of the upper end of the valve body by welding.

[0028] Furthermore, the upper end of the movable nut is connected to a mortar pipe column.

[0029] Furthermore, the movable section is provided with an inner retaining ring, the inner retaining ring is provided with a cable retaining hole, and the inner cable is retained in the cable retaining hole.

[0030] Compared with the prior art, the present invention has the following advantages:

[0031] 1. This utility model solves the shortcomings of existing cement injection technology, reduces the labor intensity of operators, eliminates the need for backwashing well operations, reduces oil layer pollution, avoids the generation of cement slag, and can achieve both solid plug and suspended plug injection. It has a large single slurry capacity and can complete 30m of cement injection construction in one go. Compared with conventional cement plug injection operations, this device does not require the insertion of tubing. It only requires a rapid sand retrieval machine in conjunction with the cement injection tools to complete the operation, significantly shortening the construction time per well.

[0032] 2. The electric control operation of this utility model is simple and improves the operation efficiency by more than 8 times compared with conventional tubing tripping and ash injection operations. Compared with the wire rope rapid well repair technology, it has higher precision and is more convenient and efficient to operate.

[0033] 3. When performing secondary ash pouring, this utility model only requires extending the valve plate, inserting the plug core, and quickly connecting the slurry pipe column, which is convenient and fast, and improves the efficiency of continuous ash pouring. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the structure of an electrically controlled precision cement plugging device for well repair operations according to this utility model;

[0035] Figure 2This is a schematic diagram of the valve body in this utility model;

[0036] Figure 3 This is a schematic diagram of the valve plate in this utility model.

[0037] In the diagram: 1. Mortar pipe column; 2. Upper cable; 3. Upper retaining ring; 4. Movable nut; 5. Cable connector; 6. Movable short section; 7. Connecting pipe; 8. Valve body; 8.1. Upper connecting part; 8.2. Tapered end; 8.3. Inner cable passage hole; 8.4. Slide rail; 8.5. Equipment trough; 8.6. Lower connecting part; 9. Plug; 10. Valve plate; 10.1. Limiting slider; 10.2. Lead screw; 11. Worm gear; 12. Recovery cylinder; 13. Outlet hole; 14. Motor; 15. Worm; 16. Inner cable; 17. Inner retaining ring. Detailed Implementation

[0038] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0039] Example 1:

[0040] Please see Figures 1 to 2 The present invention provides an electrically controlled precision cement plugging device for well repair operations, comprising a valve body 8, wherein the valve body 8 comprises, from top to bottom, an upper connecting part 8.1, a lower connecting part 8.6, and an equipment placement part. The valve body 8 has a tapered opening 8.2 above the equipment placement part, making the inner diameter of the valve body 8 larger at the top and smaller at the bottom.

[0041] The upper connecting part 8.1 is provided with external or internal threads for connecting to the upper pipe column or equipment.

[0042] The outer diameter of the lower connecting part 8.6 is smaller than the outer diameter of the upper connecting part 8.1. The lower connecting part is provided with an external thread. The outer wall of the lower connecting part 8.6 is connected to the recovery cylinder 12 by the thread. The step between the lower connecting part 8.6 and the upper connecting part 8.1 can play a positioning role. The part of the recovery cylinder 12 below the valve body 8 is provided with an outlet hole 13 for cement to flow out.

[0043] The outer diameter of the device placement part is smaller than the outer diameter of the lower connecting part 8.6. The outer wall of the device placement part is provided with a device groove 8.5, and the inner wall of the device placement part is provided with a slide 8.4 that communicates with the device groove 8.5.

[0044] A precision cement plugging device controlled by an electric control for well workover operations also includes an electric limit device and a plug core 9. The electric limit device includes a valve plate 10, a transmission mechanism, and a motor 14. The valve plate 10 is slidably disposed in a slide rail 8.4, and the motor 14 is fixedly disposed in an equipment slot 5. The output shaft of the valve plate 10 and the motor 14 are connected through the transmission mechanism, and the motor 14 enables the valve plate 10 to slide along the slide rail 8.4. The plug core 9 is disposed in the valve body and is located between the conical constriction 8.2 and the slide rail 8.4. The plug core 9 sits on the extended valve plate 10. When the motor 14 retracts the valve plate 10, the plug core 9 falls into the recovery cylinder 12.

[0045] Specifically, the valve body 8 is provided with an inner wire passage hole 8.3 for the lead wire of the motor 14 to pass through, and the inner wire passage hole is sealed with resin.

[0046] Specifically, the equipment slot 8.5, slide rail 8.4, and electric limit device constitute a limit unit, and at least two limit units are provided, evenly distributed along the circumference of the valve body 8.

[0047] Specifically, the lead wire of the motor 4 is fed into the inner cable 16, and a cable connector 5 is provided above the inner cable 16. The inner cable 16 is a high-temperature and high-pressure resistant cable, and the cable connector 5 is an easy-to-plug connector.

[0048] Specifically, the upper end of the recycling cylinder 12 is a connector, and the inner diameter of the connector of the recycling cylinder 12 is equal to the outer diameter of the equipment placement part, so that the recycling cylinder 12 can protect the electric limit device.

[0049] Specifically, a sealing ring is provided between the recycling cylinder 12 and the equipment placement part above and below the equipment tank 8.5, and a sealing ring is provided between the valve plate 10 and the slide 8.4 to prevent water from entering the equipment tank 8.5.

[0050] Example 2:

[0051] Based on Example 1, combined with Figure 3 This embodiment proposes further improvements to an electrically controlled precision cement plugging device for well workover operations.

[0052] In this embodiment, the upper end of the valve body 8 is connected to a quick-connect assembly, which includes a connecting pipe 7, a movable short section 6, and a movable nut 4. The lower end of the connecting pipe 7 is threadedly connected to the upper end of the valve body 8. The upper outer wall of the movable short section 6 is provided with a first limiting ring, and the lower inner wall of the movable nut 4 is provided with a second limiting ring. The movable nut 4 is inserted from below the movable short section 6, and the lower outer wall of the movable short section 6 is connected to the upper inner wall of the valve body 8 by welding.

[0053] Specifically, the movable section 6 is provided with an inner retaining ring 17, which has a cable retaining hole. The inner cable 6 is held in the cable retaining hole, which stabilizes the position of the cable joint 5. This not only assists in quick installation but also keeps the inner cable 6 stable during the well descent, thus protecting the cable joint 5.

[0054] The upper end of the movable nut 4 is connected to the pipe column or other equipment. When connecting, the cable 2 and the cable connector 5 must be connected first. The movable nut 4 is then slid down onto the upper end face of the connecting pipe 7 to make room for installation. After installation, the movable nut is connected to the upper pipe column or equipment. The quick-installation component reduces the installation difficulty and speeds up the installation process.

[0055] In this embodiment, the transmission mechanism includes a worm gear 15 and a worm wheel 11. The valve plate 10 includes a limiting slider 10.1 and a lead screw 10.2. The output shaft of the motor 14 is connected to the worm gear 15. The limiting slider 10.1 is located in the slide rail 8.4 and is sealed to the slide rail 8.4. The lead screw 10.2 is located in the equipment groove 8.5. The worm wheel 11 has internal threads and is screwed onto the lead screw 10.2. The worm wheel 11 meshes with the worm gear 15.

[0056] Motor 14 drives worm 15 to rotate, worm 15 drives worm wheel 11 to rotate, limit slider 10.1 cannot rotate under the restriction of slide rail 8.4, lead screw 10.2 cannot rotate, converting rotation into linear motion, so that limit slider 10.1 slides in slide rail 8.4.

[0057] The movement of the lead screw 10.2 is restricted by the inner wall of the recovery cylinder 12, preventing the limit slider 10.1 from completely disengaging from the slide rail 8.4 and maintaining a seal.

[0058] Example 3:

[0059] Based on Example 2, this example provides a method for using an electrically controlled precision cement plug injection device for well workover operations, specifically including the following steps:

[0060] S1. When starting the grout injection operation, connect the upper cable 2 of the grout pipe column 1 to the cable connector 5, then lift the movable nut 4 and rotate the movable nut 4 to connect the lower end external thread of the grout pipe column 1. Then inject grout into the grout pipe column. The upper part of the grout pipe column 1 is connected to the bridle and cable.

[0061] S2. The slurry tubing is transported to the designated depth in the well using the cable of the sand-removing machine. A power signal is sent to the motor 14 in the valve body 8 from the ground. After a 1-minute delay, the power is automatically cut off. At this time, the limit slider 10.1 opens, the valve plate 10 returns to the recovery cylinder 12, and then the slurry tubing is lifted. At this time, the valve plate 10 has been retracted into the slide. The plug core 9 falls into the recovery cylinder 12 under its own weight and the pressure of the slurry above. The slurry flows out from the outflow holes 13 around the recovery cylinder 12 and then solidifies in the wellbore to form a local seal, achieving the effect of precise slurry injection.

[0062] S3. When lifting the grout pipe column 1 to the ground, the movable nut 4 and cable connector 5 need to be removed in sequence, and the recovery cylinder 12 needs to be removed. Check and clean each threaded connection and valve plate 10, and apply lubricating grease to the worm gear 11, worm 15 and lead screw 10.2. When a new grout pipe column needs to be connected, extend the valve plate 10, insert the plug 9, and repeat step S1.

[0063] The mortar pipe column 1 has an upper retaining ring 3 at its lower end. The upper retaining ring 3 has the same structure as the inner retaining ring 17. The upper retaining ring 3 is used to fix and stabilize the upper cable 2.

[0064] It should be noted that the grout tubing 1 is used to hold cement grout, and the bridle is a downhole cable connection device. Those skilled in the art are clear about their structure, so it will not be discussed in detail here.

[0065] All components not discussed in detail in this application, as well as the connection methods of these components, are well-known technologies in this field. They can be directly applied and will not be elaborated further.

[0066] In this utility model, the term "multiple" refers to two or more unless otherwise explicitly defined. The terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; "linking" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0067] In the description of this utility model, it should be understood that the terms "upper", "lower", "left", "right", "front", "rear", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or unit referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0068] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0069] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A precision cement plugging device with electronic control for well workover operations, comprising a valve body, characterized in that, The valve body is provided with a device placement section; The outer wall of the equipment placement part is provided with an equipment groove, and the inner wall of the equipment placement part is provided with a slide rail communicating with the equipment groove. A driving device is provided in the equipment groove, and a valve plate is provided in the slide rail. The valve plate is connected to the output shaft of the driving device through a transmission mechanism. The drive device causes the valve plate to slide along the slide rail; The device placement section has a plug located above the valve plate.

2. The electrically controlled precision cement plugging device for well workover operations according to claim 1, characterized in that, The valve body is provided with an upper connecting part, a lower connecting part, and an equipment placement part from top to bottom.

3. The electrically controlled precision cement plugging device for well workover operations according to claim 2, characterized in that, The outer diameter of the lower connecting part is smaller than the outer diameter of the upper connecting part; the outer wall of the lower connecting part is connected to the recovery cylinder; The outer diameter of the device placement part is smaller than the outer diameter of the lower connecting part; The upper end of the recycling cylinder is a connector, and the part of the recycling cylinder below the valve body is provided with an outlet hole. The inner diameter of the recycling cylinder connector is equal to the outer diameter of the equipment placement part.

4. The electrically controlled precision cement plugging device for well workover operations according to claim 3, characterized in that, The driving device is a motor; The transmission mechanism includes a worm gear and a worm wheel, and the valve plate includes a limiting slider and a lead screw. The output shaft of the motor is connected to the worm gear, the limiting slider is located in the slide rail and is sealed to the slide rail, the lead screw is located in the equipment slot, the worm wheel has internal threads and is screwed onto the lead screw, and the worm wheel meshes with the worm gear; The movement of the lead screw is restricted by the inner wall of the recovery cylinder, preventing the limiting slider from completely disengaging from the slide rail.

5. The electrically controlled precision cement plugging device for well workover operations according to claim 1, characterized in that, The equipment slot, slide, drive device, and valve plate constitute a limiting unit. At least two limiting units are provided and are evenly distributed along the circumference of the valve body.

6. The electrically controlled precision cement plugging device for well workover operations according to claim 4, characterized in that, The valve body is provided with an inner wire passage hole for the motor lead wire to pass through, and the inner wire passage hole is sealed with resin. The motor leads converge into the inner cable, and a cable connector is provided above the inner cable.

7. The electrically controlled precision cement plugging device for well workover operations according to claim 3, characterized in that, A sealing ring is provided between the recycling cylinder and the equipment placement part, both above and below the equipment trough, and a sealing ring is provided between the valve plate and the slide.

8. A precision cement plugging device with electronic control for well workover operations according to claim 6, characterized in that, The upper end of the valve body is connected to a quick-connect assembly, which includes a connecting pipe, a movable short section, and a movable nut. The lower end of the connecting pipe is connected to the upper end of the valve body. A first limiting ring is provided on the outer wall of the upper end of the movable section, and a second limiting ring is provided on the inner wall of the lower end of the movable nut. The movable nut is inserted from below the movable section, and the outer wall of the lower end of the movable section is connected to the inner wall of the upper end of the valve body by welding.

9. A precision cement plugging device with electronic control for well workover operations according to claim 8, characterized in that, The upper end of the movable nut is connected to the mortar pipe column.

10. A precision cement plugging device with electronic control for well workover operations according to claim 8, characterized in that, The movable section is provided with an inner retaining ring, and the inner retaining ring is provided with a cable retaining hole, in which the inner cable is retained.

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