Novel slip type underground throttler

Abstract

The utility model relates to the technical field of natural gas extraction equipment, and particularly discloses a novel slip type underground throttler which comprises a mandrel, a central pipe, a fishing mechanism, a slip, a cone, a transition sleeve and a rubber sleeve. The central pipe is connected with the mandrel in a sleeved mode and connected with the slip, the cone and the rubber barrel in a sliding mode, the central pipe is connected with a limiting step and a locking mechanism, the limiting step is connected with the slip, the mandrel is connected with a nut, a connecting mechanism and an air nozzle, the transition sleeve is connected with a baffle ring and a standby cap, and the locking mechanism is connected with the locking mechanism. The back-up cap is connected with the nut, the baffle ring abuts against the rubber sleeve, the fishing mechanism is connected with the mandrel, and the problem that in the prior art, a conventional slip type flow controller is slightly blocked in the throwing process, and mistaken setting is likely to be generated is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of natural gas mining equipment, in particular to a novel slip-type downhole throttle. Background Art

[0002] In natural gas production, downhole chokes are often installed in the gas wells for pressure reduction, throttling and production restriction. Downhole chokes are divided into slip chokes and fixed chokes according to different anchoring mechanisms. When the fixed choke is lowered into the oil pipe, it is necessary to connect the landing short circuit that matches the choke, resulting in less use on the production site. The slip choke has a full bore in the wellbore and a flexible sealing position, so it is widely used in gas fields. For the slip downhole choke, when the production needs to adjust the gas well production and replace the choke nozzle or when the choke fails, the choke needs to be salvaged. However, it is very inconvenient to salvage the choke and accidents are prone to occur.

[0003] Through the promotion and application of a large area, it is shown that the conventional slip-type choke is prone to mis-seating when encountering slight resistance during the deployment process. The choke will be seated in advance before reaching the designed sealing position. In addition, the axial distance of the rubber tube of the conventional slip-type choke will not increase during the salvage, so the sealing rubber tube cannot retract, resulting in large friction resistance during salvage and great difficulty in salvage. Once the choke fails to be salvaged, it will be blocked in the middle of the oil pipe, making it impossible to implement subsequent drainage and gas production measures to further improve the recovery rate, and ultimately the remaining production capacity of the gas well cannot be utilized. Utility Model Content

[0004] In order to solve the technical problem that the conventional slip-type choke may be easily mis-seated when encountering slight resistance during the placement process, the utility model provides a novel slip-type downhole choke.

[0005] The technical solution adopted by the utility model to solve its technical problems is:

[0006] A novel slip-type downhole throttle comprises a core shaft, a center tube, a salvage mechanism, a slip, a cone, a transition sleeve and a rubber tube; the center tube is sleeved on the core shaft and slidably connects the slip, the cone and the rubber tube, the center tube is connected with a limit step and a locking mechanism, the limit step is connected to the slip, the core shaft is connected with a nut, a connecting mechanism and a gas nozzle, the transition sleeve is connected with a retaining ring and a spare cap, the spare cap is connected to the nut, the retaining ring abuts the rubber tube, and the salvage mechanism is connected to the core shaft.

[0007] Furthermore, the salvage mechanism includes a salvage head, an end cover, a slip seat, an unsealing shear pin and a retaining ring. The salvage head is sleeved with the core shaft, the end cover is sleeved with the salvage head, the slip seat is fixedly connected to the end cover and the unsealing shear pin and abuts against the slip, and the retaining ring is fixedly connected to the salvage head and connected to the unsealing shear pin.

[0008] Furthermore, the connecting mechanism includes a connecting head, a delivery pin and a delivery head, the delivery pin is fixedly connected to the connecting head and the delivery head, and the connecting head is fixedly connected to the core shaft.

[0009] Furthermore, the locking mechanism includes a locking ring and a locking ring sleeve, the locking ring is connected to the central pipe and abuts against the locking ring sleeve, and the locking ring sleeve is slidably connected to the transition sleeve.

[0010] Furthermore, the air nozzle is slidably connected to the core shaft, the core shaft is threadedly connected with a connecting sleeve, and the connecting sleeve abuts against the air nozzle.

[0011] Furthermore, a sand-proof net is connected inside the connecting sleeve.

[0012] Furthermore, the connecting sleeve is threadedly connected with a pressure cap, and the pressure cap abuts against the sand control net.

[0013] Furthermore, the core shaft is sleeved with a locking plate, and the locking plate abuts against the nut and the connecting sleeve.

[0014] Beneficial effects of the utility model:

[0015] 1. The utility model adopts a limiting step to limit the slips entering the oil pipe, so as to prevent the slips from being expanded by the cone during the throttle delivery process, so that the outer diameter of the slips is always smaller than the inner diameter of the oil pipe, and prevents the slips from being mistakenly seated when encountering slight resistance before reaching the oil pipe sealing position, thus solving the problem that the conventional slip-type throttle is prone to mistakenly seated when encountering slight resistance during the delivery process;

[0016] 2. The utility model adopts a fishing head, unsealing shear pins, retaining rings, end covers and slip seats to allow the slips of the throttle to retract and the rubber tube to expand along the axial direction of the core shaft during fishing, so that the rubber tube and the slips are away from the oil pipe, which improves the convenience of fishing the throttle from the oil pipe;

[0017] 3. The utility model adopts a locking mechanism to lock the center tube, thereby preventing the rubber sleeve from expanding axially along the core shaft after abutting the inner wall of the oil pipe, ensuring the sealing effect between the rubber sleeve and the oil pipe. The locking ring sleeve can ensure that the working state of the locking ring is more stable and reliable, and prevent the locking ring from losing its locking effect under the action of external load. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of a novel slip-type downhole choke in the utility model;

[0019] Figure 2 for Figure 1 A schematic diagram of the structure of the central tube, the locking ring and the locking ring sleeve;

[0020] Figure 3 for Figure 2Structural schematic diagram of the center tube and the limiting step;

[0021] Figure 4 for Figure 2 Schematic diagram of the structure of the middle locking ring;

[0022] Figure 5 for Figure 4 A side cross-sectional view of the middle lock ring;

[0023] Among them, 1-launching head, 2-launching pin, 3-connecting head, 4-core shaft, 5-fishing head, 6-end cover, 7-slip seat, 8-unsealing shear nail, 9-retaining ring, 10-slip, 11-center tube, 12-cone, 13-rubber cylinder, 14-retaining ring, 15-locking ring sleeve, 16-locking ring, 17-transition sleeve, 18-spare cap, 19-nut, 20-locking plate, 21-air nozzle, 22-connecting sleeve, 23-sand prevention net, 24-pressure cap, 25-limiting step. DETAILED DESCRIPTION

[0024] In order to deepen the understanding of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. The embodiments are only used to explain the present invention and do not limit the protection scope of the present invention.

[0025] Example:

[0026] The specific implementation process of the utility model: a new type of slip-type downhole throttle, such as Figure 1-Figure 3 As shown, it includes a core shaft 4, a center tube 11, a salvaging mechanism, a slip 10, a cone 12, a transition sleeve 17 and a rubber tube 13; the center tube 11 is sleeved on the core shaft 4, and is slidably connected to the slip 10, the cone 12 and the rubber tube 13, the center tube 11 is connected to a limiting step 25 and a locking mechanism, the limiting step 25 is connected to the slip 10, the core shaft 4 is connected to a nut 19, a connecting mechanism and a gas nozzle 21, the transition sleeve 17 is connected to a retaining ring 14 and a spare cap 18, the spare cap 18 is connected to the nut 19, the retaining ring 14 abuts against the rubber tube 13, and the salvaging mechanism is connected to the core shaft 4.

[0027] After the new type of slip-type downhole choke of the utility model is lowered to the predetermined position in the oil pipe, the steel wire tool string is struck downward, the steel wire tool string is threadedly connected to the connecting mechanism, the salvage mechanism, slip 10, and the center pipe 11 will all move downward relative to other components of the choke, the slip 10 is squeezed by the cone 12 and radially extends out to be initially anchored with the oil pipe, and then the steel wire tool string is repeatedly pulled up, the core shaft 4, the cone 12, the rubber cylinder 13, the retaining ring 14, the locking mechanism, the transition sleeve 17, the spare cap 18, the nut 19, and the air nozzle 21 will all move upward relative to other components of the choke, and in this process the rubber cylinder 13 Axial compression and radial expansion are achieved, and the oil pipe is abutted. The slip 10 is squeezed by the cone 12 and further anchored to the oil pipe, and the locking mechanism will also move upward relative to the center pipe 11 and lock with it, so that the rubber sleeve 13 will not retract axially and achieve sealing with the oil pipe. The center pipe 11 is fixedly connected to the limit step 25 and is threadedly connected to the nut 19. A step groove is provided on the slip 10, and the limit step 25 is inserted into the step groove, thereby forming a connection between the limit step 25 and the slip 10. The transition sleeve 17 is threadedly connected to the retaining ring 14 and the spare cap 18, and the spare cap 18 is threadedly connected to the nut 19.

[0028] like Figure 1 As shown, the salvage mechanism includes a salvage head 5, an end cover 6, a slip seat 7, an unsealing shear pin 8 and a retaining ring 9. The salvage head 5 is sleeved on the core shaft 4, the end cover 6 is sleeved on the salvage head 5, the slip seat 7 is fixedly connected to the end cover 6 and the unsealing shear pin 8, and abuts against the slip 10, and the retaining ring 9 is fixedly connected to the salvage head 5 and connected to the unsealing shear pin 8.

[0029] When it is necessary to salvage the new type of slip 10 downhole throttle of the utility model, the salvage tool is lowered into the well, the salvage tool grasps the neck of the salvage head 5 and then lifts the salvage tool, and the salvage head 5 moves up relative to the other parts of the throttle. Due to the large friction between the rubber cylinder 13 and the oil pipe, as the salvage head 5 moves up, the retaining ring 9 will be driven to move up, causing the unsealing shear nail 8 to be cut, and the salvage head 5 continues to move up. The center pipe 11 opens and loses the support of the salvage head 5 and becomes a contracted state. The salvage head 5 will drive the end cover 6, the slip seat 7, and the slip 10 to move up. The slip 10 is away from the inner wall of the oil pipe and retracts to achieve unblocking. At the same time, the radially expanded rubber cylinder 13 will retract, so that the rubber cylinder 13 is away from the inner wall of the oil pipe and unblocking is achieved. The throttle is successfully salvaged, and the fixed connection between the slip seat 7 and the end cover 6 can be a threaded connection. A shear nail groove is provided on the retaining ring 9, and the unsealing shear nail 8 is plugged into the shear nail groove, thereby forming a connection between the unsealing shear nail 8 and the retaining ring 9.

[0030] like Figure 1 As shown, the connection mechanism includes a connection head 3 , a delivery pin 2 and a delivery head 1 , the delivery pin 2 is fixedly connected to the connection head 3 and the delivery head 1 , and the connection head 3 is fixedly connected to the core shaft 4 .

[0031] After the rubber sleeve 13 is sealed with the oil pipe, the wire tool string can be hit to cut off the release pin 2 of the release head 1 and the connecting head 3, so that the throttle is successfully sealed. At this time, the wire tool string is lifted up to allow the wire tool string together with the release head 1 to exit the oil pipe and the wellbore, and the well can be opened to realize the downhole throttling function. The wire tool string is threadedly connected to the release head 1, and the fixed connection between the connecting head 3 and the core shaft 4 can be a threaded connection. The connecting head 3 can be located in the salvage head 5 and is in a built-in state. The purpose is that after the throttle is sealed, the connecting head 3 is in a built-in state to ensure that the salvage tool can reliably enter the fish during salvage.

[0032] like Figure 1 , Figure 2 , Figure 4 as well as Figure 5 As shown, the locking mechanism includes a locking ring 16 and a locking ring sleeve 15 , the locking ring 16 is connected to the central pipe 11 and abuts against the locking ring sleeve 15 , and the locking ring sleeve 15 is slidably connected to the transition sleeve 17 .

[0033] The ends of the locking ring 16 and the center tube 11 can both be serrated and engage with each other, thereby forming a connection between the locking ring 16 and the center tube 11, and can also facilitate the installation and compensation of deformation of the locking ring 16. After the slip 10 is anchored to the oil pipe, the locking ring 16 also moves upward relative to the center tube 11 and locks with it, so that the rubber sleeve 13 will not retract axially and achieve sealing with the oil pipe.

[0034] like Figure 1 As shown, the air nozzle 21 is slidably connected to the core shaft 4 , and the core shaft 4 is threadedly connected with a connecting sleeve 22 , and the connecting sleeve 22 abuts against the air nozzle 21 .

[0035] The gas nozzle 21 can throttle the natural gas entering the core shaft 4 in the oil pipe, and the connecting sleeve 22 abuts against the gas nozzle 21, which can facilitate the disassembly and installation of the gas nozzle 21.

[0036] like Figure 1 As shown, a sand prevention net 23 is connected inside the connecting sleeve 22 .

[0037] The sand prevention net 23 can filter the natural gas entering the core shaft 4 from the oil pipe, thereby reducing the blockage of the core shaft 4 by debris.

[0038] like Figure 1 As shown, the connecting sleeve 22 is threadedly connected with a pressing cap 24 , and the pressing cap 24 abuts against the sand control net 23 .

[0039] The sand control net 23 can be slidably connected to the connecting sleeve 22 , and the pressing cap 24 abuts against the sand control net 23 and is threadedly connected to the connecting sleeve 22 , which can facilitate the disassembly and installation of the sand control net 23 .

[0040] like Figure 1As shown, the core shaft 4 is sleeved with a locking piece 20 , and the locking piece 20 abuts against the nut 19 and the connecting sleeve 22 .

[0041] The locking piece 20 abuts against the nut 19 and the connecting sleeve 22 to maintain the stability of the relative position between the nut 19 and the connecting sleeve 22. The natural gas in the oil pipe can first enter the connecting sleeve 22, then enter the core shaft 4 through the sand-proof net 23 and the gas nozzle 21, and then leave through the connector 3 and the salvage head 5.

[0042] The above embodiments should not limit the present invention in any way, and any technical solutions obtained by equivalent replacement or equivalent conversion shall fall within the protection scope of the present invention.

Claims

1. A new type of slip-type downhole choke, characterized by: It includes a mandrel, a center tube, a fishing mechanism, a slip, a cone, a transition sleeve and a rubber cylinder; The center tube is sleeved on the core shaft and is slidably connected to the cava, the cone and the rubber cylinder. The center tube is connected to a limiting step and a locking mechanism. The limiting step is connected to the cava. The core shaft is connected to a nut, a connecting mechanism and a gas nozzle. The transition sleeve is connected to a retaining ring and a spare cap. The spare cap is connected to the nut. The retaining ring abuts the rubber cylinder. The salvaging mechanism is connected to the core shaft.

2. A novel slip-type downhole choke according to claim 1, characterized in that: The salvaging mechanism comprises a salvaging head, an end cover, a slip seat, an unsealing shear pin and a retaining ring. The salvaging head is sleeved with the mandrel, the end cover is sleeved with the salvaging head, the slip seat is fixedly connected with the end cover and the unsealing shear pin and abuts against the slip, and the retaining ring is fixedly connected with the salvaging head and connected with the unsealing shear pin.

3. A novel slip-type downhole choke according to claim 2, characterized in that: The connecting mechanism comprises a connecting head, a delivery pin and a delivery head, the delivery pin is fixedly connected to the connecting head and the delivery head, and the connecting head is fixedly connected to the core shaft.

4. A novel slip-type downhole choke according to claim 1, characterized in that: The locking mechanism comprises a locking ring and a locking ring sleeve, wherein the locking ring is connected to the central pipe and abuts against the locking ring sleeve, and the locking ring sleeve is slidably connected to the transition sleeve.

5. A novel slip-type downhole choke according to claim 1, characterized in that: The air nozzle is slidably connected to the core shaft, the core shaft is threadedly connected with a connecting sleeve, and the connecting sleeve abuts against the air nozzle.

6. A novel slip-type downhole choke according to claim 5, characterized in that: A sand prevention net is connected inside the connecting sleeve.

7. A novel slip-type downhole choke according to claim 6, characterized in that: The connecting sleeve is threadedly connected with a pressure cap, and the pressure cap abuts against the sand control net.

8. A novel slip-type downhole choke according to claim 5, characterized in that: The core shaft is sleeved with a locking plate, and the locking plate abuts against the nut and the connecting sleeve.

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