Two-stage overshot type well dropping screw pump rotor fishing tool

Abstract

The utility model discloses two -level slip -type well falling screw rod pump rotor fishing tool, including upper joint, first self -adaptation type slip module A, second hinge type slip module B and leading shoe, first self -adaptation type slip module A includes conical slip cylinder, slip steel ring, restraint block, conical slip, multiple conical slips are evenly hung in slip steel ring, and are evenly separated by slip steel ring step, second hinge type slip module B includes hinge slip cylinder, torsion spring, circular ring, hinge slip, the middle part of hinge slip cylinder is equipped with multiple evenly distributed window groove, boss and hinge through -hole, and hinge slip one end is equipped with second arc face sawtooth slip tooth, and the other end is equipped with cutting groove, circular ring hole, and the lower end of leading shoe is equipped with vertical guide surface and helical guide surface. The utility model discloses through different types' first self -adaptation type slip module A, second hinge type slip module B and leading shoe, can all -round slip smooth screw rod pump rotor in many aspects, realizes once successful fishing.

Description

Technical Field

[0001] This utility model belongs to the technical field of oilfield petroleum extraction equipment, and relates to a two-stage slip-type screw pump rotor retrieval tool. Background Technology

[0002] With advancements in oil and gas well engineering technology, screw pump production technology is commonly used for oil wells with high fluid production. Screw pumps, consisting mainly of a motor, protector, and screw pump rotor assembled in series with screws, are lowered into the well to below the fluid level to pump fluid to the surface. However, as screw pumps operate in the harsh environment of corrosion and vibration within the well for extended periods, the screws connecting the motor, protector, and screw pump are prone to loosening, causing the screw pump rotor and lower components to fall into the well, resulting in downhole accidents. Currently, there are no dedicated tools in China for retrieving screw pump rotors to address these rotor fall-in-well accidents. Conventional retrieval tools have low success rates, long well occupation periods, and even the risk of well abandonment.

[0003] The utility model patent "Screw Drill Rotor Retrieval Tool" (Publication No.: CN201297148Y, Publication Date: 2009-08-26) discloses a retrieval structure component including a cylinder, a retrieval thread, and a conical body. The upper male thread of the cylinder is used to connect to the female thread of the oil pipe, and the lower end of the cylinder is connected to the upper end of the conical body. A limiting key is provided on the end face of the cylinder, and the limiting key is located in the inner cavity of the conical body. An outer conical surface is provided on the outer surface of the retrieval thread, and a keyway that cooperates with the limiting key is provided on one end face of the retrieval thread. Multiple evenly distributed slots are provided along the longitudinal direction of the retrieval thread, and each slot has an open end and a bottom end. The retrieval thread is located in the inner cavity of the conical body, and the limiting key and the keyway cooperate with each other. The outer conical surface of the retrieval thread and the inner surface of the conical body cooperate and can move along the axial direction of the conical body. This patent mainly relies on lowering the retrieval tool, allowing the screw drill rotor to enter the retrieval cylinder, and then pushing the retrieval threads upwards within the conical body to move axially upwards. This causes the retrieval threads to expand radially and constrain the screw drill rotor. The retrieval tool is then lifted to achieve retrieval. However, this retrieval structure uses only a single-stage retrieval structure, and the surface of the screw drill rotor is smooth. During the lifting process of the retrieval tool, the retrieval structure is not easy to lock the screw drill rotor, making it difficult to overcome the weight of the object falling from the screw drill and other resistances. This results in a low retrieval success rate and makes it unsuitable for retrieval of screw pump rotors.

[0004] The utility model patent "A Screw Motor Rotor Milling and Fishing Tool" (Publication No.: CN222478688U, Publication Date: 2025-02-14) mainly comprises an upper connector, a cylinder assembly, an auxiliary milling assembly, and a guide shoe assembly connected in sequence. The cylinder assembly contains a spiral clamp and a control ring. The guide shoe assembly includes a milling assembly, a guide shoe, and a guide hook connected in sequence. This tool, through the design of the guide hook and extended guide shoe, as well as a double milling mechanism, primarily relies on the guide hook and guide shoe to guide the screw motor rotor into the guide shoe and guide the fish. During fishing, the fish is secured by pressing down on the spiral clamp and control ring inside the cylinder assembly, achieving the simultaneous insertion and head trimming of the fish, thus improving drilling efficiency and safety. However, this patent uses a downward pressing method, mainly relying on the first-stage spiral slip inside the cylinder assembly to hold the fallen fish in place. The success rate of lifting the screw pump rotor using a special retrieval tool to overcome the weight of the fallen fish and other resistances to achieve a smooth surface for the screw pump rotor is low. Although the broken alloy blocks on the auxiliary milling ring of the auxiliary milling assembly can be used to mill and trim the fish head, they are not necessary for the high-strength screw pump rotor and do not achieve the desired milling effect.

[0005] In view of the shortcomings of the existing technology, there is an urgent need for a special salvage tool that can be used to salvage screw pump rotors in wells. Utility Model Content

[0006] The purpose of this invention is to provide a two-stage slip-type screw pump rotor retrieval tool, which solves the problem of the inability to retrieve screw pump rotors after they have been dropped into the well in the existing technology.

[0007] The technical solution adopted in this utility model is a two-stage slip-type well-dumping screw pump rotor salvage tool, including an upper connector, a first-stage adaptive slip module A connected to the upper connector, a second-stage hinge slip module B connected to the first-stage adaptive slip module A, and a guide shoe connected to the second-stage hinge slip module B.

[0008] The features of this utility model also include:

[0009] The first-level adaptive slip module A includes a conical slip cylinder with a slip steel ring inside. Multiple conical slips are evenly arranged on the slip steel ring, and the outer wall of each conical slip is tightly attached to the inner wall of the conical slip cylinder. The inner diameter of the lower end of the upper connector is smaller than the inner diameter of the slip steel ring. Each conical slip has a constraint cavity, and a constraint block is installed in each constraint cavity. The upper end of the conical slip cylinder is threaded to the lower end of the upper connector, and the inner diameter of the lower end of the upper connector is smaller than the inner diameter of the slip steel ring. The lower end of the conical slip cylinder is threaded to the upper end of the second-level hinged slip module B.

[0010] The slip ring includes a steel ring with multiple dividing protrusions evenly arranged on it. The number of dividing protrusions corresponds to the number of conical slips, and the multiple conical slips are evenly separated by the dividing protrusions.

[0011] The dividing boss consists of an upper dividing boss and a lower dividing boss, and is symmetrically distributed on the upper and lower end faces of the steel ring;

[0012] The steel ring is a square steel ring.

[0013] The upper part of the conical slip is provided with a steel ring groove. The cross-section of the steel ring groove is T-shaped. The conical slip is embedded in the steel ring of the slip through the steel ring groove. A screw hole is provided below the steel ring groove. The screw hole is arranged longitudinally. The constraint cavity is located outside the screw hole. The lower end of the conical slip has a slip circular inclined surface and a first arc-shaped sawtooth slip tooth inside. The lower end of the conical slip has a first rounded corner transition surface on the inner side.

[0014] The constraint block structure matches the constraint cavity structure. The upper and lower end faces of the constraint block are respectively attached to the upper and lower end faces of the constraint cavity. A screw through hole is opened in the middle of the constraint block at the position corresponding to the screw hole. The screw passes through the screw hole and the screw through hole in sequence.

[0015] The inner wall of the conical slip cylinder is designed with an inverted conical surface structure, and its inner diameter gradually shrinks from the top to the bottom. The conical slip moves up and down along the inner wall of the conical slip cylinder under the action of the lower screw pump rotor.

[0016] The secondary hinge-type slip module B includes a hinge slip cylinder. The upper end of the hinge slip cylinder is threadedly connected to the lower end of the primary adaptive slip module A. The lower end of the hinge slip cylinder is threadedly connected to the guide shoe. Multiple window slots are evenly arranged in the middle of the hinge slip cylinder. Each window slot is equipped with a hinge slip. Each hinge slip is integrally connected to the cylinder wall of the hinge slip cylinder through a circular ring. A cutting groove is opened at the outer end of each hinge slip. The circular ring passes through each cutting groove, and a torsion spring is sleeved on the part of the circular ring located in the cutting groove.

[0017] The outer end of the hinge slip is a semi-cylindrical structure with a hinge through hole in the middle. The inner end of the hinge slip is provided with a second arc-shaped sawtooth slip tooth, which gradually converges from the lower end to the upper end along the central axis of the hinge slip cylinder.

[0018] The hinge slip cylinder has a boss and a protective shell in the middle of the window groove. The two ends of the torsion spring are at 90°. One end of the torsion spring extends into a horizontal small hole in the cutting groove, and the other end is fixed and constrained by the boss and protective shell of the hinge slip cylinder.

[0019] The inner end of the hinge slip is provided with a second rounded transition surface at both the upper and lower ends of the second arc-shaped sawtooth slip tooth;

[0020] Each window slot has a through hole along the circumference of the hinge slip cylinder on its side wall for the circular ring to pass through, and a transition flared opening is provided on the inner side of the lower end of the hinge slip cylinder.

[0021] The lower end of the shoe is provided with a vertical guide surface and a spiral guide surface, with one end of the spiral guide surface located below the vertical guide surface.

[0022] The beneficial effects of this utility model are:

[0023] This utility model discloses a two-stage slip-type well-dumping screw pump rotor retrieval tool, comprising a first-stage adaptive slip module A, a second-stage hinge slip module B, and a guide shoe. The first-stage adaptive slip module A, with multiple conical slips, can move upward along the inner conical surface of the conical slip cylinder under the jacking force of the lower screw pump rotor, and open radially along the slip steel ring. Under the action of the gravity of the conical slips and the lifting force of the tubing string, the multiple conical slips circumferentially lock the screw pump rotor.

[0024] The two-stage hinge-type slip module B of this utility model has multiple hinge slips that can overcome the elastic force of the torsion spring and open under the pushing force of the lower screw pump rotor. The arc-shaped sawtooth slip teeth of the hinge slips contact the screw pump rotor with the maximum area. When the two-stage slip-type well-drop screw pump rotor retrieval tool is lifted, the second arc-shaped sawtooth slip teeth tightly bite the screw pump rotor along the circumference of the screw pump rotor.

[0025] The guide shoe of this utility model has a vertical guide surface and a spiral guide surface at the lower end, which can guide the falling fish into the guide shoe along a spiral trajectory. At the same time, it helps to position and straighten the tilted fish top in the well barrel during the retrieval process, thereby improving the retrieval success rate.

[0026] This utility model, through different types of primary adaptive slip module A, secondary hinge slip module B, and guide shoe, can lock the smooth screw pump rotor from multiple angles and in all directions, enabling successful retrieval in one attempt; it has the advantages of simple structure, long service life, safety and high efficiency. Attached Figure Description

[0027] Figure 1 This is a schematic cross-sectional view of the structure of this utility model;

[0028] Figure 2 This is a schematic diagram of the steel ring structure of the present invention;

[0029] Figure 3 This is a schematic diagram of the screw structure of this utility model;

[0030] Figure 4 This is a schematic diagram of the constraint block structure of this utility model;

[0031] Figure 5 This is a schematic diagram of the conical clamp structure of this utility model;

[0032] Figure 6(a) Schematic diagram of the first-stage slip system of this utility model;

[0033] Figure 6(b) is a cross-sectional view of the present invention as shown in Figure 6(a);

[0034] Figure 7(a) is a schematic diagram of the hinge slip cylinder structure of this utility model;

[0035] Figure 7(b) is a side view of the hinge slip cylinder of this utility model;

[0036] Figure 7(c) is a cross-sectional view of DD in Figure 7(b) of this utility model;

[0037] Figure 8 This is a schematic diagram of the torsion spring structure of this utility model;

[0038] Figure 9 This is a schematic diagram of the hinge clip structure of this utility model;

[0039] Figure 10(a) is a schematic diagram of the three-stage hinge slip system of this utility model;

[0040] Figure 10(b) is a cross-sectional view of CC in Figure 10(a) of this utility model;

[0041] Figures 11(a) and 11(b) are schematic diagrams of the shoe structure of this utility model;

[0042] Figure 12 This is a structural cross-sectional schematic diagram of the rotor of the salvage screw pump of this utility model, showing three processes: (a), (b), and (c).

[0043] In the diagram, 1. upper connector, 2. conical slip cylinder;

[0044] 3. Slip ring, 3-1. Separating boss, 3-2. Steel ring;

[0045] 4. Screw, 4-1. Slotted head, 4-2. Screw head, 4-3. Screw body;

[0046] 5. Constraint block; 5-1. Arc end face; 5-2. Arc side face; 5-3. Screw through hole; 5-4. Trapezoidal section;

[0047] 6. Conical slip, 6-1. Steel ring groove, 6-2. Constraint cavity, 6-3. Screw hole, 6-4. Slip circular bevel, 6-5. First arc-shaped sawtooth slip tooth, 6-6. First rounded transition surface;

[0048] 7. Hinge slip cylinder; 7-1. Window groove; 7-2. Boss; 7-3. Through hole; 7-4. Transition flared mouth;

[0049] 8. Torsion spring, 8-1. Vertical end of torsion spring, 8-2. Torsion spring coil, 8-3. Horizontal end of torsion spring;

[0050] 9. Circular ring; 10. Hinge slip; 10-1. Second rounded corner transition surface; 10-2. Second arc-shaped sawtooth slip tooth; 10-3. Hinge through hole; 10-4. Semi-cylindrical surface; 10-5. Cutting groove;

[0051] 11. Shoe guide, 11-1. Shoe guide nut, 11-2. Vertical guide surface, 11-3. Spiral guide surface;

[0052] 12-Screw pump rotor, 13. Screw pump lower end housing, 14. Protector, 15. Motor unit, 16. Oil pipe. Detailed Implementation

[0053] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0054] Example 1

[0055] This utility model relates to a two-stage slip-type well-dumping screw pump rotor retrieval tool, the structure of which is as follows: Figure 1 As shown, the main body is a cylindrical structure, consisting of an upper connector 1, a primary adaptive locking module A, a secondary hinged locking module B, and a guide shoe 11 connected in sequence.

[0056] Example 2

[0057] Based on Example 1, and considering the structure and technical characteristics of the two-stage slip-type well-dumping screw pump rotor fishing tool, the specific implementation method will be described in the following description from the top to the bottom of the fishing tool, namely, the upper connector 1, the first-stage adaptive slip module A, the second-stage hinge slip module B, and the guide shoe 11.

[0058] Specifically, the specific structure of the upper connector 1 is as follows: Figure 1 and Figure 12 As shown in (a), the lower end of the upper connector 1 is connected to the upper end of the tapered slip cylinder 2 of the first-stage adaptive slip module A by a thread. The inner diameter of the lower end of the upper connector 1 is smaller than the inner diameter of the slip steel ring 3, which is used to constrain the slip steel ring 3 and the tapered slip 6. The upper end of the upper connector 1 is used to connect the fishing string that is lowered into the well, so that they are connected as one unit.

[0059] like Figure 1 and Figure 12As shown, the first-level adaptive slip module A includes a conical slip cylinder 2, a slip steel ring 3, screws 4, constraint blocks 5, and conical slips 6. The conical slip cylinder 2 houses the slip steel ring 3, on which multiple conical slips 6 are evenly distributed. The outer wall of each conical slip 6 is tightly fitted to the inner wall of the conical slip cylinder 2. The inner diameter of the lower end of the upper connector 1 is smaller than the inner diameter of the slip steel ring 3. Each conical slip 6 has a constraint cavity 6-2, and a constraint block 5 is installed within each constraint cavity 6-2. The constraint block 5 is fixed within the constraint cavity 6-2 of the conical slip 6 by screws 4. Screws 4 are used to tighten and fix the constraint block 5 and the conical slip 6, and the constraint block 5 is used to prevent the conical slip 6 from disengaging from the slip steel ring 3. The upper end of the conical slip cylinder 2 has a threaded female thread, which is threadedly connected to the lower end of the upper connector 1. The inner diameter of the lower end of the upper connector 1 is smaller than the inner diameter of the slip steel ring 3.

[0060] Example 3

[0061] Based on Example 2, specifically, the specific structure of the conical slip cylinder 2 is as follows: Figure 1 , Figure 12 (b) and Figure 12 As shown in (c), the inner side of the conical slip cylinder 2 is configured with an inverted conical surface structure, and its inner diameter gradually shrinks from the upper end to the lower end, so that the outer wall of the conical slip 6 is tightly attached to the inner wall of the conical slip cylinder 2. Under the thrust of the lower screw pump rotor 12, it moves upward along the inner wall of the conical slip cylinder 2 and opens radially along the slip steel ring 3. The lower end of the conical slip cylinder 2 is provided with a threaded male thread, which is threadedly connected to the upper female thread of the hinge slip cylinder 7.

[0062] like Figure 2 As shown, the clamping steel ring 3 includes a separating boss 3-1 and a steel ring 3-2. There are multiple separating bosses 3-1, and their number corresponds to the number of constraining conical clamps 6. The multiple conical clamps 6 are evenly separated by the separating bosses 3-1. The separating bosses 3-1 are evenly and vertically arranged on the end face of the steel ring 3-2.

[0063] Preferably, the dividing boss 3-1 consists of an upper dividing boss and a lower dividing boss, and is symmetrically distributed on the upper and lower end faces of the steel ring 3-2. The upper and lower dividing bosses serve two purposes: to separate the parts and to limit the swing of the conical slip 6.

[0064] Preferably, steel ring 3-2 is a square steel ring.

[0065] Preferably, there are six of each of the following components: the dividing boss 3-1, the screw 4, the constraint block 5, and the conical slip 6.

[0066] Preferably, the circular ring 9 is made of circular iron wire, but it can also be made of other rigid materials.

[0067] Example 4

[0068] Based on Example 3, the specific structure of the conical slip 6 is as follows: Figure 5 Figures 6(a), 6(b) and Figure 12 As shown in (c), the body of the conical slip 6 is conical, and a steel ring groove 6-1 with a T-shaped cross-section is provided at the upper end of its body. Six conical slips 6 are evenly embedded in the square steel ring 3-2 of the slip steel ring 3 by means of the steel ring groove 6-1. The multiple conical slips 6 are evenly separated by the dividing bosses 3-1 of the slip steel ring 3. A screw hole 6-3 is provided below the steel ring groove 6-1. The screw hole 6-3 is arranged longitudinally, and a constraint cavity 6-2 is provided on the outside of the screw hole 6-3. The lower end of the conical slip 6 body has a slip circular inclined surface 6-4, which matches the taper of the conical slip cylinder 2. The inside has a first arc surface sawtooth slip tooth 6-5. A first rounded corner transition surface 6-6 is provided on the inner end face of the lower end of the conical slip 6 body, which is conducive to introducing the screw pump rotor 12 into the conical slip 6.

[0069] After the screw pump rotor is lowered into the well, it may experience local deformation, bending, or surface damage due to collision and wear. However, the elastic contraction characteristics of the conical slip 6 allow it to adapt to changes in the rotor's outer diameter within a certain range.

[0070] When the tool is lowered to the rotor position and an upward pulling force is applied, the conical slip 6 moves upward along the inner wall of the conical slip cylinder 2 under the action of axial force. Due to the conical fit, radial contraction occurs, which automatically clamps the outer surface of the screw pump rotor 12.

[0071] The action of the conical slip 6 relies on the axial tension of the retrieval tool and the gravity during descent. It automatically contracts and tightens when lifted and releases when lowered, requiring no additional hydraulic or mechanical drive devices. It has a simple structure and high reliability, making it particularly suitable for complex downhole environments such as high temperature, high pressure, and sand-containing well fluids, reducing the probability of retrieval failure due to mechanical failure.

[0072] Furthermore, such as Figure 4 As shown, the constraint block 5 has an arc-shaped structure that matches the structure of the constraint cavity 6-2. The cross-section of the arc-shaped structure is a trapezoidal section 5-4, and both the inner and outer sides of the arc-shaped structure have inward-facing arc-shaped sides 5-2. A screw through-hole 5-3 is provided in the middle of the arc-shaped structure, and the position of the screw through-hole 5-3 corresponds to the position of the screw hole 6-3. The screw 4 is installed in the screw through-hole 5-3 of the constraint block 5 and the screw hole 6-3 of the conical clip 6, thereby fixing the constraint block 5 in the constraint cavity 6-2. Figure 4 and Figure 5 As shown, the two arc-shaped end faces 5-1 at the top and bottom of the arc-shaped structure are inclined inward along the arc. During installation, they should fit against the upper and lower end faces of the constraint cavity 6-2 of the conical slip 6, while the arc-shaped side face 5-2 of the constraint block should be tightly attached to the constraint cavity 6-2 of the conical slip 6. The constraint block 5 is used to constrain the conical slip 6 to prevent it from coming out of the slip steel ring 3.

[0073] Under the thrust of the lower screw pump rotor 12, the six conical slips 6 move upward along the inner wall of the conical slip cylinder 2 and open radially along the slip steel ring 3, encircling the screw pump rotor 12. Under the action of the gravity of the conical slip system and the lifting force of the tubing string, the six conical slips 6 slide downward and circumferentially lock the screw pump rotor 12. When the secondary slip type well-drop screw pump rotor retrieval tool is lifted, the six conical slips 6 contract radially along the slip steel ring 3, so that their slip teeth tightly lock the screw pump rotor 12. That is, the first-stage adaptive slip module A plays a role, and successful retrieval can be achieved.

[0074] Example 5

[0075] Based on Example 4, preferably, such as Figure 3 As shown, screw 4 includes a slotted groove 4-1, a screw head 4-2, and a screw body 4-3. The screw head 4-2 is provided at the upper end of the screw body 4-3, and a slotted groove 4-1 is formed on the screw head 4-2. The purpose of using a slotted screw is to reduce the gap on the first-stage adaptive slip module A.

[0076] The screw 4 is inserted into the slot 4-1 by a special tool, which drives the screw head 4-2 to rotate, so that the screw body 4-3 rotates into the screw through hole 5-3 of the constraint block 5 and the screw hole 6-3 of the tapered collet 6, for tightening and fixing the constraint block 5 and the tapered collet 6.

[0077] Example 6

[0078] Based on Example 5, the two-stage hinge-type slip module B includes a hinge slip cylinder 7, a torsion spring 8, a circular ring 9, and a hinge slip 10.

[0079] Specifically, the specific structure of the hinge lock cylinder 7, such as Figure 1 Figures 7(a), 7(b), 7(c) and Figure 12 As shown in (b), the upper end of the hinge slip cylinder 7 is provided with a threaded female thread for connecting the lower end of the tapered slip cylinder 2 with a threaded male thread. Multiple window slots 7-1 are evenly provided in the middle of the hinge slip cylinder 7, and a hinge slip 10 is provided in each window slot 7-1. Each hinge slip 10 is connected to the cylinder wall of the hinge slip cylinder 7 by a ring 9. The ring 9 passes through the cutting groove 10-5 at the outer end of each hinge slip 10, and a torsion spring 8 is provided on the part of the ring 9 located in the cutting groove 10-5.

[0080] Example 7

[0081] Based on embodiment 6, each window slot 7-1 has a through hole 7-3 on its side wall along the circumference of the hinge slip cylinder 7. Each through hole 7-3 is located on an arc trajectory formed with a point on the central axis of the hinge slip cylinder 7 as the center. The ring 9 passes through each through hole 7-3 and each hinge slip 10 to constrain the six evenly distributed hinge slips 10, so that they can only rotate around the ring 9 as the axis under the action of external force.

[0082] The hinge slip cylinder 7 has a boss 7-2 and a protective shell located outside the window groove 7-1 in the middle, which are used to restrain the torsion spring 8 and prevent the hinge slip 10 and the torsion spring 8 from falling from the outer side of the window groove of the hinge slip cylinder 7 into the "tubing-casing" annulus (in the wellbore) under the action of external force.

[0083] The lower outer side of the hinge slip cylinder 7 is provided with a threaded male buckle structure, which is used to connect the threaded female buckle at the upper end of the guide shoe 11, so that they are connected as one.

[0084] The hinge slip cylinder 7 has a transition flared opening 7-4 on the inner side of its lower end, which facilitates the entry of the screw pump rotor 12 into the interior.

[0085] Example 8

[0086] Based on Example 7, specifically, the specific structure of the hinge clasp 10 is as follows: Figure 1 , Figure 9 Figure 10(a), Figure 10(b) Figure 12 (a) and Figure 12 As shown in (b). The longitudinal section of the hinge slip 10 is square, which is convenient for being placed in the window groove 7-1 in the middle of the hinge slip cylinder 7. The outer end is a semi-cylindrical structure for rotating along the circular wire ring 9. The middle of the outer end is provided with a hinge through hole 10-3, through which the circular ring 9 can pass, so that the hinge slip 10 can rotate along the circular ring 9. The inner end is a second arc-shaped sawtooth slip tooth 10-2. The second arc-shaped sawtooth slip tooth 10-2 gradually converges from the lower end to the upper end along the central axis of the hinge slip cylinder 7, which is convenient for the screw pump rotor 12 to push open the six evenly distributed hinge slips 10. It is also more conducive to the six evenly distributed hinge slips 10 contacting the screw pump rotor 12 with the largest area, lifting the two-stage slip type well-drop screw pump rotor retrieval tool, and further locking the screw pump rotor 12.

[0087] like Figure 9 As shown, the semi-cylindrical structure has a semi-cylindrical surface 10-4, and the inner end of the hinge slip 10 is provided with a second rounded transition surface 10-1 at both the upper and lower ends of the second arc-shaped sawtooth slip tooth 10-2.

[0088] Specifically, such as Figure 8 Figure 10(a), Figure 10(b) Figure 12 (a) Figure 12As shown in (b), the torsion spring 8 includes a torsion spring coil 8-2, with the two ends of the torsion spring coil 8-2 at 90°, namely the vertical end 8-1 of the torsion spring and the horizontal end 8-3 of the torsion spring. Six torsion springs 8 are evenly distributed in the middle of the cutting grooves 10-5 of the semi-cylindrical structure at the outer end of the six hinge slips 10. The annular ring 9 passes through the torsion spring coils 8-2 of the six torsion springs 8. The horizontal end 8-3 of the torsion spring is inserted into a small horizontal hole in the cutting groove 10-5 of the hinge slip 10. The vertical end 8-1 of the torsion spring is fixed and constrained by the boss 7-2 of the hinge slip cylinder 7 and the protective shell. Under the upward force of the screw pump rotor 12, the six hinge slips 10 in the naturally closed state are opened. At the same time, the six torsion springs 8 are compressed. The torsion springs 8 rebound and act on the six hinge slips 10, making the six hinge slips 10 tend to close. The secondary slip type well-drop screw pump rotor retrieval tool is lifted, so that the second arc surface sawtooth slip teeth 10-2 tightly bite the screw pump rotor 12. That is, the secondary hinge type slip module B plays a role, and successful retrieval can be achieved.

[0089] After being locked, the hinge slip 10 fits tightly against the surface of the screw pump rotor 12, providing a strong gripping force. Its second arc-shaped sawtooth slip teeth 10-2 are designed to embed into the surface of the screw pump rotor 12, increasing friction and preventing the screw pump rotor 12 from slipping during retrieval. Furthermore, when multiple hinge slips 10 are used together, they can clamp the screw pump rotor 12 from different angles, further improving the gripping strength and stability.

[0090] The hinge and slip 10 have a relatively simple structure and are not prone to serious damage under normal use. Even if some parts are damaged, they can be repaired by replacing the hinges, slip teeth, and other parts, resulting in low maintenance costs. They can be reused multiple times, reducing the cost of salvage operations.

[0091] The hinge slip 10 can be adjusted according to the size and shape of the screw pump rotor 12 after it has been lowered into the well. For rotors that have undergone slight deformation after being lowered into the well, the hinge slip can adapt to the changes in shape by opening and closing and adjusting itself, ensuring a certain gripping effect. Compared with integral slips, it is more adaptable to different working conditions.

[0092] Example 9

[0093] Based on Example 8, specifically, as follows: Figure 1As shown in Figures 11(a) and 11(b), the upper end of the guide shoe 11 is provided with a threaded guide shoe female buckle 11-1, which is used to connect the male buckle at the lower end of the hinge slip cylinder 7. The lower end of the guide shoe 11 is provided with a vertical guide surface 11-2 and a spiral guide surface 11-3. One end of the spiral guide surface 11-3 is located at the lower end of the vertical guide surface 11-2, which helps to position and straighten the tilted fish top in the well barrel during the retrieval process. At the same time, it can guide the fallen fish along the spiral trajectory into the guide shoe 11, so that the fallen object enters the retrieval tool and improves the retrieval success rate.

[0094] The first-level adaptive slip module A has multiple conical slips that, under the thrust of the lower screw pump rotor, can move up along the inner conical surface of the conical slip cylinder and open radially along the slip steel ring. Under the action of the gravity of the conical slips and the lifting force of the tubing, the multiple conical slips circumferentially lock the screw pump rotor.

[0095] The secondary hinge-type slip module B has multiple hinge slips that can open under the jacking force of the lower screw pump rotor, overcoming the elastic force of the torsion spring. The arc-shaped sawtooth slip teeth of the hinge slips contact the screw pump rotor with the maximum area. When the secondary slip-type well-dumping screw pump rotor retrieval tool is lifted, the second arc-shaped sawtooth slip teeth tightly grip the screw pump rotor along the circumference of the screw pump rotor.

[0096] like Figure 12 As shown, the lower end of the screw pump rotor 12 is sequentially equipped with a screw pump lower end housing 13, a protector 14, a motor unit 15, an oil pipe 16, and a fall protection device. The specific connection method and the structure of the fall protection device are common knowledge in this field and will not be described in detail here.

[0097] Screw pump rotor 12: As the core moving part of the screw pump, it realizes the suction and discharge of fluid through rotation. The components connected to its lower end need to cooperate with its movement and provide protection, power and other support.

[0098] The lower casing 13 of the screw pump mainly serves to accommodate and protect the lower part of the rotor structure. It may also be connected to the pump's suction chamber and other parts to ensure the normal flow path of the fluid.

[0099] Protector 14: This is a key protective component in the screw pump system, and its functions include:

[0100] To prevent well fluid from entering the motor and thus avoid damage to it;

[0101] Balance the pressure inside and outside the motor to reduce the pressure load on the motor housing;

[0102] Provides lubrication for motor bearings, extending the motor's service life.

[0103] Motor unit 15: Provides power for the operation of the screw pump, and realizes oil pumping operation by driving the rotor to rotate. It is the power core of the entire system.

[0104] Tubing 16: Used to transport the fluid pumped by the screw pump to the surface. It is the channel for the fluid to rise. Its specifications and strength need to be designed according to parameters such as well conditions and discharge rate.

[0105] Fall protection device: Installed at the bottom, it mainly serves a safety protection function. When the downhole device accidentally falls off, it can prevent the parts from falling to the bottom of the well, avoiding damage to the well casing. It also facilitates later retrieval and maintenance.

[0106] This utility model, through different types of primary adaptive slip module A, secondary hinge slip module B, and guide shoe, can lock the smooth screw pump rotor from multiple angles and in all directions, enabling successful retrieval in one attempt; it has the advantages of simple structure, long service life, safety and high efficiency.

[0107] Example 10

[0108] This utility model relates to a two-stage slip-type well-dumping screw pump rotor retrieval tool, the structure of which is as follows: Figure 1 As shown, the main body is a cylindrical structure, consisting of an upper connector 1, a primary adaptive locking module A, a secondary hinged locking module B, and a guide shoe 11 connected in sequence.

[0109] Specifically, the specific structure of the upper connector 1 is as follows: Figure 1 and Figure 12 As shown in (a), the lower end of the upper connector 1 is connected to the upper end of the tapered slip cylinder 2 of the first-stage adaptive slip module A by a thread. The inner diameter of the lower end of the upper connector 1 is smaller than the inner diameter of the slip steel ring 3, which is used to constrain the slip steel ring 3 and the tapered slip 6. The upper end of the upper connector 1 is used to connect the fishing string that is lowered into the well, so that they are connected as one unit.

[0110] like Figure 1 and Figure 12 As shown, the first-level adaptive slip module A includes a conical slip cylinder 2, a slip steel ring 3, screws 4, constraint blocks 5, and conical slips 6. The conical slip cylinder 2 houses the slip steel ring 3, on which multiple conical slips 6 are evenly distributed. The outer wall of each conical slip 6 is tightly fitted to the inner wall of the conical slip cylinder 2. The inner diameter of the lower end of the upper connector 1 is smaller than the inner diameter of the slip steel ring 3. Each conical slip 6 has a constraint cavity 6-2, and a constraint block 5 is installed within each constraint cavity 6-2. The constraint block 5 is fixed within the constraint cavity 6-2 of the conical slip 6 by screws 4. Screws 4 are used to tighten and fix the constraint block 5 and the conical slip 6, and the constraint block 5 is used to prevent the conical slip 6 from disengaging from the slip steel ring 3. The upper end of the conical slip cylinder 2 has a threaded female thread, which is threadedly connected to the lower end of the upper connector 1. The inner diameter of the lower end of the upper connector 1 is smaller than the inner diameter of the slip steel ring 3.

[0111] The specific structure of the conical slip cylinder 2 is as follows: Figure 1 , Figure 12 (b) and Figure 12 As shown in (c), the inner side of the conical slip cylinder 2 is configured with an inverted conical surface structure, and its inner diameter gradually shrinks from the upper end to the lower end, so that the outer wall of the conical slip 6 is tightly attached to the inner wall of the conical slip cylinder 2. Under the thrust of the lower screw pump rotor 12, it moves upward along the inner wall of the conical slip cylinder 2 and opens radially along the slip steel ring 3. The lower end of the conical slip cylinder 2 is provided with a threaded male thread, which is threadedly connected to the upper female thread of the hinge slip cylinder 7.

[0112] The slip ring 3 includes a partition boss 3-1 and a steel ring 3-2. There are multiple partition bosses 3-1, and their number corresponds to the number of constraint conical slips 6. The multiple conical slips 6 are evenly separated by the partition bosses 3-1. The partition bosses 3-1 are evenly and vertically arranged on the end face of the steel ring 3-2.

[0113] The specific structure of the conical chuck 6 is as follows: Figure 5 Figures 6(a), 6(b) and Figure 12 As shown in (c), the conical slip 6 has a conical body with a steel ring groove 6-1 at its upper end. The groove has a T-shaped cross-section. Each conical slip 6 is evenly embedded in the square steel ring 3-2 of the slip steel ring 3 by the steel ring groove 6-1. Multiple conical slips 6 are evenly separated by the dividing bosses 3-1 of the slip steel ring 3. A screw hole 6-3 is provided below the steel ring groove 6-1. The screw hole 6-3 is arranged longitudinally, and a constraint cavity 6-2 is provided on the outside of the screw hole 6-3. The lower end of the conical slip 6 has a slip circular inclined surface 6-4 on the outside and a first arc-shaped sawtooth slip tooth 6-5 on the inside. A first rounded transition surface 6-6 is provided on the inner end face of the lower end of the conical slip 6, which is conducive to introducing the screw pump rotor 12 into the conical slip 6.

[0114] When the tool is lowered to the rotor position and an upward pulling force is applied, the conical slip 6 moves upward along the inner wall of the conical slip cylinder 2 under the action of axial force. Due to the conical fit, radial contraction occurs, which automatically clamps the outer surface of the screw pump rotor 12.

[0115] The action of the conical slip 6 relies on the axial tension of the retrieval tool and the gravity during descent. It automatically contracts and tightens when lifted and releases when lowered, requiring no additional hydraulic or mechanical drive devices. It has a simple structure and high reliability, making it particularly suitable for complex downhole environments such as high temperature, high pressure, and sand-containing well fluids, reducing the probability of retrieval failure due to mechanical failure.

[0116] The constraint block 5 has an arc-shaped structure that matches the structure of the constraint cavity 6-2. The cross-section of the arc-shaped structure is a trapezoidal section 5-4, and both the inner and outer sides of the arc-shaped structure have inward-facing arc-shaped sides 5-2. A screw through-hole 5-3 is provided in the middle of the arc-shaped structure, and the position of the screw through-hole 5-3 corresponds to the position of the screw hole 6-3. The screw 4 is installed in the screw through-hole 5-3 of the constraint block 5 and the screw hole 6-3 of the tapered clip 6, thereby fixing the constraint block 5 in the constraint cavity 6-2. Figure 4 and Figure 5 As shown, the two arc-shaped end faces 5-1 at the top and bottom of the arc-shaped structure are inclined inward along the arc. During installation, they should fit against the upper and lower end faces of the constraint cavity 6-2 of the conical slip 6, while the arc-shaped side face 5-2 of the constraint block should be tightly attached to the constraint cavity 6-2 of the conical slip 6. The constraint block 5 is used to constrain the conical slip 6 to prevent it from coming out of the slip steel ring 3.

[0117] The secondary hinge type slip module B includes a hinge slip cylinder 7, a torsion spring 8, a circular ring 9, and a hinge slip 10.

[0118] Specifically, the specific structure of the hinge lock cylinder 7, such as Figure 1 Figures 7(a), 7(b), 7(c) and Figure 12 As shown in (b), the upper end of the hinge slip cylinder 7 is provided with a threaded female thread for connecting the lower end of the tapered slip cylinder 2 with a threaded male thread. Multiple window slots 7-1 are evenly provided in the middle of the hinge slip cylinder 7, and a hinge slip 10 is provided in each window slot 7-1. Each hinge slip 10 is connected to the cylinder wall of the hinge slip cylinder 7 by a ring 9. The ring 9 passes through the cutting groove 10-5 at the outer end of each hinge slip 10, and a torsion spring 8 is provided on the part of the ring 9 located in the cutting groove 10-5.

[0119] Each window groove 7-1 has a through hole 7-3 on its side wall along the circumference of the hinge slip cylinder 7. Each through hole 7-3 is located on an arc trajectory formed with a point on the central axis of the hinge slip cylinder 7 as the center. The ring 9 passes through each through hole 7-3 to constrain the six evenly distributed hinge slips 10, so that they can only rotate around the ring 9 as the axis under the action of external force.

[0120] The hinge slip cylinder 7 has a boss 7-2 and a protective shell located outside the window groove 7-1 in the middle, which are used to restrain the torsion spring 8 and prevent the hinge slip 10 and the torsion spring 8 from falling from the outer side of the window groove of the hinge slip cylinder 7 into the "tubing-casing" annulus (in the wellbore) under the action of external force.

[0121] The lower outer side of the hinge slip cylinder 7 is provided with a threaded male buckle structure, which is used to connect the threaded female buckle at the upper end of the guide shoe 11, so that they are connected as one.

[0122] The hinge slip cylinder 7 has a transition flared opening 7-4 on the inner side of its lower end, which facilitates the entry of the screw pump rotor 12 into the interior.

[0123] The specific structure of the hinge Kava 10, such as Figure 1 , Figure 9 Figure 10(a), Figure 10(b) Figure 12 (a) and Figure 12 As shown in (b). The longitudinal section of the hinge slip 10 is square, which is convenient for being placed in the window groove 7-1 in the middle of the hinge slip cylinder 7. The outer end is a semi-cylindrical structure for rotating along the circular wire ring 9. The middle of the outer end is provided with a hinge through hole 10-3, through which the circular ring 9 can pass, so that the hinge slip 10 can rotate along the circular ring 9. The inner end is a second arc-shaped sawtooth slip tooth 10-2. The second arc-shaped sawtooth slip tooth 10-2 gradually converges from the lower end to the upper end along the central axis of the hinge slip cylinder 7, which is convenient for the screw pump rotor 12 to push open the six evenly distributed hinge slips 10. It is also more conducive to the six evenly distributed hinge slips 10 contacting the screw pump rotor 12 with the largest area, lifting the two-stage slip type well-drop screw pump rotor retrieval tool, and further locking the screw pump rotor 12.

[0124] like Figure 9 As shown, the semi-cylindrical structure has a semi-cylindrical surface 10-4, and the inner end of the hinge slip 10 is provided with a second rounded transition surface 10-1 at both the upper and lower ends of the second arc-shaped sawtooth slip tooth 10-2.

[0125] After being locked, the hinge slip 10 fits tightly against the surface of the screw pump rotor 12, providing a strong gripping force. Its second arc-shaped sawtooth slip teeth 10-2 are designed to embed into the surface of the screw pump rotor 12, increasing friction and preventing the screw pump rotor 12 from slipping during retrieval. Furthermore, when multiple hinge slips 10 are used together, they can clamp the screw pump rotor 12 from different angles, further improving the gripping strength and stability.

[0126] The hinge and slip 10 have a relatively simple structure and are not prone to serious damage under normal use. Even if some parts are damaged, they can be repaired by replacing the hinges, slip teeth, and other parts, resulting in low maintenance costs. They can be reused multiple times, reducing the cost of salvage operations.

[0127] The hinge slip 10 can be adjusted according to the size and shape of the screw pump rotor 12 after it has been lowered into the well. For rotors that have undergone slight deformation after being lowered into the well, the hinge slip can adapt to the changes in shape by opening and closing and adjusting itself, ensuring a certain gripping effect. Compared with integral slips, it is more adaptable to different working conditions.

[0128] Specifically, such as Figure 8 Figure 10(a), Figure 10(b) Figure 12 (a) Figure 12As shown in (b), the torsion spring 8 includes a torsion spring coil 8-2, with the two ends of the torsion spring coil 8-2 at 90°, namely the vertical end 8-1 of the torsion spring and the horizontal end 8-3 of the torsion spring. Six torsion springs 8 are evenly distributed in the middle of the cutting grooves 10-5 of the semi-cylindrical structure at the outer end of the six hinge slips 10. The annular ring 9 passes through the torsion spring coils 8-2 of the six torsion springs 8. The horizontal end 8-3 of the torsion spring is inserted into a small horizontal hole in the cutting groove 10-5 of the hinge slip 10. The vertical end 8-1 of the torsion spring is fixed and constrained by the boss 7-2 of the hinge slip cylinder 7 and the protective shell. Under the upward force of the screw pump rotor 12, the six hinge slips 10 in the naturally closed state are opened. At the same time, the six torsion springs 8 are compressed. The torsion springs 8 rebound and act on the six hinge slips 10, making the six hinge slips 10 tend to close. The secondary slip type well-drop screw pump rotor retrieval tool is lifted, so that the second arc surface sawtooth slip teeth 10-2 tightly bite the screw pump rotor 12. That is, the secondary hinge type slip module B plays a role, and successful retrieval can be achieved.

[0129] Example 11

[0130] This utility model relates to a two-stage slip-type well-dumping screw pump rotor retrieval tool, the structure of which is as follows: Figure 1 As shown, the main body is a cylindrical structure, consisting of an upper connector 1, a primary adaptive locking module A, a secondary hinged locking module B, and a guide shoe 11 connected in sequence.

[0131] The first-level adaptive slip module A includes a conical slip cylinder 2, a slip steel ring 3, screws 4, constraint blocks 5, and conical slips 6. The conical slip cylinder 2 contains the slip steel ring 3, on which multiple conical slips 6 are evenly distributed. The outer wall of each conical slip 6 is tightly fitted to the inner wall of the conical slip cylinder 2. The inner diameter of the lower end of the upper connector 1 is smaller than the inner diameter of the slip steel ring 3. Each conical slip 6 has a constraint cavity 6-2, and a constraint block 5 is installed in each constraint cavity 6-2. The constraint block 5 is fixed to the constraint cavity 6-2 of the conical slip 6 by screws 4. Screws 4 are used to tighten and fix the constraint block 5 and the conical slip 6, and the constraint block 5 is used to prevent the conical slip 6 from disengaging from the slip steel ring 3. The upper end of the conical slip cylinder 2 has a threaded female thread, which is threaded to the lower end of the upper connector 1. The inner diameter of the lower end of the upper connector 1 is smaller than the inner diameter of the slip steel ring 3.

[0132] The specific structure of the conical slip cylinder 2 is as follows: Figure 1 , Figure 12 (b) and Figure 12As shown in (c), the inner side of the conical slip cylinder 2 is configured with an inverted conical surface structure, and its inner diameter gradually shrinks from the upper end to the lower end, so that the outer wall of the conical slip 6 is tightly attached to the inner wall of the conical slip cylinder 2. Under the thrust of the lower screw pump rotor 12, it moves upward along the inner wall of the conical slip cylinder 2 and opens radially along the slip steel ring 3. The lower end of the conical slip cylinder 2 is provided with a threaded male thread, which is threadedly connected to the upper female thread of the hinge slip cylinder 7.

[0133] The specific structure of the conical chuck 6 is as follows: Figure 5 Figures 6(a), 6(b) and Figure 12 As shown in (c), the conical slip 6 has a conical body with a steel ring groove 6-1 at its upper end. The groove has a T-shaped cross-section. Six conical slips 6 are evenly embedded in the square steel ring 3-2 of the slip steel ring 3 by means of the steel ring groove 6-1. The multiple conical slips 6 are evenly separated by the dividing bosses 3-1 of the slip steel ring 3. A screw hole 6-3 is provided below the steel ring groove 6-1. The screw hole 6-3 is arranged longitudinally, and a constraint cavity 6-2 is provided on the outside of the screw hole 6-3. The lower end of the conical slip 6 has a slip circular inclined surface 6-4 on the outside and a first arc surface sawtooth slip tooth 6-5 on the inside. A first rounded transition surface 6-6 is provided on the inner end face of the lower end of the conical slip 6, which is conducive to introducing the screw pump rotor 12 into the conical slip 6.

[0134] When the tool is lowered to the rotor position and an upward pulling force is applied, the conical slip 6 moves upward along the inner wall of the conical slip cylinder 2 under the action of axial force. Due to the conical fit, radial contraction occurs, which automatically clamps the outer surface of the screw pump rotor 12.

[0135] The action of the conical slip 6 relies on the axial tension of the retrieval tool and the gravity during descent. It automatically contracts and tightens when lifted and releases when lowered, requiring no additional hydraulic or mechanical drive devices. It has a simple structure and high reliability, making it particularly suitable for complex downhole environments such as high temperature, high pressure, and sand-containing well fluids, reducing the probability of retrieval failure due to mechanical failure.

[0136] The secondary hinge type slip module B includes a hinge slip cylinder 7, a torsion spring 8, a circular ring 9, and a hinge slip 10.

[0137] Specifically, the specific structure of the hinge lock cylinder 7, such as Figure 1 Figures 7(a), 7(b), 7(c) and Figure 12As shown in (b), the upper end of the hinge slip cylinder 7 is provided with a threaded female thread for connecting the lower end of the tapered slip cylinder 2 with a threaded male thread. Multiple window slots 7-1 are evenly provided in the middle of the hinge slip cylinder 7, and a hinge slip 10 is provided in each window slot 7-1. Each hinge slip 10 is connected to the cylinder wall of the hinge slip cylinder 7 by a ring 9. The ring 9 passes through the cutting groove 10-5 at the outer end of each hinge slip 10, and a torsion spring 8 is provided on the part of the ring 9 located in the cutting groove 10-5.

[0138] The specific structure of the hinge Kava 10, such as Figure 1 , Figure 9 Figure 10(a), Figure 10(b) Figure 12 (a) and Figure 12 As shown in (b). The longitudinal section of the hinge slip 10 is square, which is convenient for being placed in the window groove 7-1 in the middle of the hinge slip cylinder 7. The outer end is a semi-cylindrical structure for rotating along the circular wire ring 9. The middle of the outer end is provided with a hinge through hole 10-3, through which the circular ring 9 can pass, so that the hinge slip 10 can rotate along the circular ring 9. The inner end is a second arc-shaped sawtooth slip tooth 10-2. The second arc-shaped sawtooth slip tooth 10-2 gradually converges from the lower end to the upper end along the central axis of the hinge slip cylinder 7, which is convenient for the screw pump rotor 12 to push open the six evenly distributed hinge slips 10. It is also more conducive to the six evenly distributed hinge slips 10 contacting the screw pump rotor 12 with the largest area, lifting the two-stage slip type well-drop screw pump rotor retrieval tool, and further locking the screw pump rotor 12.

[0139] After being locked, the hinge slip 10 fits tightly against the surface of the screw pump rotor 12, providing a strong gripping force. Its second arc-shaped sawtooth slip teeth 10-2 are designed to embed into the surface of the screw pump rotor 12, increasing friction and preventing the screw pump rotor 12 from slipping during retrieval. Furthermore, when multiple hinge slips 10 are used together, they can clamp the screw pump rotor 12 from different angles, further improving the gripping strength and stability.

[0140] The hinge and slip 10 have a relatively simple structure and are not prone to serious damage under normal use. Even if some parts are damaged, they can be repaired by replacing the hinges, slip teeth, and other parts, resulting in low maintenance costs. They can be reused multiple times, reducing the cost of salvage operations.

[0141] The hinge slip 10 can be adjusted according to the size and shape of the screw pump rotor 12 after it has been lowered into the well. For rotors that have undergone slight deformation after being lowered into the well, the hinge slip can adapt to the changes in shape by opening and closing and adjusting itself, ensuring a certain gripping effect. Compared with integral slips, it is more adaptable to different working conditions.

[0142] Specifically, such as Figure 8 Figure 10(a), Figure 10(b) Figure 12 (a) Figure 12 As shown in (b), the torsion spring 8 includes a torsion spring coil 8-2, with the two ends of the torsion spring coil 8-2 at 90°, namely the vertical end 8-1 of the torsion spring and the horizontal end 8-3 of the torsion spring. Six torsion springs 8 are evenly distributed in the middle of the cutting grooves 10-5 of the semi-cylindrical structure at the outer end of the six hinge slips 10. The annular ring 9 passes through the torsion spring coils 8-2 of the six torsion springs 8. The horizontal end 8-3 of the torsion spring is inserted into a small horizontal hole in the cutting groove 10-5 of the hinge slip 10. The vertical end 8-1 of the torsion spring is fixed and constrained by the boss 7-2 of the hinge slip cylinder 7 and the protective shell. Under the upward force of the screw pump rotor 12, the six hinge slips 10 in the naturally closed state are opened. At the same time, the six torsion springs 8 are compressed. The torsion springs 8 rebound and act on the six hinge slips 10, making the six hinge slips 10 tend to close. The secondary slip type well-drop screw pump rotor retrieval tool is lifted, so that the second arc surface sawtooth slip teeth 10-2 tightly bite the screw pump rotor 12. That is, the secondary hinge type slip module B plays a role, and successful retrieval can be achieved.

[0143] The upper end of the guide shoe 11 is provided with a threaded female guide shoe buckle 11-1, which is used to connect the male buckle at the lower end of the hinge slip cylinder 7. The lower end of the guide shoe 11 is provided with a vertical guide surface 11-2 and a spiral guide surface 11-3. One end of the spiral guide surface 11-3 is located below the vertical guide surface 11-2, which helps to position and straighten the tilted fish top in the well barrel during the retrieval process. At the same time, it can guide the fallen fish along the spiral trajectory into the guide shoe 11, so that the fallen object enters the retrieval tool and improves the retrieval success rate.

[0144] like Figure 12 As shown, the lower end of the screw pump rotor 12 is sequentially equipped with a screw pump lower end housing 13, a protector 14, a motor unit 15, an oil pipe 16, and a fall protection device. The specific connection method and the structure of the fall protection device are common knowledge in this field and will not be described in detail here.

[0145] Example 12

[0146] This utility model relates to a two-stage slip-type well-dumping screw pump rotor retrieval tool, such as... Figure 1 As shown, the main body is a cylindrical structure, consisting of an upper connector 1, a primary adaptive locking module A, a secondary hinged locking module B, and a guide shoe 11.

[0147] Based on the structure and technical characteristics of the two-stage slip-type well-dumping screw pump rotor retrieval tool, the specific implementation method will be described in the following description from the bottom to the top of the retrieval tool, namely, guide shoe 11, two-stage hinge slip module B, one-stage adaptive slip module A, and upper connector 1.

[0148] Specifically, such as Figure 1As shown in Figures 11(a) and 11(b), the upper end of the guide shoe 11 is provided with a threaded female guide shoe buckle 11-1, which is used to connect the male buckle at the lower end of the hinge slip cylinder 7. The lower end of the guide shoe 11 is provided with a vertical guide surface 11-2 and a spiral guide surface 11-3. One end of the spiral guide surface 11-3 is located at the lower end of the vertical guide surface 11-2, which helps to position and straighten the tilted fish top in the well barrel during the retrieval process. At the same time, it can guide the fallen fish along the spiral trajectory into the guide shoe 11, so that the fallen object enters the retrieval tool.

[0149] like Figure 12 As shown, the lower end of the screw pump rotor 12 is sequentially equipped with a screw pump lower end housing 13, a protector 14, a motor unit 15, an oil pipe 16, and a fall protection device. The specific connection method and the structure of the fall protection device are common knowledge in this field and will not be described in detail here.

[0150] The secondary hinge type slip module B includes a hinge slip cylinder 7, a torsion spring 8, a circular wire ring 9, and a hinge slip 10.

[0151] Specifically, the structural diagram and working principle of the hinge lock cylinder 7 are as follows: Figure 1 Figures 7(a), 7(b), 7(c) and Figure 12 As shown in (b), the upper end of the hinge slip cylinder 7 is provided with a threaded female thread structure for connecting to the threaded male thread at the lower end of the tapered slip cylinder 2. Six window slots 7-1 are evenly arranged in the middle for installing six evenly distributed hinge slips 10. The side of the window slot 7-1 is provided with a circular through hole 7-3 with an arc trajectory drilled with a point on the central axis of the hinge slip cylinder 7 as the center, for constraining the six evenly distributed hinge slips 10 so that they are only held in place by the circular wire ring under the action of external force. 9 rotates 90° around the axis; the window slots 7-1 evenly distributed in the middle of the hinge slip cylinder 7 are provided with bosses 7-2 and protective shells on the outside, which are used to restrain the torsion spring 8 and prevent the hinge slip 10 and the torsion spring 8 from falling from the outer side of the window slot of the hinge slip cylinder 7 into the "tubing-casing" annulus (in the wellbore) under the action of external force; the lower end of the hinge slip cylinder 7 is provided with a threaded male thread structure, which is used to connect the threaded female thread at the upper end of the guide shoe 11 to make them connected as one.

[0152] Specifically, the structural diagram and working principle of hinge 10 are as follows: Figure 1 , Figure 9 Figure 10(a), Figure 10(b) Figure 12 (a) and Figure 12As shown in (b). The longitudinal section of the hinge slip 10 is square, which is used to set in the six evenly distributed window slots 7-1 in the middle of the hinge slip cylinder 7. The outer end has a hinge through hole 10-3 in the middle, through which the circular iron wire ring 9 can pass. The outer end is a semi-cylindrical structure for rotating along the circular iron wire ring 9. The inner end is a second arc-shaped sawtooth slip tooth 10-2. The second arc-shaped sawtooth slip tooth 10-2 gradually converges from the lower end to the upper end along the central axis of the hinge slip cylinder 7, which facilitates the screw pump rotor 12 to push open the six evenly distributed hinge slips 10 and is more conducive to the six evenly distributed hinge slips 10 contacting the screw pump rotor 12 with the largest area, lifting the two-stage slip type well-drop screw pump rotor retrieval tool, and further locking the screw pump rotor 12.

[0153] After being locked, the hinge slip 10 fits tightly against the surface of the screw pump rotor 12, providing a strong gripping force. Its second arc-shaped sawtooth slip teeth 10-2 are designed to embed into the surface of the screw pump rotor 12, increasing friction and preventing the screw pump rotor 12 from slipping during retrieval. Furthermore, when multiple hinge slips 10 are used together, they can clamp the screw pump rotor 12 from different angles, further improving the gripping strength and stability.

[0154] The hinge and slip 10 have a relatively simple structure and are not prone to serious damage under normal use. Even if some parts are damaged, they can be repaired by replacing the hinges, slip teeth, and other parts, resulting in low maintenance costs. They can be reused multiple times, reducing the cost of salvage operations.

[0155] The hinge slip 10 can be adjusted according to the size and shape of the screw pump rotor 12 after it has been lowered into the well. For rotors that have undergone slight deformation after being lowered into the well, the hinge slip can adapt to the changes in shape by opening and closing and adjusting itself, ensuring a certain gripping effect. Compared with integral slips, it is more adaptable to different working conditions.

[0156] Specifically, the detailed structural diagram and working principle of the torsion spring 8 are as follows: Figure 8 Figure 10(a), Figure 10(b) Figure 12 (a) Figure 12As shown in (b), six torsion springs 8 are evenly distributed in the middle of the cutting grooves 10-5 of the semi-cylindrical structure at the outer end of the six hinge slips 10, and pass through the circular iron wire ring 9. The two ends of the torsion springs 8 are at 90°. One end is inserted into a horizontal small hole in the cutting groove 10-5 of the hinge slip 10, and the other end is fixed and constrained by the boss 7-2 of the hinge slip cylinder 7 and the protective shell. Under the pushing force of the screw pump rotor 12, the six hinge slips 10 in the naturally closed state are opened. At the same time, the six torsion springs 8 are compressed. The torsion springs 8 rebound and act on the six hinge slips 10, making the six hinge slips 10 tend to close. The second arc-shaped sawtooth slip teeth 10-2 tightly hold the screw pump rotor 12. The second-stage slip type well-drop screw pump rotor retrieval tool is lifted, so that the second arc-shaped sawtooth slip teeth 10-2 tightly bite the screw pump rotor 12. That is, the second-stage hinge type slip module B plays a role and can achieve successful retrieval.

[0157] The first-level adaptive slip module A includes a conical slip cylinder 2, a slip steel ring 3, a screw 4, a constraint block 5, and a conical slip 6.

[0158] Specifically, the detailed structural diagram and principle of the conical slip cylinder 2 are as follows: Figure 1 , Figure 12 (b) and Figure 12 As shown in (c), the upper end of the conical slip cylinder 2 has a female thread structure, which is connected to the lower end of the upper connector 1 with a male thread; the inner side of the middle part of the conical slip cylinder 2 has an inverted conical surface structure, so that the outer wall of the conical slip 6 fits against the inner wall of the conical slip cylinder 2. Under the thrust of the lower screw pump rotor 12, it moves upward along the inner wall of the conical slip cylinder 2 and opens radially along the slip steel ring 3; the lower end of the conical slip cylinder 2 has a male thread structure, which is connected to the upper end of the hinge slip cylinder 7 with a female and male thread.

[0159] Specifically, such as Figure 2 As shown, six conical slips 6 are evenly embedded in the slip steel ring 3 and are evenly separated by the dividing protrusions 3-1 of the slip steel ring 3; as Figure 5 Figures 6(a), 6(b) and Figure 12As shown in (c), the constraint block 5 is installed inside the constraint cavity of the conical slip 6, and the screw 4 is installed in the screw through hole 5-3 of the constraint block 5 and the screw hole 6-3 of the conical slip 6, for tightening and fixing the constraint block 5 and the conical slip 6. The constraint block 5 is used to constrain the conical slip 6 from disengaging from the slip steel ring 3. Under the thrust of the lower screw pump rotor 12, the six conical slips 6 move upward along the inner wall of the conical slip cylinder 2 and open radially along the slip steel ring 3, encircling the screw pump rotor 12. Under the action of the gravity of the conical slip system and the lifting force of the tubing string, the six conical slips 6 circumferentially lock the screw pump rotor 12 when sliding downward. When the secondary slip type well-falling screw pump rotor retrieval tool is lifted, the six conical slips 6 contract radially along the slip steel ring 3, so that their slip teeth tightly lock the screw pump rotor 12. That is, the first-stage adaptive slip module A plays a role, and successful retrieval can be achieved.

[0160] When the tool is lowered to the rotor position and an upward pulling force is applied, the conical slip 6 moves upward along the inner wall of the conical slip cylinder 2 under the action of axial force. Due to the conical fit, radial contraction occurs, which automatically clamps the outer surface of the screw pump rotor 12.

[0161] The action of the conical slip 6 relies on the axial tension of the retrieval tool and the gravity during descent. It automatically contracts and tightens when lifted and releases when lowered, requiring no additional hydraulic or mechanical drive devices. It has a simple structure and high reliability, making it particularly suitable for complex downhole environments such as high temperature, high pressure, and sand-containing well fluids, reducing the probability of retrieval failure due to mechanical failure.

[0162] Specifically, the detailed structural diagram and principle of the upper connector 1 are as follows: Figure 1 and Figure 12 As shown in (a), the lower end of the upper connector 1 is connected to the upper end of the tapered slip cylinder 2 of the first-stage adaptive slip module A by a thread. The inner diameter of the lower end of the upper connector 1 is smaller than the inner diameter of the slip steel ring 3, which is used to constrain the slip steel ring 3 and the tapered slip 6. The upper end of the upper connector 1 is used to connect the fishing string that is lowered into the well, so that they are connected as one unit.

[0163] Example 13

[0164] This utility model relates to a two-stage slip-type well-dumping screw pump rotor retrieval tool, the structure of which is as follows: Figure 1 As shown, the main body is a cylindrical structure, including an upper connector 1. The upper connector 1 is connected to a primary adaptive slip module A. The primary adaptive slip module A is connected to a secondary hinge slip module B. The secondary hinge slip module B is connected to a guide shoe 11.

[0165] The first-level adaptive slip module A includes a conical slip cylinder 2, inside which a slip steel ring 3 is provided. Multiple conical slips 6 are evenly arranged on the slip steel ring 3. The outer wall of each conical slip 6 is tightly attached to the inner wall of the conical slip cylinder 2. The inner diameter of the lower end of the upper connector 1 is smaller than the inner diameter of the slip steel ring 3. Each conical slip 6 has a constraint cavity 6-2, and a constraint block 5 is installed in each constraint cavity 6-2. The upper end of the conical slip cylinder 2 is threadedly connected to the lower end of the upper connector 1. The inner diameter of the lower end of the upper connector 1 is smaller than the inner diameter of the slip steel ring 3. The lower end of the conical slip cylinder 2 is threadedly connected to the upper end of the second-level hinged slip module B.

[0166] The inner wall of the conical slip cylinder 2 is designed as an inverted conical surface, and its inner diameter gradually shrinks from the top to the bottom. The conical slip 6 moves up and down along the inner wall of the conical slip cylinder 2 under the action of the lower screw pump rotor 12.

[0167] The upper part of the conical slip 6 is provided with a steel ring groove 6-1. The cross-section of the steel ring groove 6-1 is T-shaped. The conical slip 6 is embedded in the slip steel ring 3 through the steel ring groove 6-1. A screw hole 6-3 is provided below the steel ring groove 6-1. The screw hole 6-3 is arranged longitudinally. The constraint cavity 6-2 is provided outside the screw hole 6-3. The lower end of the conical slip 6 has a slip circular inclined surface 6-4 on the outside and a first arc surface sawtooth slip tooth 6-5 inside. The lower end of the conical slip 6 has a first rounded corner transition surface 6-6 on the inner side.

[0168] Multiple conical slips 6, under the thrust of the lower screw pump rotor 12, move upward along the inner wall of the conical slip cylinder 2 and open radially along the slip steel ring 3, encircling the screw pump rotor 12. Under the action of the gravity of the conical slip system and the lifting force of the tubing string, the multiple conical slips 6 slide downward and circumferentially lock the screw pump rotor 12. When the secondary slip type well-drop screw pump rotor retrieval tool is lifted, the multiple conical slips 6 retract radially along the slip steel ring 3, so that their slip teeth tightly lock the screw pump rotor 12. That is, the first-stage adaptive slip module A plays a role, and successful retrieval can be achieved.

[0169] When the tool is lowered to the rotor position and an upward pulling force is applied, the conical slip 6 moves upward along the inner wall of the conical slip cylinder 2 under the action of axial force. Due to the conical fit, radial contraction occurs, which automatically clamps the outer surface of the screw pump rotor 12.

[0170] The action of the conical slip 6 relies on the axial tension of the retrieval tool and the gravity during descent. It automatically contracts and tightens when lifted and releases when lowered, requiring no additional hydraulic or mechanical drive devices. It has a simple structure and high reliability, making it particularly suitable for complex downhole environments such as high temperature, high pressure, and sand-containing well fluids, reducing the probability of retrieval failure due to mechanical failure.

[0171] The structure of constraint block 5 matches the structure of constraint cavity 6-2. The upper and lower end faces of constraint block 5 are respectively attached to the upper and lower end faces of constraint cavity 6-2. A screw through hole 5-3 is opened in the middle of constraint block 5 at the position corresponding to screw hole 6-3. Screw 4 passes through screw hole 6-3 and screw through hole 5-3 in sequence.

[0172] The secondary hinge-type slip module B includes a hinge slip cylinder 7. The upper end of the hinge slip cylinder 7 is threadedly connected to the lower end of the primary adaptive slip module A, and the lower end of the hinge slip cylinder 7 is threadedly connected to the guide shoe 11. Multiple window slots 7-1 are evenly arranged in the middle of the hinge slip cylinder 7. Each window slot 7-1 is provided with a hinge slip 10. Each hinge slip 10 is connected to the cylinder wall of the hinge slip cylinder 7 through a circular ring 9. Each hinge slip 10 has a cutting groove 10-5 at its outer end. The circular ring 9 passes through each cutting groove 10-5, and a torsion spring 8 is sleeved on the part of the circular ring located in the cutting groove 10-5.

[0173] The outer end of the hinge slip 10 is a semi-cylindrical structure, and the middle of the outer end is provided with a hinge through hole 10-3. The inner end of the hinge slip 10 is provided with a second arc-shaped sawtooth slip tooth 10-2. The second arc-shaped sawtooth slip tooth 10-2 gradually converges from the lower end to the upper end along the central axis of the hinge slip cylinder 7.

[0174] After being locked, the hinge slip 10 fits tightly against the surface of the screw pump rotor 12, providing a strong gripping force. Its second arc-shaped sawtooth slip teeth 10-2 are designed to embed into the surface of the screw pump rotor 12, increasing friction and preventing the screw pump rotor 12 from slipping during retrieval. Furthermore, when multiple hinge slips 10 are used together, they can clamp the screw pump rotor 12 from different angles, further improving the gripping strength and stability.

[0175] The hinge and slip 10 have a relatively simple structure and are not prone to serious damage under normal use. Even if some parts are damaged, they can be repaired by replacing the hinges, slip teeth, and other parts, resulting in low maintenance costs. They can be reused multiple times, reducing the cost of salvage operations.

[0176] The hinge slip 10 can be adjusted according to the size and shape of the screw pump rotor 12 after it has been lowered into the well. For rotors that have undergone slight deformation after being lowered into the well, the hinge slip can adapt to the changes in shape by opening and closing and adjusting itself, ensuring a certain gripping effect. Compared with integral slips, it is more adaptable to different working conditions.

[0177] The hinge slip cylinder 7 has a boss 7-2 and a protective shell located in the middle outside the window groove 7-1.

[0178] The torsion spring 8 has two ends at 90°. One end of the torsion spring 8 is inserted into a small horizontal hole in the cutting groove 10-5, and the other end is fixed and constrained by the boss 7-2 of the hinge slip cylinder 7 and the protective shell. Under the upward force of the screw pump rotor 12, the six hinge slips 10 in the naturally closed state are opened. At the same time, the six torsion springs 8 are compressed. The torsion springs 8 rebound and act on the six hinge slips 10, making the six hinge slips 10 tend to close. The secondary slip type screw pump rotor retrieval tool is lifted, so that the second arc surface sawtooth slip teeth 10-2 tightly bite the screw pump rotor 12. That is, the secondary hinge type slip module B plays a role, and successful retrieval can be achieved.

[0179] The working process of this utility model of a two-stage slip-type well-dumping screw pump rotor retrieval tool is as follows:

[0180] In the first-stage adaptive slip module A, multiple adaptive conical slips 6 move upward along the inner conical surface of the conical slip cylinder 2 under the jacking force of the lower screw pump rotor 12, and open radially along the slip steel ring 3. Under the action of the gravity of the conical slips 6 and the lifting force of the retrieval string, the multiple conical slips 6 radially converge and lock the screw pump rotor 12. In the second-stage hinge slip module B, multiple hinge slips 10 open under the jacking force of the lower screw pump rotor 12, overcoming the elastic force of the corresponding multiple torsion springs 8. The arc-shaped sawtooth slip teeth of the hinge slips 10 contact the screw pump rotor 12 with the maximum area. The retrieval tool of the screw pump rotor is lifted, so that the arc-shaped sawtooth slip teeth of the hinge slips 10 tightly bite the screw pump rotor 12 circumferentially, achieving successful retrieval.

[0181] The advantages of this utility model of a two-stage slip-type well-dumping screw pump rotor retrieval tool are:

[0182] The first-level adaptive slip module A, under the action of the thrust of the lower screw pump rotor, can move up along the inner conical surface of the conical slip cylinder and open radially along the slip steel ring. Under the action of the gravity of the conical slip and the lifting force of the tubing, the multiple conical slips circumferentially lock the screw pump rotor.

[0183] The secondary hinge-type slip module B has multiple hinge slips that can open under the jacking force of the lower screw pump rotor, overcoming the elastic force of the torsion spring. The arc-shaped sawtooth slip teeth of the hinge slips contact the screw pump rotor with the maximum area. When the secondary slip-type well-dumping screw pump rotor retrieval tool is lifted, the second arc-shaped sawtooth slip teeth tightly bite the screw pump rotor along the circumference of the screw pump rotor.

[0184] By using different types of primary adaptive slip modules A, secondary hinge slip modules B, and guide shoes 11, the smooth screw pump rotor 12 can be locked in multiple directions and in all directions, enabling successful retrieval in one go; the integrated structure is simple, can be used multiple times in the well, only the slip tooth parts need to be replaced, it has a long service life, and is safe and efficient.

[0185] Unless otherwise defined, the technical or scientific terms used in this application shall have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The use of terms such as "a," "an," or "the" in the patent application specification and claims does not indicate a quantity limitation, but rather indicates the presence of at least one. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the element or object listed following the word and its equivalents. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; these relative positional relationships may change accordingly when the absolute position of the described object changes.

[0186] Although this application has been described with reference to the foregoing embodiments, those skilled in the art will understand that various changes can be made without departing from the spirit and scope of this application as defined by the appended claims. While this specification contains details of many specific implementations, these should not be construed as limiting the scope of the claims, but rather as descriptions of features specific to particular embodiments. The scope of this application is defined by the appended claims and their equivalents, and is not limited to the embodiments described above.

[0187] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0188] Finally, it should be noted that the above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. 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 two-stage slip-type well-dumping screw pump rotor retrieval tool, characterized in that, It includes an upper connector (1), which is connected to a primary adaptive slip module A, which is connected to a secondary hinge slip module B, and the secondary hinge slip module B is connected to a guide shoe (11).

2. The two-stage slip-type well-dumping screw pump rotor retrieval tool according to claim 1, characterized in that, The first-level adaptive slip module A includes a conical slip cylinder (2), a slip steel ring (3) is provided inside the conical slip cylinder (2), and multiple conical slips (6) are evenly arranged on the slip steel ring (3). The outer wall of each conical slip (6) is tightly attached to the inner wall of the conical slip cylinder (2), and the inner diameter of the lower end of the upper connector (1) is smaller than the inner diameter of the slip steel ring (3). Each conical slip (6) has a constraint cavity (6-2), and a constraint block (5) is installed in each constraint cavity (6-2). The upper end of the conical slip cylinder (2) is threadedly connected to the lower end of the upper connector (1), and the inner diameter of the lower end of the upper connector (1) is smaller than the inner diameter of the slip steel ring (3). The lower end of the conical slip cylinder (2) is threadedly connected to the upper end of the second-level hinged slip module B.

3. The two-stage slip-type well-dumping screw pump rotor retrieval tool according to claim 2, characterized in that, The slip steel ring (3) includes a steel ring (3-2), on which a plurality of partition protrusions (3-1) are evenly provided. The number of partition protrusions (3-1) corresponds to the number of conical slips (6), and the plurality of conical slips (6) are evenly separated by partition protrusions (3-1).

4. The two-stage slip-type well-dumping screw pump rotor retrieval tool according to claim 3, characterized in that, The dividing boss (3-1) consists of an upper dividing boss and a lower dividing boss, and is symmetrically distributed on the upper and lower end faces of the steel ring (3-2); The steel ring (3-2) is a square steel ring.

5. The two-stage slip-type well-dumping screw pump rotor retrieval tool according to claim 2, characterized in that, The upper part of the conical slip (6) is provided with a steel ring groove (6-1). The cross section of the steel ring groove (6-1) is T-shaped. The conical slip (6) is embedded in the slip steel ring (3) through the steel ring groove (6-1). A screw hole (6-3) is provided below the steel ring groove (6-1). The screw hole (6-3) is arranged longitudinally. The constraint cavity (6-2) is located outside the screw hole (6-3). The lower end of the conical slip (6) has a slip circular inclined surface (6-4) on the outside. The inside is provided with a first arc surface sawtooth slip tooth (6-5). The lower end of the conical slip (6) is provided with a first rounded corner transition surface (6-6).

6. The two-stage slip-type well-dumping screw pump rotor retrieval tool according to claim 5, characterized in that, The structure of the constraint block (5) matches the structure of the constraint cavity (6-2). The upper and lower end faces of the constraint block (5) are respectively attached to the upper and lower end faces of the constraint cavity (6-2). A screw through hole (5-3) is provided in the middle of the constraint block (5) at the position corresponding to the screw hole (6-3). The screw (4) passes through the screw hole (6-3) and the screw through hole (5-3) in sequence.

7. The two-stage slip-type well-dumping screw pump rotor retrieval tool according to claim 2, characterized in that, The inner wall of the conical slip cylinder (2) is set as an inverted conical surface structure, and its inner diameter gradually shrinks from the upper end to the lower end. The conical slip (6) moves up and down along the inner wall of the conical slip cylinder (2) under the action of the lower screw pump rotor (12).

8. The two-stage slip-type well-dumping screw pump rotor retrieval tool according to claim 1, characterized in that, The secondary hinge-type slip module B includes a hinge slip cylinder (7). The upper end of the hinge slip cylinder (7) is threadedly connected to the lower end of the primary adaptive slip module A. The lower end of the hinge slip cylinder (7) is threadedly connected to the guide shoe (11). Multiple window slots (7-1) are evenly arranged in the middle of the hinge slip cylinder (7). Each window slot (7-1) is provided with a hinge slip (10). Each hinge slip (10) is connected to the cylinder wall of the hinge slip cylinder (7) through a ring (9). A cutting groove (10-5) is opened at the outer end of each hinge slip (10). The ring (9) passes through each cutting groove (10-5), and a torsion spring (8) is sleeved on the part of the ring located in the cutting groove (10-5).

9. The two-stage slip-type well-dumping screw pump rotor retrieval tool according to claim 8, characterized in that, The outer end of the hinge slip (10) is a semi-cylindrical structure, and a hinge through hole (10-3) is provided in the middle of the outer end. The inner end of the hinge slip (10) is provided with a second arc-shaped sawtooth slip tooth (10-2). The second arc-shaped sawtooth slip tooth (10-2) gradually converges from the lower end to the upper end along the central axis of the hinge slip cylinder (7). The hinge slip cylinder (7) has a boss (7-2) and a protective shell located on the outside of the window groove (7-1) in the middle. The two ends of the torsion spring (8) are at 90°. One end of the torsion spring (8) is inserted into a horizontal small hole in the cutting groove (10-5), and the other end is fixed and constrained by the boss (7-2) and the protective shell of the hinge slip cylinder (7).

10. The two-stage slip-type well-dumping screw pump rotor retrieval tool according to claim 9, characterized in that, The inner end of the hinge slip (10) is provided with a second rounded transition surface (10-1) at both the upper and lower ends of the second arc-shaped sawtooth slip tooth (10-2). Each of the window slots (7-1) has a through hole (7-3) on its side wall along the circumference of the hinge slip cylinder (7) for the circular ring (9) to pass through. The lower inner side of the hinge slip cylinder (7) has a transition flared opening (7-4).

11. The two-stage slip-type well-dumping screw pump rotor retrieval tool according to claim 1, characterized in that, The lower end of the guide shoe (11) is provided with a vertical guide surface (11-2) and a spiral guide surface (11-3), with one end of the spiral guide surface (11-3) located at the lower end of the vertical guide surface (11-2).

Images