Screw motor rotor casing milling and fishing tool

Abstract

The utility model belongs to the field of oil and gas well drilling, and relates to a screw motor rotor casing milling and fishing tool. The tool aims to solve the problem that a fishing tool is difficult to clamp a fish due to damage of a fish head, so that the fishing success rate is increased, and drilling interruption and economic loss are avoided. According to the main scheme, the device comprises an upper connector and a cylinder assembly which are sequentially connected, a spiral slip and a control ring are arranged in the cylinder assembly, the cylinder assembly is connected with an auxiliary milling assembly, and the auxiliary milling assembly is connected with a guide shoe assembly. And the guide shoe assembly comprises a milling assembly, a guide shoe and a guide hook which are connected in sequence. According to the tool, through the design of the guide hook and the lengthened guide shoe and a double milling mechanism, the work of sleeving a falling fish and trimming a fish head is completed at a time, and the drilling construction efficiency and safety are improved. In addition, the fishing tool is also suitable for fishing other underground slender rod-shaped objects, and the universality of the tool is improved.

Description

Technical Field

[0001] The utility model belongs to the field of oil and gas well drilling, and relates to a fishing tool for underground accident handling, and is particularly suitable for a sleeve milling fishing tool for a screw motor rotor. The utility model is suitable for special fishing of slender rod-shaped objects underground, and specifically provides a sleeve milling fishing tool for a screw motor rotor. Background Art

[0002] In order to improve the drilling efficiency during the drilling process, screw motor bottom hole power tools are often used. The drilling tool is mainly composed of a stator housing, a rotor, a transmission shaft assembly, a universal shaft assembly, and a bypass valve assembly. During the drilling process, the screw motor rotor is prone to fall off the well and cause an accident in the well. If it cannot be salvaged from the well, drilling cannot be carried out, and even the wellbore is scrapped, resulting in huge economic losses.

[0003] In the conventional treatment of screw motor rotor falling into the well accident, a retractable overshot tube or a mother cone is mainly used for salvage, but these salvage methods still fail. Therefore, the field urgently needs to further improve the salvage tools. Utility Model Content

[0004] When dealing with the accident of the screw motor rotor falling into the well, the applicant also tried to use a retractable salvage tube and a mother cone for salvage, but all failed. After repeated experiments and research, it was found that the main reasons for the salvage failure were:

[0005] (1) Since the diameter of the screw motor is smaller than the diameter of the drill bit, and the diameter of the rotor is even smaller, once it falls into the well, the rotor leans against the well wall. Due to the size range of the salvaged objects, the conventional overshot tube and mother cone are easily misaligned with the fish head during drilling and salvage, resulting in salvage failure;

[0006] (2) In order to improve the success rate of conventional tools, some researchers added arc-shaped guide shoes or "bell-shaped" guide shoes to the front end of the salvage tool in an attempt to put the fish head into the salvage tool. However, in some mudstone or soft and broken formations, the rotor is embedded in the well wall after multiple treatments, making it difficult for such guide shoes to play an effective role and thus salvage fails.

[0007] (3) Since the fish salvage process often requires multiple drilling operations, the fish head is easily worn, damaged and deformed during the initial processing, making it difficult for subsequent salvage tools to fit into the fish head. Even if the fish head fits into the salvage tool, the surface of the fish head is damaged and the shape is irregular, making it difficult for the salvage tool to effectively clamp the fish head and complete the salvage work.

[0008] Therefore, the present invention has designed a special tool for motor rotor sleeve milling and salvaging based on many years of research and production experience in this field and repeated experiments, in order to solve the above-mentioned newly discovered problems.

[0009] The utility model makes full use of the guide hook and the extended guide shoe to avoid the dilemma of conventional salvage tools that the fish head cannot enter and cause salvage failure; at the same time, the salvage tool realizes double grinding and milling through the sleeve milling assembly and the auxiliary milling assembly set in the guide shoe assembly, which can fully trim the fish head and avoid the situation where the salvage tool is difficult to clamp the fallen fish due to damage to the fish head, resulting in salvage failure. In summary, through the above two technical means, the work of inserting the fallen fish and trimming the fish head can be achieved at one time, greatly improving the success rate of handling the accident of the screw motor rotor falling off. The tool is also suitable for the salvage of other slender rod-shaped objects underground.

[0010] The utility model aims to solve the problem that the salvage tool is difficult to clamp the fallen fish due to the damage of the fish head, thus resulting in salvage failure.

[0011] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0012] A screw motor rotor sleeve milling salvage tool comprises an upper joint and a barrel assembly which are connected in sequence, a spiral slip and a control ring are arranged in the barrel assembly, the barrel assembly is connected to an auxiliary milling assembly, and the auxiliary milling assembly is connected to a guide shoe assembly.

[0013] In the above technical solution, the guide shoe assembly includes a sleeve milling assembly, a guide shoe, and a guide hook which are connected in sequence.

[0014] In the above technical solution, the outer diameter of the guide shoe and the guide hook is 3 to 10 mm smaller than the outer diameter of the drill bit.

[0015] In the above technical solution, the sleeve milling assembly includes an upper end of the sleeve milling assembly, a middle inclined surface, and a lower end of the sleeve milling assembly, and the inner wall of the middle inclined surface is evenly distributed with the sleeve milling assembly alloy in the circumferential direction.

[0016] In the above technical solution, the outer diameter of the upper end of the sleeve milling assembly is consistent with the outer diameter of the auxiliary milling assembly, and the outer diameter of the lower end of the sleeve milling assembly is consistent with the outer diameter of the guide shoe.

[0017] In the above technical solution, the effective length L of the guide shoe is smaller than the length of the screw motor rotor by 0.5 to 1.0 m.

[0018] In the above technical solution, the auxiliary milling assembly includes a lower joint and an auxiliary milling ring fixed in the lower joint.

[0019] In the above technical solution, the auxiliary milling ring includes crushed alloy seats evenly distributed on the inner wall of the auxiliary milling ring, and auxiliary milling crushed alloy is arranged on the crushed alloy seats.

[0020] In the above technical solution, a positioning head is provided on the auxiliary milling ring, and the positioning head is clamped in the positioning groove of the lower joint, so as to ensure that the auxiliary milling ring and the lower joint are fixed in position, and prevent the auxiliary milling ring from rotating around the inner wall of the lower joint under external force, affecting the milling effect.

[0021] The utility model aims to solve the well accidents caused by the falling off of the screw motor rotor during oil and gas well drilling. The tool achieves its effect through the following technical means:

[0022] 1. Design of guide hook and extended guide shoe: The guide hook and extended guide shoe effectively avoid the problem of fish head being difficult to enter the salvage tool in conventional salvage tools, and improve the success rate of salvage. The guide hook mainly relies on the rotating tool to guide the small diameter screw motor rotor close to the well wall into the guide shoe. The outer diameter size D of the guide shoe and guide hook should be slightly smaller than the outer diameter of the drill bit by 3 to 10 mm to ensure that the guide hook can effectively guide the fallen fish; in addition, in order to avoid the situation of well depth error or inaccurate calculation of the fallen fish position, the effective length L of the guide shoe should be less than the length of the screw motor rotor by 0.5 to 1.0 m.

[0023] 2. Double milling mechanism: The sleeve milling assembly and the auxiliary milling assembly in the tool realize double milling of the fish head, fully trimming the fish head and solving the problem of difficulty in clamping the salvage tool due to damage to the fish head. The upper end of the sleeve milling assembly is threadedly connected to the auxiliary milling assembly, and the lower end is threadedly connected to the guide shoe; the outer diameter of the upper end is consistent with the outer diameter of the auxiliary milling assembly, and the outer diameter of the lower end is consistent with the outer diameter of the guide shoe. The middle inclined transition part is inlaid with crushed alloy. The main purpose is to perform preliminary milling of the fish head to avoid the irregular surface of the fish head that is difficult to enter the salvage tube. The auxiliary milling assembly mainly plays the role of further trimming the fish head. The middle is an auxiliary milling ring, and the auxiliary milling ring is a crushed alloy block, which is used to grind the fish head that enters the auxiliary milling assembly.

[0024] 3. Application of retractable overshot tube: Combined with the guide shoe assembly and the auxiliary milling assembly, the retractable overshot tube can effectively clamp the trimmed fish head and complete the salvage work. The retractable overshot tube is a conventional fish salvage tool. Through the guide shoe assembly and the auxiliary milling assembly, the fish leaning against the well wall is guided and the fish head is milled and trimmed twice, so that the outer diameter of the fish meets the salvage range of the retractable overshot tube. During the downward pressure process, the spiral slip is used to clamp the fish, and the fish is successfully salvaged by lifting it up.

[0025] Compared with the prior art, the advantages of the present invention are:

[0026] The success rate of handling screw motor rotor falling accidents is improved.

[0027] Reduce drilling interruptions and economic losses caused by salvage failures.

[0028] It is suitable for the salvage of other slender rod-shaped objects in the well, increasing the versatility of the tool.

[0029] Through these technical means, the utility model can complete the work of inserting the fish and trimming the fish head at one time, which greatly improves the efficiency and safety of drilling construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is the overall structure diagram of the utility model

[0031] Figure 2 It is a schematic diagram of the sleeve milling assembly;

[0032] Figure 3 , Figure 4 This is a schematic diagram of the auxiliary milling ring;

[0033] Description of reference numerals:

[0034] 1-upper joint, 2-sealing assembly, 3-cylinder assembly, 4-spiral slip, 5-control ring, 6-0-auxiliary milling ring, 6-1-crushed alloy seat, 6-2-auxiliary milling crushed alloy, 6-3-positioning head, 7-lower joint, 8-1-upper end of sleeve milling assembly, 8-2-middle bevel, 8-3-lower end of sleeve milling assembly, 8-4-sleeve milling crushed alloy, 9-guide shoe, 10-guide hook. DETAILED DESCRIPTION

[0035] The following is a detailed description of the embodiments of the present invention. Although the present invention will be described and illustrated in conjunction with some specific implementations, it should be noted that the present invention is not limited to these implementations. On the contrary, modifications or equivalent replacements made to the present invention should be included in the scope of the claims of the present invention.

[0036] In addition, in order to better illustrate the present invention, numerous specific details are given in the following specific embodiments. Those skilled in the art will understand that the present invention can also be implemented without these specific details.

[0037] The utility model is mainly divided into three parts, which are respectively a guide shoe assembly, an auxiliary milling assembly and a retractable overshot tube from bottom to top.

[0038] (1) Guide shoe assembly: It is mainly composed of a guide hook, a guide shoe, and a sleeve milling assembly. The guide shoe and guide hook are made by cutting a round tube, as shown in the figure below. The guide hook mainly relies on a rotating tool to guide the small-diameter screw motor rotor that is close to the well wall into the guide shoe. The outer diameter size D of the guide shoe and guide hook should be slightly smaller than the outer diameter of the drill bit by 3 to 10 mm to ensure that the guide hook can effectively guide the fish. In addition, in order to avoid the situation of errors in well depth or inaccurate calculation of the fish position, the effective length L of the guide shoe should be less than the length of the screw motor rotor by 0.5 to 1.0 m.

[0039] The upper end of the sleeve milling assembly is threadedly connected to the auxiliary milling assembly, and the lower end is threadedly connected to the guide shoe; the outer diameter of the upper end is consistent with the outer diameter of the auxiliary milling assembly, and the outer diameter of the lower end is consistent with the outer diameter of the guide shoe. The middle inclined transition part is inlaid with crushed alloy. The main purpose is to perform preliminary grinding and milling on the fish head to avoid the irregular surface of the fish head making it difficult to enter the salvage tube.

[0040] (2) Auxiliary milling assembly: The auxiliary milling assembly is mainly used to further trim the fish head. In the middle is the auxiliary milling ring, on which are broken alloy blocks, which are used to grind the fish head entering the auxiliary milling assembly.

[0041] (3) Retractable overshot:

[0042] It mainly includes an upper joint 1 and a barrel assembly 3. The barrel assembly 3 is provided with a spiral slip 4 and a control ring 5. The retractable salvage barrel is a conventional fish salvage tool. Through the guide shoe assembly and the auxiliary milling assembly, the fish leaning against the well wall is guided and the fish head is milled and trimmed twice to make the outer diameter of the fish meet the salvage range of the retractable salvage barrel. During the downward pressing process, the spiral slip is used to clamp the fish, and the fish is successfully salvaged by pulling up.

[0043] How to use the tool:

[0044] (1) Connect the guide shoe assembly to the auxiliary milling assembly on the surface, then connect it to the retractable overshot tube, and finally connect it to the drill string through the upper joint;

[0045] (2) Lower the tool to 3m above the fish head and start pumping the drilling fluid. Slowly rotate and lower the tool. Use the guide hook to straighten the fish and guide it into the guide shoe.

[0046] (3) Ensure that the fish head continues to rotate and initially grind the fish head after entering the guide shoe, slowly lower the rotary drill string, and then use the auxiliary milling assembly to further trim the fish head.

[0047] (4) After the fish head is trimmed, stop rotating, continue to lower the drill string, use the retractable salvage tube to clamp the fish head, lift the drill bit, and complete the fish salvage.

[0048] Embodiment 1:

[0049] In this embodiment, the screw motor rotor sleeve milling salvage tool includes an upper joint 1, a barrel assembly 3, a spiral slip 4, a control ring 5, an auxiliary milling assembly, and a guide shoe assembly. The guide shoe assembly includes a guide hook 10, a guide shoe 9, and a sleeve milling assembly 8. The outer diameter of the guide shoe and the guide hook is 3 to 10 mm smaller than the outer diameter of the drill bit. The sleeve milling assembly 8 includes an upper end 8-1 of the sleeve milling assembly, an intermediate bevel 8-2, and a lower end 8-3 of the sleeve milling assembly. The inner wall of the intermediate bevel 8-2 is evenly distributed with sleeve milling assembly broken alloy 8-4 on the circumference. The outer diameter of the upper end 8-1 of the sleeve milling assembly is consistent with the outer diameter of the auxiliary milling assembly, and the outer diameter of the lower end 8-3 of the sleeve milling assembly is consistent with the outer diameter of the guide shoe. The effective length L of the guide shoe 9 is less than the length of the screw motor rotor by 0.5 to 1.0 m. The auxiliary milling assembly includes a broken alloy seat 6-1 evenly distributed on the inner wall of the auxiliary milling ring 6-0, and an auxiliary milling broken alloy 6-2 is arranged on the broken alloy seat 6-1. In this embodiment, the above structural design can effectively improve the success rate of fish salvage, reduce accident time, and improve drilling construction efficiency.

[0050] The middle bevel 8-2 is an important part of the screw motor rotor sleeve milling salvage tool, which has the following effects and functions:

[0051] Transition function: The middle bevel serves as the transition area between the upper and lower parts of the tool, which can smoothly connect the upper and lower ends of the sleeve milling assembly to ensure the structural strength of the entire tool and the smoothness of operation.

[0052] Guiding function: The inclined design can help guide the screw motor rotor into the tool, ensuring that the rotor can be correctly positioned and fixed, creating conditions for subsequent salvage operations.

[0053] Finishing function: The middle slope is usually inlaid with crushed alloy or hard materials, which can perform preliminary grinding on the fish head of the screw motor rotor to remove surface damage or irregularities, making it easier to be captured and lifted by subsequent salvage mechanisms.

[0054] Increased contact area: The inclined design increases the contact area between the tool and the rotor fish head, which helps improve the tool's stability and fishing efficiency.

[0055] The main technical problem solved by the intermediate bevel is the irregular shape and damage of the rotor fish head. During the drilling process of oil and gas wells, the screw motor rotor may be damaged or deformed due to falling or other reasons. This damage and deformation can make it difficult for traditional fishing tools to effectively grasp and lift the rotor. The design of the intermediate bevel ensures that even irregular fish heads can be effectively fished by pre-trimming the fish head, thereby improving the success rate of fishing and reducing operation time.

[0056] Embodiment 2:

[0057] On the basis of Example 1, in this example, the outer diameter of the guide shoe and the guide hook is adjusted to be 5 mm smaller than the outer diameter of the drill bit (see what is the optimal value). By reducing the outer diameter of the guide shoe and the guide hook, the effect of the guide hook guiding the fallen fish into the guide shoe can be further improved, thereby improving the success rate of salvaging.

[0058] Embodiment 3:

[0059] On the basis of Example 1, in this example, the auxiliary milling alloy 6-2 in the auxiliary milling assembly is replaced with diamond fragments. The diamond fragments have a higher hardness and can further improve the milling effect on the fish head, thereby increasing the success rate of salvaging.

[0060] Embodiment 4:

[0061] Based on Example 1, in this example, the milling assembly alloy 8-4 uniformly distributed on the inner wall of the middle inclined surface 8-2 of the milling assembly 8 is replaced with tungsten steel fragments. The tungsten steel fragments have good wear resistance and can increase the service life of the milling assembly, thereby reducing maintenance costs.

[0062] Embodiment 5:

[0063] On the basis of Example 1, in this example, the effective length L of the guide shoe 9 is adjusted to be less than 0.8 m of the screw motor rotor length (see what is the optimal value). By adjusting the effective length of the guide shoe, the guiding effect of the guide shoe on the fallen fish can be further improved, thereby improving the success rate of salvaging.

[0064] Embodiment 6:

[0065] On the basis of Example 1, in this embodiment, the auxiliary milling assembly includes a lower joint and an auxiliary milling ring fixed in the lower joint. The auxiliary milling ring includes a crushed alloy seat evenly distributed on the inner wall of the auxiliary milling ring, and auxiliary milling crushed alloy is arranged on the crushed alloy seat. A positioning head is arranged on the auxiliary milling ring, and the positioning head is clamped in the positioning groove of the lower joint, so that the auxiliary milling ring and the lower joint can be fixed in position, and the auxiliary milling ring can be prevented from rotating around the inner wall of the lower joint under external force, which affects the milling effect.

[0066] In summary, the present invention can effectively improve the success rate of fish salvage, reduce accident time, and improve drilling construction efficiency through the above multiple embodiments. Different embodiments can be selected and adjusted according to actual needs to achieve the best salvage effect.

Claims

1. A screw motor rotor sleeve milling fishing tool, comprising an upper joint (1) and a barrel assembly (3) connected in sequence, wherein a spiral slip (4) and a control ring (5) are arranged in the barrel assembly (3), characterized in that: The cylinder assembly (3) is connected with an auxiliary milling assembly, and the auxiliary milling assembly is connected with a guide shoe assembly.

2. A screw motor rotor sleeve milling and salvaging tool according to claim 1, characterized in that: The guide shoe assembly comprises a sleeve milling assembly (8), a guide shoe (9) and a guide hook (10) which are connected in sequence.

3. The screw motor rotor sleeve milling and salvaging tool according to claim 1, characterized in that: The outer diameter of the guide shoe and the guide hook is 3 to 10 mm smaller than the outer diameter of the drill bit.

4. A screw motor rotor sleeve milling and salvaging tool according to claim 2, characterized in that: The sleeve milling assembly (8) comprises a sleeve milling assembly upper end (8-1), a middle inclined surface (8-2), and a sleeve milling assembly lower end (8-3) which are sequentially connected and arranged, and the sleeve milling assembly crushed alloy (8-4) is evenly distributed on the inner wall of the middle inclined surface (8-2) in the circumferential direction.

5. A screw motor rotor sleeve milling and salvaging tool according to claim 4, characterized in that: The outer diameter of the upper end (8-1) of the sleeve milling assembly is consistent with the outer diameter of the auxiliary milling assembly, and the outer diameter of the lower end (8-3) of the sleeve milling assembly is consistent with the outer diameter of the guide shoe.

6. A screw motor rotor sleeve milling and salvaging tool according to claim 2, characterized in that: The effective length L of the guide shoe (9) is 0.5 to 1.0 m less than the length of the screw motor rotor.

7. A screw motor rotor sleeve milling and salvaging tool according to claim 1, characterized in that: The auxiliary milling assembly comprises a lower joint (7) and an auxiliary milling ring (6-0) which is clamped and fixed in the lower joint (7).

8. The screw motor rotor sleeve milling and salvaging tool according to claim 7, characterized in that: The auxiliary milling ring (6-0) comprises crushed alloy seats (6-1) uniformly distributed on the inner wall of the auxiliary milling ring (6-0), and auxiliary milling crushed alloy (6-2) is arranged on the crushed alloy seat (6-1).

9. A screw motor rotor sleeve milling and salvaging tool according to claim 8, characterized in that: The auxiliary milling ring (6-0) is provided with a positioning head (6-3), and the positioning head (6-3) is clamped in the positioning groove of the lower joint (7).

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