Fish salvaging device for special-size wellbore
By designing a fish-falling salvage device for special-size wellbores, the design of bent joints and regularizers is used to solve the problem of poor salvage effect in the prior art, efficient fish-falling salvage is achieved, and accident handling time and economic losses are reduced.
Patent Information
- Application Number
- CN202421971378.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-15
- Publication Date
- 2025-05-16
- Estimated Expiration
- 2034-08-15
AI Technical Summary
In special-size wellbores, existing salvage tools are difficult to effectively fit and salvage and fall off the fish, resulting in poor salvage effect and increasing accident handling time and economic losses.
A fish-fall salvage device including a salvage tool, a first drill collar, a bent joint, a second drill collar, a straightener and a drill rod is designed. Through the eccentric angle of the bent joint and the design of the straightener, it ensures that the salvage tool can be stably inserted and effectively salvage the fallen fish.
The device can be successfully inserted and salvaged and dropped fish in special-size wellbores, shortening the accident handling cycle, avoiding the scrapping of the wellbore and reducing the economic losses caused by filling side drilling.
Smart Images
Figure CN222879656U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of oil and natural gas drilling, and in particular relates to a device which can fish out fish dropped by drilling tools in a wellbore of special size. Background Art
[0002] As the exploration of oil and gas resources gradually develops deeper into the formation, deep wells and ultra-deep wells are gradually increasing, and the depth of the wellbore structure of the upper large-size wellbore (greater than φ241mm) is gradually extended. Due to the loose lithology, poor cementation, and good permeability of the formation in this section of the well, the well wall is unstable and collapsed; and due to the leakage of the drilling tool, short-circuit circulation occurs, and the drilling fluid pierces the well wall through the leakage point, resulting in irregular wellbore and enlarged wellbore diameter (the actual wellbore diameter is greater than the drill bit diameter by 20% or more), that is, a special size wellbore. When a drilling tool accident occurs in such a wellbore, in order to reduce losses, it is necessary to implement salvage operations to salvage as many fish as possible.
[0003] Fish fall refers to the drill pipe, drill collar, drill bit, oil pipe, sucker rod, salvage tools and instruments that fall into the well due to various reasons (such as accidents, equipment failures, etc.). The top of the fish fall is called the fish head, the bottom of the fish fall is called the fish tail, and the length of the fish fall is called the fish length.
[0004] In the prior art, the conventional processing methods have the following problems:
[0005] 1. Due to the large annular gap between the fish head and the special-sized wellbore and the fish not being centered, the existing fishing tools can find the fish head position, but cannot effectively lead the fish into the fishing tools. The fishing tools will step over the fish head as they are lowered. In addition, the wellbore wall is scourred and scraped by the long-term pumping and rotary fishing, causing the wellbore size at the fish head to further expand, and even causing the fish head to lean against the side and be squeezed into the well wall, resulting in the collapse of the well wall, resulting in falling blocks or sand settling to bury the fish and jam the drill.
[0006] 2. Salvage drill assembly with bent drill pipe: Due to its insufficient rigidity, the salvage drill assembly is too flexible. When the fish head is pushed, the drill tool on the bent drill pipe receives the opposite force, pushing it against the well wall in the opposite direction, causing the salvage tool to move in the opposite direction. As a result, the salvage tool can occasionally find the fish head, but it easily goes over the fish head when it is pushed, and cannot enter (slip into) the fish head, resulting in salvage failure;
[0007] 3. Snap-on drill bit assembly with bent joint: Compared with bent drill pipe, bent joint can make the lower drill bit or tool deviate to a certain extent at the same well depth and in different directions. It has the characteristics of high strength and high rigidity, relatively fixed angle and little influence by external conditions. However, due to the large gap between the upper drill bit in the casing and the casing annulus, and unable to provide effective support for the lower salvage drill bit, even if it can touch the fish head, it is difficult to keep the lower salvage tool continuously facing the specified direction because the drill bit with a large gap with the upper annulus absorbs the reverse torque caused by the elastic load of the bent joint, thus causing the fish head to be stepped over, resulting in salvage failure.
[0008] In summary, the treatment methods in the prior art have poor effects, increase the number of trips and drills and the time it takes for the fish to remain stationary, miss the best time to salvage, increase the difficulty of treatment, and even cause the wellbore to be scrapped due to treatment failure and side drilling. Utility Model Content
[0009] Based on the above technical background, the utility model provides a fish salvage device for a wellbore of special size, which can not only effectively enable the salvage tool to smoothly insert the fish in the wellbore of special size, but also effectively salvage the fish, shortening the accident handling cycle, thereby avoiding the problem of poor salvage effect in the prior art and long accident handling time, resulting in wellbore scrapping, and effectively reducing the economic losses caused by well filling and side drilling.
[0010] In order to achieve the above-mentioned invention object, the technical solution of the utility model is as follows:
[0011] A fish salvage device for a wellbore of a special size comprises a salvage tool, a first drill collar, a bent joint, a second drill collar, a stabilizer and a drill pipe, wherein the salvage tool, the first drill collar, the bent joint, the second drill collar, the stabilizer and the drill pipe are connected end to end in sequence, the maximum outer diameter of the salvage tool is 10 mm or more smaller than the size of the drill bit used, the outer diameter of the first drill collar is 10 mm or more smaller than the size of the drill bit used, the outer diameter of the bent joint is the same as the outer diameter of the first drill collar, the outer diameter of the second drill collar is less than or equal to the outer diameter of the first drill collar, the weight of the second drill collar is greater than the pressurized weight required for salvaging the fish, and the outer diameter of the stabilizer is 10-15 mm smaller than the maximum outer diameter of the salvage tool.
[0012] The salvaging tool is a female cone for salvaging the outside of the fish head, and the female cone is connected to the first drill collar through a double-hook safety joint.
[0013] The salvaging tool is a slip salvage tube for salvaging the outside of the fish head.
[0014] The salvaging tool is a male cone for salvaging the water eye of the fish head, and the male cone is connected to the first drill collar through a double-hook safety joint.
[0015] A drilling tool check valve is arranged on the upper part of the fishing tool, and the drilling tool check valve serves as an internal blowout prevention tool when there is a gas measurement display.
[0016] The eccentric angle of the bent joint is 1.5°, 2°, 2.5° or 2.75°, so as to generate a stable offset when salvaging fallen fish.
[0017] A drilling jar is arranged between the bent joint and the connection point of the second drill collar. If the fish is caught and stuck, the jar can be activated to jar and release the stuck fish.
[0018] A drill rod is arranged between the second drill collar and the lower part of the centralizer, so that the centralizer is located inside the casing, which reduces the lateral force generated by itself during the salvage process and prevents the casing shoe from being damaged and deformed.
[0019] The length between the centralizer and the fishing tool is greater than the length of the casing in the wellbore. Before the centralizer is connected, the fishing tool must be out of the casing and into the open hole.
[0020] The component connections of the fish salvaging device are provided with variable buckle joints, and components with matching buckle types are selected as much as possible to reduce the access of variable buckle joints and avoid increasing the weak points of the entire salvaging combination.
[0021] A guide shoe is arranged outside the fishing tool, and the size of the guide shoe is smaller than the size of the drill bit used by 10 mm or more.
[0022] Beneficial effects of the utility model:
[0023] 1. The utility model can not only effectively enable the salvage tool to smoothly insert the fish in the wellbore of special size, but also effectively salvage the fish, shortening the accident handling cycle, thereby avoiding the problem of poor salvage effect and long accident handling time in the prior art, resulting in the wellbore being scrapped, and effectively reducing the economic losses caused by well filling and side drilling.
[0024] 2. In the utility model, a directional drilling tool is introduced into the salvage operation of fish in the well. With the help of the offset of the bent joint, the salvage tool can be directed to the specified tool surface. Compared with the bent drill pipe, it has the characteristics of high strength and high rigidity, fixed angle, and little influence by external conditions. It effectively solves the problem that the head of the fish is in a wellbore of special size and is difficult to capture.
[0025] 3. In the utility model, a centralizer is added to the salvage drill tool assembly to increase the rigidity of the salvage drill tool, reduce the lateral force generated by the salvage drill tool itself during the salvage process, provide effective centralizing and supporting effects for the lower salvage drill tool, and effectively solve the problem that the reverse torque caused by the elastic load of the bent joint absorbed by the drill tool with a large upper annular space gap, so it is particularly difficult to keep the lower salvage tool continuously facing the specified direction, thereby causing the fish head to be stepped over and causing the salvage failure. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Figure 1 The utility model is a schematic structural diagram of a fish salvaging device for a wellbore of a special size.
[0027] Among them, 1. salvage tools; 2. first drill collar; 3. bent joint; 4. second drill collar; 5. stabilizer; 6. drill pipe. DETAILED DESCRIPTION
[0028] The present invention is further described in detail below in conjunction with the embodiments, but the implementation manner of the present invention is not limited thereto.
[0029] Example 1
[0030] This embodiment provides a Figure 1 The fish salvage device for a wellbore of a special size shown in the figure comprises a salvage tool 1, a first drill collar 2, a bent joint 3, a second drill collar 4, a centralizer 5 and a drill pipe 6, wherein the salvage tool 1, the first drill collar 2, the bent joint 3, the second drill collar 4, the centralizer 5 and the drill pipe 6 are connected end to end in sequence, the maximum outer diameter of the salvage tool 1 is 10 mm or more smaller than the drill bit size used in the current open hole section of the wellbore, the outer diameter of the first drill collar 2 is 10 mm or more smaller than the drill bit size used in the current open hole section of the wellbore, and the outer diameter of the bent joint 3 is the same as the outer diameter of the first drill collar 2 The outer diameter of the second drill collar 4 is less than or equal to the outer diameter of the first drill collar 2, the weight of the second drill collar 4 is greater than the pressurized weight required for salvaging fallen fish, the outer diameter of the stabilizer 5 is 10-15mm smaller than the maximum outer diameter of the salvaging tool 1, the salvaging tool 1 is a female cone outside the fish head for salvaging fallen fish, and the female cone is connected to the first drill collar 2 through a double-clasp safety joint; the eccentric angle of the bent joint 3 is 1.5°; the length between the stabilizer 5 and the salvaging tool 1 is greater than the length of the casing in the wellbore, and a variable buckle joint is provided at the connection between the components of the fish salvaging device.
[0031] In this embodiment, the fish is salvaged through the following steps:
[0032] S1: Assemble the fish salvage device for special-sized wells on site, select the appropriate salvage tool 1 according to the size of the fish head and the drill bit used in the current open hole section of the well, and the maximum outer diameter of the salvage tool 1 is 10 mm or more smaller than the drill bit size used in the current open hole section of the well; select the elbow 3 as needed, and the specification of the elbow 3 is preferably 1.5° to meet the requirement of generating a stable offset when salvaging the fish; the specification of the second drill collar 4 is not larger than the first drill collar 2, and its weight should be larger than the pressurized weight required by the lower salvage tool 1 when salvaging the fish; the maximum outer diameter of the stabilizer 5 is 10-15 mm smaller than the maximum outer diameter of the salvage tool 1, which increases the rigidity of the salvage drill bit and provides effective straightening and support for the lower salvage drill bit; before connecting the stabilizer 5, the salvage tool 1 must be out of the casing shoe and have entered the open hole; between the connections of the above components, add variable buckle joints as needed, and select components with matching buckle types as much as possible to reduce the connection of variable buckle joints and avoid increasing the weak points of the entire salvage combination;
[0033] S2: Lower the assembled special-sized wellbore fish salvage device assembly into the well: Lower the assembled special-sized wellbore salvage drill assembly into the well, calculate the theoretical well depth of the fish top, and lower the special-sized wellbore salvage drill assembly into the well 5m away from the fish top;
[0034] S3: Pump on: The pump displacement is 1 / 4 to 1 / 3 of the drilling displacement of the drill bit in the current open hole section of the wellbore;
[0035] S4: Probing the fish head: the probing depth shall not exceed 1m of the theoretical fish head; if the fish head is not found and the vertical pressure does not rise, lift the drill bit to a depth of 5m from the theoretical fish top, rotate the drill bit to change the direction and probe the fish head, rotating the drill bit 90° each time before probing the fish head;
[0036] S5: Operate the special-sized wellbore fish salvage device to salvage: after finding the head of the fish, rotate the drill bit and press down to make a buckle to salvage or press down to grab the fish; if the fish is stuck, start the jar to release the jam or move the drill bit up and down to release the jam, and gradually increase the circulating displacement to cooperate with the release;
[0037] S6: Lift out the special-sized wellbore salvage drill bit assembly and the fish: After catching the fish, lift out the special-sized wellbore salvage drill bit assembly and the fish from the well.
[0038] Example 2
[0039] Compared with Example 1, the present embodiment is different in that, in the present embodiment, the salvage tool 1 is a slip salvage tube for salvaging the outside of the fish head; a drill check valve is arranged on the upper part of the salvage tool 1; the eccentric angle of the elbow 3 is 2.75°; a drilling jar is arranged between the connection between the elbow 3 and the second drill collar 4, and the remaining structure is the same as that of Example 1.
[0040] In this embodiment, the salvage tool 1 is selected as a slip salvage tube for salvaging the outside of the fish head according to the type of fish; when gas measurement is detected in the wellbore, a drill bit check valve is set on the upper part of the salvage tool 1 as an internal blowout prevention tool; after the drilling jar catches the fish and the fish is stuck, the jar can be started to jar and release the jam.
[0041] Example 3
[0042] Compared with Example 1, the present embodiment is different in that, in the present embodiment, the salvage tool 1 is a male cone for salvaging the water eye of the fish head, and the male cone is connected to the first drill collar 2 through a double-snap safety joint; the eccentric angle of the bent joint 3 is 2.5°; a drill rod 6 is arranged above the second drill collar 4 and between the lower part of the stabilizer 5; and the remaining structure is the same as that of Example 1.
[0043] In this embodiment, since the buckle types of the components do not match, a variable buckle joint is provided at the connection between the components; a drill rod 6 is provided between the second drill collar 4 and the lower part of the stabilizer 5, so that the stabilizer 5 is located inside the casing, thereby reducing the lateral force generated by itself during the salvage process and preventing damage and deformation of the casing shoe.
[0044] Example 4
[0045] The difference between this embodiment and embodiment 1 is that, in this embodiment, a guide shoe is provided on the outside of the salvage tool 1, and the size of the guide shoe is 10 mm or more smaller than the drill bit size used in the current open hole section of the wellbore, and the rest of the structure is the same as that of embodiment 1.
[0046] In this embodiment, the salvage tool 1 is provided with a guide shoe to prevent the bottom of the salvage tool 1 from scraping or inserting into the well wall, thereby ensuring that the salvage tool 1 can be smoothly inserted into the fish head.
[0047] In this embodiment, when drilling to 222.4m using a φ660.4mm drill bit, a drill bit breakage failure occurred. The fish top was a φ139.7mm weighted drill pipe female thread (the outer diameter of the fish top was φ178mm). The electric well diameter measurement showed that the well depth at the fish top was 65.00m, the well diameter at the fish top was greater than 839mm, and the φ720.00mm casing was 44.00m deep.
[0048] The combination is used for the fishing drill bit assembly of special-sized wells, which are connected in sequence from bottom to top, namely, fishing tool 1 (φ650mm guide shoe + female cone Mz210 + φ203mm safety joint) + variable buckle joint + φ203mm drill collar 1 + φ203mm bent joint 3 (2°) + φ203mm drill collar 2 + variable buckle joint + φ640mm centralizer 5 + variable buckle joint + φ139.7mm drill pipe 6. φ640mm centralizer 5 position: 35m.
[0049] Drill down to a well depth of 60m, start the pump to explore the fish head with a displacement of 20L / s. When drilling down to 65m, the vertical pressure increases from 0.2Mpa to 2.4Mpa, and the fish top is found. The torque of the top drive device is limited to 10, 15, 20, 25, 30, and 32kN.m respectively, and the drill bit is repeatedly rotated to make a buckle and tightened for 3 circles; the drill bit is repeatedly moved up and down at a hanging weight of 380~860kN, and the displacement is gradually increased to circulate and clean the wellbore. The hanging weight increases from 380↑860↓780kN, the drill is pulled out, and the fallen fish is fished out.
[0050] It is understood that the present invention is described by some embodiments, and those skilled in the art are aware that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the scope of protection of the present invention.
Claims
1. A fish salvage device for special-sized wells, characterized in that: The invention comprises a salvaging tool (1), a first drill collar (2), a bent joint (3), a second drill collar (4), a centralizer (5) and a drill pipe (6), wherein the salvaging tool (1), the first drill collar (2), the bent joint (3), the second drill collar (4), the centralizer (5) and the drill pipe (6) are connected end to end in sequence, the maximum outer diameter of the salvaging tool (1) is smaller than the size of a drill bit used for drilling by 10 mm or more, the outer diameter of the first drill collar (2) is smaller than the size of a drill bit used for drilling by 10 mm or more, the outer diameter of the bent joint (3) is the same as the outer diameter of the first drill collar (2), the outer diameter of the second drill collar (4) is smaller than or equal to the outer diameter of the first drill collar (2), the weight of the second drill collar (4) is greater than the pressurized weight required for salvaging fallen fish, and the outer diameter of the centralizer (5) is smaller than the maximum outer diameter of the salvaging tool (1) by 10-15 mm.
2. The fish salvage device for special-sized wells according to claim 1, characterized in that: The salvaging tool (1) is a female cone for salvaging the outside of a fish head, and the female cone is connected to the first drill collar (2) via a double-hook safety joint.
3. The fish salvage device for special-sized wells according to claim 1, characterized in that: The salvaging tool (1) is a slip salvage tube for salvaging the outside of the fish head.
4. The fish salvage device for special-sized wells according to claim 1, characterized in that: The salvaging tool (1) is a male cone for salvaging the water eye of a fallen fish head, and the male cone is connected to the first drill collar (2) via a double-hook safety joint.
5. The fish salvaging device for special-sized wells according to any one of claims 2 to 4, characterized in that: A drilling tool check valve is provided on the upper part of the salvage tool (1).
6. The fish salvaging device for special-sized wells according to any one of claims 2 to 4, characterized in that: The eccentric angle of the bent joint (3) is 1.5°, 2°, 2.5° or 2.75°.
7. The fish salvage device for special-sized wells according to any one of claims 2 to 4, characterized in that: A drilling jar is provided between the connection between the bent joint (3) and the second drill collar (4).
8. The fish salvaging device for special-sized wells according to any one of claims 2 to 4, characterized in that: A drill rod (6) is arranged between the second drill collar (4) and the lower part of the centralizer (5).
9. The fish salvaging device for special-sized wells according to any one of claims 2 to 4, characterized in that: The length between the centralizer (5) and the fishing tool (1) is greater than the length of the casing in the wellbore.
10. The fish salvaging device for special-sized wells according to any one of claims 2 to 4, characterized in that: The fishing tool (1) is provided with a guide shoe on the outside, and the size of the guide shoe is smaller than the size of the drill bit used by 10 mm or more.