Variable double-channel circulating valve

Abstract

The utility model relates to the technical field of oil and gas field well completion tools, in particular to a variable double-channel circulating valve which comprises an upper connector, an outer cylinder, a spacer bush, a ball seat, a piston, an inner sleeve, a lower connector, a shear pin, a channel I, a channel II and a channel III. The utility model relates to a variable double-channel circulating valve, which can effectively solve the problem of internal and external pressure difference balance during continuous oil pipe operation in a high-pressure well and avoid oil pipe damage caused by overlarge pressure difference. Meanwhile, after the oil pipe is tripped in place, the circulating valve can effectively close an inner channel and an outer channel, smooth pressure transmission of the upper channel and the lower channel is guaranteed, and specific operation requirements are met. In addition, in some conventional oil wells, especially in occasions where a packer at the lower end of a special pipe column is completely closed but forward and reverse circulation well washing operation needs to be carried out, after well washing is completed, a circulation channel can be closed, and the pressure transmission function of an upper channel and a lower channel can be maintained so as to set the packer.

Description

Technical Field

[0001] The utility model relates to the technical field of oil and gas well completion tools, and particularly relates to a variable double-channel circulation valve. Background Technique

[0002] With the continuous increase in the demand for deep oil and gas resources in China, the frequency of high-pressure formations in the exploration and development process has increased significantly. For coiled tubing operations in high-pressure wells, it is particularly important to ensure the internal and external balanced pressure difference to avoid damage to the tubing caused by excessive pressure difference; at the same time, after the tubing is lowered in place, it is also necessary to effectively close the internal and external channels and ensure that the upper and lower channels can transmit pressure smoothly. Similar requirements also exist in some conventional oil wells, especially those where the packer at the lower end of the special pipe string is completely closed but reverse circulation well flushing operations are required. After the well flushing is completed, it is also necessary to close the circulation channel and maintain the pressure transmission function of the upper and lower channels to set the packer.

[0003] To meet the above complex operation requirements, the currently widely used technology is the ball-drop sleeve technology, and the spheres are mostly made of soluble materials. However, this solution is ineffective in gas wells and environments where dissolution conditions are not available and it is difficult to meet the actual needs.

[0004] Therefore, based on the above technical problems, it is necessary for those skilled in the art to develop a variable double-channel circulation valve. Content of the Utility Model

[0005] Aiming at the deficiencies in the prior art, the purpose of the utility model is to provide a variable double-channel circulation valve with strong applicability to alleviate the problem in the prior art that the switching between the internal and external channels and the upper and lower channels cannot be achieved under the condition that soluble balls cannot be used.

[0006] To achieve the above purpose, the utility model provides the following technical solutions:

[0007] A variable double-channel circulation valve technical solution includes an upper joint, an outer cylinder, a spacer, a ball seat, a piston, an inner sleeve, a lower joint, shear pins, Channel I, Channel II, and Channel III. One end of the outer cylinder is connected to the upper joint, and the other end is connected to the lower joint. The spacer and the ball seat are installed inside the inner sleeve. The piston is sleeved outside the inner sleeve and is fixed by shear pins. One end of the spacer is fitted and installed in the inner groove of the upper joint, and one end of the inner sleeve is fitted and installed in the inner groove of the lower joint.

[0008] As a preferred technical solution, the inner sleeve is provided with Channel I and Channel II, and the outer cylinder is provided with Channel III.

[0009] As a preferred technical solution, the spacer is provided with 4 elliptical grooves, and the upper end of the inner sleeve is provided with two round holes.

[0010] As a preferred technical solution, the inner diameter of the upper end of the piston is larger than that of the middle and lower ends, and there is an annular space between it and the inner sleeve.

[0011] Furthermore, the dual-channel transformation specifically includes the following process:

[0012] a. Lowering state: The inside and outside of the circulation valve are connected through Channel II and Channel III.

[0013] b. Ball injection state: After injecting the ball, the spaces above and below the ball seat are blocked. When pressure is applied, the piston moves downward after shearing the shear pins and contacts the lower sub. At this time, Channel II and Channel III are sealed, and the inside and outside are no longer connected.

[0014] c. Pressure transmission state: When continuing to apply pressure in the ball injection state, the pressure can be transmitted to the annular space between the piston and the inner sleeve through the 4 elliptical grooves on the spacer sleeve and the 2 round holes at the upper end of the inner sleeve, and then transmitted to the lower internal channel through Channel I.

[0015] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0016] The present utility model is a variable dual-channel circulation valve, which can effectively solve the problem of internal and external balance pressure difference during coiled tubing operations in high-pressure wells, and avoid damage to the tubing caused by excessive pressure difference. At the same time, after the tubing is lowered in place, the circulation valve can effectively close the internal and external channels and ensure smooth pressure transmission between the upper and lower channels to meet specific operation requirements. In addition, in some conventional oil wells, especially in the case where the packer at the lower end of the special pipe string is completely sealed but reverse circulation well flushing operations are required, the circulation channel can be closed after well flushing and the pressure transmission function between the upper and lower channels can be maintained to set the packer.

[0017] Through its unique structural design, the present utility model not only improves the safety of operations but also enhances the flexibility of operations. Under the condition that soluble balls cannot be used, such as in gas wells or environments without dissolution conditions, the present utility model can still effectively switch between the internal and external channels and the upper and lower channels, thereby meeting complex operation requirements.

[0018] In summary, the present utility model provides a variable dual-channel circulation valve with a simple structure, convenient operation, and strong applicability, having significant technical advantages and broad market application prospects. Description of the Drawings

[0019] Figure 1 It is a cross-sectional view schematic diagram of the variable dual-channel circulation valve of the present utility model;

[0020] Figure 2 It is a flow channel schematic diagram of the variable dual-channel circulation valve of the present utility model;

[0021] Figure 3The utility model is a schematic diagram of the ball-throwing pressure of the variable dual-channel circulation valve.

[0022] The markings in the above figure are: 1, upper joint; 2, outer tube; 3, spacer; 4, ball seat; 5, piston; 6, inner sleeve; 7, lower joint; 8, shear pin; 101, channel I; 102, channel II; 103, channel III. DETAILED DESCRIPTION

[0023] The features and exemplary embodiments of various aspects of the present invention will be described in detail below. In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. For those skilled in the art, the present invention can be implemented without the need for some of these specific details. The following description of the embodiments is only intended to provide a better understanding of the present invention by illustrating examples of the present invention.

[0024] like Figure 1 , Figure 2 and Figure 3 As shown, the utility model provides a technical solution for a variable dual-channel circulation valve: including an upper joint 1, an outer tube 2, a spacer 3, a ball seat 4, a piston 5, an inner sleeve 6, a lower joint 7, a shear pin 8, a channel I 101, a channel II 102 and a channel III 103. One end of the outer tube 2 is connected to the upper joint 1, and the other end is connected to the lower joint 7. The spacer 3 and the ball seat 4 are installed inside the inner sleeve 6, and the piston 5 is sleeved outside the inner sleeve 6 and fixed by the shear pin 8. One end of the spacer 3 is installed in the groove inside the upper joint 1, and one end of the inner sleeve 6 is installed in the groove inside the lower joint 7.

[0025] The inner sleeve 6 has a channel I 101 and a channel II 102 , and the outer sleeve 2 has a channel III 103 .

[0026] Among them, there are 4 elliptical grooves on the spacer 3, and two circular holes on the upper end of the inner sleeve 6. Specifically, the number of elliptical grooves on the spacer 3 can be adjusted to adapt to spheres of different sizes and different operating requirements. The number and position of the circular holes on the upper end of the inner sleeve 6 can also be adjusted according to actual needs to optimize the pressure transmission efficiency.

[0027] Among them, the inner diameter of the upper end of the piston 5 is larger than the inner diameter of the middle and lower ends, and there is an annulus between the piston 5 and the inner sleeve 6. Specifically, the difference between the inner diameter of the upper end and the inner diameter of the middle and lower ends of the piston 5 can be designed to be larger or smaller to change the size of the annulus, thereby affecting the sensitivity of pressure transmission.

[0028] Working method:

[0029] a. Lowering state: The inside and outside of the circulation valve are connected through channel II 102 and channel III 103 to ensure that the internal and external pressure difference is balanced during the lowering of the oil pipe.

[0030] b. Pitching state: After pitching, the upper and lower spaces of the ball seat 4 are blocked and pressurized. The piston 5 moves downward to contact the lower sub 7 after cutting the shear pin 8. At this time, the channel II 102 and the channel III 103 are sealed, and the inside and outside are no longer connected.

[0031] c. Pressure transmission state: Continue to pressurize in the pitching state. At this time, the pressure can be transmitted to the annulus between the piston 5 and the inner sleeve 6 through the 4 elliptical grooves on the spacer sleeve 3 and the two circular holes at the upper end of the inner sleeve 6, and then transmitted to the lower internal channel through the channel I 101.

[0032] Through the above embodiments, the variable double-channel circulation valve of the present invention is applicable to downhole workover operations and plugging operations, can adapt to a variety of pipe strings, and realizes functions such as balanced pressure difference, automatic grouting, and circulating well flushing. It has strong adaptability and brings a lot of convenience to the operation. By using the variable double-channel circulation valve, the construction process is less, the channel switching is reliable, the efficiency can be improved, the cost can be saved, and it can flexibly switch the working state according to different operating conditions and requirements to ensure the internal and external balanced pressure difference during coiled tubing operations in high-pressure wells, avoid damage to the tubing, and effectively close the circulation channel after specific operations are completed to maintain the pressure transmission function of the upper and lower channels.

[0033] The working principle and usage process of the present invention: After assembling the components of this solution in sequence, work according to the above embodiments in sequence according to actual needs, and these are all the working steps.

[0034] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution of the present invention and its inventive concept, makes equivalent substitutions or changes, and should be covered within the protection scope of the present invention.

[0035] In the description of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "coaxial", "bottom", "one end", "top", "middle", "the other end", "upper", "one side", "top", "inner", "front", "center", "both ends", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0036] In the present utility model, unless otherwise clearly defined and limited, terms such as "installation", "setting", "connection", "fixation", "swivel connection" and the like shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal connection of two components or the interaction relationship between two components. Unless otherwise clearly defined, for those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0037] According to the embodiments of the present utility model as described above, these embodiments do not describe all the details in detail, nor limit the utility model to only the specific embodiments. Obviously, according to the above description, many modifications and variations can be made. The present specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present utility model, so that those skilled in the art can make good use of the present utility model and its modified use based on the present utility model. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A variable dual-channel circulation valve, characterized in that, It includes an upper sub (1), an outer cylinder (2), a spacer sleeve (3), a ball seat (4), a piston (5), an inner sleeve (6), a lower sub (7), shear pins (8), passage I (101), passage II (102) and passage III (103). One end of the outer cylinder (2) is connected to the upper sub (1), and the other end is connected to the lower sub (7). The spacer sleeve (3) and the ball seat (4) are installed inside the inner sleeve (6). The piston (5) is sleeved outside the inner sleeve (6) and fixed by the shear pins (8). One end of the spacer sleeve (3) is fitted and installed in the inner groove of the upper sub (1), and one end of the inner sleeve (6) is fitted and installed in the inner groove of the lower sub (7).

2. The variable two-channel circulation valve according to claim 1, wherein: The inner sleeve (6) has passage I (101) and passage II (102), and the outer cylinder (2) has passage III (103).

3. The variable two-channel circulation valve according to claim 1, characterized in that: The spacer sleeve (3) has 4 elliptical grooves, and the upper end of the inner sleeve (6) has two round holes.

4. The variable two-channel circulation valve according to claim 3, characterized in that: The inner diameter of the upper end of the piston (5) is larger than that of the middle and lower ends, and there is an annular space between it and the inner sleeve (6).

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