Mechanical two-position four-way reversing structure

Abstract

The utility model discloses a mechanical two-position four-way reversing structure, including cylinder, the top of cylinder is equipped with gland, is equipped with upper piston, middle piston, lower piston in cylinder by piston connecting rod from top to bottom in proper order interval, and the outer wall of cylinder is passed through upper pressure relief pipe, lower pressure relief pipe, liquid inlet channel, upper liquid outlet channel and lower liquid outlet channel and is communicated, and upper pressure relief pipe is communicated with lower pressure relief pipe. The utility model discloses simple and convenient operation, full mechanical reversing, need not manual pressure relief, and only need once piston movement to complete liquid path switching, safe and reliable, multiple sealing design prevents high pressure leakage effectively, and prevents the risk of pressure accumulation, and the operation accident rate is reduced greatly, and high -efficient compatibility is applicable to continuous sand washing, positive and negative alternate sand washing, well washing and a variety of operation scenes, and sand washing efficiency is improved obviously, and environmental adaptability is strong, need not power drive, and it is especially suitable for remote oilfield or the operation environment of unstable power supply.

Description

Technical Field

[0001] This utility model relates to the field of oilfield well workover technology, and in particular to a mechanical two-position four-way reversing structure. Background Technology

[0002] In oilfield production operations, many tools require two-position four-way valves. Due to limited on-site power conditions, electromagnetic two-position four-way valves cannot be used directly; instead, mechanical structures must be relied upon to complete the reversing operation. For example, in continuous sand flushing operations in oilfields, the surface reversing valve must meet the following functional requirements: Position 1 is the inlet, connecting to the pump truck; Positions 2 and 3 are the outlets, connecting to the sand flushing tubing and the wellhead sand flushing self-sealing side, respectively; Position 4 is the pressure relief port, connecting to the liquid collection tank. When Position 1 inlet is connected to Position 3 outlet, Position 2 outlet must be connected to Position 4 pressure relief port; conversely, when Position 1 is connected to Position 2, Position 3 must be connected to Position 4.

[0003] Traditional commutation devices are complex in structure and have numerous components, making installation, commissioning, and maintenance difficult. This not only increases production costs but also reduces operating efficiency. Some commutation structures exhibit slow response times during commutation, failing to meet real-time requirements and impacting overall system performance. Furthermore, existing commutation structures are prone to wear and leakage during long-term use, reducing equipment stability and lifespan.

[0004] Currently, the surface-mounted reversing valves used in the field achieve pressure relief by connecting a check valve to the outlet via a three-way valve. During operation, the check valve must be manually opened to relieve pressure, and then closed again afterward. This design is not only cumbersome but also prone to causing system pressure buildup due to misoperation, leading to high-pressure fluid leaks or equipment damage and other safety accidents. Therefore, there is an urgent need for a reversing structure that is easy to operate, safe, and reliable to meet the needs of continuous sand flushing operations in oilfields.

[0005] A search revealed that publication number CN102155154B, titled "Automatic Reversing Device for Rock Drill Punch Pressure Control," relies on a hydraulic pump to provide pressure and a solenoid valve to assist in reset. Its core is "hydraulic reversing," requiring complex hydraulic pipelines (including throttle valves, check valves, and pressure reducing valves). It is suitable for driving rock drill punches, which is completely different from the application scenario and driving method of this application. Utility Model Content

[0006] To solve the above problems, this utility model provides a mechanical two-position four-way reversing structure. The mechanical action realizes the switching of fluid flow direction, which is particularly suitable for oilfield operation environments where power supply is inconvenient, and can significantly improve the efficiency and safety of sand flushing operations.

[0007] To solve the above-mentioned technical problems, the technical solution of this utility model is: a mechanical two-position four-way reversing structure, including a cylinder body, a pressure cap installed on the top of the cylinder body, and an upper piston, a middle piston, and a lower piston arranged sequentially from top to bottom through a piston connecting rod inside the cylinder body. The outer wall of the cylinder body is connected to an upper pressure relief pipe, a lower pressure relief pipe, a liquid inlet channel, an upper liquid outlet channel, and a lower liquid outlet channel, and the upper pressure relief pipe is connected to the lower pressure relief pipe.

[0008] Furthermore, the top of the piston connecting rod extends out of the pressure cap.

[0009] Furthermore, the upper cavity A is formed between the gland and the upper piston, the middle cavity B is formed between the upper piston and the middle piston, the lower cavity C is formed between the middle piston and the lower piston, and the bottom cavity D is formed between the lower piston and the bottom of the cylinder.

[0010] Furthermore, when the upper piston reaches the top dead center, the upper pressure relief pipe and the upper liquid outlet channel are connected to the middle cavity B, the liquid inlet channel and the lower liquid outlet channel are connected to the lower cavity C, and the lower pressure relief pipe is connected to the bottom cavity D.

[0011] Furthermore, when the lower piston reaches the bottom dead center, the upper pressure relief pipe is connected to the upper cavity A, the liquid inlet channel and the upper liquid outlet channel are both connected to the middle cavity B, and the lower pressure relief pipe and the lower liquid outlet channel are both connected to the lower cavity C.

[0012] Furthermore, the pressure relief pipe is located below the lower piston.

[0013] Furthermore, the pressure relief pipe is located above the lower piston.

[0014] Furthermore, the upper pressure relief pipe, lower pressure relief pipe, and liquid inlet channel are located on one side of the cylinder body, with the liquid inlet channel located between the upper pressure relief pipe and the lower pressure relief pipe.

[0015] Furthermore, the upper and lower liquid outlet channels are located on one side of the cylinder body.

[0016] Furthermore, the top of the piston connecting rod is connected to the lead screw.

[0017] The beneficial effects of this utility model are: 1. Easy to operate: Fully mechanical reversing, no manual depressurization required, hydraulic circuit switching can be completed with just one piston movement; 2. Safe and reliable: The multi-seal design effectively prevents high-pressure leakage, eliminates the risk of pressure buildup, and significantly reduces the accident rate. 3. High efficiency and compatibility: Suitable for various operation scenarios such as continuous sand flushing, alternating forward and reverse sand flushing, and well washing, significantly improving operation efficiency; 4. Strong environmental adaptability: It does not require electric power and is particularly suitable for remote oil fields or operating environments with unstable power supply. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of the lower piston reaching the bottom dead center of this utility model; Figure 2 This is a schematic diagram of the structure of the upper piston reaching the top dead center of this utility model.

[0019] The components are: 1. Cylinder body; 2. Pressure cap; 3. Piston connecting rod; 4. Upper piston; 5. Middle piston; 6. Lower piston; 7. Upper pressure relief pipe; 8. Lower pressure relief pipe; 9. Liquid inlet channel; 10. Upper liquid outlet channel; 11. Lower liquid outlet channel. Detailed Implementation

[0020] The following is in conjunction with the appendix Figure 1 , 2 The technical solution of this utility model has been clearly and completely described. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0021] The present invention is described in detail below through specific embodiments, but this does not limit the scope of protection of the present invention. Unless otherwise specified, the experimental methods used in the present invention are all conventional methods, and the experimental equipment, materials, reagents, etc. used can all be obtained commercially.

[0022] In the description of this utility model, it should be noted that the terms "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," and "third" are used only for distinction and should not be construed as indicating or implying relative importance.

[0023] Furthermore, the technical features involved in the different embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.

[0024] Example 1 A mechanical two-position four-way reversing structure includes a cylinder body 1, a pressure cap 2 installed on the top of the cylinder body 1, and an upper piston 4, a middle piston 5, and a lower piston 6 arranged sequentially from top to bottom through a piston connecting rod 3 inside the cylinder body 1. The outer wall of the cylinder body 1 is connected to an upper pressure relief pipe 7, a lower pressure relief pipe 8, a liquid inlet channel 9, an upper liquid outlet channel 10, and a lower liquid outlet channel 11. The upper pressure relief pipe 7 and the lower pressure relief pipe 8 are connected.

[0025] This invention significantly improves equipment performance. The optimized structure enables rapid and accurate reversing actions, greatly shortening the reversing response time and improving system efficiency. Furthermore, the simplified structural design reduces the number of parts, lowering the equipment failure rate and further enhancing overall equipment performance.

[0026] This invention addresses the diverse needs of various operating conditions. In practical engineering applications, different operating conditions place varying requirements on the reversing structure. For example, in oilfield operations where power supply is inconvenient, a suitable and safe power source is needed; in situations requiring frequent reversing, the reversing structure must possess fast and stable reversing performance; and in situations with high sealing requirements, the reversing structure must effectively prevent leakage. The core advantage of this mechanical two-position four-way reversing structure lies in its fully mechanical operation, requiring no electric drive, making it suitable for various oilfield operating environments; it possesses excellent versatility and adaptability, and can meet the diverse needs under different operating conditions.

[0027] Example 2 A mechanical two-position four-way reversing structure includes a cylinder body 1, with a pressure cap 2 mounted on the top of the cylinder body 1. Inside the cylinder body 1, an upper piston 4, a middle piston 5, and a lower piston 6 are arranged sequentially from top to bottom via a piston connecting rod 3. The outer wall of the cylinder body 1 is connected to an upper pressure relief pipe 7, a lower pressure relief pipe 8, a liquid inlet channel 9, an upper liquid outlet channel 10, and a lower liquid outlet channel 11. The upper pressure relief pipe 7 and the lower pressure relief pipe 8 are connected. The upper pressure relief pipe 7, the lower pressure relief pipe 8, and the liquid inlet channel 9 are located on one side of the cylinder body 1, with the liquid inlet channel 9 located between the upper pressure relief pipe 7 and the lower pressure relief pipe 8. The upper liquid outlet channel 10 and the lower liquid outlet channel 11 are located on the other side of the cylinder body 1. The top of the piston connecting rod 3 extends out of the pressure cap 2, and the top of the piston connecting rod 3 is connected to a lead screw. The pressure cap 2 and the upper piston 4 form the upper cavity A; the upper piston 4 and the middle piston 5 form the middle cavity B; the middle piston 5 and the lower piston 6 form the lower cavity C; and the lower piston 6 and the bottom of the cylinder 1 form the bottom cavity D. When the upper piston 4 reaches its top dead center, the upper pressure relief pipe 7 and the upper liquid outlet channel 10 are both connected to the middle cavity B; the liquid inlet channel 9 and the lower liquid outlet channel 11 are both connected to the lower cavity C; and the lower pressure relief pipe 8 is connected to the bottom cavity D. The lower pressure relief pipe 8 is located below the lower piston 6. When the lower piston 6 reaches its bottom dead center, the upper pressure relief pipe 7 is connected to the upper cavity A; the liquid inlet channel 9 and the upper liquid outlet channel 10 are both connected to the middle cavity B; and the lower pressure relief pipe 8 and the lower liquid outlet channel 11 are both connected to the lower cavity C. The lower pressure relief pipe 8 is located above the lower piston 6.

[0028] Working principle: This structure achieves a two-position four-way function through the reciprocating motion of piston rod 3 (up / down or left / right). Details are as follows: The lower piston 6 is located at the bottom of cylinder 1. At this time, the upper piston 4 closes the annulus between the upper pressure relief pipe 7, and the middle piston 5 closes the annulus between the liquid inlet channel 9 and the lower liquid outlet channel 11. Simultaneously, the liquid inlet channel 9 is connected to the upper liquid outlet channel 10, forming the main working channel and providing the necessary liquid flow path for sand flushing operations. At the same time, the lower liquid outlet channel 11 is connected to the lower pressure relief pipe 8 to release pressure, ensuring that the system pressure is within a safe range and avoiding damage to the equipment due to excessive pressure, thus preparing for the next conversion operation.

[0029] When the upper piston 4 moves to the upper end of cylinder 1, the upper piston 4 and the middle piston 5 work together to close the annulus between the inlet channel 9 and the upper outlet channel 10, and the lower piston 6 closes the annulus between the lower pressure relief pipe 8 and the lower outlet channel 11. At the same time, the inlet channel 9 and the lower outlet channel 11 are connected, completing the fluid circuit reversal. This flexible fluid circuit switching method can meet the needs of different stages and working conditions in continuous sand flushing operations in oilfields, improving operational efficiency and quality.

[0030] This structure is specifically designed for continuous sand flushing operations in oilfields, with a clear and efficient connection method. The inlet channel 9 connects to the pump truck, which provides the power and fluid flow required for sand flushing; the outlet channel 10 connects to the sand flushing tubing, delivering the sand flushing fluid to the downhole work site; the lower outlet channel 11 connects to the wellhead's self-sealing side for effective wellhead sealing and proper discharge of the sand flushing fluid; the upper pressure relief pipe 7 and lower pressure relief pipe 8 connect to the collection tank, used to collect and treat the high-pressure fluid generated during sand flushing, ensuring pressure balance and safe operation of the entire system.

[0031] The structure is smaller and lighter, making it easier to install and maintain on-site. It reduces installation space requirements and difficulty, while also facilitating routine maintenance by staff, minimizing equipment downtime, and improving equipment efficiency and lifespan.

[0032] The embodiments described above are merely preferred embodiments of this utility model, and not all feasible embodiments of this utility model. For those skilled in the art, any obvious modifications made without departing from the principles and spirit of this utility model should be considered to be included within the scope of protection of the claims of this utility model. Although this utility model has been described above with reference to embodiments, various modifications can be made and components can be replaced with equivalents without departing from the scope of this utility model. In particular, as long as there is no technical conflict, the features in the embodiments disclosed in this utility model can be combined with each other in any way. The lack of an exhaustive description of these combinations in this specification is merely for the sake of brevity and resource conservation. Therefore, this utility model is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A mechanical two-position four-way commutator structure, characterized in that, The cylinder (1) includes a cylinder body (1), a pressure cap (2) is installed on the top of the cylinder body (1), and an upper piston (4), a middle piston (5) and a lower piston (6) are arranged in sequence from top to bottom through a piston connecting rod (3) inside the cylinder body (1). The outer wall of the cylinder body (1) is connected to an upper pressure relief pipe (7), a lower pressure relief pipe (8), a liquid inlet channel (9), an upper liquid outlet channel (10) and a lower liquid outlet channel (11). The upper pressure relief pipe (7) and the lower pressure relief pipe (8) are connected.

2. The mechanical two-position four-way commutator structure according to claim 1, characterized in that, The top of the piston rod (3) extends out of the pressure cap (2).

3. The mechanical two-position four-way commutator structure according to claim 1, characterized in that, The pressure cap (2) and the upper piston (4) form an upper cavity A, the upper piston (4) and the middle piston (5) form a middle cavity B, the middle piston (5) and the lower piston (6) form a lower cavity C, and the lower piston (6) and the bottom of the cylinder (1) form a bottom cavity D.

4. The mechanical two-position four-way commutator structure according to claim 3, characterized in that, When the upper piston (4) reaches the top dead center, the upper pressure relief pipe (7) and the upper liquid outlet channel (10) are connected to the middle cavity B, the liquid inlet channel (9) and the lower liquid outlet channel (11) are connected to the lower cavity C, and the lower pressure relief pipe (8) is connected to the bottom cavity D.

5. The mechanical two-position four-way commutator structure according to claim 3, characterized in that, When the lower piston (6) reaches the bottom dead center, the upper pressure relief pipe (7) is connected to the upper cavity A, the liquid inlet channel (9) and the upper liquid outlet channel (10) are both connected to the middle cavity B, and the lower pressure relief pipe (8) and the lower liquid outlet channel (11) are both connected to the lower cavity C.

6. The mechanical two-position four-way commutator structure according to claim 4, characterized in that, The pressure relief pipe (8) is located below the lower piston (6).

7. The mechanical two-position four-way commutator structure according to claim 5, characterized in that, The pressure relief pipe (8) is located above the lower piston (6).

8. The mechanical two-position four-way commutator structure according to claim 1, characterized in that, The upper pressure relief pipe (7), lower pressure relief pipe (8), and liquid inlet channel (9) are located on one side of the cylinder body (1), and the liquid inlet channel (9) is located between the upper pressure relief pipe (7) and the lower pressure relief pipe (8).

9. The mechanical two-position four-way commutator structure according to claim 1, characterized in that, The upper liquid outlet channel (10) and the lower liquid outlet channel (11) are located on one side of the cylinder body (1).

10. The mechanical two-position four-way commutator structure according to claim 2, characterized in that, The top of the piston rod (3) is connected to the lead screw.

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