Online adjustment automatic recirculation valve structure

Abstract

The utility model discloses an on-line adjustment automatic recirculation valve structure, which relates to the technical field of automatic recirculation valves, and comprises a valve body, a valve seat assembly, a control assembly, a valve clack, a spring, a guide sleeve, a valve cover and a bypass check valve, the valve body is of a three-way structure and is provided with a first opening, a second opening and a third opening, the end, close to the second opening, of the valve body is fixedly provided with the valve deck, the valve seat assembly is arranged in the valve body, the end, close to the valve deck, of the valve seat assembly is slidably provided with the valve clack, and the control assembly is arranged in the valve seat assembly. A guide sleeve is arranged at the end, away from the valve seat assembly, of the valve clack in a matched mode, springs are arranged on the outer sides of the valve clack and the guide sleeve, and a bypass check valve is arranged at the third opening in the valve body. The valve seat assembly, the control assembly, the valve clack, the spring, the guide sleeve and the valve deck are all coaxially arranged with the first opening and the second opening. According to the invention, disassembly-free and on-line adjustment operation can be realized, and the whole adjustment process is more direct and more accurate.

Description

Technical Field

[0001] This utility model relates to the field of automatic recirculation valve technology, specifically to an online regulating automatic recirculation valve structure. Background Technology

[0002] Automatic recirculation valves are critical devices in fluid control systems, primarily used to prevent pumps from overheating, cavitation, or mechanical damage caused by low or no flow conditions. To accurately match system operating requirements and ensure the valve dynamically adjusts its flow capacity when the main flow fluctuates, the CV value (flow coefficient) of the automatic recirculation valve needs timely adjustment. A CV value that is too small may result in insufficient bypass flow, failing to protect the pump; a CV value that is too large may lead to energy waste. By scientifically setting the CV value, precise flow control can be achieved, maintaining a minimum safe flow to prevent pump cavitation or overheating while optimizing system energy efficiency. This is a key technical means to ensure the stable and efficient operation of fluid systems.

[0003] The existing automatic recirculation valve structure requires disassembling the valve and removing parts such as the valve disc when adjusting the CV value. Subsequently, the adjusting nut needs to be shortened or a shim of appropriate thickness needs to be added to achieve the CV value adjustment. Disassembling the valve may cause failure or damage to the central connecting gasket, resulting in damage to internal parts and sealing rings, affecting the performance of the automatic recirculation valve. Adding an adjusting shim or shortening the adjusting nut cannot meet the high-precision thickness requirements and is time-consuming and material-intensive. Disassembling the valve is also time-consuming and labor-intensive, leading to low adjustment efficiency and increased costs.

[0004] Therefore, an online adjustable automatic recirculation valve structure is needed to solve the above-mentioned technical problems. Utility Model Content

[0005] To achieve the above objectives, this utility model provides the following technical solution: an online regulating automatic recirculation valve structure, comprising: a valve body, a valve seat assembly, a control assembly, a valve disc, a spring, a guide sleeve, a valve cover, and a bypass check valve;

[0006] The valve body is a three-way structure with a first opening, a second opening, and a third opening. The valve cover is fixedly installed at the end of the valve body near the second opening. The valve seat assembly is provided inside the valve body. The valve disc is slidably disposed at the end of the valve seat assembly near the valve cover. The control component is disposed inside the valve seat assembly. The guide sleeve is fitted at the end of the valve disc away from the valve seat assembly. The spring is disposed on the outside of the valve disc and the guide sleeve. The bypass check valve is disposed inside the valve body at the position of the third opening.

[0007] The valve seat assembly, the control assembly, the valve disc, the spring, the guide sleeve, and the valve cover are all coaxially arranged with the first opening and the second opening;

[0008] The control assembly includes: a valve disc push rod, a mounting head, a control head, an external thread, and a limiting hole;

[0009] Wherein, one end of the valve disc push rod is the control head, and the other end is the mounting head. The outer wall of the control head is provided with the external thread, and the control head has the limiting hole at the position of the external thread.

[0010] The control head is connected to the small valve disc assembly via the external thread, and the mounting head is disposed inside the valve disc via the valve seat assembly and abuts against the bottom of the inner hole of the valve disc near the valve seat assembly.

[0011] Furthermore, as a preferred embodiment, the valve body includes: a main passage, a bypass passage, a main inlet, a main outlet, and a bypass outlet;

[0012] The valve body is provided with a main passage and a bypass passage, which are connected by the valve seat assembly. The first opening is connected to the main passage through the main inlet, the second opening is connected to the main passage through the main outlet, and the third opening is connected to the bypass passage through the bypass outlet.

[0013] Furthermore, as a preferred embodiment, the valve seat assembly includes: a bypass valve seat sleeve, a first flow passage, a connector, and a second flow passage;

[0014] The bypass valve seat sleeve has a hollow structure, with one end located inside the valve body and the other end located inside the valve disc via the connector;

[0015] The bypass valve seat sleeve has a first flow hole at one end away from the valve disc, and the inside of the bypass valve seat sleeve is connected to the main passage through the first flow hole;

[0016] The bypass valve seat has a second flow hole in the middle, and the inside of the bypass valve seat is connected to the bypass passage through the second flow hole.

[0017] Furthermore, as a preferred embodiment, the inner wall of the bypass valve seat is provided with multiple keyways.

[0018] Furthermore, as a preferred embodiment, the control component further includes: a spline;

[0019] The valve push rod has multiple splines arranged around its outer circumference, and each spline corresponds to a keyway. The valve push rod is connected to the bypass valve seat via the multiple splines and the multiple keyways.

[0020] Furthermore, as a preferred embodiment, the small valve assembly includes: a small valve disc, a self-made nut, an internal thread, and a plug groove;

[0021] The small valve disc is rotatably mounted on the outer wall of the control head, and the self-made nut has an internal thread that mates with the external thread. The self-made nut is threadedly connected to the control head at the position with the external thread, and the small valve disc is fixedly connected to the self-made nut.

[0022] The small valve disc has the insertion slot.

[0023] Furthermore, as a preferred embodiment, a cotter pin is inserted into the insertion slot and the limiting hole for limiting.

[0024] Furthermore, as a preferred embodiment, the valve disc is provided with a valve disc sealing surface, which coincides with the sealing surface of the valve body.

[0025] Compared with the prior art, this utility model provides an online adjustable automatic recirculation valve structure, which has the following beneficial effects:

[0026] Advantage 1: This application enables online adjustment without disassembly. Specifically, the control head of the control component in this application is located directly near the end of the first flow orifice, and actively adjusts the flow area of ​​the first flow orifice through the threaded engagement with the integrated component of the small valve disc and the self-made nut, thereby completing the adjustment of the CV value. The entire adjustment process is more direct and precise. There is no need to disassemble the automatic recirculation valve, no need to separately process the nut gasket or thin the nut, and no need to indirectly change the flow area of ​​the first flow orifice by altering the structure at the end furthest from the first flow orifice. Operation is simple and highly accurate.

[0027] Advantage 2: When adjusting the flow area of ​​the first flow orifice, this application makes an adaptive change to the end of the valve push rod away from the first flow orifice, namely, by adding a spline mating connection. The spline and keyway mating connection simultaneously achieves three different functions: circumferential anti-rotation, increased stability, and correlation with CV value adjustment. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of an online regulating automatic recirculation valve.

[0029] Figure 2 This is a schematic diagram of the structure of a control component for an online regulating automatic recirculation valve;

[0030] Figure 3 Adjusting the state of a small valve disc assembly in an online regulating automatic recirculation valve structure. Figure 1 ;

[0031] Figure 4 Adjusting the state of a small valve disc assembly in an online regulating automatic recirculation valve structure. Figure 2 ;

[0032] Figure 5 A schematic diagram of the spline structure of an online regulating automatic recirculation valve;

[0033] In the diagram: 1. Valve body; 11. Main passage; 12. Bypass passage; 13. Main inlet; 14. Main outlet; 15. Bypass outlet; 2. Valve seat assembly; 21. Bypass valve seat sleeve; 211. Keyway; 22. First flow hole; 23. Connector; 24. Second flow hole; 3. Control assembly; 31. Valve disc push rod; 32. Mounting head; 33. Control head; 34. External thread; 35. Limiting hole; 36. Spline; 4. Valve disc; 41. Valve disc sealing surface; 5. Spring; 6. Guide sleeve; 7. Valve cover; 8. Bypass check valve; 9. Small valve disc assembly; 91. Small valve disc; 92. Self-made nut; 93. Internal thread; 94. Insert groove; 10. Cotter pin. Detailed Implementation

[0034] Please see Figures 1-5 This utility model provides an online regulating automatic recirculation valve structure, including: valve body 1, valve seat assembly 2, control assembly 3, valve disc 4, spring 5, guide sleeve 6, valve cover 7, and bypass check valve 8;

[0035] The valve body 1 is a three-way structure with a first opening, a second opening and a third opening. A valve cover 7 is fixedly installed at the end of the valve body 1 near the second opening. A valve seat assembly 2 is installed inside the valve body 1. A valve disc 4 is slidably installed at the end of the valve seat assembly 2 near the valve cover 7. A control assembly 3 is installed inside the valve seat assembly 2. A guide sleeve 6 is installed at the end of the valve disc 4 away from the valve seat assembly 2. A spring 5 is installed on the outside of the valve disc 4 and the guide sleeve 6. A bypass check valve 8 is installed inside the valve body 1 at the position of the third opening.

[0036] The valve seat assembly 2, control assembly 3, valve disc 4, spring 5, guide sleeve 6, and valve cover 7 are all coaxially arranged with the first opening and the second opening.

[0037] In this embodiment, please refer to Figure 1As shown, the valve seat assembly 2, control assembly 3, valve disc 4, spring 5, guide sleeve 6, and valve cover 7 are all coaxially aligned with the first and second openings. This ensures smooth fluid flow and reduces the risk of jamming, which is a fundamental requirement for ensuring overall assembly accuracy. The coaxiality deviation must be controlled within 0.02mm (this value is only an example and can be determined according to design requirements).

[0038] In a preferred embodiment, this application provides a structural basis for online adjustment by integrating the control component 3 and the small valve disc assembly 9. This allows for adjustment of the CV value of the automatic recirculation valve without disassembling the valve, protecting the valve seals and internal parts from damage. It should be noted that the spring 5 provides a restoring force to the valve disc 4. When the main flow rate increases, the fluid's thrust on the valve disc 4 overcomes the spring force of the spring 5, causing the valve disc 4 to move away from the valve seat assembly 2. This increases the main flow area, and the bypass check valve 8 prevents reverse flow of bypass fluid, avoiding system pressure fluctuations caused by fluid impact.

[0039] Control component 3 includes: valve disc push rod 31, mounting head 32, control head 33, external thread 34, and limiting hole 35;

[0040] Among them, one end of the valve disc push rod 31 is a control head 33, and the other end is a mounting head 32. The outer wall of the control head 33 is provided with an external thread 34, and a limit hole 35 is opened at the position of the external thread 34 in the control head 33.

[0041] The control head 33 is connected to the small valve disc assembly 9 via the external thread 34, and the mounting head 32 is located inside the valve disc 4 via the valve seat assembly 2 and abuts against the bottom of the inner hole of the valve disc 4 near the valve seat assembly 2.

[0042] Furthermore, the valve body 1 includes: a main passage 11, a bypass passage 12, a main inlet 13, a main outlet 14, and a bypass outlet 15;

[0043] The valve body 1 is provided with a main passage 11 and a bypass passage 12. The main passage 11 and the bypass passage 12 are connected through the valve seat assembly 2. The first opening is connected to the main passage 11 through the main inlet 13, the second opening is connected to the main passage 11 through the main outlet 14, and the third opening is connected to the bypass passage 12 through the bypass outlet 15.

[0044] In this embodiment, please refer to Figure 1 As shown, the three-way structure of valve body 1 is the basis for achieving flow separation between the main passage 11 and the bypass passage 12. The main passage 11 is used to transport the main flow fluid, and the bypass passage 12 is used to transport the bypass return fluid. The two are connected through valve seat assembly 2 to achieve flow distribution. The diameters of the main inlet 13, the main outlet 14, and the bypass outlet 15 need to be determined according to the design flow rate. Usually, the diameter of the main inlet 13 is larger than the diameter of the bypass outlet 15 to meet the high flow rate transport requirements of the main passage 11.

[0045] In this embodiment, the fluid flow path is as follows: fluid enters the main passage 11 from the main inlet 13, a portion of the fluid flows directly out from the main outlet 14 (main passage flow), and the other portion of the fluid enters the bypass passage 12 through the valve seat assembly 2, and then flows out from the bypass outlet 15 (bypass flow), thus achieving flow diversion. When the main passage flow decreases, the bypass flow automatically increases to ensure a minimum safe flow and prevent cavitation or overheating.

[0046] Furthermore, the valve seat assembly 2 includes: a bypass valve seat sleeve 21, a first flow passage 22, a connector 23, and a second flow passage 24;

[0047] The bypass valve seat sleeve 21 has a hollow structure inside, with one end set inside the valve body 1 and the other end set inside the valve disc 4 through the connector 23.

[0048] The bypass valve seat sleeve 21 is provided with a first flow hole 22 at the end away from the valve disc 4, and the inside of the bypass valve seat sleeve 21 is connected to the main passage 11 through the first flow hole 22.

[0049] A second flow hole 24 is provided in the middle of the bypass valve seat sleeve 21, and the inside of the bypass valve seat sleeve 21 is connected to the bypass passage 12 through the second flow hole 24.

[0050] In this embodiment, please refer to Figure 2 As shown, the bypass valve seat 21 has a hollow structure. The first flow-through hole 22 is used to achieve fluid communication between the main passage 11 and the inside of the bypass valve seat 21, and the second flow-through hole 24 is used to achieve fluid communication between the inside of the bypass valve seat 21 and the bypass passage 12. The diameter and number of the two flow-through holes need to be determined according to the design CV value range. It should be noted that the flow area of ​​the first flow-through hole 22 is a key factor in determining the CV value.

[0051] Furthermore, the inner wall of the bypass valve seat 21 is provided with multiple keyways 211.

[0052] In this embodiment, please refer to Figure 2 and Figure 5 As shown, the number of keyways 211 is usually 3-4 (the number of keyways 211 is only an example and can be determined according to design requirements). The depth, width and surface roughness of the keyway 211 must meet the specified requirements to ensure precise fit with the valve push rod 31.

[0053] Furthermore, control component 3 also includes: spline 36;

[0054] The valve push rod 31 has multiple splines 36 arranged around its outer circumference. Each spline 36 corresponds to a keyway 211. The valve push rod 31 is connected to the bypass valve seat 21 via the multiple splines 36.

[0055] Furthermore, the small valve assembly 9 includes: a small valve 91, a self-made nut 92, an internal thread 93, and a plug groove 94;

[0056] Among them, the small valve disc 91 is rotatably mounted on the outer wall of the control head 33, and the self-made nut 92 is provided with an internal thread 93 that mates with the external thread 34. The self-made nut 92 is threadedly connected to the control head 33 at the position with the external thread 34, and the small valve disc 91 is fixedly connected to the self-made nut 92.

[0057] The small valve disc 91 has a insertion slot 94.

[0058] In this embodiment, please refer to Figure 2 , Figure 3 and Figure 4 As shown, the valve push rod 31 must be made of high-strength stainless steel (such as 316L) to ensure sufficient compressive strength and corrosion resistance. The rod diameter must be determined according to the system pressure. The external thread 34 on the outer wall of the control head 33 is used to mate with the self-made nut 92 of the small valve assembly 9. The thread accuracy must meet the design requirements to ensure smooth thread engagement and adjustment accuracy. The small valve 91 is connected to the outer wall of the control head 33 to cover or expose the first flow hole 22 (adjusting the flow area of ​​the first flow hole 22). Its material must be wear-resistant (such as hard alloy), and the end face flatness error must not exceed 0.01mm to ensure the covering effect of the first flow hole 22.

[0059] In this embodiment, the number and size of splines 36 correspond one-to-one with the keyways 211. The tooth height and tooth width of the splines 36 must match those of the keyways 211, and the surface of the splines 36 needs to be hardened to improve wear resistance. A self-made nut 92 engages with the external thread 34 of the control head 33 via its internal thread 93, providing power for the axial movement of the small valve disc 91. The material of the self-made nut 92 must match that of the valve disc push rod 31 (e.g., 316L stainless steel) to prevent electrochemical corrosion. The pitch of the external thread 34 needs to be determined according to the CV value adjustment accuracy requirements to ensure that the system operating conditions are met. The accuracy of the internal thread 93 must be consistent with that of the external thread 34, and the thread surface needs to be lubricated (applied with high-temperature grease) to reduce frictional resistance in the thread engagement and ensure smooth adjustment.

[0060] For a preferred embodiment, please refer to Figure 3 and Figure 4 As shown, when the system operating conditions change and the CV value (flow coefficient) of the automatic recirculation valve needs to be adjusted, there is no need to disassemble the valve. Precise online adjustment can be achieved directly through the following steps:

[0061] First, confirm that the automatic recirculation valve is in working condition, record the current flow rate of the main passage 11, the flow rate of the bypass passage 12, and the system pressure parameters, and prepare special adjustment tools (such as an Allen wrench or special calipers) to ensure that they can be matched with the self-made nut 92 to avoid damaging the small valve disc assembly 9 during the adjustment process.

[0062] Next, use an auxiliary tool to remove the cotter pin 10 inserted into the insertion slot 94 and the limiting hole 35. Be careful to keep the cotter pin 10 to prevent loss. At this time, the homemade nut 92 is released from the circumferential limit and can rotate around the axis of the control head 33.

[0063] Finally, by rotating the self-made nut 92 using a special adjusting tool, the small valve disc 91 will rotate synchronously due to its fixed connection with the nut 92. Under the threaded engagement of the self-made nut 92 and the control head 33, the small valve disc 91 will move axially along the valve disc push rod 31, adjusting its relative distance with the valve disc push rod 31 from L1 to L3 (e.g., ...). Figure 3 and Figure 4 As shown in the figure, L1 > L3), and then adjust the relative distance L2 between it and the inner wall of the first flow hole 22 to change to L4 (as shown in the figure). Figure 3 and Figure 4 As shown in the diagram, L2 > L4. At this point, the flow area of ​​the first flow orifice 22 is reduced, the flow rate to the bypass passage 12 decreases, and the CV value decreases accordingly. When it is necessary to increase the CV value, simply reverse the rotation of the self-made nut 92.

[0064] It is important to note that during the adjustment process, the flow rates of the main passage 11 and bypass passage 12 should be monitored in real time. When the flow rate reaches the expected operating condition, stop rotating the self-made nut 92. Reinsert the cotter pin 10 into the insertion slot 94 and the limiting hole 35 to complete the limiting and fixing of the small valve disc assembly 9, preventing it from rotating on its own under fluid impact and ensuring stable adjustment. After adjustment, continuously monitor the system operating parameters to confirm that the flow rates of the main passage 11 and bypass passage 12 are stable within the expected range, and that the automatic recirculation valve has no leakage, abnormal noise, or other abnormalities. At this point, the online CV value adjustment operation is complete.

[0065] In a preferred embodiment, the control head 33 of the control component 3 is located directly near the end of the first flow-through orifice 22. Through the threaded engagement with the integrated assembly of the small valve disc 91 and the self-made nut 92, the flow area of ​​the first flow-through orifice 22 is actively adjusted, thereby completing the adjustment of the CV value. The entire adjustment process is more direct and precise. There is no need to disassemble the automatic recirculation valve, no need to separately process the nut gasket or thin the nut, and no need to indirectly change the flow area of ​​the first flow-through orifice 22 by altering the structure at the end furthest from the first flow-through orifice 22. Operation is simple and highly accurate.

[0066] In a preferred embodiment, when adjusting the flow area of ​​the first flow hole 22, this application makes an adaptive change to the end of the valve push rod 31 away from the first flow hole 22, namely, by adding a spline 36 mating connection. The mating connection between the spline 36 and the keyway 211 simultaneously achieves three different functions:

[0067] First, circumferential anti-rotation: The fit between the spline 36 and the keyway 211 restricts the circumferential rotation of the valve disc push rod 31. When the self-made nut 92 of the small valve disc assembly 9 is rotated, the valve disc push rod 31 will not rotate synchronously with the self-made nut 92, ensuring that the thread adjustment can be accurately converted into the axial displacement of the small valve disc 91, avoiding adjustment errors.

[0068] Second, it increases stability: the cooperation between spline 36 and keyway 211 provides multi-directional support for valve disc push rod 31, reducing radial sway of valve disc push rod 31. Especially when valve body 1 is installed horizontally, it can counteract the radial offset caused by the gravity of valve disc push rod 31, ensuring that valve disc 4 can move flexibly along the axial direction, avoiding valve disc 4 jamming due to offset, and ensuring normal valve operation.

[0069] Third, the relationship with CV value adjustment: the anti-rotation function of spline 36 is the basis for ensuring accurate CV value adjustment. If valve push rod 31 rotates with self-made nut 92, it will cause adjustment error, which will affect the flow area and CV value of the first flow hole 22. The cooperation between spline 36 and keyway 211 can effectively avoid this problem.

[0070] Furthermore, a cotter pin 10 is inserted into the insertion slot 94 and the limiting hole 35 for limiting.

[0071] In this embodiment, the insertion slot 94 is used to insert the cotter pin 10 and cooperates with the limiting hole 35 of the control head 33 to limit the small valve assembly 9. The width of the insertion slot 94 needs to be slightly larger than the diameter of the cotter pin 10 to ensure that the cotter pin 10 can be flexibly inserted and removed. The number and position of the limiting hole 35 and the insertion slot 94 can be adjusted according to design requirements.

[0072] In a preferred embodiment, during the operation of the automatic recirculation valve, the fluid generates axial thrust and circumferential torque on the small valve disc assembly 9. The cotter pin 10 restricts the circumferential rotation of the small valve disc assembly 9, preventing it from rotating on its own in the non-adjustment state, which would cause changes in the flow area of ​​the first flow orifice 22, thus ensuring stable CV value and avoiding system flow fluctuations. The cotter pin 10 can be disassembled and installed without special tools, requiring only pliers. This simple and quick operation provides a convenient method for limiting and fixing the CV value online, further demonstrating the advantages of online adjustment without disassembly.

[0073] Furthermore, the valve disc 4 is provided with a valve disc sealing surface 41, which coincides with the sealing surface of the valve body 1.

[0074] In this embodiment, the sealing surface of the valve body 1 must be made of a material that matches the sealing surface of the valve disc 41, and the two must completely overlap, with the overlap deviation meeting the design requirements. This application will not cause fluid leakage from the main passage 11 to the bypass passage 12, or fluid leakage from the bypass passage 12 to the main passage 11, thus avoiding system flow distribution disorder, ensuring reliable sealing, and guaranteeing safe system operation.

[0075] In a preferred embodiment, when the flow rate in the main passage 11 decreases, the spring force of the spring 5 pushes the valve disc 4 to move closer to the valve seat assembly 2, and the valve disc sealing surface 41 is tightly fitted with the sealing surface of the valve body 1, thus sealing the main passage 11. At this time, the fluid mainly flows through the bypass passage 12. When the flow rate in the main passage 11 increases, the fluid thrust overcomes the spring force of the spring 5, the valve disc 4 moves, the valve disc sealing surface 41 separates from the sealing surface of the valve body 1, the flow area of ​​the main passage 11 increases, and the main passage 11 is ensured to transport fluid normally.

[0076] In practice, first, confirm that the automatic recirculation valve is in working condition, record the current flow rate of the main passage 11, the flow rate of the bypass passage 12, and the system pressure parameters, and prepare a special adjustment tool (such as an Allen wrench or special calipers) to ensure that it is compatible with the self-made nut 92, avoiding damage to the small valve disc assembly 9 during adjustment. Second, use an auxiliary tool to remove the cotter pin 10 inserted into the insertion slot 94 and the limiting hole 35, being careful to keep the cotter pin 10 to prevent loss. At this time, the self-made nut 92 is released from its circumferential limit and can rotate around the axis of the control head 33. Finally, rotate the self-made nut 92 using the special adjustment tool. Since the self-made nut 92 is fixedly connected to the small valve disc 91, the small valve disc 91 will rotate synchronously. Under the threaded engagement of the self-made nut 92 and the control head 33, the small valve disc 91 will move axially along the valve disc push rod 31, adjusting the relative distance between it and the valve disc push rod 31 from L1 to L3 (e.g., ...). Figure 3 and Figure 4 As shown in the figure, L1 > L3), and then adjust the relative distance L2 between it and the inner wall of the first flow hole 22 to change to L4 (as shown in the figure). Figure 3 and Figure 4 As shown in the diagram, L2 > L4. At this point, the flow area of ​​the first flow orifice 22 is reduced, the flow rate to the bypass passage 12 decreases, and the CV value decreases accordingly. When it is necessary to increase the CV value, simply reverse the rotation of the self-made nut 92.

[0077] The above are merely preferred embodiments of this utility model, but the scope of protection of this utility model is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in this utility model, based on the technical solution and inventive concept of this utility model, should be included within the scope of protection of this utility model.

Claims

1. An online adjustable automatic recirculation valve structure, characterized by: include: Valve body (1), valve seat assembly (2), control assembly (3), valve disc (4), spring (5), guide sleeve (6), valve cover (7), and bypass check valve (8); The valve body (1) is a three-way structure with a first opening, a second opening and a third opening. The valve cover (7) is fixedly installed at the end of the valve body (1) near the second opening. The valve seat assembly (2) is provided inside the valve body (1). The valve disc (4) is slidably provided at the end of the valve seat assembly (2) near the valve cover (7). The control assembly (3) is provided inside the valve seat assembly (2). The guide sleeve (6) is provided at the end of the valve disc (4) away from the valve seat assembly (2). The spring (5) is provided on the outside of the valve disc (4) and the guide sleeve (6). The bypass check valve (8) is provided inside the valve body (1) at the position of the third opening. The valve seat assembly (2), the control assembly (3), the valve disc (4), the spring (5), the guide sleeve (6), and the valve cover (7) are all coaxially arranged with the first opening and the second opening; The control component (3) includes: a valve push rod (31), a mounting head (32), a control head (33), an external thread (34), and a limiting hole (35); Wherein, one end of the valve push rod (31) is the control head (33) and the other end is the mounting head (32). The outer wall of the control head (33) is provided with the external thread (34), and the control head (33) is provided with the limiting hole (35) at the position of the external thread (34). The control head (33) is connected to the small valve disc assembly (9) via the external thread (34), and the mounting head (32) is disposed inside the valve disc (4) via the valve seat assembly (2) and abuts against the bottom of the inner hole of the valve disc (4) on the side near the valve seat assembly (2).

2. An inline trim automatic recirculation valve structure as defined in claim 1 wherein: The valve body (1) includes: a main passage (11), a bypass passage (12), a main inlet (13), a main outlet (14), and a bypass outlet (15). The valve body (1) is provided with a main passage (11) and a bypass passage (12). The main passage (11) and the bypass passage (12) are connected through the valve seat assembly (2). The first opening is connected to the main passage (11) through the main inlet (13). The second opening is connected to the main passage (11) through the main outlet (14). The third opening is connected to the bypass passage (12) through the bypass outlet (15).

3. An inline trim automatic recirculation valve structure as defined in claim 2 wherein: The valve seat assembly (2) includes: a bypass valve seat sleeve (21), a first flow passage (22), a connector (23), and a second flow passage (24); The bypass valve seat sleeve (21) has a hollow structure inside, with one end located inside the valve body (1) and the other end located inside the valve disc (4) via the connector (23). The bypass valve seat (21) has a first flow hole (22) at one end away from the valve disc (4), and the inside of the bypass valve seat (21) is connected to the main passage (11) through the first flow hole (22); The bypass valve seat (21) has a second flow hole (24) in the middle position, and the inside of the bypass valve seat (21) is connected to the bypass passage (12) through the second flow hole (24).

4. An inline trim automatic recirculation valve structure as defined in claim 3 wherein: The bypass valve seat (21) has multiple keyways (211) on its inner circumference.

5. An inline trim automatic recirculation valve structure as defined in claim 4 wherein: The control component (3) further includes: a spline (36); The valve push rod (31) has multiple splines (36) arranged around its outer circumference. Each spline (36) corresponds to a keyway (211). The valve push rod (31) is connected to the bypass valve seat sleeve (21) via the multiple splines (36).

6. An inline trim automatic recirculation valve structure as defined in claim 1 wherein: The small valve assembly (9) includes: a small valve (91), a self-made nut (92), an internal thread (93), and a plug groove (94); The small valve disc (91) is rotatably disposed on the outer wall of the control head (33), and the self-made nut (92) is provided with an internal thread (93) that mates with the external thread (34). The self-made nut (92) is threadedly connected to the control head (33) at the position of the external thread (34), and the small valve disc (91) is fixedly connected to the self-made nut (92). The small valve disc (91) is provided with the insertion groove (94).

7. An inline trim automatic recirculation valve structure as defined in claim 6 wherein: The insertion slot (94) and the limiting hole (35) are connected to a cotter pin (10) for limiting.

8. An inline trim automatic recirculation valve structure as defined in claim 1 wherein: The valve disc (4) is provided with a valve disc sealing surface (41), which coincides with the sealing surface of the valve body (1).

Images