Safety valve group structure and method for protecting two working conditions of overpressure and low pressure
By designing a safety valve assembly structure that includes elastic elements, automated control of overpressure and underpressure protection was achieved. This solved the problem that existing safety valve assemblies could not simultaneously handle two operating conditions, simplified circuit design, reduced costs, and improved equipment operating efficiency and safety.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHINA NUCLEAR POWER ENGINEERING COMPANY LTD
- Filing Date
- 2025-08-11
- Publication Date
- 2026-06-26
AI Technical Summary
Existing safety valve assemblies can only provide single overpressure or underpressure protection, and cannot handle both conditions simultaneously, resulting in increased system complexity, high cost, difficult maintenance, and low automation.
Design a safety valve assembly structure, including a pressure sensing circuit, a medium supply circuit, a main channel, a main valve switching passage, and a main valve. Utilize an elastic element to sense pressure changes and achieve overpressure and underpressure protection through an elastic orifice plate unit, a baffle unit, and a venting unit, simplifying circuit design.
It achieves automated control of overpressure and underpressure protection, reduces circuit length and volume, lowers manufacturing and maintenance costs, and improves equipment operating efficiency and safety.
Smart Images
Figure CN120906991B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of safety valves, specifically relating to a safety valve assembly structure and method for protecting against both overpressure and underpressure conditions. Background Technology
[0002] With the rapid development of industrial technology, the safety and reliability of pressure control systems have become a key focus across various industries. Safety valve assemblies, as crucial pressure protection equipment, are widely used in petrochemical, power, metallurgical, pharmaceutical, and food processing industries to prevent accidents caused by excessively high or low pressure. The performance of safety valve assemblies directly affects the stable operation and safety of the entire system.
[0003] Traditional safety valve assemblies typically only provide either overpressure or underpressure protection, failing to handle both conditions simultaneously. For example, in an overpressure situation, the valve automatically opens to release excess pressure, but in a underpressure situation, it cannot effectively replenish the medium or prevent further pressure drop. This limitation of a single function necessitates the configuration of multiple valve sets in practical applications, each dedicated to overpressure and underpressure protection. This not only increases system complexity but also significantly raises equipment costs and maintenance difficulties. Furthermore, installing multiple valve sets requires more space and more complex piping layouts, further increasing system design complexity and the risk of failure.
[0004] Most existing safety valve assemblies rely on manual control or complex mechanical structures for pressure regulation, resulting in low automation and susceptibility to failure. For example, some assemblies use external control components such as solenoid valves, which, while simplifying design and reducing size to some extent, also lowers system autonomy and reliability. Solenoid valves require external power and control systems; in the event of a power outage or abnormal control signal, the valve may malfunction, leading to uncontrolled system pressure. Furthermore, the complex mechanical structure results in high manufacturing and maintenance costs, and cumbersome troubleshooting and repair processes, impacting overall equipment efficiency. On the other hand, existing safety valve assemblies have limitations in their structural design. Many assemblies employ redundant loops and complex piping layouts, which, while achieving certain functions, increase system complexity and failure rates. For instance, some assemblies use multiple independent control loops for pressure regulation, but the lack of effective coordination between these loops easily leads to slow response and low regulation accuracy. Moreover, complex piping designs not only increase manufacturing costs but also make equipment installation and maintenance difficult, especially in space-constrained industrial settings.
[0005] Therefore, there is an urgent need to develop a safety valve assembly structure that integrates overpressure protection and underpressure protection, and is also capable of fully autonomous pressure control and pipeline venting. Summary of the Invention
[0006] The purpose of this invention is to overcome the shortcomings of the prior art and to provide a safety valve assembly structure and method for protecting against both overpressure and low pressure conditions.
[0007] The specific technical solution adopted in this invention is as follows:
[0008] In a first aspect, the present invention provides a safety valve assembly structure for protection under both overpressure and underpressure conditions, comprising a pressure sensing circuit, a medium supply circuit, a main channel, a main valve switching passage, and a main valve; the main valve is disposed between the main channel and the main valve switching passage, and the main valve core inside the main valve can move up and down; the main valve is provided with a discharge outlet; the main channel is connected to the pipeline system to be protected, and one side of the outlet of the main channel is connected to the pressure sensing circuit, and the other side is connected to the medium supply circuit;
[0009] A venting unit is provided at the connection between the pressure sensing circuit and the main valve switching passage, and a medium outlet is provided on the main valve switching passage; the venting unit controls the medium in the main valve switching passage to be cut off or to flow out from the medium outlet; a cut-off unit is provided in the medium supply circuit to control the flow direction of the medium in the medium supply circuit.
[0010] Preferably, the upper end area of the main valve core in the main valve is larger than the lower end area; under normal pressure, the lower end of the main valve core abuts against the main channel to prevent the medium in the main channel from flowing out from the vent outlet; under overpressure or low pressure conditions, the lower end of the main valve core moves upward, and the medium in the main channel flows out from the vent outlet.
[0011] Preferably, the venting unit includes a column, a third elastic element, and a third pipe extension section. The column has an upper through hole and a lower through hole. The height of the upper through hole, the lower through hole, and the middle part of the column without holes are all greater than the pipe diameter of the main valve switching passage. The third elastic element is fixed between the top of the column and the third pipe extension section, and the column can be adjusted up and down according to the pressure.
[0012] Furthermore, the shut-off unit includes a first elastic element, a first pipe extension section, a first fixed orifice plate, a second fixed orifice plate, and a movable orifice plate; the first fixed orifice plate and the second fixed orifice plate are fixedly spaced in the pipe of the medium supply circuit, and the movable orifice plate is disposed between the first fixed orifice plate and the second fixed orifice plate and can move along the pipe direction of the medium supply circuit; the first elastic element passes through the first fixed orifice plate and is fixed between the first pipe extension section and the movable orifice plate; under normal pressure conditions, the medium in the medium supply circuit passes through the shut-off unit and enters the main valve switching passage; under overpressure or low pressure conditions, the medium in the medium supply circuit does not enter the main valve switching passage.
[0013] Furthermore, both the upper and lower surfaces of the movable orifice plate are provided with protruding structures, and several through holes for the flow of medium are opened around the periphery of the protruding structures; the second fixed orifice plate is provided with through holes that fit with the protruding structures on the lower surface of the movable orifice plate; the first fixed orifice plate is also provided with through holes in the middle that fit with the protruding structures on the upper surface of the movable orifice plate, and the first elastic element passes through the through hole in the middle of the first fixed orifice plate and connects with the movable orifice plate.
[0014] Furthermore, the lower surface of the first fixing plate and the upper surface of the second fixing plate are provided with raised structures that fit with the through holes on the moving plate to improve sealing.
[0015] Furthermore, the medium supply circuit is divided into a horizontal pipe and a vertical pipe. The shut-off unit includes an elastic baffle unit disposed at the junction of the horizontal and vertical pipes and an elastic orifice plate unit disposed at the junction of the vertical pipe and the main valve switch passage. The elastic baffle unit includes a second elastic element, a baffle, and a second pipe extension. The baffle is coaxially disposed in the horizontal pipe of the medium supply circuit. The second elastic element is fixed between the baffle and the second pipe extension, allowing the second elastic element to move within the horizontal pipe of the medium supply circuit.
[0016] The elastic orifice plate unit includes a first elastic element, a fixed orifice plate, a movable orifice plate, and a first pipe extension section; the fixed orifice plate is fixed in the vertical pipe of the medium supply circuit, and a through hole is opened in the middle of the fixed orifice plate; the first elastic element passes through the through hole in the middle of the fixed orifice plate and is fixed between the movable orifice plate and the first pipe extension section.
[0017] Furthermore, the upper surface of the movable orifice plate is provided with a protruding structure that matches the through hole in the middle of the fixed orifice plate, and several through holes for the flow of medium are opened around the periphery of the protruding structure; the lower surface of the fixed orifice plate is also provided with a protruding structure that matches the through hole on the movable orifice plate, thereby improving the sealing performance.
[0018] Secondly, the present invention provides a method for protecting against both overpressure and underpressure conditions using the safety valve assembly structure described in the first aspect, as detailed below:
[0019] S1: Under normal main channel pressure, the third elastic element in the venting unit is in its natural state, and the un-holeed part of the column is between the main valve switching passage and the medium outlet. The medium in the main valve switching passage is not released; the lower end of the main valve core abuts against the main channel, and the main valve is in the closed state; the first elastic element is in its natural state, and the medium in the main channel enters the main valve switching passage through the through holes of the second fixed orifice plate, the movable orifice plate, and the first fixed orifice plate in sequence;
[0020] S2: When the main channel pressure is too low, the third elastic element in the venting unit is in a stretched state, and the column moves down so that the upper through hole is between the main valve switching passage and the medium outlet, and the medium in the main valve switching passage is released; after the medium in the main valve switching passage is released, the main valve core moves up and the lower end leaves the main channel, the main valve is in the open state, and the medium in the main channel flows out from the venting outlet; when the first elastic element is in a stretched state, the lower surface of the moving orifice plate abuts against the second fixed orifice plate, and the medium in the medium supply circuit does not enter the main valve switching passage;
[0021] S3: When the main channel pressure is too high, the third elastic element in the venting unit is in a compressed state, and the column moves upward so that the lower through hole is between the main valve switching passage and the medium outlet, and the medium in the main valve switching passage is released; after the medium in the main valve switching passage is released, the main valve core moves upward and the lower end leaves the main channel, the main valve is in the open state, and the medium in the main channel flows out from the venting outlet; the first elastic element is in a compressed state, the upper surface of the moving orifice plate abuts against the first fixed orifice plate, and the medium in the medium supply circuit does not enter the main valve switching passage.
[0022] Thirdly, the present invention provides a method for protecting against both overpressure and underpressure conditions using the safety valve assembly structure described in the first aspect, as detailed below:
[0023] S1: Under normal main channel pressure, the third elastic element in the venting unit is in its natural state, and the un-perforated part of the column is between the main valve switching passage and the medium outlet, so the medium in the main valve switching passage is not released; the lower end of the main valve core abuts against the main channel, and the main valve is in the closed state; the second elastic element in the elastic baffle unit is in the compressed state, and the baffle is located in the extension section of the second pipeline; the first elastic element in the elastic orifice plate unit is in its natural state, and the medium in the main channel enters the main valve switching passage through the through holes on the horizontal pipeline, vertical pipeline, moving orifice plate and fixed orifice plate of the medium supply circuit in sequence;
[0024] S2: When the main channel pressure is too low, the third elastic element in the venting unit is in a stretched state, and the column moves down so that the upper through hole is between the main valve switching passage and the medium outlet, and the medium in the main valve switching passage is released; after the medium in the main valve switching passage is released, the main valve core moves up and the lower end leaves the main channel, the main valve is in the open state, and the medium in the main channel flows out from the venting outlet; the second elastic element is in a stretched state, and the baffle prevents the medium in the horizontal pipe of the medium supply circuit from entering the vertical pipe;
[0025] S3: When the main channel pressure is too high, the third elastic element in the venting unit is in a compressed state, and the column moves upward so that the lower through hole is between the main valve switching passage and the medium outlet, and the medium in the main valve switching passage is released; after the medium in the main valve switching passage is released, the main valve core moves upward and the lower end leaves the main channel, the main valve is in the open state, and the medium in the main channel flows out from the venting outlet; the second elastic element is in a compressed state, the baffle is located in the second pipeline extension section, and the medium in the horizontal pipeline of the medium supply circuit enters the vertical pipeline; the first elastic element is in a compressed state, the upper surface of the moving orifice plate abuts against the fixed orifice plate, and the medium in the vertical pipeline of the medium supply circuit does not enter the main valve switching passage.
[0026] Compared with the prior art, the present invention has the following advantages:
[0027] Compared to the single protection function of existing safety valve assemblies, this invention uses a single safety valve assembly to achieve both overpressure and underpressure protection. This invention incorporates an elastic orifice plate unit, an elastic baffle unit, and a venting unit, all equipped with elastic elements. The elastic elements sense changes in the pressure of the medium in the pipeline, and when a pressure problem occurs, the main pipeline is vented.
[0028] This invention cleverly utilizes a movable elastic element to sense pressure changes, significantly reducing the length and volume of the circuit. Simultaneously, it automates the protection function without manual operation, greatly improving the equipment's operating efficiency and safety. Furthermore, the fewer components and simpler circuit design also reduce manufacturing and maintenance costs. Attached Figure Description
[0029] Figure 1 This is a schematic diagram of the safety valve assembly structure provided in Example 1;
[0030] Figure 2 This is a schematic diagram of the elastic perforated plate unit in Example 1;
[0031] Figure 3 This is a schematic diagram of the bleed-out unit in Example 1;
[0032] Figure 4 This is a schematic diagram of the elastic baffle unit in Example 1;
[0033] Figure 5 This is a schematic diagram of the fixing plate in Example 1;
[0034] Figure 6 This is a schematic diagram of the moving orifice plate in Example 1;
[0035] Figure 7 This is a schematic diagram of the baffle in Example 1;
[0036] Figure 8 This is a schematic diagram of the column in Example 1;
[0037] Figure 9 This is a schematic diagram of the cutoff unit in Example 2;
[0038] Figure 10 The medium distribution of the safety valve assembly under normal pressure conditions;
[0039] Figure 11 For the medium distribution of the safety valve assembly under low pressure conditions;
[0040] Figure 12 The medium distribution of the safety valve assembly under excessive pressure conditions;
[0041] Reference numerals in the attached diagram: 1. Pressure sensing circuit; 2. Medium supply circuit; 3. Main channel; 4. Main valve switch passage; 5. Main valve; 5-1. Main valve core; 6. Elastic orifice plate unit; 7. Elastic baffle unit; 8. Drainage unit; 9. Moving orifice plate; 10. Fixed orifice plate; 10-1. First fixed orifice plate; 10-2. Second fixed orifice plate; 11. Baffle; 12. Column; 12-1. Upper through hole; 12-2. Lower through hole; 13. Drainage outlet; 14. Medium outlet; 15. First pipeline extension Y1; 2. Second pipeline extension Y2; 3. Third pipeline extension Y3; 16. First elastic element T1; 2. Second elastic element T2; 3. Third elastic element T3. Detailed Implementation
[0042] The present invention will be further described and illustrated below with reference to the accompanying drawings and specific embodiments. The technical features of each embodiment of the present invention can be combined accordingly, provided that there is no mutual conflict.
[0043] Example 1
[0044] like Figure 1 As shown, in a preferred embodiment of the present invention, this embodiment provides a safety valve assembly structure for protection under both overpressure and underpressure conditions, including a pressure sensing circuit 1, a medium supply circuit 2, a main channel 3, a main valve switching passage 4, and a main valve 5. The main channel 3 is connected to the pipeline system to be protected, and one side of the outlet of the main channel 3 is connected to the pressure sensing circuit 1, while the other side is connected to the medium supply circuit 2.
[0045] The main valve 5 is located between the main channel 3 and the main valve switching passage 4. The main valve core 5-1 within the main valve 5 can move up and down. The main valve 5 has a relief outlet 13. The upper area of the main valve core 5-1 is larger than the lower area. When the main valve 5 is working normally, the main valve core 5-1 is closed due to the pressure difference. That is, under normal pressure, the lower end of the main valve core 5-1 presses against the main channel 3 to prevent the medium in the main channel 3 from flowing out of the relief outlet 13. Under overpressure or underpressure conditions, the lower end of the main valve core 5-1 moves upward, and the medium in the main channel 3 flows out of the relief outlet 13.
[0046] A venting unit 8 is provided at the connection between the pressure sensing circuit 1 and the main valve switching passage 4, and a medium outlet 14 is provided on the main valve switching passage 4. The venting unit 8 is located before the medium outlet 14 to control the medium in the main valve switching passage 4 to be cut off or to flow out from the medium outlet 14.
[0047] The bleed-out unit 8 provided in this embodiment is as follows: Figure 3 As shown. The venting unit 8 includes a column 12, a third elastic element T3, and a third pipe extension Y3. The third pipe extension Y3 is positioned along the extension direction of the pressure sensing circuit 1. An upper through-hole 12-1 and a lower through-hole 12-2 are provided on the column 12. The height of the upper through-hole 12-1, the lower through-hole 12-2, and the un-perforated middle section of the column 12 are all greater than the diameter of the main valve switching passage 4. The top of the column 12 and the third pipe extension Y3 are connected by the third elastic element T3. The third elastic element T3 adjusts the vertical movement of the column 12 according to the pressure of the medium in the pressure sensing circuit 1. When the upper through-hole 12-1 or the lower through-hole 12-2 is located between the main valve switching passage 4 and the medium outlet 14, the medium in the main valve switching passage 4 is released. When the unperforated portion of the column 12 is located between the main valve switching passage 4 and the medium outlet 14, the release of the medium in the main valve switching passage 4 is stopped.
[0048] The medium supply circuit 2 is equipped with a shut-off unit for controlling the flow direction of the medium within the circuit 2. In this embodiment, as shown... Figure 1 As shown, the medium supply circuit 2 is divided into a horizontal pipe and a vertical pipe. The shut-off unit includes an elastic baffle unit 7 installed at the connection between the horizontal pipe and the vertical pipe, and an elastic orifice plate unit 6 installed at the connection between the vertical pipe and the main valve switch passage 4.
[0049] like Figure 4 As shown, the elastic baffle unit 7 includes a second elastic element T2, a baffle 11, and a second pipe extension Y2. The second pipe extension Y2 is arranged in the extension direction of the horizontal pipe arrangement of the medium supply circuit 2. The baffle 11 provided in this embodiment is as follows: Figure 7 As shown. The diameter of the baffle 11 is approximately the same as the diameter of the horizontal pipe of the medium supply circuit 2, and the baffle 11 is coaxially disposed in the horizontal pipe of the medium supply circuit 2. The baffle 11 and the second pipe extension Y2 are connected by a second elastic element T2. The second elastic element T2 is controlled to move left and right in the horizontal pipe of the medium supply circuit 2 according to the pressure of the medium in the horizontal pipe of the medium supply circuit 2.
[0050] like Figure 2As shown, the elastic orifice plate unit 6 includes a first elastic element T1, a fixed orifice plate 10, a movable orifice plate 9, and a first pipe extension section Y1. The first pipe extension section Y1 is arranged in the extension direction of the vertical pipe arrangement of the medium supply circuit 2. The fixed orifice plate 10 is fixed in the vertical pipe of the medium supply circuit 2, and the movable orifice plate 9 is arranged below the fixed orifice plate 10.
[0051] The fixing plate 10 provided in this embodiment is as follows: Figure 5 As shown. A through hole is formed in the center of the fixed orifice plate 10. This through hole allows the first elastic element T1 to pass through, and the medium in the medium supply circuit 2 can also enter the main valve switching passage 4 through this through hole. The movable orifice plate 9 provided in this embodiment is as follows... Figure 6 As shown, the upper surface of the movable orifice plate 9 is provided with a protruding structure that matches the central through hole of the fixed orifice plate 10. Several through holes for the flow of the medium are formed around the periphery of the protruding structure. The first elastic element T1 passes through the central through hole of the fixed orifice plate 10 and is fixed between the protruding structure in the movable orifice plate 9 and the first pipe extension Y1. The lower surface of the fixed orifice plate 10 is also provided with a protruding structure that matches the upper through hole of the movable orifice plate 9. When the first elastic element T1 is in a compressed state, the lower surface of the fixed orifice plate 10 and the upper surface of the movable orifice plate 9 are in contact, which further improves the sealing performance.
[0052] This embodiment also provides a method for protecting against both overpressure and underpressure conditions using the above-described safety valve assembly structure, as detailed below:
[0053] (1) Under normal pressure conditions in the main channel 3, the third elastic element T3 in the relief unit 8 is in its natural state, and the un-perforated part of the column 12 is located between the main valve switching passage 4 and the medium outlet 14. The medium in the main valve switching passage 4 is not released. The lower end of the main valve core 5-1 abuts against the main channel 3, and the main valve 5 is in the closed state. The second elastic element T2 in the elastic baffle unit 7 is in the compressed state, and the baffle 11 is located in the second pipeline extension section Y2. The first elastic element T2 in the elastic orifice plate unit 6 is in its natural state, and there is still a distance between the moving orifice plate 9 and the fixed orifice plate 10 without contact. At this time, the medium supply circuit 2 and the main valve switching passage 4 are connected. The medium in the main channel 3 enters the main valve switching passage 4 sequentially through the horizontal pipe, vertical pipe, moving orifice plate 9, and through the holes on the fixed orifice plate 10 of the medium supply circuit 2. The medium distribution of the safety valve assembly under normal pressure conditions is as follows: Figure 10 As shown.
[0054] (2) When the pressure in the main channel 3 is too low, the third elastic element T3 in the relief unit 8 is in a stretched state, and the column 12 moves downward so that the upper through hole 12-1 is between the main valve switching passage 4 and the medium outlet 14, and the medium in the main valve switching passage 4 is released. After the medium in the main valve switching passage 4 is released, the medium in the main channel 3 pushes open the lower end of the main valve core 5-1, causing the main valve core 5-1 to move upward and the lower end to leave the main channel 3, and the main valve 5 is in the open state. The medium in the main channel 3 flows out from the relief outlet 13, which plays a role in low-pressure protection for the entire pipeline system. In this case, the second elastic element T2 is in a stretched state, and the baffle 11 prevents the medium in the horizontal pipeline of the medium supply circuit 2 from entering the vertical pipeline. The medium distribution of the safety valve group under the low pressure condition is as follows: Figure 11 As shown.
[0055] (3) When the pressure in the main channel 3 is too high, the third elastic element T3 in the relief unit 8 is in a compressed state, and the column 12 moves upward so that the lower through hole 12-2 is between the main valve switching passage 4 and the medium outlet 14, and the medium in the main valve switching passage 4 is released. After the medium in the main valve switching passage 4 is released, the medium in the main channel 3 pushes open the lower end of the main valve core 5-1, so that the main valve core 5-1 moves upward and the lower end leaves the main channel 3, the main valve 5 is in the open state, and the medium in the main channel 3 flows out from the relief outlet 13, which plays the role of overpressure protection for the entire pipeline system. In this case, the second elastic element T2 is in a compressed state, the baffle 11 is located in the second pipeline extension section Y2, and the medium in the horizontal pipeline of the medium supply circuit 2 enters the vertical pipeline. The first elastic element T1 is in a compressed state, the upper surface of the moving orifice plate 9 abuts against the fixed orifice plate 10, and the medium in the vertical pipeline of the medium supply circuit 2 does not enter the main valve switching passage 4. The medium distribution of the safety valve group under the high pressure condition is as follows Figure 12 As shown.
[0056] Example 2
[0057] As a preferred embodiment of the present invention, this embodiment provides a safety valve assembly structure for protection under both overpressure and underpressure conditions, including a pressure sensing circuit 1, a medium supply circuit 2, a main channel 3, a main valve switching passage 4, and a main valve 5. The main channel 3 is connected to the pipeline system to be protected, with one outlet side of the main channel 3 connected to the pressure sensing circuit 1 and the other side connected to the medium supply circuit 2.
[0058] The main valve 5 is located between the main channel 3 and the main valve switching passage 4. The main valve core 5-1 within the main valve 5 can move up and down. The main valve 5 has a relief outlet 13. The upper area of the main valve core 5-1 is larger than the lower area. When the main valve 5 is working normally, the main valve core 5-1 is closed due to the pressure difference. That is, under normal pressure, the lower end of the main valve core 5-1 presses against the main channel 3 to prevent the medium in the main channel 3 from flowing out of the relief outlet 13. Under overpressure or underpressure conditions, the lower end of the main valve core 5-1 moves upward, and the medium in the main channel 3 flows out of the relief outlet 13.
[0059] A venting unit 8 is provided at the connection between the pressure sensing circuit 1 and the main valve switching passage 4, and a medium outlet 14 is provided on the main valve switching passage 4. The venting unit 8 is located before the medium outlet 14 to control the medium in the main valve switching passage 4 to be cut off or to flow out from the medium outlet 14.
[0060] The difference between this embodiment and embodiment 1 is that the elastic baffle unit 7 and the elastic perforated plate unit 6 can be combined into a single unit module, as shown below. Figure 9 As shown. The cutoff unit includes a first elastic element T1, a first pipe extension Y1, a first fixed orifice plate 10-1, a second fixed orifice plate 10-2, and a movable orifice plate 9. The first fixed orifice plate 10-1 and the second fixed orifice plate 10-2 are fixedly spaced in the pipe of the medium supply circuit 2, and the movable orifice plate 9 is disposed between the first fixed orifice plate 10-1 and the second fixed orifice plate 10-2 and can move along the pipe direction of the medium supply circuit 2.
[0061] The movable orifice plate 9 provided in this embodiment has raised structures on both its upper and lower surfaces, with several through holes for the flow of the medium around the raised structures. A through hole is provided in the middle of the first fixed orifice plate 10-1, which matches the raised structure on the upper surface of the movable orifice plate 9. A through hole is also provided in the middle of the second fixed orifice plate 10-2, which matches the raised structure on the lower surface of the movable orifice plate 9. A first elastic element T1 passes through the through hole in the middle of the first fixed orifice plate 10-1 and connects to the raised structure on the upper surface of the movable orifice plate 9. The first elastic element T1 is positioned between the first pipe extension section Y1 and the movable orifice plate 9. Under normal pressure conditions, the medium in the medium supply circuit 2 passes through the shut-off unit and enters the main valve switching passage 4. Under overpressure or low pressure conditions, the medium in the medium supply circuit 2 does not enter the main valve switching passage 4. Furthermore, raised structures that match the through holes on the upper surface of the first fixed orifice plate 10-1 and the upper surface of the second fixed orifice plate 10-2 are also provided to improve sealing.
[0062] This embodiment also provides a method for protecting against both overpressure and underpressure conditions using the above-described safety valve assembly structure, as detailed below:
[0063] (1) Under normal pressure conditions in the main channel 3, the third elastic element T3 in the venting unit 8 is in its natural state, and the un-perforated part of the column 12 is located between the main valve switching passage 4 and the medium outlet 14. The medium in the main valve switching passage 4 is not released. The lower end of the main valve core 5-1 abuts against the main channel 3, and the main valve 5 is in the closed state. The first elastic element T1 is in its natural state, and the medium in the main channel 3 enters the main valve switching passage 4 through the through holes on the second fixed orifice plate 10-2, the movable orifice plate 9, and the first fixed orifice plate 10-1 in sequence.
[0064] (2) When the pressure in the main channel 3 is too low, the third elastic element T3 in the venting unit 8 is in a stretched state, and the column 12 moves downward so that the upper through hole 12-1 is between the main valve switching passage 4 and the medium outlet 14, and the medium in the main valve switching passage 4 is released. After the medium in the main valve switching passage 4 is released, the main valve core 5-1 moves upward, and the lower end leaves the main channel 3, the main valve 5 is in the open state, and the medium in the main channel 3 flows out from the venting outlet 13. The first elastic element T1 is in a stretched state, and the lower surface of the moving orifice plate 9 abuts against the second fixed orifice plate 10-2, so the medium in the medium supply circuit 2 does not enter the main valve switching passage 4.
[0065] (3) When the pressure in the main channel 3 is too high, the third elastic element T3 in the venting unit 8 is in a compressed state, and the column 12 moves upward so that the lower through hole 12-2 is between the main valve switching passage 4 and the medium outlet 14, and the medium in the main valve switching passage 4 is released. After the medium in the main valve switching passage 4 is released, the main valve core 5-1 moves upward and the lower end leaves the main channel 3, the main valve 5 is in the open state, and the medium in the main channel 3 flows out from the venting outlet 13. The first elastic element T1 is in a compressed state, and the upper surface of the moving orifice plate 9 abuts against the first fixed orifice plate 10-1, so the medium in the medium supply circuit 2 does not enter the main valve switching passage 4.
[0066] In the above embodiments, the first elastic element T1, the second elastic element T2, and the third elastic element T3 are all springs. The terms "normal pressure," "too low pressure," and "too high pressure" refer to actual operating conditions; this embodiment does not specifically limit the pressure threshold. Those skilled in the art can set the pressure threshold according to the specific conditions of the pipeline system to be protected, connected to the safety valve assembly structure. Correspondingly, those skilled in the art can also select a spring of appropriate strength based on the threshold value to achieve the above functions.
[0067] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the invention. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention. Therefore, all technical solutions obtained through equivalent substitution or transformation fall within the protection scope of the present invention.
Claims
1. A safety valve assembly structure for protection under both overpressure and underpressure conditions, characterized in that, It includes a pressure sensing circuit (1), a medium supply circuit (2), a main channel (3), a main valve switching passage (4), and a main valve (5); the main valve (5) is located between the main channel (3) and the main valve switching passage (4), and the main valve core (5-1) inside the main valve (5) can move up and down; the main valve (5) is provided with a discharge outlet (13); the main channel (3) is connected to the pipeline system to be protected, and one side of the outlet of the main channel (3) is connected to the pressure sensing circuit (1), and the other side is connected to the medium supply circuit (2); A venting unit (8) is provided at the connection between the pressure sensing circuit (1) and the main valve switching passage (4), and a medium outlet (14) is provided on the main valve switching passage (4); the venting unit (8) controls the medium in the main valve switching passage (4) to be cut off or to flow out from the medium outlet (14); the medium supply circuit (2) is provided with a cut-off unit for controlling the flow direction of the medium in the medium supply circuit (2); The upper area of the main valve core (5-1) in the main valve (5) is larger than the lower area. Under normal pressure, the lower end of the main valve core (5-1) abuts against the main channel (3) to prevent the medium in the main channel (3) from flowing out from the discharge outlet (13). Under overpressure or low pressure, the lower end of the main valve core (5-1) moves upward and the medium in the main channel (3) flows out from the discharge outlet (13). The venting unit (8) includes a column (12), a third elastic element (T3), and a third pipe extension (Y3). The column (12) has an upper through hole (12-1) and a lower through hole (12-2). The height of the upper through hole (12-1), the lower through hole (12-2), and the middle part of the column (12) without holes is greater than the pipe diameter of the main valve switching passage (4). The third elastic element (T3) is fixed between the top of the column (12) and the third pipe extension (Y3), and the column (12) can be adjusted up and down according to the pressure. The shut-off unit includes a first elastic element (T1), a first pipe extension section (Y1), a first fixed orifice plate (10-1), a second fixed orifice plate (10-2), and a movable orifice plate (9); the first fixed orifice plate (10-1) and the second fixed orifice plate (10-2) are fixed at intervals in the pipe of the medium supply circuit (2), and the movable orifice plate (9) is disposed between the first fixed orifice plate (10-1) and the second fixed orifice plate (10-2) and can move along the pipe direction of the medium supply circuit (2); the first elastic element (T1) passes through the first fixed orifice plate (10-1) and is fixed between the first pipe extension section (Y1) and the movable orifice plate (9); under normal pressure, the medium in the medium supply circuit (2) passes through the shut-off unit and enters the main valve switching passage (4); under overpressure or low pressure conditions, the medium in the medium supply circuit (2) does not enter the main valve switching passage (4).
2. The safety valve assembly structure according to claim 1, characterized in that, The upper and lower surfaces of the movable orifice plate (9) are provided with protruding structures, and several through holes for the flow medium are opened around the periphery of the protruding structures; the second fixed orifice plate (10-2) is provided with through holes that fit with the protruding structures on the lower surface of the movable orifice plate (9); the middle of the first fixed orifice plate (10-1) is also provided with through holes that fit with the protruding structures on the upper surface of the movable orifice plate (9), and the first elastic member (T1) passes through the through hole in the middle of the first fixed orifice plate (10-1) and connects with the movable orifice plate (9).
3. The safety valve assembly structure according to claim 2, characterized in that, The lower surface of the first fixed hole plate (10-1) and the upper surface of the second fixed hole plate (10-2) are also provided with protruding structures that fit with the through holes on the movable hole plate (9) to improve sealing.
4. The safety valve assembly structure according to claim 1, characterized in that, The medium supply circuit (2) is divided into a horizontal pipe and a vertical pipe. The shut-off unit includes an elastic baffle unit (7) set at the connection between the horizontal pipe and the vertical pipe and an elastic orifice plate unit (6) set at the connection between the vertical pipe and the main valve switch passage (4). The elastic baffle unit (7) includes a second elastic element (T2), a baffle (11), and a second pipe extension section (Y2). The baffle (11) is coaxially set in the horizontal pipe of the medium supply circuit (2). The second elastic element (T2) is fixed between the baffle (11) and the second pipe extension section (Y2), so that the second elastic element (T2) can move in the horizontal pipe of the medium supply circuit (2). The elastic orifice plate unit (6) includes a first elastic element (T1), a fixed orifice plate (10), a movable orifice plate (9), and a first pipe extension section (Y1); the fixed orifice plate (10) is fixed in the vertical pipe of the medium supply circuit (2), and a through hole is opened in the middle of the fixed orifice plate (10); the first elastic element (T1) passes through the through hole in the middle of the fixed orifice plate (10) and is fixed between the movable orifice plate (9) and the first pipe extension section (Y1).
5. The safety valve assembly structure according to claim 4, characterized in that, The upper surface of the movable orifice plate (9) is provided with a protruding structure that matches the through hole in the middle of the fixed orifice plate (10), and several through holes for the flow of medium are opened around the protruding structure; the lower surface of the fixed orifice plate (10) is also provided with a protruding structure that matches the through hole on the movable orifice plate (9) to improve the sealing performance.
6. A method for providing overpressure and underpressure protection using the safety valve assembly structure described in any one of claims 1 to 3, as detailed below: S1: Under normal pressure conditions in the main channel (3), the third elastic element (T3) in the venting unit (8) is in its natural state, and the unopened part of the column (12) is between the main valve switching passage (4) and the medium outlet (14), so the medium in the main valve switching passage (4) is not released; the lower end of the main valve core (5-1) abuts against the main channel (3), and the main valve (5) is in the closed state; the first elastic element (T1) is in its natural state, and the medium in the main channel (3) enters the main valve switching passage (4) through the through holes on the second fixed orifice plate (10-2), the moving orifice plate (9), and the first fixed orifice plate (10-1) in sequence; S2: When the pressure in the main channel (3) is too low, the third elastic element (T3) in the venting unit (8) is in a stretched state, and the column (12) moves down so that the upper through hole (12-1) is between the main valve switching passage (4) and the medium outlet (14), and the medium in the main valve switching passage (4) is released; after the medium in the main valve switching passage (4) is released, the main valve core (5-1) moves up and the lower end leaves the main channel (3), the main valve (5) is in an open state, and the medium in the main channel (3) flows out from the venting outlet (13); the first elastic element (T1) is in a stretched state, and the lower surface of the moving orifice plate (9) abuts against the second fixed orifice plate (10-2), and the medium in the medium supply circuit (2) does not enter the main valve switching passage (4); S3: When the pressure in the main channel (3) is too high, the third elastic element (T3) in the venting unit (8) is in a compressed state, and the column (12) moves up so that the lower through hole (12-2) is between the main valve switching passage (4) and the medium outlet (14), and the medium in the main valve switching passage (4) is released; after the medium in the main valve switching passage (4) is released, the main valve core (5-1) moves up and the lower end leaves the main channel (3), the main valve (5) is in an open state, and the medium in the main channel (3) flows out from the venting outlet (13); the first elastic element (T1) is in a compressed state, and the upper surface of the moving orifice plate (9) abuts against the first fixed orifice plate (10-1), and the medium in the medium supply circuit (2) does not enter the main valve switching passage (4).
7. A method for providing overpressure and underpressure protection using the safety valve assembly structure described in claim 4 or 5, specifically as follows: S1: Under normal pressure conditions in the main channel (3), the third elastic element (T3) in the venting unit (8) is in a natural state, and the unopened part of the column (12) is between the main valve switching passage (4) and the medium outlet (14), so the medium in the main valve switching passage (4) is not released; the lower end of the main valve core (5-1) abuts against the main channel (3), and the main valve (5) is in a closed state; the second elastic element (T2) in the elastic baffle unit (7) is in a compressed state, and the baffle (11) is located in the second pipeline extension section (Y2); the first elastic element (T1) in the elastic orifice plate unit (6) is in a natural state, and the medium in the main channel (3) enters the main valve switching passage (4) in sequence through the horizontal pipe, vertical pipe, moving orifice plate (9) and fixed orifice plate (10) of the medium supply circuit (2); S2: When the pressure in the main channel (3) is too low, the third elastic element (T3) in the venting unit (8) is in a stretched state, and the column (12) moves down so that the upper through hole (12-1) is between the main valve switching passage (4) and the medium outlet (14), and the medium in the main valve switching passage (4) is released; after the medium in the main valve switching passage (4) is released, the main valve core (5-1) moves up and the lower end leaves the main channel (3), the main valve (5) is in an open state, and the medium in the main channel (3) flows out from the venting outlet (13); the second elastic element (T2) is in a stretched state, and the baffle (11) prevents the medium in the horizontal pipe of the medium supply circuit (2) from entering the vertical pipe; S3: When the pressure in the main channel (3) is too high, the third elastic element (T3) in the venting unit (8) is in a compressed state, the column (12) moves up so that the lower through hole (12-2) is between the main valve switching passage (4) and the medium outlet (14), and the medium in the main valve switching passage (4) is released; after the medium in the main valve switching passage (4) is released, the main valve core (5-1) moves up and the lower end leaves the main channel (3), the main valve (5) is in an open state, and the medium in the main channel (3) flows out from the venting outlet (13); the second elastic element (T2) is in a compressed state, the baffle (11) is located in the second pipeline extension section (Y2), and the medium in the horizontal pipeline of the medium supply circuit (2) enters the vertical pipeline; the first elastic element (T1) is in a compressed state, the upper surface of the moving orifice plate (9) abuts against the fixed orifice plate (10), and the medium in the vertical pipeline of the medium supply circuit (2) does not enter the main valve switching passage (4).