Safety class quick closing isolation valve for nuclear power plant

Abstract

This invention relates to the field of isolation valve technology for nuclear power plants, and particularly to a safety-grade fast-sealing isolation valve for nuclear power plants. A safety-grade fast-sealing isolation valve for nuclear power plants includes a valve body, a linkage mechanism, a drive mechanism, multiple rotating rod assemblies, multiple sealing end cap assemblies, multiple rotating shafts, and multiple discs. The sealing end cap assemblies are disposed on the valve body, and the rotating shafts are rotatably connected to the valve body and the corresponding sealing end cap assemblies. Each sealing end cap assembly includes a sealing ring for sealing the connection between the rotating shaft and the sealing end cap assembly. This safety-grade fast-sealing isolation valve for nuclear power plants possesses more effective and reliable sealing performance, a compact overall structure, and strong stability, solving the problems of poor sealing performance and poor operational stability of existing isolation valves for nuclear power plants.

Description

Technical Field

[0001] This invention relates to the field of isolation valve technology for nuclear power plants, and more particularly to a safety-grade fast-sealing isolation valve for nuclear power plants. Background Technology

[0002] In nuclear power plants, isolation valves are used in safety-related ventilation systems to isolate airflow. They are typically installed at the inlet of the supply or exhaust fan and can be remotely controlled or manually operated. Existing isolation valves suffer from poor sealing at the shaft that drives the disc rotation, leading to external leakage. Furthermore, the sealing strip's fit with the valve body is poor, making it prone to detachment and resulting in poor sealing performance. Current isolation valves primarily use spring-assisted disc opening, which increases the probability of malfunctions during severe environmental events such as earthquakes, leading to poor operational stability. Summary of the Invention

[0003] In response to the problems raised in the background art, the purpose of this invention is to provide a safety-grade fast-sealing isolation valve for nuclear power plants. This safety-grade fast-sealing isolation valve for nuclear power plants has more effective and reliable sealing performance, a compact overall structure, and strong stability, thus solving the problems of poor sealing performance and poor operational stability of existing isolation valves for nuclear power plants.

[0004] To achieve this objective, the present invention adopts the following technical solution:

[0005] A safety-grade fast-sealing isolation valve for nuclear power plants includes a valve body, a linkage mechanism, a drive mechanism, multiple rotating rod assemblies, multiple sealing end cap assemblies, multiple rotating shafts, and multiple discs.

[0006] The sealing end cap assembly is disposed on the valve body, and the rotating shaft is rotatably connected to the valve body and the corresponding sealing end cap assembly. The sealing end cap assembly includes a sealing ring, which is used to seal the connection between the rotating shaft and the sealing end cap assembly.

[0007] Multiple rotating shafts are arranged vertically at intervals on the valve body. The disc is connected to the valve body and the corresponding rotating shaft through the rotating rod assembly. The multiple rotating shafts are respectively connected to the linkage mechanism. The output end of the drive mechanism is connected to the linkage mechanism. The drive mechanism drives the rotating shaft to rotate through the linkage mechanism. The rotation of the rotating shaft drives the corresponding disc to rotate, thereby realizing the opening and closing of the disc.

[0008] The valve body is provided with a valve seat and a plurality of limiting blocks. A sealing strip is fastened inside the valve seat. When the disc is closed, both ends of the disc abut against the sealing strip. The limiting blocks are arranged one-to-one with the discs and are located in front of the corresponding discs. When the disc is open, the upper surface of the disc abuts against the lower end of the limiting block, and the disc is in a horizontally open state.

[0009] To further explain, the valve body includes a side frame and a connecting frame. The side frames are spaced apart and symmetrically arranged. The connecting frame is disposed between the two side frames and is connected to the upper and lower ends of the side frames.

[0010] The valve seat is disposed between the two side frames and is connected to the rear of the side frames. The limiting block is disposed at the front of the side frames, and the disc is located between the valve seat and the limiting block.

[0011] Furthermore, the sealing end cap assembly also includes a bearing cap and a pressure plate. The bearing cap and the pressure plate are both hollow structures. A bearing is embedded at one end of the bearing cap, and the inner wall of the other end of the bearing cap has an internal thread. The outer circumference of the pressure plate has an external thread, and the external thread of the pressure plate is threadedly engaged with the internal thread of the bearing cap. A spacer is provided on the inner wall of the bearing cap, and the spacer is disposed between the internal thread and the bearing. The inner ring of the bearing is connected to the rotating shaft, and the outer ring of the bearing is connected to the bearing cap. The sealing ring is pressed between the pressure plate and the spacer.

[0012] The outer side wall of the side frame is provided with multiple bases at intervals, and the bearing cover is connected to the corresponding base.

[0013] To further explain, the limiting block is cam-shaped, and the inner wall of the side frame is provided with multiple limiting bolts. The limiting block is detachably installed on the corresponding limiting bolt.

[0014] Furthermore, the valve body also includes a positioning arm and a hollow auxiliary tube. The side frame is provided with multiple positioning holes. One end of the auxiliary tube is fixedly connected to the corresponding positioning hole, and the other end of the auxiliary tube is fixedly connected to the positioning arm. The rotating shaft passes through the auxiliary tube and the positioning hole and is rotatably connected to the side frame.

[0015] The disc is connected to the positioning arm and the corresponding rotating shaft via the rotary rod assembly.

[0016] To further explain, the disc plate includes blades, a first spiral arm, and a second spiral arm;

[0017] The first rotating arm is disposed between the two second rotating arms, and the first rotating arm and the second rotating arm are arranged along the length direction of the disc. The positioning arm is provided with a first pin, and the second rotating arm is provided with a second pin.

[0018] The rotating rod assembly includes an inner rotating arm and an inner connecting rod. One end of the inner rotating arm is fixedly connected to the corresponding rotating shaft, and the other end of the inner rotating arm is connected to the first rotating arm via a pin. One end of the inner connecting rod is connected to the first pin, and the other end of the inner connecting rod is connected to the second pin.

[0019] To further explain, the linkage mechanism includes a connecting rod and a plurality of first external rotating arms. One end of the first external rotating arm is fixedly connected to the corresponding rotating shaft, and the other end of the first external rotating arm is connected to the connecting rod via a pin. The output end of the drive mechanism is connected to the connecting rod.

[0020] To further explain, the drive mechanism includes a bracket and a drive device, and the linkage mechanism also includes a second external rotating arm. The bracket is fixedly installed on the valve body, the drive device is installed on the bracket, the output shaft of the drive device is fixedly connected to one end of the second external rotating arm, and the other end of the second external rotating arm is connected to the linkage.

[0021] To further explain, the side of the sealing strip facing the disc is wavy or toothed.

[0022] To further explain, the sealing strip has a groove on the side that fits against the valve seat, and the valve seat has an inner boss that mates with the groove on its inner side, and the inner boss is fastened into the groove.

[0023] Alternatively, the sealing strip may have grooves at its upper and lower ends, and the valve seat may have a C-shaped structure and be fitted into the grooves.

[0024] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0025] The aforementioned safety-grade fast-sealing isolation valve for nuclear power plants has more effective and reliable sealing performance, a compact overall structure, and strong stability, solving the problems of poor sealing performance and poor operational stability of existing isolation valves for nuclear power plants. Attached Figure Description

[0026] Figure 1 This is a three-dimensional structural diagram of a safety-grade fast-closing isolation valve for nuclear power plants according to an embodiment of the present invention (the disc is in the open state);

[0027] Figure 2 This is a three-dimensional structural schematic diagram of a safety-grade fast-closing isolation valve for nuclear power plants according to an embodiment of the present invention (the disc is in the closed state);

[0028] Figure 3 This is a three-dimensional structural diagram of the valve body of a safety-grade fast-closing isolation valve for nuclear power plants according to an embodiment of the present invention;

[0029] Figure 4 This is a cross-sectional view of the connecting frame of the valve body of a safety-grade fast-closing isolation valve for nuclear power plants according to an embodiment of the present invention.

[0030] Figure 5 This is a front view of the valve body of a safety-grade fast-closing isolation valve for nuclear power plants according to an embodiment of the present invention;

[0031] Figure 6 This is a left view of the valve body of a safety-grade fast-closing isolation valve for nuclear power plants according to an embodiment of the present invention;

[0032] Figure 7 yes Figure 5 AA section diagram;

[0033] Figure 8 yes Figure 5 BB cross-section diagram (disc is in the closed state);

[0034] Figure 9 yes Figure 5 BB cross-section diagram (disc plate in open state);

[0035] Figure 10 yes Figure 7 Enlarged structural diagram at point D;

[0036] Figure 11 yes Figure 5 CC section view;

[0037] Figure 12 This is a schematic diagram of the linkage mechanism and rotating shaft installation structure of a safety-grade fast-closing isolation valve for nuclear power plants according to an embodiment of the present invention;

[0038] Figure 13 This is a schematic diagram of the installation structure of the limit block and auxiliary pipe of a safety-grade fast-closing isolation valve for nuclear power plants according to an embodiment of the present invention;

[0039] Figure 14 This is a schematic diagram of the installation structure of the limit block and auxiliary pipe of a safety-grade fast-closing isolation valve for nuclear power plants according to an embodiment of the present invention;

[0040] Figure 15 This is a schematic diagram of the structure of the limiting block of a safety-grade fast-closing isolation valve for nuclear power plants according to an embodiment of the present invention;

[0041] Figure 16This is a schematic diagram of the positioning hole of the side frame of the valve body of a safety-grade fast-sealing isolation valve for nuclear power plants according to an embodiment of the present invention;

[0042] Figure 17 This is a schematic diagram of the disc plate of a safety-grade fast-closing isolation valve for nuclear power plants according to an embodiment of the present invention;

[0043] Figure 18 This is a schematic diagram of the blade structure of the disc plate of a safety-grade fast-closing isolation valve for nuclear power plants according to an embodiment of the present invention;

[0044] Figure 19 This is a schematic diagram of the installation structure of the valve seat and sealing strip of the disc plate of a safety-grade fast-closing isolation valve for nuclear power plants according to an embodiment of the present invention.

[0045] Figure 20 This is a cross-sectional view of the valve seat of the valve body of a safety-grade fast-closing isolation valve for nuclear power plants according to an embodiment of the present invention;

[0046] Figure 21 This is a cross-sectional view of the sealing strip of a safety-grade fast-closing isolation valve for nuclear power plants according to an embodiment of the present invention;

[0047] Figure 22 This is a cross-sectional view of the valve seat of the valve body of a safety-grade fast-closing isolation valve for nuclear power plants according to another embodiment of the present invention;

[0048] Figure 23 This is a cross-sectional view of the valve seat of the valve body of a safety-grade fast-closing isolation valve for nuclear power plants according to another embodiment of the present invention;

[0049] Figure 24 This is a cross-sectional view of the sealing strip of a safety-grade fast-closing isolation valve for nuclear power plants according to another embodiment of the present invention;

[0050] Figure 25 This is a cross-sectional view of the sealing strip of a safety-grade fast-closing isolation valve for nuclear power plants according to another embodiment of the present invention;

[0051] In the attached diagram: valve body 1, valve seat 11, inner boss 111, reinforcing plate 112, limiting block 12, sealing strip 13, groove 131, slot 132, side frame 14, base 141, limiting bolt 142, positioning hole 143, connecting frame 15, positioning arm 16, first pin 161, auxiliary tube 17, linkage mechanism 2, connecting rod 21, first outer rotating arm 22, second outer rotating arm 23, drive mechanism 3, bracket 31, drive device 32, rotating rod assembly 4, inner rotating arm 41, inner connecting rod 42, sealing end cover assembly 5, sealing ring 51, bearing cover 52, bearing 521, spacer 522, pressure plate 53, rotating shaft 6, disc 7, blade 71, first rotating arm 72, second rotating arm 73, second pin 731. Detailed Implementation

[0052] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0053] In the description of this invention, it should be understood that the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "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 the invention and for simplifying the description, and do not indicate or imply that the device or element 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 the invention. Furthermore, features defined with "first" and "second" may explicitly or implicitly include one or more of these features, used to distinguish and describe features, without any order or emphasis.

[0054] In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0055] like Figures 1 to 25 As shown, a safety-grade fast-sealing isolation valve for nuclear power plants includes a valve body 1, a linkage mechanism 2, a drive mechanism 3, multiple rotating rod assemblies 4, multiple sealing end cap assemblies 5, multiple rotating shafts 6, and multiple discs 7.

[0056] The sealing end cap assembly 5 is disposed on the valve body 1, and the rotating shaft 6 is rotatably connected to the valve body 1 and the corresponding sealing end cap assembly 5. The sealing end cap assembly 5 includes a sealing ring 51, which is used to seal the connection between the rotating shaft 6 and the sealing end cap assembly 5.

[0057] Multiple rotating shafts 6 are arranged vertically at intervals on the valve body 1. The disc 7 is connected to the valve body 1 and the corresponding rotating shaft 6 through the rotating rod assembly 4. The multiple rotating shafts 6 are respectively connected to the linkage mechanism 2 for transmission. The output end of the drive mechanism 3 is connected to the linkage mechanism 2. The drive mechanism 3 drives the rotating shaft 6 to rotate through the linkage mechanism 2. The rotation of the rotating shaft 6 drives the corresponding disc 7 to rotate, thereby realizing the opening and closing of the disc 7.

[0058] The valve body 1 is provided with a valve seat 11 and a plurality of limiting blocks 12. A sealing strip 13 is fastened inside the valve seat 11. When the disc 7 is closed, both ends of the disc 7 abut against the sealing strip 13 respectively. The limiting blocks 12 are arranged one-to-one with the disc 7, and the limiting blocks 12 are arranged in front of the corresponding disc 7. When the disc 7 is open, the upper end surface of the disc 7 abuts against the lower end of the limiting block 12, and the disc 7 is in a horizontally open state.

[0059] By setting the sealing end cap assembly 5, the sealing ring 51 is used to seal the connection between the rotating shaft 6 and the sealing end cap assembly 5, which can prevent radioactive gas from seeping out from the shaft end, and the sealing effect is good. In addition, by using a tight-fitting method between the valve seat 11 and the sealing strip 13, even if the butterfly plate 7 and the sealing strip 13 "seep in" into each other, the butterfly plate 7 will not pull the sealing strip 13 off the valve seat 11 when it is opened, thereby ensuring that the safety-grade fast-closing isolation valve for nuclear power plants will not have internal leakage, and the sealing effect is good, meeting the safety requirements for use.

[0060] Currently, in operating nuclear power plants, some isolation valves are limited in length to 180mm-185mm due to installation space constraints. Given the requirement for near-zero internal leakage and a small flow resistance coefficient, shortening the structural length using existing products necessitates increasing the number of blades (spring-assisted butterfly valves require double limit switches positioned in the middle of the blades; shorter valve bodies require narrower blades for double limit switches, thus increasing the blade count), leading to a corresponding increase in pressure loss. Therefore, existing isolation valves with ≥250mm diameter and double limit switches cannot be used. This invention, by incorporating the connecting rod mechanism 2, the rotating rod assembly 4, and the limit block 12, enables the opening and closing of the butterfly plate 7 even with a shorter valve body 1 and a wider butterfly plate 7 (fewer butterfly plates result in lower pressure loss). Figure 2 As shown, for valve body 1, the front-to-back direction indicated in the figure is the length direction of valve body 1, the left-to-right direction indicated in the figure is the width direction of valve body 1, and the up-down direction indicated in the figure is the height direction of valve body 1; for disc 7, the left-to-right direction indicated in the figure is the length direction of disc 7, and the up-down direction indicated in the figure is the width direction of disc 7. This solves the problem of excessively long installation of isolation valves in existing operating nuclear power plants and can reduce the number of disc 7, reduce pressure loss, effectively reduce the energy consumption of the ventilation system, and save the operating cost of nuclear power plants.

[0061] By setting the limiting block 12, it can be ensured that the disc 7 is in a horizontally open state when opened, and that the upper end of the disc 7 abuts against the lower end of the limiting block 12 when the disc 7 is open. When an earthquake occurs while the disc 7 is open, the disc 7 and the valve body 1 can be integrated under the locking action of the driving force output by the driving mechanism 3 and the abutting action of the limiting block 12, thereby improving the overall rigidity and operational stability of the safety-grade fast-closing isolation valve for nuclear power plants, and preventing the disc 7 from vibrating too much and colliding with other structures or breaking the rotating shaft 6.

[0062] The aforementioned safety-grade fast-sealing isolation valve for nuclear power plants has more effective and reliable sealing performance, a compact overall structure, and strong stability, solving the problems of poor sealing performance and poor operational stability of existing isolation valves for nuclear power plants.

[0063] This nuclear power plant uses safety-grade quick-closing isolation valves to maintain building pressure below atmospheric pressure, reducing the leakage of radioactive gases. In the event of fuel assembly accidents, container operation accidents, or LOCA (loss-of-coolant) accidents, they are used to reduce the radioactivity level of exhaust air to an acceptable level. They also function as isolation and regulating valves, meaning they are also used in safety-related ventilation systems within the nuclear power plant to isolate airflow (some also require flow regulation). They can be installed at the inlet of the supply and exhaust fans. Depending on the fan operation, these safety-grade quick-closing isolation valves are remotely controlled or manually operated, and are suitable for the nuclear power plant's ventilation system.

[0064] To further explain, the valve body 1 includes a side frame 14 and a connecting frame 15. The side frames 14 are spaced apart and symmetrically arranged. The connecting frame 15 is disposed between the two side frames 14 and is connected to the upper and lower ends of the side frames 14.

[0065] The valve seat 11 is disposed between the two side frames 14 and is connected to the rear of the side frame 14. The limiting block 12 is disposed at the front of the side frame 14 and the disc 7 is located between the valve seat 11 and the limiting block 12.

[0066] By setting the side frame 14 and the connecting frame 15, the stability of the valve body 1 is ensured. In addition, the valve seat 11 is connected to the rear of the side frame 14, so that the disc 7 can abut against the sealing strip 13 when it is in the closed state, and the disc 7 can abut against the corresponding limiting block 12 when it is in the open state, so that the disc 7 is in the horizontal open state.

[0067] Specifically, such as Figure 4As shown, the connecting frame 15 is in the shape of an "arch", which improves the strength of the nuclear power plant safety-grade fast-sealing isolation valve without increasing the plate thickness and weight of the valve body 1.

[0068] Furthermore, the sealing end cap assembly 5 also includes a bearing cap 52 and a clamping plate 53. The bearing cap 52 and the clamping plate 53 are both hollow structures. One end of the bearing cap 52 is fitted with a bearing 521, and the inner wall of the other end of the bearing cap 52 is provided with an internal thread. The outer periphery of the clamping plate 53 is provided with an external thread. The external thread of the clamping plate 53 is threadedly engaged with the internal thread of the bearing cap 52. The inner wall of the bearing cap 52 is provided with a spacer ring 522, which is disposed between the internal thread and the bearing 521. The inner ring of the bearing 521 is connected to the rotating shaft 6, and the outer ring of the bearing 6 is connected to the bearing cap 52. The sealing ring 51 is pressed between the clamping plate 53 and the spacer ring 522.

[0069] The outer side wall of the side frame 14 is provided with a plurality of bases 141 at intervals, and the bearing cover 52 is connected to the corresponding base 141.

[0070] In the past, external leakage at the shaft end of isolation valves mainly relied on O-ring seals for sealing. However, after a period of use, these O-rings wear out and cannot maintain zero leakage at rated pressure. Replacement is also very troublesome, sometimes requiring disassembly of the entire isolation valve to replace the O-ring. This invention addresses this by using a bearing cover 52 and a pressure plate 53. Since the external thread of the pressure plate 53 engages with the internal thread of the bearing cover 52, when the pressure plate 53 is rotated, it engages with the spacer of the bearing cover 52 to press the O-ring 51, achieving an interference fit between the end of the rotating shaft 6 and the O-ring 51. This seals the connection between the bearing 521 and the rotating shaft 6, preventing radioactive gas from leaking out from the shaft end.

[0071] Preferably, one end of the clamping plate 53 is polygonal, and the outer periphery of the other end of the clamping plate 53 is provided with external threads. The polygonal structure facilitates the rotation operation of the clamping plate 53.

[0072] Specifically, one end of the rotating shaft 6 is connected to the bearing cover 52 via the bearing 6, and the other end of the rotating shaft 6 is also rotatably connected to the side frame 14 on the other side via the bearing.

[0073] To further explain, the limiting block 12 is cam-shaped, and the inner sidewall of the side frame 14 is provided with a plurality of limiting bolts 142. The limiting block 12 is detachably installed on the corresponding limiting bolt 142.

[0074] In some newly built nuclear power plants, isolation valves also need to have an adjustment function. When the isolation valve is in the middle position, the existing spring-assisted isolation valve cannot meet this requirement because the middle position relies entirely on the spring force to limit the position of the disc. When the wind speed is too high, the spring force is insufficient, causing the disc to vibrate. If the spring force is increased, the demand for driving force will increase, leading to an increase in investment costs. This invention, by setting the limiting block 12, enables the upper end of the disc 7 to abut against the lower end of the limiting block 12 when the disc 7 is open. When an earthquake occurs while the disc 7 is in the open state, under the locking action of the driving force output by the driving mechanism 3 and the abutting action of the limiting block 12, the disc 7 and the valve body 1 are integrated, thereby improving the overall rigidity of the safety-grade fast-closing isolation valve for nuclear power plants and preventing the disc 7 from vibrating too much and colliding with other structures or breaking the rotating shaft 6.

[0075] Specifically, when the disc plate 7 is opened, the upper end surface of the disc plate 7 abuts against the lower end of the limiting block 12, and the lower end surface of the disc plate 7 is horizontally set. The limiting block 12 can ensure that the disc plate 7 is in a horizontally opened state when it is opened. Under the action of the limiting block 12, the disc plate 7 can be prevented from vibrating too much and colliding with other structures or breaking the rotating shaft 6, thus ensuring structural stability.

[0076] Furthermore, since the limiting block 12 is cam-shaped and detachably mounted on the limiting bolt 142, rotating the limiting block 12 and finely adjusting its mounting angle can overcome the problem of error accumulation preventing the disc 7 from opening to a horizontal position. Specifically, the limiting block 12 is detachably mounted on the limiting bolt 142 via a nut, ensuring reliable installation.

[0077] Preferably, the valve body 1 further includes a positioning arm 16 and a hollow auxiliary tube 17. The side frame 14 is provided with a plurality of positioning holes 143. One end of the auxiliary tube 17 is fixedly connected to the corresponding positioning hole 143, and the other end of the auxiliary tube 17 is fixedly connected to the positioning arm 16. The rotating shaft 6 passes through the auxiliary tube 17 and the positioning hole 143 and is rotatably connected to the side frame 14.

[0078] The disc 7 is connected to the positioning arm 16 and the corresponding rotating shaft 6 via the rotating rod assembly 4. By setting the positioning arm 16 and the hollow auxiliary tube 17, and since the rotating shaft 6 passes through the auxiliary tube 17 and the positioning hole 143 and is rotatably connected to the side frame 14, the disc 7 is connected to the positioning arm 16 and the corresponding rotating shaft 6 via the rotating rod assembly 4. This eliminates the need for additional drilling to install the rotating rod assembly 4, thus avoiding welding deformation of the valve body 1.

[0079] Preferably, the profiles of the positioning hole 143 and the auxiliary tube 17 are both circles with one corner removed. By cooperating with the irregular hole and the auxiliary tube 17, the errors caused by the production process of the safety-grade fast-sealing isolation valve for nuclear power plants are solved, thereby improving the overall accuracy of the safety-grade fast-sealing isolation valve for nuclear power plants and increasing production efficiency.

[0080] To further explain, the disc plate 7 includes a blade 71, a first rotating arm 72, and a second rotating arm 73; the first rotating arm 72 is disposed between the two second rotating arms 73, and the first rotating arm 72 and the second rotating arm 73 are arranged along the length direction of the disc plate 7; the positioning arm 16 is provided with a first pin 161, and the second rotating arm 73 is provided with a second pin 731; the rotating rod assembly 4 includes an inner rotating arm 41 and an inner connecting rod 42; one end of the inner rotating arm 41 is fixedly connected to the corresponding rotating shaft 6, and the other end of the inner rotating arm 41 is connected to the first rotating arm 72 through a pin; one end of the inner connecting rod 42 is connected to the first pin 161, and the other end of the inner connecting rod 42 is connected to the second pin 731.

[0081] Because the valve structure needs to be short, the structure of the rotary rod assembly 4 needs to be more compact. If the distance between the rotating shaft 6 and the first pin 161 is too close, the strength of the valve body 1 will be significantly reduced. Therefore, by adding the positioning arm 16, the strength of the valve body 1 can be effectively avoided if the rotating shaft 6 and the first pin 161 are too close when using a compact rotary rod assembly 4. Furthermore, in some newly built nuclear power plants, the structure of the isolation valve blades is insufficient to meet the strength requirements of the equipment. Simply increasing the thickness of the blade material to improve valve strength will increase equipment weight and investment costs, and its flow resistance coefficient will also be limited. Preferably, the blade 71 is an airfoil with a smooth arched surface, such as... Figure 18 As shown, the blade 71 is in the shape of "}", which can effectively reduce the weight of the butterfly plate 7, reduce pressure loss (reduce flow resistance), and improve its strength, thereby reducing the torque requirement of the drive mechanism 3 and effectively improving the market competitiveness of the isolation valve.

[0082] To further explain, the linkage mechanism 2 includes a link 21 and a plurality of first external rotating arms 22. One end of the first external rotating arm 22 is fixedly connected to the corresponding rotating shaft 6, and the other end of the first external rotating arm 22 is connected to the link 21 via a pin. The output end of the drive mechanism 3 is connected to the link 21.

[0083] By setting the connecting rod 21, multiple rotating shafts 6 can be driven to rotate, making the opening and closing operation of the disc 7 simple and ensuring the sealing performance of the safety-grade fast-closing isolation valve for nuclear power plants.

[0084] Specifically, the connecting rod 21 is L-shaped, which can reduce the plate thickness of the connecting rod 21 and make the connecting rod 21 lighter. One end of the first external rotating arm 22 is provided with a polygonal through hole, which cooperates with the corresponding rotating shaft 6 through the polygonal through hole and is fixedly connected to the corresponding rotating shaft 6 through a positioning pin. The other end of the first external rotating arm 22 can be connected to the connecting rod 21 through a pin, copper washer, gasket and cotter pin to ensure connection stability.

[0085] Preferably, the drive mechanism 3 includes a bracket 31 and a drive device 32, and the linkage mechanism 2 further includes a second external rotating arm 23. The bracket 31 is fixedly installed on the valve body 1, the drive device 32 is installed on the bracket 31, the output shaft of the drive device 32 is fixedly connected to one end of the second external rotating arm 23, and the other end of the second external rotating arm 23 is connected to the linkage 21.

[0086] Currently, the closed isolation valves used in nuclear power plants mainly rely on spring assistance, which makes it difficult to fix the spring position, and some structures may collide with the shaft. Furthermore, the drive mechanism uses a direct-push structure that relies solely on a single rotating shaft for fixation. When subjected to severe environmental conditions such as earthquakes, the probability of malfunctions increases, making it difficult for the isolation valve to function and severely reducing the safety and reliability of the nuclear power plant. The drive device 32 of this invention drives the connecting rod 21 to swing via the second external rotating arm 23. The connecting rod 21 drives the rotating shaft 6 to rotate via the first external rotating arm 22, thereby causing the rotating shaft 6 to rotate and the corresponding disc 7 to open and close, resulting in high reliability.

[0087] Specifically, the output shaft of the drive device 32 is connected to the bracket 31 via a bearing. The drive device 32 is a rotary actuator, which can be operated electrically, manually, or pneumatically. For example, when the rotary actuator is electrically operated, it is an electric actuator. One end of the second external rotating arm 23 is fixedly connected to the output shaft of the drive device 32 via a positioning pin, and the other end of the second external rotating arm 23 is connected to the second external rotating arm 23 via a pin, a copper washer, a gasket, and a cotter pin.

[0088] Preferably, the side of the sealing strip 13 facing the disc 7 is wavy or toothed.

[0089] By setting the side of the sealing strip 13 facing the disc 7 to be wavy or toothed, the fit between the disc 7 and the sealing strip 13 can be improved, thereby improving the sealing effect.

[0090] Preferably, the sealing strip 13 has a groove 131 on the side that fits against the valve seat 11, and the valve seat 11 has an inner boss 111 that mates with the groove 131 on its inner side, and the inner boss 111 is fastened in the groove 131; or the sealing strip 13 has a retaining groove 132 at its upper and lower ends, and the valve seat 11 has a C-shaped structure, and the valve seat 11 is engaged in the retaining groove 132.

[0091] The sealing strips in existing isolation valves, designed to prevent internal leakage, have poor installation stability. When the blade is in a closed state for an extended period, the blade and sealing strip can "seep in" into each other. Once the isolation valve is opened, the sealing strip will detach, causing failure and seriously jeopardizing the safety of the nuclear power plant. By setting a structure in which the groove 131 engages with the inner boss 111, or by setting a structure in which the slot 132 engages with the valve seat 11, the bonding between the valve seat 11 and the sealing strip 13 can be improved. This ensures that the sealing strip 13 is tightly fastened to the valve seat 11. Even if the disc 7 and the sealing strip 13 "seep in" into each other, the disc 7 will not pull the sealing strip 13 off the valve seat 11 when it is opened. This ensures that the safety-grade fast-closing isolation valve for nuclear power plants will not experience internal leakage, meeting the safety requirements for use.

[0092] Furthermore, the inner boss 111 can be obtained by cold stamping or by hot forming. In another embodiment of the invention, the upper and lower ends of the sealing strip 13 are respectively provided with slots 132, and the C-shaped valve seat 11 is formed by two "B"-shaped valve seat bodies connected by bolts, nuts or riveting. Preferably, the front end face of the valve seat 11 is also provided with a reinforcing plate 112, which is disposed between the upper and lower sealing strips 13. The valve seat 11 and the reinforcing plate 112 are combined to form a "mountain"-shaped valve body 1, which can improve the overall rigidity of the valve body 1 and increase the strength of the isolation valve.

[0093] The technical principles of the present invention have been described above with reference to specific embodiments. These descriptions are merely for explaining the principles of the invention and should not be construed as limiting the scope of protection of the invention in any way. Based on this explanation, those skilled in the art can readily conceive of other specific embodiments of the invention without inventive effort, and these embodiments will all fall within the scope of protection of the present invention.

Claims

1. A safety class quick-exhaust isolation valve for nuclear power plants, characterized in that, It includes a valve body, linkage mechanism, drive mechanism, multiple rotary rod assemblies, multiple sealing end cap assemblies, multiple rotating shafts, and multiple discs; The sealing end cap assembly is disposed on the valve body. The rotating shaft is rotatably connected to the valve body and the corresponding sealing end cap assembly. The sealing end cap assembly includes a sealing ring, a bearing cover, and a pressure plate. The bearing cover and the pressure plate are hollow structures. A bearing is embedded at one end of the bearing cover, and an internal thread is provided on the inner wall of the other end of the bearing cover. An external thread is provided on the outer circumference of the pressure plate. The external thread of the pressure plate is threadedly engaged with the internal thread of the bearing cover. A spacer is provided on the inner wall of the bearing cover. The spacer is disposed between the internal thread and the bearing. The inner ring of the bearing is connected to the rotating shaft, and the outer ring of the bearing is connected to the bearing cover. The sealing ring is pressed between the pressure plate and the spacer. The sealing ring is used to seal the connection between the rotating shaft and the sealing end cap assembly. The valve body includes a side frame, and a plurality of bases are spaced apart on the outer side wall of the side frame. The bearing cover is connected to the corresponding base. Multiple rotating shafts are arranged vertically at intervals on the valve body. The disc is connected to the valve body and the corresponding rotating shaft through the rotating rod assembly. The multiple rotating shafts are respectively connected to the linkage mechanism. The output end of the drive mechanism is connected to the linkage mechanism. The drive mechanism drives the rotating shaft to rotate through the linkage mechanism. The rotation of the rotating shaft drives the corresponding disc to rotate, thereby realizing the opening and closing of the disc. The valve body is provided with a valve seat and multiple limiting blocks. A sealing strip is fastened inside the valve seat. When the disc is closed, both ends of the disc abut against the sealing strip. The limiting blocks are arranged one-to-one with the discs and are located in front of the corresponding discs. When the disc is open, the upper surface of the disc abuts against the lower end of the limiting block, and the disc is in a horizontally open state. The limiting block is cam-shaped, and the inner sidewall of the side frame is provided with multiple limiting bolts. The limiting block is detachably installed on the corresponding limiting bolt. The sealing strip has a groove on the side that fits against the valve seat, and the valve seat has an inner boss that mates with the groove on the inner side, and the inner boss is fastened into the groove. Alternatively, the sealing strip may have grooves at its upper and lower ends, and the valve seat may have a C-shaped structure and be fitted into the grooves.

2. The safety class quick-exclosure isolation valve for nuclear power plants according to claim 1, characterized by The valve body includes a side frame and a connecting frame. The side frames are spaced apart and symmetrically arranged. The connecting frame is disposed between the two side frames and is connected to the upper and lower ends of the side frames. The valve seat is disposed between the two side frames and is connected to the rear of the side frames. The limiting block is disposed at the front of the side frames, and the disc is located between the valve seat and the limiting block.

3. The safety class quick-exclosure isolation valve for nuclear power plants according to claim 1, characterized by The valve body also includes a positioning arm and a hollow auxiliary tube. The side frame is provided with multiple positioning holes. One end of the auxiliary tube is fixedly connected to the corresponding positioning hole, and the other end of the auxiliary tube is fixedly connected to the positioning arm. The rotating shaft passes through the auxiliary tube and the positioning hole and is rotatably connected to the side frame. The disc is connected to the positioning arm and the corresponding rotating shaft via the rotary rod assembly.

4. The safety class quick-exclosure isolation valve for nuclear power plants according to claim 3, characterized by The disc includes blades, a first spiral arm, and a second spiral arm; The first rotating arm is disposed between the two second rotating arms, and the first rotating arm and the second rotating arm are arranged along the length direction of the disc. The positioning arm is provided with a first pin, and the second rotating arm is provided with a second pin. The rotating rod assembly includes an inner rotating arm and an inner connecting rod. One end of the inner rotating arm is fixedly connected to the corresponding rotating shaft, and the other end of the inner rotating arm is connected to the first rotating arm via a pin. One end of the inner connecting rod is connected to the first pin, and the other end of the inner connecting rod is connected to the second pin.

5. The safety class quick-exclosure isolation valve for nuclear power plants according to claim 1, characterized by The linkage mechanism includes a connecting rod and a plurality of first external rotating arms. One end of the first external rotating arm is fixedly connected to the corresponding rotating shaft, and the other end of the first external rotating arm is connected to the connecting rod through a pin. The output end of the drive mechanism is connected to the connecting rod.

6. The safety class quick-exclosure isolation valve for nuclear power plants according to claim 5, characterized in that, The drive mechanism includes a bracket and a drive device. The linkage mechanism also includes a second external rotating arm. The bracket is fixedly installed on the valve body. The drive device is installed on the bracket. The output shaft of the drive device is fixedly connected to one end of the second external rotating arm. The other end of the second external rotating arm is connected to the linkage.

7. The safety class quick-exclosure isolation valve for nuclear power plants according to claim 1, characterized by The side of the sealing strip facing the disc is wavy or toothed.

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