Pilot-operated type emergency pressure release valve special for nuclear power unit

Abstract

The pilot-operated type emergency pressure release valve special for the nuclear power unit comprises a main valve body and a pilot valve, a pressure guiding pipeline is arranged between the main valve body and the pilot valve, the main valve body and the pilot valve communicate with each other through the pressure guiding pipeline, an exhaust port is formed in the pilot valve, and a pressure closing assembly is arranged in the pilot valve; the pressure closing assembly opens or closes the exhaust port through sliding and comprises a mounting plate, an elastic part, a pressure piston block, a pressure sensor and a trigger switch, the mounting plate is mounted in the pilot valve, the elastic part is arranged in the pilot valve, one end of the elastic part abuts against the mounting plate, and the pressure piston block is fixed to the end, away from the mounting plate, of the elastic part; the pressure piston block is slidably arranged in the pilot valve, the pressure sensor is mounted on the mounting plate, elastic force of the elastic part acts on the pressure sensor, the trigger switch is mounted in the pilot valve, and the pressure piston block presses the trigger switch when sliding to open the exhaust port. The method has the effect that the take-off pressure condition of the pilot-operated type pressure release valve can be known conveniently in real time.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of pipeline valve body, especially to a pilot emergency relief valve special for nuclear power unit. BACKGROUND

[0002] The pilot emergency relief valve is also called pilot safety relief valve, which is a non-direct acting safety protection valve controlled by pilot valve, belonging to automatic valve, mainly used for overpressure protection of boiler, pressure vessel and pipeline system. When the medium pressure exceeds the set value, the pilot valve drives the main valve to open to discharge the medium, and the pressure falls automatically after closing, including micro-opening and full-opening types, which can be divided into closed type and non-closed type according to structure.

[0003] The pilot emergency relief valve is an important safety device in nuclear power equipment, mainly used for overpressure protection of reactor loop system, which drives the main valve to discharge the medium through the rapid response of the pilot valve, to ensure that the system pressure is always within the safety threshold.

[0004] The pilot emergency relief valve needs to be checked regularly after being used for a period of time to avoid the take-off pressure being too large or too small to discharge at the correct pressure, but when the take-off pressure changes due to damage of the pilot emergency relief valve during the period of regular inspection, it is easy to cause safety hazards of overpressure protection during the whole period. SUMMARY

[0005] In order to facilitate real-time understanding of the take-off pressure of the pilot relief valve, the present application provides a pilot emergency relief valve special for nuclear power unit.

[0006] The pilot emergency relief valve special for nuclear power unit provided by the present application adopts the following technical scheme: A pilot emergency relief valve special for nuclear power unit, comprising a main valve body and a pilot valve, a pressure lead pipe is arranged between the main valve body and the pilot valve, the main valve body and the pilot valve are connected and communicated through the pressure lead pipe, an exhaust port is formed on the pilot valve, a pressure closing assembly is arranged in the pilot valve, the pressure closing assembly opens or closes the exhaust port through sliding, the pressure closing assembly comprises a mounting plate, an elastic member, a pressure piston block, a pressure sensor and a trigger switch, the mounting plate is installed in the pilot valve, the elastic member is arranged in the pilot valve, one end of the elastic member abuts against the mounting plate, the pressure piston block is fixed to one end of the elastic member away from the mounting plate, the pressure piston block is slidingly arranged in the pilot valve, and the exhaust port is opened or closed through sliding, the pressure sensor is installed on the mounting plate, the elastic force of the elastic member acts on the pressure sensor, and the trigger switch is installed in the pilot valve and is pressed when the pressure piston block slides to open the exhaust port.

[0007] By adopting the technical scheme, the pressure sensor and the trigger switch detect the take-off pressure of the driving pressure piston block when the exhaust port is opened. When the trigger switch is pressed and triggered, and the take-off pressure detected by the pressure sensor is lower or higher than the preset value, it indicates that the structure in the pilot valve is damaged and needs to be replaced or repaired in time. The pressure sensor and the trigger switch can be used to conveniently and timely understand the take-off pressure of the pilot relief valve, thereby reducing the probability of equipment damage and safety accidents.

[0008] Optionally, the mounting plate comprises an upper plate body and a lower plate body, both of which are mounted in the pilot valve. The pressure sensor is mounted on the side of the upper plate body facing the lower plate body. The lower plate body is slidably arranged on the upper plate body and abuts against the pressure sensor. The elastic member abuts against the side of the lower plate body away from the pressure sensor.

[0009] By adopting the technical scheme, the pressure sensor and the trigger switch detect the take-off pressure of the driving pressure piston block when the exhaust port is opened. When the trigger switch is pressed and triggered, and the take-off pressure detected by the pressure sensor is lower or higher than the preset value, it indicates that the structure in the pilot valve is damaged and needs to be replaced or repaired in time. The pressure sensor and the trigger switch can be used to conveniently and timely understand the take-off pressure of the pilot relief valve, thereby reducing the probability of equipment damage and safety accidents.

[0010] Optionally, the pilot valve is provided with an opening and closing opening at the top, and a detachable opening and closing plate is installed at the opening and closing opening. The opening and closing opening is opened by detaching the opening and closing plate.

[0011] By adopting the technical scheme, the opening and closing opening can be opened to facilitate the maintenance or replacement of the pressure closing assembly when the take-off pressure is higher or lower than the preset value.

[0012] Optionally, a limiting ring is fixedly arranged in the pilot valve, and the pressure piston block abuts against the limiting ring when closing the exhaust port.

[0013] By adopting the technical scheme, the limiting ring can limit the sliding of the pressure piston block, reduce the influence of the pressure piston block on the pressure pipeline connected between the pilot valve and the main valve body, and reduce the influence of the pressure piston block on the pressure pipeline.

[0014] Optionally, an adjusting bolt is threadedly connected to the opening and closing plate and abuts against the side of the upper plate body away from the lower plate body.

[0015] By adopting the technical scheme, the adjusting bolt can be rotated to adjust the compression or expansion of the elastic member, thereby adjusting the force required to drive the pressure piston block to slide and adjusting the take-off pressure. The pilot valve can be used for different pressure requirements, and the pilot valve can continue to be used when the take-off pressure is different from the preset pressure.

[0016] Optionally, the pressure pipeline comprises a flow guide pipe and a return pipe. One end of the flow guide pipe is fixedly arranged at the liquid inlet end of the main valve body, and the other end is detachably installed at the pilot valve. One end of the return pipe is installed at the liquid outlet end of the main valve body, and the other end is detachably installed at the pilot valve.

[0017] By adopting the technical scheme, the pilot valve can be detached from the main valve body through detachable connection of the drainage pipe and the return pipe with the pilot valve, so that the pilot valve can be conveniently replaced when the pilot valve is damaged.

[0018] Optionally, a connecting assembly is arranged between the drainage pipe and the pilot valve, the connecting assembly comprising a connecting pipe and a connecting sleeve, the connecting pipe being fixedly arranged on the pilot valve, and the connecting sleeve being slidably arranged at one end of the drainage pipe connected with the pilot valve, and the connecting sleeve being threadedly connected with the connecting pipe through rotation.

[0019] By adopting the technical scheme, the connecting assembly can conveniently detach the pilot valve from the drainage pipe.

[0020] Optionally, one end of the drainage pipe connected with the pilot valve is provided with a flow interruption mechanism, the flow interruption mechanism comprising a flow interruption plate, flow interruption wedges and flow interruption rods, the flow interruption plate being provided with a plurality of blocks, the flow interruption plate being slidably arranged in the drainage pipe, the flow interruption wedges being provided with a plurality of blocks and being fixedly arranged on the flow interruption plate, and the flow interruption rods being provided with a plurality of blocks, the flow interruption rods being slidably arranged on the drainage pipe, one end of the flow interruption rods abutting against the flow interruption wedges, and the other end of the flow interruption rods extending out of the drainage pipe, the flow interruption rods being slidably driven toward the flow interruption wedges to close the internal passage of the drainage pipe.

[0021] By adopting the technical scheme, the flow interruption mechanism can interrupt the drainage pipe after the pilot valve is detached, thereby reducing the probability of medium leakage from outside of the drainage pipe.

[0022] Optionally, the flow interruption rods extend out of the drainage pipe from a side of the connecting sleeve away from the pilot valve, and the flow interruption rods are driven to slide toward the flow interruption wedges under the action of gravity after the connecting sleeve is detached from the connecting pipe.

[0023] By adopting the technical scheme, the flow interruption rods are arranged toward the connecting sleeve, and the flow interruption mechanism can be driven to interrupt the drainage pipe through gravity of the flow interruption rods when the connecting sleeve is detached from the connecting pipe, thereby ensuring that the drainage valve can be interrupted when the pilot valve is detached, and reducing the probability of medium leakage due to forgetting to interrupt the drainage valve by an operator.

[0024] Optionally, a maintenance opening is arranged at the top of the main valve body, and a sealing plate is detachably arranged on the maintenance opening.

[0025] By adopting the technical scheme, the maintenance opening can facilitate maintenance of the inside of the main valve body.

[0026] In summary, the present application has at least one of the following beneficial technical effects: 1. The pressure sensor and the trigger switch detect the take-off pressure of the exhaust port when the pressure piston block is driven, and when the trigger switch is pressed and triggered, the take-off pressure detected by the pressure sensor is lower or higher than the preset value, indicating that the structure in the pilot valve needs to be replaced or repaired in time. Through the setting of the pressure sensor and the trigger switch, the take-off pressure of the pilot relief valve can be easily and timely understood, and the probability of equipment damage and safety accidents is reduced; 2. The opening and closing opening can facilitate the opening of the pilot valve to repair or replace the pressure closing assembly when the take-off pressure is higher or lower than the preset value, and the limit ring can limit the sliding of the pressure piston block, thereby reducing the influence of the pressure piston block on the pressure pipeline connected with the pilot valve and the main valve body, thereby reducing the influence of the pressure piston block on the pressure pipeline connected with the pilot valve and the main valve body; 3. The take-off pressure can be adjusted by rotating the adjusting bolt to compress or stretch the elastic member, thereby adjusting the force required to drive the pressure piston block to slide, realizing the adjustment of the take-off pressure, so that the pilot valve can be used for different pressure requirements, and when the take-off pressure is different from the preset pressure, the pilot valve can be used by adjusting; 4. The detachable connection of the drain pipe and the return pipe with the pilot valve can detach the pilot valve from the main valve body, so that the pilot valve can be easily replaced when the pilot valve is damaged; 5. The cutoff mechanism can cut off the drain pipe after the pilot valve is detached, thereby reducing the probability of medium leakage from the drain pipe; the cutoff rod is arranged towards the connecting nut, and can drive the cutoff mechanism to cut off the drain pipe by its own gravity when the connecting nut is disconnected from the connecting pipe, thereby ensuring that the drain valve can be cut off when the pilot valve is detached, and reducing the probability of medium leakage caused by the operator forgetting to cut off the drain valve; 6. The maintenance opening can facilitate the maintenance of the inside of the main valve body. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 is a schematic view of the overall structure of the embodiment of the present application.

[0028] Figure 2 is a sectional view of the overall structure of the embodiment of the present application.

[0029] Figure 3 is Figure 2 is an enlarged view of part A in

[0030] Figure 4 is Figure 2 is an enlarged view of part B in

[0031] Explanation of reference numerals: 1, main valve body; 2, pilot valve; 3, pressure lead pipe; 31, flow lead pipe; 32, return pipe; 4, inlet; 5, outlet; 6, valve plug; 7, exhaust port; 8, pressure closing assembly; 81, mounting plate; 811, upper plate body; 812, lower plate body; 82, elastic member; 83, pressure piston block; 84, pressure sensor; 85, trigger switch; 9, opening and closing opening; 10, opening and closing plate; 11, limiting ring; 12, adjusting bolt; 13, connecting assembly; 131, connecting pipe; 132, connecting screw sleeve; 14, cut-off mechanism; 141, cut-off plate; 142, cut-off wedge block; 143, cut-off rod; 15, access hole; 16, sealing plate; 17, plugging plate. DETAILED DESCRIPTION

[0032] The following will be described in detail in combination with the accompanying drawings. Figures 1-4 Further detailed description will be made to the present application.

[0033] First of all, it needs to be explained here that in the description of the present application, if the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and other orientation words appear, the orientation or position relationship indicated thereby is based on the orientation or position relationship shown in the drawings, and is only for the convenience of description, and does not indicate or imply that the device or element indicated thereby must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application; in addition, if the terms "first", "second", "third" and the like appear, they are only for the purpose of description, and cannot be understood as indicating or implying relative importance. In addition, in the present application, unless otherwise explicitly specified and limited, if the terms "mounting", "connecting", "connecting" appear, they should be understood in a broad sense, for example, can be fixedly connected, can also be detachably connected, can be limitingly connected such as interference fit, transition fit, or integrally connected; can be directly connected, or indirectly connected through an intermediate medium; therefore, for those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0034] The present application discloses a kind of nuclear power unit special pilot emergency pressure relief valve, refer to Figure 1 And Figure 2, including the main valve body 1 and the pilot valve 2, the main valve body 1 and the pilot valve 2 are provided with the pressure lead pipe 3, the main valve body 1 and the pilot valve 2 are connected and communicated with each other through the pressure lead pipe 3, the main valve body 1 is provided with the bottom inlet 4 at one end, the main valve body 1 is provided with the outlet 5 at the side, the valve plug 6 is slidably arranged in the main valve body 1, the valve plug 6 is disconnected or communicated with the inlet 4 and the outlet 5 through sliding, the pilot valve 2 is provided with the exhaust port 7, the pressure closing assembly 8 is arranged in the pilot valve 2, the pressure closing assembly 8 opens or closes the exhaust port 7 through sliding, the pressure closing assembly 8 includes the mounting plate 81, the elastic element 82, the pressure piston block 83, the pressure sensor 84 and the trigger switch 85, the mounting plate 81 is installed in the pilot valve 2, the elastic element 82 is arranged in the pilot valve 2, the elastic element 82 is selected as the spring in the embodiment, one end of the elastic element 82 abuts against the mounting plate 81, the pressure piston block 83 is fixed at one end of the elastic element 82 away from the mounting plate 81, the pressure piston block 83 is slidably arranged in the pilot valve 2, the pressure lead pipe 3 is connected and communicated with each other through the pressure lead pipe 3, the pressure piston block 83 opens or closes the exhaust port 7 through sliding, the pressure sensor is installed on the mounting plate 81, the elastic force of the elastic element 82 acts on the pressure sensor 84, the trigger switch 85 is installed in the pilot valve 2, the pressure piston block 83 presses the trigger switch 85 when the pressure piston block 83 opens the exhaust port 7 through sliding, one end of the inlet 4 of the main valve body 1 is connected to the pipeline of the nuclear power equipment, then the outlet 5 of the main valve body 1 is connected to the storage equipment receiving the pressure relief medium or the processing equipment processing the medium, when the medium in the pipeline of the nuclear power equipment normally flows, the medium enters the pilot valve 2 through the pressure lead pipe 3 and then returns to the main valve body 1, the medium acts on the valve plug 6 in the main valve body 1 to limit the valve plug 6 to slide and communicate the inlet 4 and the outlet 5 of the main valve body 1, when the pressure of the medium in the nuclear power equipment is higher than the take-off pressure in the pilot valve 2, the medium drives the pressure piston block 83 to slide and open the exhaust port 7 to make the medium discharge from the exhaust port 7, at this time, the pressure of the medium on the valve plug 6 is removed, the medium in the nuclear power equipment drives the valve plug 6 to slide and communicate the inlet 4 and the outlet 5 of the main valve body 1 to discharge the medium, when the pressure drops to a safe value, the pressure piston block 83 rebounds and closes the exhaust port 7 under the action of the elastic element 82, the medium flows into the main valve body 1 through the pressure lead pipe 3 to limit the sliding of the valve plug 6, when the pressure piston block 83 opens the exhaust port 7, the pressure piston block 83 presses the trigger switch 85, at the same time, the pressure sensor 84 detects the take-off pressure for driving the pressure piston block 83, when the trigger switch 85 is pressed to trigger, if the take-off pressure detected by the pressure sensor 84 is lower than or higher than the preset value, it indicates that the structure in the pilot valve 2 is damaged and needs to be replaced or repaired in time, through the setting of the pressure sensor 84 and the trigger switch 85, the take-off pressure of the pilot pressure relief valve can be conveniently and timely understood, and the probability of safety accidents caused by equipment damage is reduced.

[0035] Refer to Figure 2 and Figure 3, the mounting plate 81 includes an upper plate body 811 and a lower plate body 812, both of which are mounted in the pilot valve 2, the pressure sensor 84 is mounted on the upper plate body 811 towards the lower plate body 812 side, the lower plate body 812 is slidingly arranged on the upper plate body 811, the lower plate body 812 abuts the pressure sensor 84, the elastic member 82 abuts the lower plate body 812 away from the pressure sensor 84 side, when the elastic member 82 acts on the pressure sensor 84, the uneven distribution of the driving force of the elastic member 82 can easily lead to inaccurate detection value of the pressure sensor 84; by arranging the pressure sensor 84 on the lower plate body 812, the driving force of the elastic member 82 can be fully applied to the lower plate body 812, and the lower plate body 812 can be uniformly applied to the pressure sensor 84, thereby improving the detection accuracy of the pressure sensor 84.

[0036] With reference to Figure 2 and Figure 3 , the top of the pilot valve 2 is provided with an opening and closing opening 9, and the opening and closing opening 9 is detachably provided with an opening and closing plate 10. The opening and closing opening 9 is opened by detaching the opening and closing plate 10. The opening and closing opening 9 can be opened to facilitate the maintenance or replacement of the pressure closing assembly 8 of the pilot valve 2 when the take-off pressure is higher or lower than the preset value. The pilot valve 2 is fixedly provided with a limiting ring 11, and the pressure piston block 83 abuts the limiting ring 11 when closing the exhaust port 7. The limiting ring 11 can limit the sliding of the pressure piston block 83, reduce the sliding of the pressure piston block 83 to close the pilot valve 2 and the pilot valve 2, and reduce the influence of the pressure piston block 83 on the pilot valve 2. The opening and closing plate 10 is threadedly connected with an adjusting bolt 12, and the adjusting bolt 12 abuts the upper plate body 811 away from the lower plate body 812 side. By rotating the adjusting bolt 12, the elastic member 82 can be compressed or stretched, thereby adjusting the force required to drive the pressure piston block 83 to slide, realizing the adjustment of the take-off pressure, and making the pilot valve 2 applicable to different pressure requirements. When the take-off pressure is different from the preset pressure, the pilot valve 2 can continue to be used by adjusting.

[0037] With reference to Figure 2 and Figure 4The pressure-sensing pipe 3 includes a drain pipe 31 and a return pipe 32. One end of the drain pipe 31 is fixed to the liquid inlet end of the main valve body 1, and the other end is detachably installed on the pilot valve 2. One end of the return pipe 32 is installed at the liquid outlet end of the main valve body 1, and the other end is detachably installed on the pilot valve 2. The detachable connection between the drain pipe 31 and the return pipe 32 and the pilot valve 2 allows the pilot valve 2 to be removed from the main valve body 1, thus facilitating the replacement of the pilot valve 2 when it is damaged. The drain pipe 31 is connected to the pilot valve 2 and the return pipe 32. A connecting assembly 13 is provided at the connection point between the pilot valve 2 and the pilot valve 2. The connecting assembly 13 includes a connecting pipe 131 and a connecting threaded sleeve 132. The connecting pipe 131 is fixed on the pilot valve 2, and the connecting threaded sleeve 132 is slidably sleeved on one end of the drain pipe 31 that connects to the pilot valve 2. The connecting threaded sleeve 132 is connected to the connecting pipe 131 by rotational thread. The connecting assembly 13 can facilitate the disassembly and assembly between the pilot valve 2 and the drain pipe 31, as well as between the pilot valve 2 and the return pipe 32, thereby facilitating the replacement of the pilot valve 2 when it is damaged.

[0038] Reference Figure 2 and Figure 4 A flow-stopping mechanism 14 is provided at one end of the drainage pipe 31 connected to the pilot valve 2. The flow-stopping mechanism 14 includes a flow-stopping plate 141, a flow-stopping wedge 142, and a flow-stopping rod 143. Several flow-stopping plates 141 are provided. In this embodiment, six flow-stopping plates 141 are provided. The flow-stopping plates 141 are slidably disposed inside the drainage pipe 31. The flow-stopping plates 141 open or cut off the internal flow channel of the drainage pipe 31 by sliding. Several flow-stopping wedges 142 are provided. In this embodiment, six flow-stopping wedges 142 are provided. The six flow-stopping wedges 142 are fixed on the six flow-stopping plates 141 respectively. Several flow-stopping rods 143 are provided. In this embodiment, six flow-stopping rods 143 are provided. All six flow-stopping rods 143 are slidably disposed on the drainage pipe 31. The flow-stopping rods 143 are disposed corresponding to the flow-stopping wedges 142, and one end of the flow-stopping rod 143 abuts against the flow-stopping wedge 142. 2. The other end extends out of the drain pipe 31. The throttling rod 143 slides toward the throttling wedge 142 to drive the throttling plate 141 to close the internal channel of the drain pipe 31. The throttling mechanism 14 can cut off the drain pipe 31 after the pilot valve 2 is disassembled, reducing the probability of the medium leaking out of the drain pipe 31. The throttling rod 143 extends out of the drain pipe 31 on the side of the connecting sleeve 132 away from the pilot valve 2. After the connecting sleeve 132 is separated from the connecting pipe 131, it drives the throttling rod 143 to slide toward the throttling wedge 142 under the action of gravity. The throttling rod 143 is set toward the connecting sleeve 132. When the connecting sleeve 132 is separated from the connecting pipe 131, it can drive the throttling mechanism 14 to cut off the drain pipe 31 by its own gravity, thereby ensuring that the drain valve can be cut off when the pilot valve 2 is disassembled, reducing the probability of the medium leaking out due to the operator forgetting to cut off the drain valve.

[0039] Reference Figure 1 and Figure 2The top of the main valve body 1 is provided with an inspection opening 15, and a sealing plate 16 is detachably installed on the inspection opening 15. The inspection opening 15 can facilitate the inspection of the inside of the main valve body 1. The inlet 4 of the main valve body 1 is provided with a blocking plate 17. The blocking plate 17 blocks the inside passage of the inlet 4 by sliding. When the inside of the main valve body 1 is damaged, the inlet 4 can be blocked by the blocking plate 17. Then, the inside of the main valve body 1 can be inspected by detaching the sealing plate 16. After the inspection is completed, the sealing plate 16 is reinstalled on the main valve body 1. Then, the inlet 4 is opened by sliding the blocking plate 17, and the main valve body 1 is used normally again. When the inlet 4 is opened by sliding the blocking plate 17, the blocking plate 17 extends out of the main valve body 1 and covers the inlet 4 of the main valve body 1, thereby reducing the probability of the bolts connected to the inlet 4 from being detached.

[0040] The implementation principle of the embodiment of the present application is as follows: the pilot valve 2 is installed on the main valve body 1, the pilot valve 2 is connected and communicated with the main valve body 1 through the pressure lead pipe 3, then the take-off pressure of the pressure piston block 83 is adjusted by adjusting the screw 12, the pressure sensor 84 and the trigger switch 85 are connected with the computer, the situation of the pressure sensor 84 and the trigger switch 85 is monitored by the computer, then the main valve body 1 is installed on the loop system of the reactor, the inlet 4 of the main valve body 1 is opened by sliding the blocking plate 17, and the installation of the pilot emergency relief valve is completed. When the pressure of the loop system of the reactor exceeds the take-off pressure of the pilot valve 2, the pressure drives the pressure piston block 83 to slide and open the exhaust port 7. The pressure acting on the valve plug 6 of the pressure lead pipe 3 is removed, the valve plug 6 is opened for pressure relief. At the same time, the pressure piston block 83 presses the trigger switch 85. When the computer detects that the trigger switch 85 is triggered, the computer detects whether the pressure detected by the pressure sensor 84 is the same as the preset take-off pressure. When the detected take-off pressure is different from the preset pressure, the computer feeds back to the staff to adjust or inspect the equipment.

[0041] It should be noted that the above embodiments are only used to illustrate the present application and not to limit the technical solutions described in the present application. Although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that the skilled in the art can still modify or equivalently replace the present application, and all technical solutions and improvements that do not deviate from the spirit and scope of the present application should be covered in the scope of the claims of the present application.

Claims

1. A pilot-operated emergency pressure relief valve for nuclear power units, comprising a main valve body (1) and a pilot valve (2), wherein a pressure-feeding pipe (3) is provided between the main valve body (1) and the pilot valve (2), the main valve body (1) and the pilot valve (2) are interconnected and communicate with each other through the pressure-feeding pipe (3), an exhaust port (7) is provided on the pilot valve (2), and a pressure closing assembly (8) is provided inside the pilot valve (2), wherein the pressure closing assembly (8) opens or closes the exhaust port (7) by sliding, characterized in that: The pressure closing assembly (8) includes a mounting plate (81), an elastic element (82), a pressure piston block (83), a pressure sensor (84), and a trigger switch (85). The mounting plate (81) is installed inside the pilot valve (2). The elastic element (82) is located inside the pilot valve (2), with one end of the elastic element (82) abutting against the mounting plate (81). The pressure piston block (83) is fixed to one end of the elastic element (82) away from the mounting plate (81). The pressure piston block (83) is slidably located inside the pilot valve (2) and opens or closes the exhaust port (7) by sliding. The pressure sensor is installed on the mounting plate (81), and the elastic force of the elastic element (82) acts on the pressure sensor (84). The trigger switch (85) is installed inside the pilot valve (2). When the pressure piston block (83) slides to open the exhaust port (7), the trigger switch (85) is pressed.

2. The pilot-operated emergency pressure relief valve for nuclear power units according to claim 1, characterized in that: The mounting plate (81) includes an upper plate (811) and a lower plate (812). Both the upper plate (811) and the lower plate (812) are installed inside the pilot valve (2). The pressure sensor (84) is installed on the side of the upper plate (811) facing the lower plate (812). The lower plate (812) is slidably disposed on the upper plate (811) and abuts against the pressure sensor (84). The elastic element (82) abuts against the side of the lower plate (812) away from the pressure sensor (84).

3. A pilot-operated emergency pressure relief valve for nuclear power units according to claim 2, characterized in that: The pilot valve (2) has an opening and closing opening (9) at the top. An opening and closing plate (10) is detachably installed at the opening and closing opening (9). The opening and closing opening (9) is opened by removing the opening and closing plate (10).

4. A pilot-operated emergency pressure relief valve for nuclear power units according to claim 3, characterized in that: The pilot valve (2) is fixed with a limiting ring (11), and the pressure piston block (83) abuts against the limiting ring (11) when closing the exhaust port (7).

5. A pilot-operated emergency pressure relief valve for nuclear power units according to claim 4, characterized in that: The opening and closing plate (10) is threaded with an adjusting bolt (12), which abuts against the side of the upper plate (811) away from the lower plate (812).

6. A pilot-operated emergency pressure relief valve for nuclear power units according to claim 1, characterized in that: The pressure-sensing pipe (3) includes a flow pipe (31) and a return pipe (32). One end of the flow pipe (31) is fixed to the liquid inlet end of the main valve body (1), and the other end is detachably installed on the pilot valve (2). One end of the return pipe (32) is installed at the liquid outlet end of the main valve body (1), and the other end is detachably installed on the pilot valve (2).

7. A pilot-operated emergency pressure relief valve for nuclear power units according to claim 6, characterized in that: A connecting assembly (13) is provided between the drainage tube (31) and the pilot valve (2). The connecting assembly (13) includes a connecting tube (131) and a connecting threaded sleeve (132). The connecting tube (131) is fixed on the pilot valve (2). The connecting threaded sleeve (132) is slidably sleeved on one end of the drainage tube (31) connected to the pilot valve (2). The connecting threaded sleeve (132) is connected to the connecting tube (131) by a rotating thread.

8. A pilot-operated emergency pressure relief valve for nuclear power units according to claim 7, characterized in that: The diversion pipe (31) is connected to the pilot valve (2) and a flow-stopping mechanism (14) is provided at one end. The flow-stopping mechanism (14) includes a flow-stopping plate (141), a flow-stopping wedge (142), and a flow-stopping rod (143). Several flow-stopping plates (141) are provided and are slidably disposed inside the diversion pipe (31). Several flow-stopping wedges (142) are provided and are fixed on the flow-stopping plate (141) respectively. Several flow-stopping rods (143) are provided and are slidably disposed on the diversion pipe (31). One end of the flow-stopping rod (143) abuts against the flow-stopping wedge (142) and the other end extends out of the diversion pipe (31). The flow-stopping rod (143) slides toward the flow-stopping wedge (142) to drive the flow-stopping plate (141) to close the internal channel of the diversion pipe (31).

9. A pilot-operated emergency pressure relief valve for nuclear power units according to claim 8, characterized in that: The flow-stopping rod (143) extends out of the drain pipe (31) on the side of the connecting sleeve (132) away from the pilot valve (2). After the connecting sleeve (132) is separated from the connecting pipe (131), the flow-stopping rod (143) is driven to slide toward the flow-stopping wedge (142) under the action of gravity.

10. A pilot-operated emergency pressure relief valve for nuclear power units according to claim 1, characterized in that: The main valve body (1) has an inspection port (15) on its top, and a sealing plate (16) is detachably installed on the inspection port (15).

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