Hydraulic control mechanism and driving system of high-pressure valve of nuclear steam turbine

Abstract

Nuclear power turbine high pressure valve hydraulic control mechanism and driving system. In the first hydraulic passage of the nuclear power turbine high pressure valve hydraulic control mechanism, the first end of the first emergency electromagnetic valve is connected with the oil supply device through an oil return passage, the second end is connected with the control oil chamber of the first pilot cartridge valve through a first throttle hole, and is also connected with the first end of the first check valve; the second end of the first check valve is connected with the pressure oil chamber of the first pilot cartridge valve, and is also connected with the first end of the first main cartridge valve; the second end of the first main cartridge valve is connected with the driving mechanism through a power passage; the first pilot cartridge valve and the first main cartridge valve are also connected with the oil supply device through oil return passages; in the case that the first emergency electromagnetic valve is closed by power-off, the first pilot cartridge valve and the first main cartridge valve are opened in turn, forming an oil path from the driving mechanism to the oil supply device. The nuclear power turbine high pressure valve hydraulic control mechanism can eliminate the driving mechanism failure.

Description

Technical Field

[0001] This application relates to the field of hydraulic control technology, and in particular to a hydraulic control mechanism and drive system for high-pressure steam valves of nuclear power turbines. Background Technology

[0002] Currently, the operation of megawatt-class nuclear power turbines has been plagued by drive mechanism failures, which prevent the turbines from starting up during the upward phase, causing power generation delays. The failure rate is relatively high.

[0003] In traditional technologies, to solve the failure of the drive mechanism of a megawatt nuclear power turbine to operate, the control oil chamber area of ​​the pilot cartridge valve in the hydraulic control mechanism of the high-pressure steam valve of the nuclear power turbine is made larger than the pressure chamber. Specifically, this may include increasing the spring force of the pilot cartridge valve and shortening the cleaning cycle of the cartridge valve.

[0004] However, in the process of troubleshooting failure to operate, the hydraulic control mechanism for high-pressure steam valves in nuclear power turbines has problems such as affecting the fast-closing function of the drive mechanism and being unable to completely eliminate the failure to operate. Summary of the Invention

[0005] Based on this, it is necessary to provide a hydraulic control mechanism and drive system for the high-pressure steam valve of a nuclear power turbine that can eliminate the failure of the drive mechanism to operate, in order to address the above-mentioned technical problems.

[0006] In a first aspect, this application provides a hydraulic control mechanism for the high-pressure steam valve of a nuclear power turbine. The hydraulic control mechanism for the high-pressure steam valve of a nuclear power turbine includes a first hydraulic channel, which includes: a first trip solenoid valve, a first pilot cartridge valve, a first main cartridge valve, and a first check valve.

[0007] The first end of the first trip solenoid valve is connected to the oil supply device through a return oil channel. The second end of the first trip solenoid valve is connected to the control oil chamber of the first pilot cartridge valve through a first throttle orifice. The second end of the first trip solenoid valve is also connected to the first end of the first check valve. The second end of the first check valve is connected to the pressure oil chamber of the first pilot cartridge valve. The second end of the first check valve is also connected to the first end of the first main cartridge valve. The second end of the first main cartridge valve is connected to the drive mechanism through a power channel. The first pilot cartridge valve and the first main cartridge valve are also connected to the oil supply device through return oil channels, respectively.

[0008] When the first trip solenoid valve is de-energized and closed, the first pilot cartridge valve and the first main cartridge valve open in sequence, forming an oil circuit from the drive mechanism to the oil supply device.

[0009] In one embodiment, the high-pressure steam valve hydraulic control mechanism of the nuclear power turbine further includes a first plug, which is embedded in the pipeline between the first trip solenoid valve and the first pilot cartridge valve, and the first end of the first plug has a first throttling orifice.

[0010] In one embodiment, a second throttle orifice is provided between the first end of the first trip solenoid valve and the oil supply device.

[0011] In one embodiment, the orifice diameter data corresponding to the first orifice is obtained by inputting the orifice diameter data of the second orifice and the pressure data corresponding to the first orifice into a preset orifice diameter calculation model. The orifice diameter calculation model includes flow constraint conditions, which are used to constrain the flow rate of the first orifice to be equal to or approximately equal to the flow rate of the second orifice.

[0012] In one embodiment, a sealing element is fitted onto the first end of the first plug, the sealing element being used to seal the first plug and the pipeline.

[0013] In one embodiment, the hydraulic control mechanism for the high-pressure steam valve of the nuclear power turbine further includes a second hydraulic channel, which includes: a second trip solenoid valve, a second pilot cartridge valve, a second main cartridge valve, and a second check valve;

[0014] The first end of the second trip solenoid valve is connected to the oil supply device through the return oil channel; the second end of the second trip solenoid valve is connected to the control oil chamber of the second pilot cartridge valve through the third throttle orifice; the second end of the second trip solenoid valve is also connected to the first end of the second check valve; the second end of the second check valve is connected to the pressure oil chamber of the second pilot cartridge valve; the second end of the second check valve is also connected to the first end of the second main cartridge valve; the second end of the second main cartridge valve is connected to the drive mechanism through the power channel; the second pilot cartridge valve and the second main cartridge valve are also respectively connected to the oil supply device through the return oil channel.

[0015] When the second trip solenoid valve is de-energized and closed, the second pilot cartridge valve and the second main cartridge valve open in sequence, forming an oil circuit from the drive mechanism to the oil supply device.

[0016] Secondly, this application also provides a high-pressure steam valve drive system for a nuclear power turbine, which includes an oil supply device, a drive mechanism, a power channel, a return oil channel, and a high-pressure steam valve hydraulic control mechanism for a nuclear power turbine as described in the first aspect.

[0017] The first end of the power channel is connected to the oil supply device, the second end of the power channel is connected to the drive mechanism, and the third end of the power channel is connected to the hydraulic control mechanism of the high-pressure steam valve of the nuclear power turbine.

[0018] One end of the oil return channel is connected to the oil supply device, and the other end of the oil return channel is connected to the hydraulic control mechanism, drive mechanism and power channel of the high-pressure steam valve of the nuclear power turbine, respectively.

[0019] The power channel is used to supply power oil to the drive mechanism when it is open to drive the drive mechanism to open, and to cut off the power oil when it is closed to shut down the drive mechanism.

[0020] In one embodiment, the system further includes a control channel, one end of which is connected to the oil supply device, and the other end of which is connected to the hydraulic control mechanism of the high-pressure steam valve of the nuclear power turbine.

[0021] In one embodiment, the power channel includes a switching element, a first end of which is connected to an oil supply device, and a second end of which is connected to a drive mechanism; the switching element is used to turn on or off the power channel.

[0022] Thirdly, this application also provides a nuclear power turbine unit, which includes the nuclear power turbine high-pressure steam valve drive system as described in the second aspect.

[0023] The aforementioned hydraulic control mechanism and drive system for the high-pressure steam valve of the nuclear power turbine, by setting a first throttle orifice between the second end of the first trip solenoid valve and the control oil chamber of the first pilot cartridge valve, ensures that the oil pressure in the control oil chamber of the first pilot cartridge valve is much greater than the oil pressure in the pressure oil chamber when the nuclear power turbine is tripped. During tripping, the first pilot cartridge valve can overcome the frictional forces of other factors. Thus, regardless of whether the first pilot cartridge valve is open or closed before the nuclear power turbine is tripped, it can ensure that the first pilot cartridge valve is closed. This eliminates the drive mechanism's failure to operate without affecting the nuclear power turbine's fast-closing function, or changing the original power channel, control logic, and system parameters of the high-pressure steam valve drive system, and eliminates the impact on the upward movement of the drive mechanism and the experimental impact during operation. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments of this application or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the structure of a high-pressure steam valve drive system for a nuclear power turbine in one embodiment;

[0026] Figure 2 This is a schematic diagram of the structure of the first hydraulic channel in one embodiment;

[0027] Figure 3(a) is a schematic cross-sectional view of the first plug in one embodiment;

[0028] Figure 3(b) is a magnified view of the part marked "A" in Figure 3(a);

[0029] Figure 3(c) is a magnified view of the part marked "B" in Figure 3(a);

[0030] Figure 4 This is a schematic diagram of the structure of the second hydraulic channel in one embodiment.

[0031] Figure label:

[0032] 1. Oil supply device; 2. Drive mechanism; 3. First hydraulic channel; 31. First trip solenoid valve; 32. First pilot cartridge valve; 33. First main cartridge valve; 34. First check valve; 35. First throttle orifice; 36. Second throttle orifice; 4. Second hydraulic channel; 41. Second trip solenoid valve; 42. Second pilot cartridge valve; 43. Second main cartridge valve; 44. Second check valve; 45. Third throttle orifice; 46. Fourth throttle orifice; 5. Switching element; 6. Power channel; 7. Oil return channel; 8. Control channel; 9. First plug; 91. Slot; 92. Annular step. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0034] It should be noted that the terms "first," "second," etc., used in this application can be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish the first element from the second element. The terms "comprising" and "having," and any variations thereof, used in this application, are intended to cover non-exclusive inclusion. The term "multiple" used in this application refers to two or more. The term "and / or" used in this application refers to one of the embodiments, or any combination of multiple embodiments.

[0035] Each failure to start of a 1,000-kilowatt nuclear power turbine occurs during the turbine's upward rotation. After a failure, a thorough inspection of the emergency shutdown components is required, with an estimated inspection and maintenance time of approximately 4 hours per occurrence. Therefore, each failure results in a loss of 4 million kilowatt-hours of electricity generation. During valve operation tests in normal operation, a failure to start will increase the time spent troubleshooting and equipment maintenance by approximately 10 hours per test. At this time, the unit's load is at 95% of full capacity, resulting in a loss of 500,000 kilowatt-hours of electricity generation. If a failure to start occurs during testing, coupled with abnormal flow control in the control system, the nuclear power turbine may trip due to pressure loss in the regulating oil system.

[0036] Traditional technologies for resolving drive mechanism failure in megawatt-class nuclear power turbines typically involve increasing the spring force of the pilot cartridge valve and shortening the valve cleaning cycle. Increasing the spring force alters the opening speed of the pilot cartridge valve, affecting the drive mechanism's quick-closing function. Furthermore, the increase in spring force is very limited; even if all the margin of spring force is added, it is still insufficient to counteract the resistance generated by the sludge that accumulates between the valve core and valve sleeve during operation. Therefore, the failure to completely eliminate the failure to operate is not possible. One way to shorten the cleaning cycle of cartridge valves is to reduce closing resistance by cleaning the sludge between the valve core and the valve sleeve, thus keeping the friction between the valve core and the valve sleeve at its optimal state. While this method can eliminate most failures to operate, it has two drawbacks: First, it increases maintenance workload. Each maintenance requires cleaning and inspecting the cartridge valves of each drive mechanism, costing approximately 4,000 yuan in labor and spare parts costs per valve. For each nuclear power turbine with 8 drive mechanisms and 16 pilot cartridge valves, the total cost is approximately 64,000 yuan. Second, excessive cleaning and polishing of the cartridge valves can cause them to deteriorate due to gaps, even after the same lifespan as the drive mechanism. The problem was that the unit was prematurely scrapped, requiring a cleaning and inspection process before the pilot cartridge valve was replaced. Each major overhaul cleaning and inspection involved a relatively large workload, severely impacting the overhaul period of the speed control system. Each additional day of overhaul time resulted in the unit generating 24 million kilowatt-hours less electricity. On the other hand, the potential for the drive mechanism to fail to operate could not be completely eliminated. During the cleaning cycle, a large amount of sludge might still be generated, causing the pilot cartridge valve to remain open before the unit was switched on. Furthermore, if abnormal problems such as water ingress into the system, localized high temperatures, internal leaks in the system, or component corrosion occur, the pilot cartridge valve might still fail to close when the unit is switched on, resulting in a failure to operate. Therefore, this potential failure to operate remains unresolved.

[0037] The high-pressure steam valve hydraulic control mechanism for nuclear power turbines provided in this application embodiment can be applied to, for example... Figure 1The diagram shows a high-pressure steam valve drive system for a nuclear power turbine. The system includes an oil supply device 1, a drive mechanism 2, a power channel 6, a return oil channel 7, and the high-pressure steam valve hydraulic control mechanism of the nuclear power turbine as described in this embodiment. The first end of the power channel 6 is connected to the oil supply device 1, the second end of the power channel 6 is connected to the drive mechanism 2, and the third end of the power channel 6 is connected to the high-pressure steam valve hydraulic control mechanism of the nuclear power turbine. One end of the return oil channel 7 is connected to the oil supply device 1, and the other end of the return oil channel 7 is connected to the high-pressure steam valve hydraulic control mechanism of the nuclear power turbine, the drive mechanism 2, and the power channel 6. The power channel 6 is used to supply power oil to the drive mechanism 2 when it is open to drive the drive mechanism 2 to open, and to cut off the power oil when it is closed to shut down the drive mechanism 2.

[0038] Among them, power channel 6, such as Figure 1 The red lines in the middle indicate the channels. When the power channel 6 is open, the power oil is transmitted from the oil supply device 1 to the drive mechanism 2 along the power channel 6 to drive the drive mechanism 2 to open; when the power channel 6 is closed, the power oil cannot be transmitted to the drive mechanism 2, causing the drive mechanism 2 to close.

[0039] Return oil channel 7 Figure 1 The green lines represent channels through which the power oil in the system can return to the oil supply device 1 via the return oil channel 7.

[0040] In an exemplary embodiment, the power channel 6 includes a switching element 5, the first end of which is connected to the oil supply device 1, and the second end of which is connected to the drive mechanism 2; the switching element 5 is used to control the power channel 6 to be turned on or off.

[0041] In some embodiments, the switching element 5 may be a switching solenoid valve or a servo valve.

[0042] In some embodiments, the third end of the switching element 5 is connected to the return oil passage 7. By closing the switching element 5, the power passage 6 is cut off, and the oil in the power passage 6 returns to the oil supply device 1 through the return oil passage 7.

[0043] In an exemplary embodiment, the nuclear power turbine high-pressure steam valve drive system provided in this application further includes a control channel 8. One end of the control channel 8 is connected to the oil supply device 1, and the other end is connected to the hydraulic control mechanism of the nuclear power turbine high-pressure steam valve. The high-pressure oil in the oil supply device 1 is divided into power oil and control oil. The power oil is transmitted along the power channel 6; the control oil is transmitted along the control channel 8. The control channel 8 is as follows... Figure 1 The blue lines represent the channels.

[0044] When the nuclear power turbine needs to be engaged, control oil is transmitted from the oil supply device 1 along the control channel 8 to the high-pressure steam valve hydraulic control mechanism of the nuclear power turbine. The high-pressure steam valve hydraulic control mechanism of the nuclear power turbine is used to cut off the drive mechanism 2 from the return oil channel 7, so that the drive mechanism 2 can be controlled to open or close through the switching element 5 in the power channel 6.

[0045] When a nuclear power turbine malfunctions and needs to be shut down, the power oil used to drive the drive mechanism 2 will enter the return oil channel 7 through the hydraulic control mechanism of the high-pressure steam valve of the nuclear power turbine, and finally be discharged back into the oil supply device 1, so as to achieve the purpose of quickly closing the steam valve to cut off the steam source and stop the nuclear power turbine from running.

[0046] In one exemplary embodiment, see Figure 1 and Figure 2 A hydraulic control mechanism for high-pressure steam valves of a nuclear power turbine is provided. This mechanism includes a first hydraulic channel 3, which comprises a first trip solenoid valve 31, a first pilot cartridge valve 32, a first main cartridge valve 33, and a first check valve 34. The first end of the first trip solenoid valve 31 is connected to an oil supply device 1 via a return oil channel 7. The second end of the first trip solenoid valve 31 is connected to the control oil chamber of the first pilot cartridge valve 32 via a first throttle orifice 35. The second end of the first trip solenoid valve 31 is also connected to the first end of the first check valve 34. The second end of the first check valve 34 is connected to the pressure oil chamber of the first pilot cartridge valve 32. The second end of the first check valve 34 is also connected to the first end of the first main cartridge valve 33. The second end of the first main cartridge valve 33 is connected to a drive mechanism 2 via a power channel 6. The first pilot cartridge valve 32 and the first main cartridge valve 33 are also connected to the oil supply device 1 via the return oil channel 7.

[0047] Specifically, the first trip solenoid valve 31 is also connected to the oil supply device 1 through the control channel 8; the first trip solenoid valve 31 is connected to the first pilot cartridge valve 32 and the first trip solenoid valve 31 is connected to the first main cartridge valve 33 through the control channel 8.

[0048] Both the first check valve 34 and the first throttle orifice 35 are located on the control channel 8. It can be understood that there is only one first check valve 34 between the control oil chamber and the pressure oil chamber of the first pilot cartridge valve 32. Figure 2 In the control channel 8, the control oil flows from port X to port A and is in a flowing state, but cannot flow from port A to port X.

[0049] In conjunction with the aforementioned embodiments, when a nuclear power turbine malfunctions and requires shutdown, the first trip solenoid valve 31 is de-energized and closed, while the first pilot cartridge valve 32 and the first main cartridge valve 33 open sequentially, forming an oil circuit from the drive mechanism 2 to the oil supply device 1. Specifically, the first trip solenoid valve 31 in the first hydraulic channel 3 is de-energized and closed, the first pilot cartridge valve 32 opens, and the control oil in the control oil chamber and pressure oil chamber of the first pilot cartridge valve 32 is quickly discharged back to the oil supply device 1 through the return oil channel 7. The first main cartridge valve 33 also opens after the first pilot cartridge valve 32 opens, and the control oil in the first main cartridge valve 33 is discharged back to the oil supply device 1 through the return oil channel 7. Finally, the power oil in the power channel 6 that drives the drive mechanism 2 also flows through the opened first main cartridge valve 33 and is discharged back to the oil supply device 1 through the return oil channel 7, achieving the purpose of quickly closing the steam valve, cutting off the steam source, and stopping the nuclear power turbine.

[0050] When the nuclear power turbine needs to be tripped, the first trip solenoid valve 31 is energized and opened in the first hydraulic channel 3. Control oil will enter the first trip solenoid valve 31 along the control channel 8, then enter the control oil chamber of the first pilot cartridge valve 32 to close it, and then enter the pressure oil chamber of the first pilot cartridge valve 32 and the control oil chamber of the first main cartridge valve 33 to close the first main cartridge valve 33. The drive mechanism 2 is cut off from the return oil channel 7, so that the drive mechanism 2 can be controlled to open or close by the switching element 5 in the power channel 6.

[0051] In this embodiment, the control oil in the control channel 8 passes through the first trip solenoid valve 31, then through the first throttle orifice 35 into the control oil chamber of the first pilot cartridge valve 32, and through the first check valve 34 into the pressure oil chamber of the first pilot cartridge valve 32. Because the effective area of ​​the control oil chamber of the first pilot cartridge valve 32 in existing nuclear power turbine units is larger than that of the pressure oil chamber, the entire tripping process is a process of synchronous pressure increase at port X and port A of the first pilot cartridge valve 32. Due to the area difference, the hydraulic pressure in the control oil chamber of the first pilot cartridge valve 32 is greater than that in the pressure oil chamber. The first throttle orifice 35 cuts off the leakage, creating an oil pressure difference between port X and port A, making the pressure at port X higher than that at port A, thus adding extra closing force to the first pilot cartridge valve 32 and ensuring successful tripping of the nuclear power turbine.

[0052] In this embodiment, a first throttle orifice 35 is added between the control oil chamber and the pressure oil chamber of the first pilot cartridge valve 32 and before the first check valve 34. Compared with the embodiment without the first throttle orifice, when the nuclear power turbine needs to be tripped, the oil supply speed of the oil supply device to the control oil chamber of the first pilot cartridge valve 32 via the first trip solenoid valve 31 through the control channel 8 is slowed down. The time to fill the oil and depressurize the chamber is slightly longer for the same volume of chamber, but this has no impact on the actual control of the drive mechanism 2. When the nuclear power turbine needs to be tripped, the oil in the control oil chamber and the pressure oil chamber of the first pilot cartridge valve 32 can be quickly discharged back to the oil supply device 1 through the return channel 7, without being restricted by the first throttle orifice 35 and thus not affecting the return time. It can be seen that adding the first throttle orifice 35 has no impact on the tripping operation and valve closing time of the nuclear power turbine. The high-pressure valve hydraulic control mechanism of the nuclear power turbine in this embodiment does not affect the fast-closing function of the nuclear power turbine.

[0053] The aforementioned hydraulic control mechanism for the high-pressure steam valve of the nuclear power turbine, by setting a first throttle orifice 35 between the second end of the first trip solenoid valve 31 and the control oil chamber of the first pilot cartridge valve 32, ensures that the oil pressure in the control oil chamber of the first pilot cartridge valve 32 is much greater than the oil pressure in the pressure oil chamber when the nuclear power turbine is tripped. During tripping, the first pilot cartridge valve 32 can overcome the frictional forces of other factors. Thus, regardless of whether the first pilot cartridge valve 32 is in an open or closed state before the nuclear power turbine is tripped, it can ensure that the first pilot cartridge valve 32 is closed. This eliminates the failure of the drive mechanism 2 to move without affecting the fast-closing function of the nuclear power turbine, without changing the original power channel design, control logic and system parameters of the high-pressure steam valve drive system of the nuclear power turbine, and eliminates the impact on the upward movement of the drive mechanism 2 and the test impact during operation.

[0054] Figure 3(a) shows a cross-sectional view of the first plug in one embodiment of this application; Figure 3(b) is a partial enlarged view marked "A" in Figure 3(a); Figure 3(c) is a partial enlarged view marked "B" in Figure 3(a). Referring to Figure 3(a), in an exemplary embodiment, the hydraulic control mechanism of the high-pressure steam valve of the nuclear power turbine further includes a first plug, which is embedded in the pipeline between the first trip solenoid valve 31 and the first pilot cartridge valve 32, and the first end of the first plug is provided with a first throttling orifice 35.

[0055] The first end of the first plug 9, as shown in the enlarged view marked "A" in Figure 3(a) and Figure 3(b), has a groove 91 at its first end, which can be used to accommodate a sealing element. For example, the width of the groove 91 can be 2 mm, and the surface roughness of the side and bottom of the groove 91 can be 1.6 μm.

[0056] In some embodiments, a partially enlarged view of the second end of the first plug 9 is shown in Figure 3(c). The second end of the first plug is provided with an annular step 92. In the view of Figure 3(c), the left side of the annular step 92 is a right angle, and the right side is a chamfer. The annular step 92 can be used to fit a sealing element, which is used to seal the first plug and the pipeline. The sealing element is positioned between the right angle and the chamfer.

[0057] In some embodiments, the second end of the first plug is further provided with an external thread, the specification of which can be G1 / 4-19.

[0058] For example, the outer diameter of the first end of the first plug can be 11.8 mm, and the outer diameter of the second end of the first plug can be 18.9 mm.

[0059] In this embodiment, by opening a first throttling hole 35 on the first plug, the failure of the drive mechanism 2 to operate can be quickly eliminated without affecting the high-pressure steam valve drive system of the nuclear power turbine. The modification method is simple, the modification construction is easy, and it is easy to implement.

[0060] In one exemplary embodiment, see further... Figure 2 A second throttle orifice 36 is provided in the pipeline between the first end of the first trip solenoid valve 31 and the oil supply device 1.

[0061] In one possible implementation, the orifice diameter of the first throttling orifice 35 is in the range of 0.7-0.85 mm; the orifice diameter of the second throttling orifice 36 is 0.8 mm.

[0062] In an exemplary embodiment, the orifice diameter data d1 corresponding to the first orifice 35 is obtained by inputting the orifice diameter data d2 of the second orifice 36 and the pressure data P0 corresponding to the second orifice 36 into a preset orifice diameter calculation model. The orifice diameter calculation model includes flow constraint conditions, which are used to constrain the flow rate of the first orifice 35 to be equal to or approximately equal to the flow rate of the second orifice 36.

[0063] The pressure data corresponding to the second throttling orifice 36 refers to the upstream pressure P0 of the second throttling orifice 36 and the pressure P between the first throttling orifice 35 and the second throttling orifice 36. m .

[0064] For example, the orifice diameter of the pipe containing the first orifice 35 and the second orifice 36 can be 12 mm, the orifice diameter d2 of the second orifice 36 can be 0.8 mm, P0 = 16 MPa, and the fluid in the pipe is an incompressible liquid. The flow constraint condition can be expressed as:

[0065]

[0066] in, It is the flow coefficient. P1 is the fluid density, and P2 is the pressure after the first orifice 35. After processing the flow constraint, it can be further expressed as:

[0067]

[0068] In principle, return oil channel 7 has a 6-bar check valve. However, in actual operation, due to the very small internal leakage of the drive mechanism and the internal leakage of the check valve, there is basically no accumulation of fire-resistant oil in return oil channel 7. Therefore, return oil channel 7 can be considered as atmospheric pressure, and the pressure P2 after the first throttle orifice 35 can be considered as atmospheric pressure. With d2 = 0.8 mm, P0 = 16 MPa, and P2 = 0.1 MPa, the final ratio is as follows:

[0069] ,

[0070] With the first pilot cartridge valve 32 having a core diameter of 16mm and the high-pressure regulating valve having a core diameter of 25mm, and a first throttling orifice 35 of 0.8mm selected, the first pilot cartridge valve 32 generates a closing force of 1280N, and the high-pressure regulating valve's pilot cartridge valve generates a closing force of 2000N. This is far greater than the spring force and sludge resistance of the first pilot cartridge valve 32, ensuring that no failure to operate due to sludge resistance will occur during the maintenance cycle of the drive mechanism 2.

[0071] In this embodiment, the orifice diameter data of the second orifice 36 and the pressure data corresponding to the second orifice 36 are used to calculate the orifice diameter data of the first orifice 35. This allows for a quick and easy determination of the size of the first orifice 35, ensuring a sufficiently large pressure difference between the control oil chamber and the pressure oil chamber of the first pilot cartridge valve 32. This prevents malfunctions or failures to operate and improves the reliability of the hydraulic control mechanism for the high-pressure steam valve of the nuclear power turbine.

[0072] In one exemplary embodiment, see Figure 4The hydraulic control mechanism for the high-pressure steam valve of the nuclear power turbine also includes a second hydraulic channel 4, which includes: a second trip solenoid valve 41, a second pilot cartridge valve 42, a second main cartridge valve 43, and a second check valve 44. The first end of the second trip solenoid valve 41 is connected to the oil supply device 1 through the return oil channel 7, and the second end of the second trip solenoid valve 41 is connected to the control oil chamber of the second pilot cartridge valve 22 through the third throttle orifice 45. The second end of the second trip solenoid valve 41 is also connected to the first end of the second check valve 44. The second end of the second check valve 44 is connected to the pressure oil chamber of the second pilot cartridge valve 42, and the second end of the second check valve 44 is also connected to the first end of the second main cartridge valve 43. The second end of the second main cartridge valve 43 is connected to the drive mechanism 2 through the power channel 6. The second pilot cartridge valve 42 and the second main cartridge valve 43 are also connected to the oil supply device 1 through the return oil channel 7, respectively.

[0073] When the second trip solenoid valve 41 is de-energized and closed, the second pilot cartridge valve 42 and the second main cartridge valve 43 open in sequence, forming an oil circuit from the drive mechanism 2 to the oil supply device 1.

[0074] The second hydraulic channel 4 is a hydraulic channel connected in parallel with the first hydraulic channel 3. The structure of the second hydraulic channel 4 can be referred to the description of the first hydraulic channel 3 in the above embodiments.

[0075] When the nuclear power turbine needs to be tripped, for the second hydraulic channel 4, control oil will also enter the second trip solenoid valve 41 along the control channel 8, then enter the control oil chamber of the second pilot cartridge valve 42 to close it, and then enter the pressure oil chamber of the second pilot cartridge valve 42 and the control oil chamber of the second main cartridge valve 43 to close the second main cartridge valve 43. In this way, the drive mechanism 2 is isolated from the return oil channel 7 by the first main cartridge valve 33 and the second main cartridge valve 43, and the drive mechanism 2 can be controlled to open or close by the switching element 5 in the power channel 6.

[0076] In some embodiments, if the equipment in the first hydraulic channel 3 or the second hydraulic channel 4 fails to operate, the first trip solenoid valve 31 or the second trip solenoid valve 41 can still be shut off individually, causing the control oil in the corresponding first pilot cartridge valve 32 or the second pilot cartridge valve 42 to be quickly discharged. The control oil in the first main cartridge valve 33 or the second main cartridge valve 43 is also discharged back to the oil supply device 1 after the first pilot cartridge valve 32 or the second pilot cartridge valve 42 is opened. Finally, the pressure oil of the drive mechanism 2 is also discharged into the return oil channel 7, achieving the purpose of closing the steam valve to cut off the steam source and stop the nuclear power turbine from operating.

[0077] In this embodiment, the first hydraulic channel 3 and the second hydraulic channel 4 connected in parallel can complete the depressurization and quick-closing actions of the drive mechanism 2 in parallel or independently, ensuring that the hydraulic control mechanism of the high-pressure steam valve of the nuclear power turbine can still work reliably and safely in the face of a single point of failure.

[0078] In one exemplary embodiment, the high-pressure steam valve hydraulic control mechanism of a nuclear power turbine includes a first hydraulic channel 3 and a second hydraulic channel 4.

[0079] The first hydraulic channel 3 includes: a first trip solenoid valve 31, a first pilot cartridge valve 32, a first main cartridge valve 33, and a first check valve 34. The first end of the first trip solenoid valve 31 is connected to the oil supply device 1 through the return oil channel 7. The second end of the first trip solenoid valve 31 is connected to the control oil chamber of the first pilot cartridge valve 32 through the first throttle orifice 35. The second end of the first trip solenoid valve 31 is also connected to the first end of the first check valve 34. The second end of the first check valve 34 is connected to the pressure oil chamber of the first pilot cartridge valve 32. The second end of the first check valve 34 is also connected to the first end of the first main cartridge valve 33. The second end of the first main cartridge valve 33 is connected to the drive mechanism 2 through the power channel 6. The first pilot cartridge valve 32 and the first main cartridge valve 33 are also connected to the oil supply device 1 through the return oil channel 7, respectively. When the first trip solenoid valve 31 is de-energized and closed, the first pilot cartridge valve 32 and the first main cartridge valve 33 open sequentially, forming an oil passage from the drive mechanism 2 to the oil supply device 1. A second throttle orifice 36 is provided in the pipeline between the first end of the first trip solenoid valve 31 and the oil supply device 1.

[0080] The second hydraulic channel 4 includes: a second trip solenoid valve 41, a second pilot cartridge valve 22, a second main cartridge valve 43, and a second check valve 44; the first end of the second trip solenoid valve 41 is connected to the oil supply device 1 through the return oil channel 7, the second end of the second trip solenoid valve 41 is connected to the control oil chamber of the second pilot cartridge valve 22 through the third throttle orifice 45, and the second end of the second trip solenoid valve 41 is also connected to the first end of the second check valve 44; the second end of the second check valve 44 is connected to the second pilot cartridge valve 22. The pressure oil chamber is connected, and the second end of the second check valve 44 is also connected to the first end of the second main cartridge valve 43; the second end of the second main cartridge valve 43 is connected to the drive mechanism 2 through the power channel 6; the second pilot cartridge valve 22 and the second main cartridge valve 43 are also connected to the oil supply device 1 through the return oil channel 7 respectively; when the second trip solenoid valve 41 is de-energized and closed, the second pilot cartridge valve 22 and the second main cartridge valve 43 open in sequence to form an oil circuit from the drive mechanism 2 to the oil supply device 1.

[0081] The hydraulic control mechanism for the high-pressure steam valve of the nuclear power turbine also includes a first plug 9 and a second plug. The first plug 9 is embedded in the pipeline between the first trip solenoid valve 31 and the first pilot cartridge valve 32, and a first throttling orifice 35 is provided at the first end of the first plug 9. A sealing element is fitted at the second end of the first plug 9 to seal the first plug 9 and the pipeline. The second plug is embedded in the pipeline between the second trip solenoid valve 41 and the second pilot cartridge valve 22, and a third throttling orifice 45 is provided at the first end of the second plug. A fourth throttling orifice 46 is provided in the pipeline between the first end of the second trip solenoid valve 41 and the oil supply device 1. A sealing element is fitted at the second end of the second plug to seal the second plug and the pipeline. The orifice diameters of the first and third throttling orifices range from 0.7 to 0.85 mm; the orifice diameters of the second and fourth throttling orifices are 0.8 mm.

[0082] The orifice diameter data corresponding to the first orifice 35 is obtained by inputting the orifice diameter data and pressure data corresponding to the second orifice 36 into a preset orifice diameter calculation model. The orifice diameter calculation model includes flow constraint conditions, which are used to ensure that the flow rate of the first orifice 35 is equal to or approximately equal to the flow rate of the second orifice 36. Similarly, the orifice diameter data corresponding to the third orifice 45 is obtained by inputting the orifice diameter data and pressure data corresponding to the fourth orifice 46 into the orifice diameter calculation model.

[0083] The high-pressure steam valve hydraulic control mechanism of the nuclear power turbine in this embodiment can be tested through simulation model to detect the outlet pressure and valve core displacement of the first pilot cartridge valve 32, the first main cartridge valve 33, the second pilot cartridge valve 42, and the second main cartridge valve 43. Through simulation experiment, the high-pressure steam valve hydraulic control mechanism of the nuclear power turbine in this embodiment can achieve effective pressure build-up, thereby eliminating the failure of the drive mechanism 2 to operate without affecting the fast closing function of the nuclear power turbine, without changing the original power channel, control logic, and system parameters of the high-pressure steam valve drive system of the nuclear power turbine, and eliminating the impact on the upward movement of the drive mechanism 2 and the test impact during operation.

[0084] The high-pressure steam valve hydraulic control mechanism for nuclear power turbines provided in this embodiment can be applied to the high-pressure steam valve drive system of nuclear power turbines, and can also be extended to other similar drive systems.

[0085] In the description of this specification, the references to terms such as "some embodiments," "other embodiments," "ideal embodiments," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example that are included in at least one embodiment or example of this application. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0086] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.

[0087] The above embodiments are merely illustrative of several implementation methods of this application, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A hydraulic control mechanism for high-pressure steam valves of a nuclear power turbine, characterized in that, The high-pressure steam valve hydraulic control mechanism of the nuclear power turbine includes a first hydraulic channel, which includes: a first trip solenoid valve, a first pilot cartridge valve, a first main cartridge valve, and a first check valve. The first end of the first trip solenoid valve is connected to the oil supply device through a return oil channel; the second end of the first trip solenoid valve is connected to the control oil chamber of the first pilot cartridge valve through a first throttle orifice; the second end of the first trip solenoid valve is also connected to the first end of the first check valve; the second end of the first check valve is connected to the pressure oil chamber of the first pilot cartridge valve; the second end of the first check valve is also connected to the first end of the first main cartridge valve; the second end of the first main cartridge valve is connected to the drive mechanism through a power channel; the first pilot cartridge valve and the first main cartridge valve are also respectively connected to the oil supply device through return oil channels. When the first trip solenoid valve is de-energized and closed, the first pilot cartridge valve and the first main cartridge valve open in sequence, forming an oil circuit from the drive mechanism to the oil supply device; A second throttling orifice is provided in the pipeline between the first end of the first trip solenoid valve and the oil supply device. The high-pressure steam valve hydraulic control mechanism of the nuclear power turbine also includes a second hydraulic channel, which includes: a second trip solenoid valve, a second pilot cartridge valve, a second main cartridge valve, and a second check valve. The first end of the second trip solenoid valve is connected to the oil supply device through a return oil channel; the second end of the second trip solenoid valve is connected to the control oil chamber of the second pilot cartridge valve through a third throttle orifice; the second end of the second trip solenoid valve is also connected to the first end of the second check valve; the second end of the second check valve is connected to the pressure oil chamber of the second pilot cartridge valve; the second end of the second check valve is also connected to the first end of the second main cartridge valve; the second end of the second main cartridge valve is connected to the drive mechanism through a power channel; the second pilot cartridge valve and the second main cartridge valve are also respectively connected to the oil supply device through return oil channels. When the second trip solenoid valve is de-energized and closed, the second pilot cartridge valve and the second main cartridge valve open in sequence, forming an oil circuit from the drive mechanism to the oil supply device.

2. The hydraulic control mechanism for high-pressure steam valves of a nuclear power turbine according to claim 1, characterized in that, The high-pressure steam valve hydraulic control mechanism of the nuclear power turbine also includes a first plug, which is embedded in the pipeline between the first trip solenoid valve and the first pilot cartridge valve, and the first end of the first plug is provided with the first throttling orifice.

3. The hydraulic control mechanism for high-pressure steam valves of a nuclear power turbine according to claim 1, characterized in that, The orifice diameter data corresponding to the first throttling orifice is obtained by inputting the orifice diameter data of the second throttling orifice and the pressure data corresponding to the second throttling orifice into a preset orifice diameter calculation model. The orifice diameter calculation model includes flow constraint conditions, which are used to constrain the flow rate of the first throttling orifice to be equal to or approximately equal to the flow rate of the second throttling orifice.

4. The hydraulic control mechanism for high-pressure steam valves of a nuclear power turbine according to claim 2, characterized in that, A sealing element is fitted onto the second end of the first plug, and the sealing element is used to seal the first plug and the pipeline.

5. A high-pressure steam valve drive system for a nuclear power turbine, characterized in that, The nuclear power turbine high-pressure steam valve drive system includes an oil supply device, a drive mechanism, a power channel, an oil return channel, and the nuclear power turbine high-pressure steam valve hydraulic control mechanism as described in any one of claims 1-4. The first end of the power channel is connected to the oil supply device, the second end of the power channel is connected to the drive mechanism, and the third end of the power channel is connected to the hydraulic control mechanism of the high-pressure steam valve of the nuclear power turbine. One end of the oil return channel is connected to the oil supply device, and the other end of the oil return channel is connected to the hydraulic control mechanism of the high-pressure steam valve of the nuclear power turbine and the drive mechanism, respectively. The power channel is used to supply power oil from the oil supply device to the drive mechanism when it is open to drive the drive mechanism to open, and to cut off the power oil when it is closed to shut down the drive mechanism.

6. The high-pressure steam valve drive system for nuclear power turbines according to claim 5, characterized in that, The system also includes a control channel, one end of which is connected to the oil supply device, and the other end of which is connected to the hydraulic control mechanism of the high-pressure steam valve of the nuclear power turbine.

7. The high-pressure steam valve drive system for nuclear power turbines according to claim 5, characterized in that, The power channel includes a switching element, the first end of which is connected to the oil supply device, and the second end of which is connected to the drive mechanism; The switching element is used to control the power channel to be turned on or off.

8. A nuclear power turbine unit, characterized in that, The nuclear power turbine unit includes the high-pressure steam valve drive system for nuclear power turbines as described in any one of claims 5-7.

Images