Water-water high-energy reactor three-generation nuclear power unit equipment cooling water pump

Abstract

The utility model relates to a kind of water-water high-energy reactor three-generation nuclear power unit equipment cooling water pump, the cooling water pump is horizontal double-suction centrifugal pump with middle opening, the cooling water pump includes: stator component, rotor component, driving end bearing body component, non-driving end bearing body component, shaft seal component, instrument control component, auxiliary pipe component, rotor component includes pump shaft, pump shaft is along the horizontal midplane and passes through stator component, driving end bearing body component and non-driving end bearing body component are respectively located at the two sides of rotor component, shaft seal component is container type mechanical seal, it is symmetrically arranged to locate stator component two sides, instrument control component and auxiliary pipe component are installed on stator component.The utility model whole structure is reasonable, wall thickening, shaft thickening, pressure-bearing capacity is strong, rotor rigidity is high, corrosion and scouring resistance, impact resistance, adapt to impurity condition, half center foot support stability, vibration resistance is good;Axial force can be directional under all conditions, self-balancing, high reliability.

Description

Technical Field

[0001] This utility model relates to a cooling water pump, specifically a cooling water pump for a third-generation nuclear power unit of a water-to-water high-energy reactor that features a reasonable overall structure, strong pressure bearing capacity, high rotor rigidity, corrosion and erosion resistance, good support stability, good self-balancing ability, and high reliability. Background Technology

[0002] VVER (Water-Water Energy Reactor) third-generation nuclear power units are pressurized water reactor nuclear power units that are gradually being used more and more in the world.

[0003] The equipment cooling pump is a key component of the safety injection system in a pressurized water reactor nuclear power plant, classified as Nuclear Safety Level 3. Its function is to deliver equipment cooling water during normal operation, shutdown, and various accident conditions of the nuclear power plant, for cooling safety-related equipment in the nuclear island system (including nuclear auxiliary systems and dedicated safety systems). The medium transported by the equipment cooling pump is SED water + trisodium phosphate demineralized water, which contains phosphates, chlorides, fluorides, and suspended solids. The pump has multiple design operating points, and its performance curve requires a steep drop. The pump is required to have strong pressure resistance, low rotor deflection, corrosion resistance, erosion resistance, and impact resistance.

[0004] The existing equipment's cooling water pump has thin walls and weak pressure resistance. The shaft sleeve makes the shaft diameter smaller and causes large deflection. The impeller generates large axial forces with irregular directions. The pump is supported by the pump's feet, resulting in poor stability due to its high center. The pump core assembly cannot be hoisted and removed as a whole, which is a drawback in terms of maintenance convenience. On-site management relies on manual monitoring, which cannot monitor temperature rise and vibration in real time. There are no collection facilities for exhaust, drainage, and sewage, which have an adverse impact on the on-site environment. Utility Model Content

[0005] To address the aforementioned problems, the main objective of this utility model is to provide a cooling water pump for third-generation nuclear power units in water-to-water high-energy reactors that features a reasonable overall structure, strong pressure-bearing capacity, high rotor rigidity, corrosion and erosion resistance, good support stability, good self-balancing ability, and high reliability.

[0006] This utility model solves the above-mentioned technical problems through the following technical solution: a cooling water pump for a water-to-water high-energy reactor third-generation nuclear power unit, wherein the cooling water pump is a horizontal split-case double-suction centrifugal pump, and the cooling water pump includes: a stator assembly, a rotor assembly, a drive-end bearing assembly, a non-drive-end bearing assembly, a shaft seal assembly, an instrumentation and control assembly, and an auxiliary pipe assembly; the rotor assembly includes a pump shaft that passes through the stator assembly along a horizontal split plane; the drive-end bearing assembly and the non-drive-end bearing assembly are respectively located on both sides of the rotor assembly; the shaft seal assembly is a cartridge mechanical seal, symmetrically arranged on both sides of the stator assembly; the instrumentation and control assembly and the auxiliary pipe assembly are mounted on the stator assembly; the entire cooling water pump is fixedly mounted on a pump base.

[0007] In a specific embodiment of this utility model, the rotor component includes a pump shaft, a double-suction impeller, a key, an impeller nut, a water baffle ring, a positioning bushing, an angular contact ball bearing, a left oil slinger bushing, a first small round nut, a cylindrical roller bearing, a right oil slinger bushing, a second small round nut, a pump coupling, a locking washer, and a third small round nut.

[0008] The double-suction impeller is fitted onto the pump shaft and key, and is locked and positioned using two impeller nuts; the double-suction impeller flow channels are arranged symmetrically along the center.

[0009] The double-suction impeller has large and small inlet rings on both sides of the center of the flow channel; the small inlet ring is located on the left side of the impeller; the large inlet ring is located on the right side of the impeller.

[0010] The left side of the rotor assembly is the non-drive end, which consists of a water baffle ring, a positioning sleeve, two back-to-back angular contact ball bearings, and a left oil slinger sleeve, which are sequentially fitted onto the pump shaft; the back-to-back angular contact ball bearings are locked and positioned by two first small round nuts.

[0011] The right side of the rotor assembly is the drive end, which consists of a water baffle ring, a positioning bushing, a cylindrical roller bearing, and a right oil slinger bushing, which are sequentially fitted onto the pump shaft. The cylindrical roller bearing is locked and positioned by two second small round nuts.

[0012] The pump coupling is fitted into the tapered hole on the right side of the pump shaft and is locked and positioned by a retaining washer and a third small round nut.

[0013] First, fit the oil slinger ring onto the right oil slinger sleeve on the right side of the rotor assembly. Then, connect the drive end bearing housing assembly to the cylindrical roller bearing of the rotor assembly, place it on the right side support frame of the pump body, and connect and tighten it with multiple pairs of studs, nuts and elastic washers.

[0014] Next, insert the oil slinger ring onto the left oil slinger ring sleeve on the left side of the rotor assembly. Then, connect the back-to-back two angular contact ball bearings of the non-drive end bearing body assembly and the rotor assembly, place them on the left side support frame of the pump body, and connect and tighten them with multiple pairs of studs, nuts and elastic washers.

[0015] In a specific embodiment of this utility model, the stator component includes: a pump cover, a pump body, and an intermediate sealing gasket. The intermediate sealing gasket is located between the pump cover and the pump body. The pump cover and the pump body are connected and fastened by multiple sets of main studs and main nuts.

[0016] In a specific embodiment of this utility model, both the non-driving end bearing body component and the driving end bearing body component are provided with an oil slinger ring, a stop bar, an automatic exhaust valve, and a lifting ring.

[0017] In a specific embodiment of this utility model, the drive end bearing body component includes a drive end bearing body; the non-drive end bearing body includes a non-drive end bearing body; both the drive end bearing body and the non-drive end bearing body are provided with instrument interfaces for mounting instrument control components.

[0018] In specific embodiments of this utility model, the positive and progressive effects of this utility model are as follows: The cooling water pump for third-generation nuclear power units in water-to-water high-energy reactors provided by this utility model has the following advantages: The overall structure of this utility model is reasonable, with thickened walls and a thickened shaft, resulting in strong pressure bearing capacity, high rotor rigidity, corrosion and erosion resistance, impact resistance, and adaptability to working conditions containing impurities. The semi-center foot support provides good stability and vibration resistance; under all working conditions, axial force can be oriented, self-balanced, and highly reliable. During maintenance, there is no need to disassemble the pipeline; simply loosen the main nut, first lift the pump cover, and then lift the core assembly, including the rotor components, bearing body components, and sealing components, out of the housing cavity for repair or replacement, reducing maintenance time; it has intelligent instrumentation and monitoring, facilitating on-site management; and it is equipped with auxiliary pipe components for centralized liquid drainage treatment, improving the on-site operating environment. Attached Figure Description

[0019] Figure 1 This is one of the structural schematic diagrams of this utility model.

[0020] Figure 2 This is the second structural schematic diagram of the present invention.

[0021] Figure 3 This is a partial structural diagram of the present invention (pear-shaped cavity portion).

[0022] Figure 4 This is another partial structural diagram of the present invention (rotor component part). Detailed Implementation

[0023] The preferred embodiments of this utility model are given below with reference to the accompanying drawings to illustrate the technical solution of this utility model in detail.

[0024] Figure 1 This is one of the structural schematic diagrams of this utility model. Figure 2 This is the second structural schematic diagram of the present invention. Figure 3 This is a partial structural diagram of the present invention (pear-shaped cavity portion). Figure 4 The following is a partial structural schematic diagram of the present invention (rotor component part), as shown in the figure above: The cooling water pump of the third-generation nuclear power unit equipment of the water-water high-energy reactor proposed in this invention is a horizontal split-case double-suction centrifugal pump. The cooling water pump includes: stator component, rotor component, bearing body component, shaft seal component, pump base, instrumentation and control component, auxiliary pipe component, etc.

[0025] The stator component 100 of the pump includes a pump body 101 and a pump cover 102. The pump body 101 and the pump cover 102 form a pressure-bearing housing. In the specific implementation process, its pressure-bearing wall is thickened to enhance the pressure-bearing capacity.

[0026] The stator component 100 of the pump is mounted on the pump base 1 by a semi-center foot provided on the pump body 101, and is connected and fastened by four sets of studs 2, nuts 3 and flat washers 4; the pump support is moved to the semi-center, which can improve the stability of the pump.

[0027] The stator component 100 of the pump has a pressure-bearing housing cavity composed of the pump body 101 and the pump cover 102. The housing cavities on both sides are connected to the inlet pipe 110, and the inlet pipe and the pump stator are provided with a first channel 111. The housing cavity in the middle is connected to the outlet pipe 120, and the outlet pipe and the pump stator are provided with a second channel 121.

[0028] The stator component 100 of the pump is divided into a pump cover 102, a pump body 101, and an intermediate sealing gasket 103 along the horizontal axis, and is connected and fastened by multiple sets of main studs 104 and main nuts 105.

[0029] The bearing housing components include a drive-end bearing housing component 300 and a non-drive-end bearing housing component 400.

[0030] On both sides of the stator component 100 of the pump, the right pump body 101 is provided with a bracket on which the drive end bearing component 300 is installed; the left pump body 101 is provided with a bracket on which the non-drive end bearing component 400 is installed.

[0031] The pump stator assembly 100 has a core package assembly that can be installed and lifted out as a whole in the mounting cavity. The core package assembly includes a rotor assembly 200, a drive end bearing body assembly 300 and a non-drive end bearing body assembly 400, a shaft seal assembly 600 and a pump coupling 501. After loosening the main nut 105, the pump cover 102 can be moved away, and the core package assembly can be lifted out of the mounting cavity as a whole for maintenance or replacement.

[0032] The rotor component 200 can rotate within the mounting cavity and is supported by the drive end bearing component 300 and the non-drive end bearing component 400. The drive end bearing component 300 is fitted with a (radial) cylindrical roller bearing 210, and the non-drive end bearing component 400 is fitted with two (radial + thrust) angular contact ball bearings 207.

[0033] The rotor assembly 200 includes a pump shaft 201, a double-suction impeller 202, a key 203, an impeller nut 204, a water baffle ring 205, a positioning bushing 206, an angular contact ball bearing 207, a left oil slinger ring bushing 208, a first small round nut 209, a cylindrical roller bearing 210, a right oil slinger ring bushing 211, a second small round nut 212, a pump coupling 501, a locking washer 213, and a third small round nut 214.

[0034] The pump 201 shaft passes through the stator component 100 along the horizontal split plane; and the outer diameter of the pump shaft 201 is thickened to improve rigidity and reduce shaft deflection.

[0035] The double-suction impeller 202 is sleeved on the pump shaft 201 and key 203, and is locked and positioned by two impeller nuts 204; and the flow channel of the double-suction impeller 202 is arranged symmetrically along the center, and has the function of axial force self-balancing.

[0036] Among them, the double suction impeller 202 is provided with large and small inlet rings on the left and right sides of the flow channel center; the small inlet ring is located on the left side of the impeller; the large inlet ring is located on the right side of the impeller; the impeller is provided with large and small inlet rings, which can realize an axial force directed to the right side, so that the shaft is always under tension and improves the shaft rigidity.

[0037] The left side of the rotor component 200 is the non-drive end, which is connected to the pump shaft 201 in sequence by a water baffle ring 205, a positioning sleeve 206, two angular contact ball bearings 207, and a left oil slinger sleeve 208. The back-to-back angular contact ball bearings 207 are locked and positioned by two first small round nuts 209. The combination of two back-to-back angular contact ball bearings can withstand bidirectional axial force, radial force, and overturning force.

[0038] The right side of the rotor component 200 is the drive end, which is connected to the pump shaft 201 in sequence by a water baffle ring 205, a positioning sleeve 206, a cylindrical roller bearing 210, and a right oil slinger sleeve 211. The cylindrical roller bearing 210 is locked and positioned by two second small round nuts 212. The cylindrical roller bearing is used to bear the radial force.

[0039] The pump coupling 501 is sleeved with the right tapered hole of the pump shaft 201 and is locked and positioned by the stop washer 213 and the third small round nut 214. The tapered hole connection allows for convenient and quick disassembly of the pump coupling.

[0040] First, an oil slinger 5 is fitted onto the right oil slinger sleeve 211 on the right side of the rotor component 200. Then, the drive end bearing body component 300 is fitted onto the cylindrical roller bearing 210 of the rotor component 200 and placed on the right side support frame of the pump body 101. It is then connected and secured by multiple pairs of studs 9, nuts 10 and elastic washers 11.

[0041] First, an oil slinger 5 is fitted onto the left oil slinger sleeve 208 on the left side of the rotor component 200. Then, the non-drive end bearing body component 400 is fitted onto the two angular contact ball bearings 207 of the rotor component 200 and placed on the left support frame of the pump body 101. It is then connected and fastened by multiple pairs of studs 6, nuts 7 and elastic washers 8.

[0042] The drive-end bearing body component 300 includes a drive-end bearing body 301; the non-drive-end bearing body component 400 includes a non-drive-end bearing body 401; both the drive-end bearing body 301 and the non-drive-end bearing body 401 are provided with instrument interface mounting instrument control components.

[0043] The instrumentation and control components include a temperature measurement and control component 700 and a vibration measurement and control component 800, which enable real-time monitoring of the pump unit's operation and facilitate on-site management.

[0044] The shaft seal component 600 includes a cartridge mechanical seal, which is symmetrically arranged on both sides of the stator component.

[0045] The auxiliary pipe components include an exhaust component 12, a drainage component 13, a sewage collection tray 14, and a sewage pipe 15, which are used to collect drainage and sewage to improve the user's on-site environment.

[0046] The following is the specific working process of this utility model:

[0047] During operation, the medium enters the same suction chambers (112 and 113 in the figure) on both sides of the stator component 100 through the first channel 111 of the pump inlet pipe 110, and flows into the inlets on both sides of the double suction impeller 202. The rotational torque is transmitted through the pump coupling 501, which causes the entire rotor component 200 to drive the double suction impeller 202 to rotate and do work. Under the action of centrifugal force, the energy of the liquid medium is increased, and it flows out through the intermediate volute pear-shaped cavity 122 into the second channel pump outlet pipe 121.

[0048] Since the flow channels of the double-suction impeller 202 are symmetrically arranged on both sides of the center line A, the hydraulic forces on both sides are theoretically equal in magnitude, thus possessing axial force self-balancing capability. However, due to casting, machining, and other errors, unbalanced forces exist in actual applications, and their direction cannot be determined. Therefore, large and small inlet rings are provided on the left and right sides of the double-suction impeller 202 along the center line A of the flow channels. The small inlet ring is located on the left side of the impeller, and the large inlet ring is located on the right side of the impeller, realizing an axial force oriented to the right side, so that the shaft 201 is always in a tensile state, increasing the rigidity of the rotor component 200; structurally, this improves the operational reliability of this type of pump.

[0049] To further improve the operational reliability of the rotor assembly 200, the left side of the rotor assembly 200 adopts a combination of two back-to-back angular contact ball bearings 207 to withstand bidirectional axial force, radial force and overturning force, and eliminate residual axial force and overturning force; structurally, this further improves the operational reliability of this type of pump.

[0050] Instrument interfaces are provided on the drive end bearing housing 301 of the drive end bearing housing component 300 and the non-drive end bearing housing 401 of the non-drive end bearing housing component 400. Temperature measuring instrument control component 700 and vibration measuring instrument control component 800 are installed on both to realize real-time monitoring of pump unit operation and facilitate on-site management.

[0051] The equipment's cooling water pump is also equipped with an exhaust component 12, a drainage component 13, a sewage collection component 14, and a sewage pipe 15, forming a drainage and sewage collection device to improve the user's on-site environment.

[0052] This utility model offers a rationally designed structure with thickened walls for increased pressure resistance, a thickened shaft for high rigidity, corrosion and erosion resistance, impact resistance, and adaptability to conditions containing impurities. The semi-center foot support provides good stability and low vibration. Axial force is oriented, self-balancing, and highly reliable under all operating conditions. During maintenance, there is no need to disassemble the pipeline; simply loosen the main nut, lift the pump cover, and then lift the entire core assembly (including the rotor, bearing housing, and sealing components) out of the mounting cavity for repair or replacement, minimizing maintenance time. It features intelligent instrumentation and monitoring for convenient on-site management. An auxiliary pipe assembly is provided for centralized liquid drainage, improving the on-site operating environment.

[0053] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of protection of this utility model as defined by the appended claims and their equivalents.

Claims

1. A cooling water pump for a third-generation nuclear power unit in a water-to-water high-energy reactor, characterized in that: The cooling water pump for the third-generation water-to-water high-energy reactor is a horizontal split-case double-suction centrifugal pump. The cooling water pump includes: a stator assembly, a rotor assembly, a drive-end bearing housing assembly, a non-drive-end bearing housing assembly, a shaft seal assembly, an instrumentation and control assembly, and auxiliary pipe assemblies. The rotor assembly includes a pump shaft that passes through the stator assembly along a horizontal split plane. The drive-end and non-drive-end bearing housing assemblies are located on opposite sides of the rotor assembly. The shaft seal assembly is a cartridge mechanical seal, symmetrically arranged on both sides of the stator assembly. The instrumentation and control assembly and auxiliary pipe assemblies are mounted on the stator assembly. The entire cooling water pump is fixedly mounted on a pump base.

2. The cooling water pump for a third-generation high-energy reactor nuclear power unit according to claim 1, characterized in that: The rotor assembly includes a pump shaft, a double-suction impeller, a key, an impeller nut, a water baffle ring, a positioning bushing, an angular contact ball bearing, a left oil slinger bushing, a first small round nut, a cylindrical roller bearing, a right oil slinger bushing, a second small round nut, a pump coupling, a locking washer, and a third small round nut. The double-suction impeller is fitted onto the pump shaft and key, and is locked and positioned using two impeller nuts; the double-suction impeller flow channels are arranged symmetrically along the center. The double-suction impeller has large and small inlet rings on both sides of the center of the flow channel; the small inlet ring is located on the left side of the impeller; the large inlet ring is located on the right side of the impeller. The left side of the rotor assembly is the non-drive end, which consists of a water baffle ring, a positioning sleeve, two back-to-back angular contact ball bearings, and a left oil slinger sleeve, which are sequentially fitted onto the pump shaft; the back-to-back angular contact ball bearings are locked and positioned by two first small round nuts. The right side of the rotor assembly is the drive end, which consists of a water baffle ring, a positioning bushing, a cylindrical roller bearing, and a right oil slinger bushing, which are sequentially fitted onto the pump shaft. The cylindrical roller bearing is locked and positioned by two second small round nuts. The pump coupling is fitted into the tapered hole on the right side of the pump shaft and is locked and positioned by a stop washer and a third small round nut. First, put the oil slinger ring on the right oil slinger ring bushing on the right side of the rotor assembly. Then, connect the drive end bearing housing assembly with the cylindrical roller bearing of the rotor assembly, place it on the right side support frame of the pump body, and connect and tighten it with multiple pairs of studs, nuts and elastic washers. Next, insert the oil slinger ring onto the left oil slinger ring sleeve on the left side of the rotor assembly. Then, connect the back-to-back two angular contact ball bearings of the non-drive end bearing body assembly and the rotor assembly, place them on the left side support frame of the pump body, and connect and tighten them with multiple pairs of studs, nuts and elastic washers.

3. The cooling water pump for a third-generation high-energy reactor nuclear power unit according to claim 1, characterized in that: The stator components include: pump cover, pump body, and intermediate sealing gasket. The intermediate sealing gasket is located between the pump cover and the pump body. The pump cover and the pump body are connected and fastened by multiple sets of main studs and main nuts.

4. The cooling water pump for a third-generation high-energy reactor nuclear power unit according to claim 1, characterized in that: Both the non-drive end bearing body component and the drive end bearing body component are equipped with an oil slinger ring, a stop bar, an automatic exhaust valve, and a lifting ring.

5. The cooling water pump for a third-generation high-energy reactor nuclear power unit according to claim 1, characterized in that: The drive-end bearing housing component includes a drive-end bearing housing; the non-drive-end bearing housing includes a non-drive-end bearing housing; both the drive-end bearing housing and the non-drive-end bearing housing are provided with instrument interfaces for mounting instrument control components.

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