Pump cover for seawater circulating pump

Abstract

The utility model discloses a pump cover for a seawater circulating pump, and relates to the field of nuclear power equipment.The pump cover comprises a cover plate and a transmission shaft penetrating through the middle of the cover plate, heat conduction pipes for heat conduction penetrate through the interior of the cover plate at equal intervals in a surrounding mode, and one ends of the heat conduction pipes are located on the outer surface of the cover plate; and a heat conducting plate attached to the mechanical sealing surface is fixedly arranged at the other end. Cooling water is prevented from making contact with the mechanical seal directly through metal heat conduction, so that the mechanical seal can be effectively protected, and meanwhile the service life of the mechanical seal is prolonged.

Description

Technical Field

[0001] The present application relates to the field of nuclear power equipment, and in particular to a pump cover for a seawater circulation pump. Background Art

[0002] The PCS recirculation pump is a recirculation pump commonly used in the PCS system of nuclear power plants. The PCS system is also called the passive containment cooling system. The function of this system is to remove the heat from the containment, reduce the temperature and pressure of the containment, reduce the pressure difference between the containment atmosphere and the external environment, and limit the release of radioactive materials after the accident when the loss of coolant (LOCA) or main steam line rupture (MSLB) accident occurs in the containment. PCS is also used as the replenishment water source for the spent fuel pool. The main components of the PCS system include: passive containment cooling water storage tank (PCCWST), air baffle, air inlet and air outlet, and water distribution system. In addition, there is a passive containment cooling auxiliary water storage tank (PCCAWST) and two PCS recirculation pumps. The PCS recirculation pump is used on site to provide additional cooling water from the PCCAWST to the PCS system, and can also provide backup water for the earthquake-resistant water tower of the fire protection system.

[0003] For example, the pump cover for a PCS recirculation pump in patent number CN202597249U has the following deficiencies in actual use:

[0004] The above patent achieves the cooling effect by directing water to the mechanical seal surface of the PCS recirculation pump, but water is corrosive to a certain extent and the introduction of water increases the risk of water leakage in the pump body and increases the probability of damage to the pump body. Utility Model Content

[0005] In order to improve the cooling effect of the mechanical sealing surface, the present application provides a pump cover for a seawater circulation pump.

[0006] The present application provides a pump cover for a seawater circulation pump adopts the following technical solution:

[0007] A pump cover for a seawater circulation pump comprises a cover plate and a transmission shaft penetrating the middle of the cover plate, wherein heat-conducting pipes for heat conduction are equidistantly penetrated around the interior of the cover plate, one end of the heat-conducting pipe is located on the outer surface of the cover plate, and the other end is fixed with a heat-conducting plate that fits the mechanical sealing surface.

[0008] By adopting the above technical solution, the heat conducting plate transfers heat to the heat conducting pipe, and the low-temperature end and the high-temperature end of the heat conducting pipe exchange heat, thereby achieving a cooling effect.

[0009] Preferably, the cover plate is provided with a mounting groove for inserting the mechanical seal in the middle of one end of the heat conducting plate, and the inner wall of the mounting groove abuts against the heat conducting plate.

[0010] By adopting the above technical solution, the abutment between the heat conducting plate and the mounting groove can improve the cooling effect, so that the cover plate also participates in the cooling. Since the thermal conductivity of air is poor, abutment for heat conduction is required.

[0011] Preferably, one end of the heat conducting plate extends to the end of the mounting groove, and the heat conducting plate is configured to be arc-shaped.

[0012] By adopting the above technical solution, the heat conducting plate is preferably made of copper material. At the same time, the coverage of the heat conducting plate and the mechanical seal needs to be set according to actual conditions to avoid interference between the heat conducting plate and the surface structure of the mechanical seal and affect the rotation.

[0013] Preferably, the inner wall of the cover plate is equidistantly provided with installation pipe grooves for the heat-conducting pipes to pass through, and the installation pipe grooves are connected to the installation grooves.

[0014] By adopting the above technical solution, the installation pipe groove can fix the heat pipe to prevent it from shaking due to vibration. At the same time, the heat on the surface of the heat pipe can also be transferred to the surface of the cover plate for auxiliary heat dissipation.

[0015] Preferably, an outer side of the cover plate at one end away from the mounting groove is arranged as an inclined surface.

[0016] By adopting the above technical solution, the setting of the inclined surface facilitates the installation of the cover plate.

[0017] Preferably, the installation pipe groove is arranged around the middle of the inclined surface and enables the installation pipe groove to communicate with the outside.

[0018] By adopting the above technical solution, the pipe groove is installed to be connected with the outside world so that one end of the heat conduction pipe can be located in the water pressure chamber at the low temperature end.

[0019] Preferably, a plurality of capillaries are fixedly disposed on the inner surface of the heat conducting tube, and the heat conducting tube and the capillaries are both made of copper.

[0020] By adopting the above technical solution, the capillary tube can make the liquid flow to the high-temperature end under the action of capillary, thereby realizing circulating heat dissipation.

[0021] Preferably, the heat conducting pipe is filled with a small amount of heat absorbing liquid.

[0022] By adopting the above technical solution, the liquid absorbs heat and vaporizes, then dissipates heat and liquefies when it encounters cold, thereby achieving heat transfer and reducing the temperature of the mechanical seal.

[0023] In summary, the present application includes at least one of the following beneficial technical effects:

[0024] 1. Use heat pipes and heat conduction plates to transfer most of the heat of the mechanical seal to the water in the water pressure chamber, thereby achieving a rapid cooling effect. This method uses hard heat dissipation to effectively prevent the mechanical seal from being corroded by liquid and increase its service life;

[0025] 2. With the help of heat conduction plates and heat conduction pipes, part of the heat is transferred to the cover plate to assist in heat dissipation and further improve the heat dissipation and cooling effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is an overall axonometric diagram of the cover plate of the present application;

[0027] Figure 2 This is a schematic cross-sectional view of the cover plate of the present application;

[0028] Figure 3 A schematic diagram of the installation slot for this application;

[0029] Figure 4 A schematic diagram of the heat conducting plate and the mounting slot of the present application;

[0030] Figure 5 Schematic diagram of the capillary tube of this application.

[0031] Figure numerals: 1. cover plate; 2. inclined plane; 3. transmission shaft; 4. heat pipe; 5. mechanical seal; 6. heat conducting plate; 7. mounting groove; 8. mounting pipe groove; 9. capillary tube. DETAILED DESCRIPTION

[0032] The following is combined with Figure 1 —5 Provide further details of this application.

[0033] An embodiment of the present application discloses a pump cover for a seawater circulation pump.

[0034] Example 1

[0035] Reference Figure 1-4A pump cover for a seawater circulation pump comprises a cover plate 1 and a through hole in the middle of the cover plate 1, a transmission shaft 3 movably penetrates the through hole, the transmission shaft 3 is a part of the seawater circulation pump, and mounting pipe grooves 8 are equidistantly arranged around the inner wall of the cover plate 1, and a heat conducting pipe 4 is plugged and fixed inside the mounting pipe groove 8. It should be noted that the mounting pipe groove 8 should be arranged to avoid the groove on the surface of the cover plate 1 to avoid the heat conducting pipe 4 affecting the installation of the cover plate 1, thereby causing other structures to need to be re-arranged to adapt to the cover plate 1, thereby causing the volume of the circulation pump to change, the inner cavity of the mounting pipe groove 8 is communicated with the mounting groove 7, and the outer edge of the outer side of the cover plate 1 away from the end of the mounting groove 7 is arranged as an inclined slope 2, and the inclination angle of the slope 2 is consistent with the patent number CN202597249U The parts are arranged in the same way and will not be described in detail. The mounting pipe groove 8 is arranged in the middle of the inclined surface 2. The mounting pipe groove 8 and the mounting groove 7 are connected to the outside world. One end of the heat pipe 4 is inserted into the mounting pipe groove 8 of the cover plate 1, and one end of the heat pipe 4 extends out of the mounting pipe groove 8 and extends to the outer surface of the cover plate 1. It should be noted that whether one end of the heat pipe 4 extends out of the mounting pipe groove 8 needs to be arranged according to actual needs. Because one side of the cover plate 1 is arranged in the water pressure chamber, the heat pipe 4 can also be arranged in the mounting pipe groove 8. At the same time, the mounting pipe groove 8 and the surface of the heat pipe 4 are sealed by glue to prevent the water in the water pressure chamber from entering the mounting groove 7. A heat conducting plate 6 is fixed to the other end of the heat pipe 4, and the surface of the heat conducting plate 6 is in contact with the surface of the mechanical seal 5.

[0036] Through the above arrangement, the mechanical seal generates heat and transfers the heat to the heat conducting plate 6. The heat conducting plate 6 can transfer the heat to the cover plate 1 itself and one end of the heat conducting pipe 4 located in the water pressure chamber, and realize heat exchange with the heat conducting pipe 4 through the water inside the water pressure chamber, thereby cooling the heat conducting pipe 4 and cooling the mechanical seal 5. At the same time, the heat conducting plate 6 can surround the surface of the mechanical seal 5 to increase the heat conducting area and achieve better cooling effect, effectively prolonging the service life of the mechanical seal 5, and further improving the heat dissipation effect of the mechanical seal 5 through the auxiliary heat dissipation of the cover plate 1 itself.

[0037] Please refer to Figures 2 and 3. The cover plate 1 is provided with a mounting groove 7 in the middle of one end of the heat conducting plate 6. A mechanical seal 5 is fixed in the mounting groove 7. The mounting method of the mechanical seal 5 is the same as that of the cited patent document, so it will not be described in detail. The inner wall of the mounting groove 7 abuts against the surface of the heat conducting plate 6 to achieve a better heat conducting effect.

[0038] Please refer to Figure 5A plurality of capillaries 9 are fixedly arranged on the inner surface of the heat-conducting tube 4, and the capillaries 9 cover the inner wall of the heat-conducting tube 4. The heat-conducting tube 4 and the capillaries 9 are preferably made of copper, which has good thermal conductivity, and other materials with better thermal conductivity can also be selected. The inside of the heat-conducting tube 4 is filled with a small amount of heat-absorbing liquid, which can be alcohol, methanol or pure water, etc., mainly to achieve heat absorption and vaporization and then liquefaction when cooled, thereby realizing heat transportation and improving the cooling effect.

[0039] The implementation principle of a pump cover for a seawater circulation pump in an embodiment of the present application is as follows: after the cover plate 1 is installed, as the movable end of the mechanical seal 5 continues to rotate, its end face will generate high temperature, and the generated heat is first transferred to the heat conducting plate 6, and the heat conducting plate 6 transfers part of the heat to the cover plate 1 for cooling, and transfers the other part of the heat to the heat conducting pipe 4. When the evaporation end of the heat pipe is heated, the working medium in the pipe, such as alcohol, Freon, ammonia water, etc., begins to absorb heat and undergo a phase change, from liquid to steam. This process consumes a large amount of heat, thereby playing a role in reducing the temperature of the heated end. The steam generates a pressure difference in the heat pipe, driving the steam to move to the cooling end called the condensation end.

[0040] In this process, the steam takes away a large amount of heat, allowing the heat to be transferred quickly. When the steam reaches the condensation end, due to the low ambient temperature, the steam will lose heat and condense into a liquid working medium. This process will release heat equal to the heat absorbed during evaporation. When the steam condenses into liquid at the condensation end, the liquid will quickly penetrate into the capillary 9.

[0041] Then, under the capillary force of the capillary tube 9, the liquid working medium will flow back to the evaporation end along the porous material to prepare for the next round of evaporation process.

[0042] The heat pipe 4 can also be replaced by a heat pipe in the prior art.

[0043] In summary, the device directly avoids the contact between cooling water and the mechanical seal 5 through metal heat conduction, thereby effectively protecting the mechanical seal 5 and increasing the service life of the mechanical seal 5.

[0044] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A pump cover for a seawater circulation pump, comprising a cover plate (1) and a transmission shaft (3) penetrating the middle of the cover plate (1), characterized in that: Heat-conducting pipes (4) for heat conduction are equidistantly arranged around the interior of the cover plate (1); one end of the heat-conducting pipe (4) is located on the outer surface of the cover plate (1), and the other end is fixedly provided with a heat-conducting plate (6) that is in contact with the surface of the mechanical seal (5).

2. A pump cover for a seawater circulation pump according to claim 1, characterized in that: The cover plate (1) is provided with a mounting groove (7) for inserting the mechanical seal (5) at the middle of one end of the heat conducting plate (6), and the inner wall of the mounting groove (7) is in contact with the heat conducting plate (6).

3. A pump cover for a seawater circulation pump according to claim 2, characterized in that: One end of the heat conducting plate (6) extends to the end of the mounting groove (7), and the heat conducting plate (6) is arranged in an arc shape.

4. A pump cover for a seawater circulation pump according to claim 1, characterized in that: The inner wall of the cover plate (1) is equidistantly provided with installation pipe grooves (8) for the heat conduction pipes (4) to pass through, and the installation pipe grooves (8) are connected to the installation grooves (7).

5. A pump cover for a seawater circulation pump according to claim 4, characterized in that: An outer end of the cover plate (1) away from the mounting groove (7) is provided with an inclined surface (2).

6. A pump cover for a seawater circulation pump according to claim 4, characterized in that: The installation pipe groove (8) is arranged around the middle of the inclined surface (2) and enables the installation pipe groove (8) to communicate with the outside.

7. A pump cover for a seawater circulation pump according to claim 1, characterized in that: A plurality of capillaries (9) are fixedly arranged on the inner surface of the heat conducting tube (4), and the heat conducting tube (4) and the capillaries (9) are both made of copper.

8. The pump cover for a seawater circulation pump according to claim 1, characterized in that: The interior of the heat conducting pipe (4) is filled with a small amount of heat absorbing liquid.

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