Throttling type pit filtering mechanism and pit filter

Abstract

The utility model belongs to the technical field of nuclear power station filtering instruments, and particularly relates to a throttling type pit filtering mechanism and a pit filter. The throttling type pit filtering mechanism comprises an outer filtering cylinder and an inner filtering cylinder installed in the outer filtering cylinder, the inner filtering cylinder comprises a first inner cylinder body, an inner Venturi cylinder body and a second inner cylinder body which are coaxially connected in sequence, and first inner filtering holes are fully distributed in the outer wall of the first inner cylinder body; and second inner filtering holes are fully distributed in the outer wall of the second inner cylinder body. According to the throttling type pit filtering mechanism disclosed by the utility model, when seawater flows in the inner filtering cylinder, the flow speed of the seawater passing through the inner Venturi cylinder body is increased, so that the water flow speed in the inner filtering cylinder is greater than the water flow speed outside the outer filtering cylinder, and the pressure difference between the inside and the outside of the throttling type pit filtering mechanism is increased; impurities and the like are not easy to block in the filter holes of the inner filter cartridge and the outer filter cartridge, so that the water supply efficiency of the nuclear power station is ensured.

Description

Technical Field

[0001] The utility model belongs to the technical field of nuclear power plant filtering equipment, in particular to a throttling type pit filtering mechanism and a pit filter. Background Art

[0002] A pit located at the bottom of the reactor containment vessel of a pressurized water reactor (PWR) nuclear power plant is used to collect coolant from the primary circuit in the event of a major leak. Following a baseline accident (such as a coolant loss accident or a main steam line rupture) at a PWR plant, coolant enters the containment pit through the breach. This coolant is filtered through the containment pit filter and then pumped through other devices to the safety injection system and safety spray system before being used to cool the reactor, preventing serious damage to the core and overpressure in the containment vessel.

[0003] Therefore, the containment pit filter is a critical component of the safety system of a pressurized water reactor nuclear power plant. Its performance under circulating conditions directly impacts the proper functioning of the safety injection and safety spray systems. Following an accident, the coolant entering the containment pit is contaminated with large amounts of insulation and other material fragments. These fragments must be removed by the pit filter to ensure the safe operation of the safety injection and containment spray systems.

[0004] Conventional pit filters consist of an outer filter cylinder and an inner filter cylinder mounted within it. Seawater is filtered through both the outer and inner filter cylinders before being fed into the nuclear power plant. However, since the flow rate of seawater through the outer and inner filter cylinders remains constant during filtration, impurities can easily clog the outer and inner filter cylinders, impacting the plant's water supply efficiency. Summary of the Invention

[0005] The utility model aims to solve the technical problem in the prior art that an outer filter cartridge and an inner filter cartridge are easily blocked by impurities during the process of filtering seawater, and provides a throttling type pit filter mechanism and a pit filter.

[0006] In view of the above technical problems, an embodiment of the present utility model provides a throttling type pit filter mechanism, including an outer filter cartridge and an inner filter cartridge installed in the outer filter cartridge, the inner filter cartridge including a first inner cylinder body, an inner venturi cylinder body and a second inner cylinder body coaxially connected in sequence, the outer wall of the first inner cylinder body is covered with first inner filter holes, and the outer wall of the second inner cylinder body is covered with second inner filter holes.

[0007] Optionally, the outer filter cylinder includes a first outer cylinder, an outer venturi cylinder and a second outer cylinder coaxially connected in sequence, the outer wall of the first outer cylinder is covered with first outer filter holes, and the outer wall of the second outer cylinder is covered with second outer filter holes.

[0008] Optionally, the first inner cylinder and the first outer cylinder are coaxially arranged, the inner venturi cylinder and the outer venturi cylinder are coaxially arranged, and the second inner cylinder and the second outer cylinder are coaxially arranged.

[0009] Optionally, the throttling pit filter mechanism is covered with an end cover on the outer filter cylinder, and the end cover is provided with a plurality of third filter holes.

[0010] Optionally, a mounting plate is provided on the outer wall of the outer filter cartridge at one end away from the end cover.

[0011] Optionally, a support plate is provided on the inner wall of the end of the outer filter cylinder away from the end cover, and the end of the second inner cylinder away from the inner venturi cylinder abuts against the support plate.

[0012] Another embodiment of the present invention further provides a pit filter, comprising a box body provided with a through hole and a plurality of the above-mentioned throttling type pit filter mechanisms; the outer filter cartridge is mounted on the box body, and the second inner hole of the inner filter cartridge is connected to the through hole.

[0013] Optionally, a mounting plate is provided on the outer wall of the outer filter cartridge away from the end cover, and a plurality of side grooves are further provided on the side wall of the box body, and the mounting plates are installed in the side grooves in a one-to-one correspondence.

[0014] Optionally, a first flange and a second flange are respectively provided at opposite ends of the box body, and the first flange and the second flange are both provided around the through hole.

[0015] In the present invention, a throttling pit filter mechanism includes an outer filter cartridge and an inner filter cartridge installed in the outer filter cartridge, the inner filter cartridge includes a first inner cylinder body, an inner venturi cylinder body and a second inner cylinder body coaxially connected in sequence; the throttling pit filter mechanism is installed in the seawater along the direction of the water flow, and the seawater enters the second inner hole of the inner filter cartridge after being filtered by the outer filter cartridge. During the flow of the seawater in the inner filter cartridge, the flow velocity of the seawater when passing through the inner venturi cylinder body will increase, so that the water flow velocity in the inner filter cartridge is greater than the water flow velocity outside the outer filter cartridge, thereby increasing the pressure difference between the inside and outside of the throttling pit filter mechanism, and impurities are not easily clogged in the filter holes of the inner filter cartridge and the outer filter cartridge, thereby ensuring the water supply efficiency of the nuclear power plant. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0017] Figure 1 is a structure schematic view of the throttling type floor pit filtering mechanism provided by an embodiment of the present utility model;

[0018] Figure 2 is a sectional view of the throttling type floor pit filtering mechanism provided by an embodiment of the present utility model;

[0019] Figure 3 is a structure schematic view of the end cover of the floor pit filter provided by an embodiment of the present utility model;

[0020] Figure 4 is a structure schematic view of the floor pit filter provided by an embodiment of the present utility model;

[0021] Figure 5 is a structure schematic view of the box body of the floor pit filter provided by an embodiment of the present utility model.

[0022] The reference signs in the specification are as follows:

[0023] 1, throttling type floor pit filtering mechanism;11, outer filter cylinder;111, first outer cylinder body;1111, first outer filter hole;112, outer texturizing cylinder body;113, second outer cylinder body;1131, second outer filter hole;114, mounting plate;115, support plate;12, inner filter cylinder;121, first inner cylinder body;1211, first inner filter hole;122, inner texturizing cylinder body;123, second inner cylinder body;1231, second inner filter hole;13, end cover;131, third filter hole;2, box body;21, through hole;22, side recess;23, first flange;24, second flange. DETAILED DESCRIPTION

[0024] In order to make the technical problems, technical schemes and beneficial effects solved by the present utility model more clearly understood, the present utility model will be further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present utility model, and are not used to limit the present utility model.

[0025] It should be understood that the terms "upper", "lower", "left", "right", "front", "back", "middle" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only used to facilitate the description of the present utility model and simplify the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present utility model.

[0026] As Figure 1 and Figure 2As shown, one embodiment of the present invention provides a throttling pit filter mechanism 1, comprising an outer filter cartridge 11 and an inner filter cartridge 12 mounted within the outer filter cartridge 11. The inner filter cartridge 12 comprises a first inner cylinder 121, an inner venturi cylinder 122, and a second inner cylinder 123 coaxially connected in sequence. The outer wall of the first inner cylinder 121 is covered with first inner filter holes 1211, and the outer wall of the second inner cylinder 123 is covered with second inner filter holes 1231. It is understood that both the inner filter cartridge 12 and the outer filter cartridge 11 are covered with filter holes; the first inner cylinder 121, the inner venturi cylinder 122, and the second inner cylinder 123 are integrally formed.

[0027] In the present invention, a throttling pit filter mechanism 1 includes an outer filter cartridge 11 and an inner filter cartridge 12 installed in the outer filter cartridge 11, wherein the inner filter cartridge 12 includes a first inner cylinder 121, an inner venturi cylinder 122 and a second inner cylinder 123 which are coaxially connected in sequence; the throttling pit filter mechanism 1 is installed in the seawater along the direction of the water flow, and the seawater enters the second inner hole of the inner filter cartridge 12 after being filtered by the outer filter cartridge 11. During the flow of the seawater in the inner filter cartridge 12, the flow velocity of the seawater when passing through the inner venturi cylinder 122 will increase, so that the water flow velocity in the inner filter cartridge 12 is greater than the water flow velocity outside the outer filter cartridge 11, thereby increasing the pressure difference between the inside and outside of the throttling pit filter mechanism 1, and impurities are not easily clogged in the filter holes of the inner filter cartridge 12 and the outer filter cartridge 11, thereby ensuring the water supply efficiency of the nuclear power plant.

[0028] In one embodiment, if Figures 1 to 3 As shown, the outer filter cartridge 11 comprises a first outer cylinder 111, an outer venturi cylinder 112, and a second outer cylinder 113, which are coaxially connected in sequence. The outer wall of the first outer cylinder 111 is covered with first outer filter holes 1111, and the outer wall of the second outer cylinder 113 is covered with second outer filter holes 1131. Preferably, the inner diameter of the first outer filter holes 1111 is larger than the inner diameter of the first inner filter holes 1211; and the inner diameter of the second outer filter holes 1131 is larger than the inner diameter of the second inner filter holes 1231. It is understood that the first outer cylinder 111, the outer venturi cylinder 112, and the second outer cylinder 113 are integrally formed.

[0029] In this embodiment, when water flows between the outer filter cartridge 11 and the inner filter cartridge 12, due to the design of the outer venturi cylinder 112, the flow rate of water flowing through the outer venturi cylinder 112 is increased, further increasing the pressure difference between the inside and outside of the throttling pit filter mechanism 1, and further reducing the accident of blockage between the inner filter cartridge 12 and the outer filter cartridge 11.

[0030] In one embodiment, if Figure 1 and Figure 2 As shown, the first inner cylinder 121 and the first outer cylinder 111 are coaxially arranged, the inner venturi cylinder 122 and the outer venturi cylinder 112 are coaxially arranged, and the second inner cylinder 123 and the second outer cylinder 113 are coaxially arranged. It can be understood that the first outer cylinder 111 is sleeved on the outside of the first inner cylinder 121, the outer venturi cylinder 112 is sleeved on the outside of the inner venturi cylinder 122, and the second outer cylinder 113 is sleeved on the outside of the second inner cylinder 123.

[0031] In one embodiment, if Figure 1 and Figure 2 As shown, the throttling pit filter mechanism 1 is fitted with an end cap 13 on the outer filter cartridge 11. This end cap 13 is provided with a plurality of third filter holes 131. As can be understood, the end cap 13 fits over the top of the first outer cylinder 111. External water flows through the third filter holes 131 on the end cap 13 before entering the inner filter cartridge 12 and the inner bore of the outer filter cartridge 11. In this embodiment, the design of the end cap 13 further enhances the filtering effectiveness of the throttling pit filter mechanism 1.

[0032] In one embodiment, if Figure 1 and Figure 2 As shown, a mounting plate 114 is provided on the outer wall of the outer filter cartridge 11 at the end away from the end cap 13. It is understood that the mounting plate 114 extends toward the outside of the outer filter cartridge 11, and the outer filter cartridge 11 is mounted on the housing 2 via the mounting plate 114, thereby improving the convenience of assembly and disassembly of the throttling pit filter mechanism 1.

[0033] In one embodiment, if Figure 1 and Figure 2 As shown, a support plate 115 is provided on the inner wall of the end of the outer filter cartridge 11 away from the end cap 13, and the end of the second inner cylinder 123 away from the inner venturi cylinder 122 abuts against the support plate 115. It can be understood that the support plate 115 extends toward the interior of the outer filter cartridge 11 and can support the inner filter cartridge 12 from the bottom, ensuring the stability of the inner filter cartridge 12 installed in the outer filter cartridge 11.

[0034] like Figure 4As shown, another embodiment of the present invention further provides a pit filter, comprising a housing 2 having a through hole 21 and a plurality of the aforementioned throttling pit filter mechanisms 1; the outer filter cartridge 11 is mounted on the housing 2, and the second inner hole of the inner filter cartridge 12 is connected to the through hole 21. It is understood that the number of throttling pit filter mechanisms 1 mounted on the base housing 2 can be set according to actual needs; for example, 8, 10, or 12 throttling pit filter mechanisms 1 can be provided; the design of the plurality of throttling pit filter mechanisms 1 enables the pit filter to filter the flow rate of the medium to be filtered per unit time.

[0035] Specifically, after the seawater is filtered by the outer filter cartridge 11, it enters the second inner hole of the inner filter cartridge 12. During the flow of seawater in the inner filter cartridge 12, the flow rate of the seawater when passing through the inner venturi cylinder 122 will increase, so that the water flow rate in the inner filter cartridge 12 is greater than the water flow rate outside the outer filter cartridge 11, thereby increasing the pressure difference between the inside and outside of the throttling pit filter mechanism 1, and impurities are not easily blocked in the filter holes of the inner filter cartridge 12 and the outer filter cartridge 11. After passing through the inner hole of the second inner cylinder 123, the water flows into the through hole 21 of the box body 2, and the box body 2 can supply filtered seawater to the nuclear power plant, thereby ensuring the efficiency of the water supply to the nuclear power plant.

[0036] In one embodiment, if Figure 4 and Figure 5 As shown, it is characterized in that a mounting plate 114 is provided on the outer wall of the end of the outer filter cartridge 11 away from the end cover 13, and a plurality of side grooves 22 are further provided on the side wall of the housing 2, and the mounting plates 114 are mounted one by one in the side grooves 22. It can be understood that the mounting plates 114 are mounted in the side grooves 22, so that the mounting plates 114 can play the role of filling the side grooves 22, and the outer wall of the mounting plate 114 is flush with the outer wall of the housing 2, ensuring the stability of the throttling pit filter mechanism 1 mounted on the housing 2.

[0037] In one embodiment, if Figure 4 and Figure 5 As shown, the box body 2 is provided with a first flange 23 and a second flange 24 at opposite ends, respectively. Both the first flange 23 and the second flange 24 are disposed around the through hole 21. It is understood that the first flange 23 and the second flange 24 are disposed on the left and right ends of the box body 2, respectively. In this embodiment, the design of the first flange 23 and the second flange 24 facilitates connection between the box body 2 and external pipes.

[0038] The above is only an embodiment of the throttling type floor pit filter mechanism and the floor pit filter of the utility model, and is not used to limit the utility model, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model should be included in the protection scope of the utility model.

Claims

1. A throttling type pit filter mechanism, characterized in that: It includes an outer filter cartridge and an inner filter cartridge installed in the outer filter cartridge. The inner filter cartridge includes a first inner cylinder, an inner venturi cylinder and a second inner cylinder that are coaxially connected in sequence. The outer wall of the first inner cylinder is covered with first inner filter holes, and the outer wall of the second inner cylinder is covered with second inner filter holes.

2. The throttling type pit filter mechanism according to claim 1, characterized in that: The outer filter cylinder includes a first outer cylinder, an outer venturi cylinder and a second outer cylinder that are coaxially connected in sequence. The outer wall of the first outer cylinder is covered with first outer filter holes, and the outer wall of the second outer cylinder is covered with second outer filter holes.

3. The throttling type pit filter mechanism according to claim 2, characterized in that: The first inner cylinder and the first outer cylinder are coaxially arranged, the inner venturi cylinder and the outer venturi cylinder are coaxially arranged, and the second inner cylinder and the second outer cylinder are coaxially arranged.

4. The throttling pit filter mechanism according to claim 1, characterized in that: The throttling pit filter mechanism is covered with an end cover on the outer filter cylinder, and the end cover is provided with a plurality of third filter holes.

5. The throttling type pit filtering mechanism according to claim 4, characterized in that: A mounting plate is provided on the outer wall of the outer filter cartridge at one end away from the end cover.

6. The throttling type pit filtering mechanism according to claim 4, characterized in that: A support plate is provided on the inner wall of the end of the outer filter cylinder away from the end cover, and the end of the second inner cylinder away from the inner venturi cylinder abuts against the support plate.

7. The throttling pit filter mechanism according to claim 2, characterized in that: The inner diameter of the first outer filter hole is larger than the inner diameter of the first inner filter hole; the inner diameter of the second outer filter hole is larger than the inner diameter of the second inner filter hole.

8. A pit filter, characterized in that: It comprises a box body provided with a through hole and a plurality of throttling type pit filter mechanisms as described in any one of claims 4 to 7; the outer filter cartridge is mounted on the box body, and the second inner hole of the inner filter cartridge is connected to the through hole.

9. The pit filter according to claim 8, characterized in that A mounting plate is provided on the outer wall of the outer filter cartridge away from the end cover, and a plurality of side grooves are further provided on the side wall of the box body, and the mounting plates are mounted in the side grooves in a one-to-one correspondence.

10. The pit filter according to claim 8, characterized in that The opposite ends of the box body are respectively provided with a first flange and a second flange, and the first flange and the second flange are both arranged around the through hole.

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