Multistage orifice plate for draining main steam header of nuclear power plant

Abstract

The application relates to the technical field of nuclear power operation and maintenance, and particularly discloses a multistage orifice plate for draining the main steam mother pipe of a nuclear power plant, wherein a plurality of multistage orifice plates are arranged in the inside of a cylindrical main body from front to back; the multistage orifice plates are all circular plates with through holes processed in the middle and arranged in parallel with each other; installation grooves are processed on the outer wall of the cylindrical main body and correspond to the first-stage orifice plate and the last-stage orifice plate; and anti-skid rings are installed in the installation grooves. The device has a simple overall structure and is convenient to use.

Description

Technical Field

[0001] This invention belongs to the field of nuclear power operation and maintenance technology, specifically relating to a multi-stage orifice plate for draining the main steam header of a nuclear power plant. Background Technology

[0002] In actual drainage processes, the condensate drain pipes of the main steam header in nuclear power plants are prone to problems such as large pipe diameter, large pressure difference before and after the drain valve, and high flow velocity of the vapor-liquid two-phase medium after the valve. These problems can easily lead to significant pipe vibration, severe corrosion, frequent internal leakage defects in the valves, and noise during valve opening. Therefore, multi-stage orifice plates are usually required to drain unstable flow media. Existing multi-stage orifice plates used for condensate draining of the main steam header in nuclear power plants typically have a smooth external structure, which makes them difficult to move during actual installation and prone to sliding and misalignment.

[0003] Therefore, there is an urgent need to design a multi-stage orifice plate for draining the main steam header of a nuclear power plant to solve the above problems. Summary of the Invention

[0004] The purpose of this invention is to provide a multi-stage orifice plate for draining the main steam header of a nuclear power plant, which is easy to handle and install.

[0005] The technical solution of the present invention is as follows:

[0006] A multi-stage perforated plate for draining the main steam header of a nuclear power plant includes a cylindrical body, with multiple perforated plates arranged from front to back on the inner side of the cylindrical body.

[0007] The multi-stage perforated plates are all circular flat plates with through holes machined in the middle, and they are arranged in parallel to each other;

[0008] On the outer wall of the cylindrical body, at positions corresponding to the first-stage and last-stage perforated plates, mounting grooves are machined respectively, and anti-slip rings are installed inside the mounting grooves.

[0009] A central strip is machined on the outer wall of the cylindrical body, between the two mounting slots.

[0010] The central strip is arranged along the axial direction of the cylindrical body and is distributed circumferentially on the outer wall of the cylindrical body.

[0011] The cylindrical main body is integrally formed with the multi-stage perforated plate and the central strip.

[0012] Rounded transitions are machined on the front and rear sides of the first-stage and last-stage perforated plates, at the junctions with the inner wall of the cylindrical body.

[0013] At the front and back sides of each perforated plate and at the junction with the inner wall of the cylindrical body, rounded transitions are machined.

[0014] Both ends of the cylindrical body are machined with 45° chamfers.

[0015] The multi-stage perforated plate has holes whose diameters gradually increase from front to back.

[0016] The multi-stage orifice plate includes a primary orifice plate, a secondary orifice plate, and a tertiary orifice plate.

[0017] The diameters of the holes in the primary, secondary, and tertiary orifice plates are 41.2 mm, 60 mm, and 74.8 mm, respectively.

[0018] The significant advantages of this invention are:

[0019] (1) The multi-stage orifice plate for draining the main steam header of a nuclear power plant is provided with installation grooves at the first-stage orifice plate and the third-stage orifice plate respectively, and arc transitions are provided on the front and rear sides of the first-stage and third-stage orifice plates, so that the opening of the installation grooves will not affect the strength of the orifice plate.

[0020] (2) The anti-slip ring and the middle strip of the strip structure of the device of the present invention can play an anti-slip role during the handling and installation of the device, thereby making the installation of the device more convenient; in addition, the middle strip can also enhance the overall strength of the cylindrical body to a certain extent.

[0021] (3) The device of the present invention has a simple overall structure, is easy to use, and has high stability and practicality. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the multi-stage perforated plate of the present invention. Figure 1 ;

[0023] Figure 2 This is a schematic cross-sectional view of the multi-stage perforated plate of the present invention;

[0024] Figure 3 This is a schematic diagram of the multi-stage perforated plate of the present invention. Figure 2 ;

[0025] In the diagram: 1. Cylindrical main body; 2. Primary perforated plate; 3. Secondary perforated plate; 4. Tertiary perforated plate; 5. Arc transition; 6. Mounting groove; 601. Anti-slip ring; 7. Central strip. Detailed Implementation

[0026] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0027] like Figure 1 , 2The diagram illustrates a multi-stage orifice plate for draining the main steam header of a nuclear power plant. It includes a cylindrical body 1, with a primary orifice plate 2, a secondary orifice plate 3, and a tertiary orifice plate 4 arranged from front to back along the inner side of the cylindrical body 1. The primary, secondary, and tertiary orifice plates 2, 3, and 4 are all circular flat plates with through holes machined in the center, and they are parallel to each other. The diameters of the holes in the primary, secondary, and tertiary orifice plates 2, 3, and 4 are 41.2 mm, 60 mm, and 74.8 mm, respectively.

[0028] Arc transitions 5 are machined on the front and rear sides of the first-stage perforated plate 2, the second-stage perforated plate 3, and the third-stage perforated plate 4, at the junctions with the inner wall of the cylindrical body 1.

[0029] On the outer wall of the cylindrical body 1, at positions corresponding to the primary perforated plate 2 and the tertiary perforated plate 4, annular mounting grooves 6 are respectively machined. Anti-slip rings 601 are installed inside the mounting grooves 6, and the dimensions of the anti-slip rings 601 are adapted to the dimensions of the mounting grooves 6. Figure 3 As shown, a central strip 7 is machined on the outer wall of the cylindrical body 1, between the two mounting grooves 6. There are four central strips 7 in total, arranged axially along the cylindrical body 1 and distributed circumferentially on the outer wall of the cylindrical body 1.

[0030] The front and rear edges of the cylindrical body 1 are both machined with 45° chamfers to ensure smooth edges.

[0031] The cylindrical main body 1, the primary perforated plate 2, the secondary perforated plate 3, the tertiary perforated plate 4, and the central strip 7 are integrally formed.

[0032] The mounting slots 6 are located at the primary perforated plate 2 and the tertiary perforated plate 4, respectively. Furthermore, the front and rear sides of both the primary and tertiary perforated plates 2 and 4 are provided with arc transitions 5, ensuring that the mounting slots 6 do not affect the strength of the perforated plates. The anti-slip rings 601 and the strip-shaped central strip 7 provide anti-slip properties during the handling and installation of this device, making installation more convenient. Additionally, the central strip 7 also enhances the overall strength of the cylindrical body 1 to a certain extent.

[0033] When using the multi-stage orifice plate for draining the main steam header of a nuclear power plant according to the present invention, the device can be used normally by simply installing it in the corresponding position on the nuclear power plant equipment.

[0034] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A multi-stage orifice plate for draining the main steam header of a nuclear power plant, characterized in that: It includes a cylindrical body (1), and a multi-stage perforated plate is provided on the inner side of the cylindrical body (1) from front to back; The multi-stage perforated plates are all circular flat plates with through holes machined in the middle, and they are arranged in parallel to each other; On the outer wall of the cylindrical body (1), at positions corresponding to the first-stage perforated plate and the last-stage perforated plate, mounting grooves (6) are respectively machined, and anti-slip rings (601) are installed inside the mounting grooves (6). A central strip (7) is machined on the outer wall of the cylindrical body (1) between the two mounting slots (6); The central strip (7) is arranged along the axial direction of the cylindrical body (1) and is circumferentially distributed on the outer wall of the cylindrical body (1); Arc transitions (5) are machined on the front and rear sides of the first-stage perforated plate and the last-stage perforated plate, at the junction with the inner wall of the cylindrical body (1).

2. The multi-stage orifice plate for draining the main steam header of a nuclear power plant as described in claim 1, characterized in that: The cylindrical body (1) is integrally formed with the multi-stage perforated plate and the middle strip (7).

3. The multi-stage orifice plate for draining the main steam header of a nuclear power plant as described in claim 1, characterized in that: At the front and rear sides of each perforated plate and at the junction with the inner wall of the cylindrical body (1), arc transitions (5) are respectively processed.

4. A multi-stage orifice plate for draining the main steam header of a nuclear power plant as described in claim 1, characterized in that: The front and rear edges of the cylindrical body (1) are both machined with 45° chamfers.

5. A multi-stage orifice plate for draining the main steam header of a nuclear power plant as described in claim 1, characterized in that: The multi-stage perforated plate has holes whose diameters gradually increase from front to back.

6. A multi-stage orifice plate for draining the main steam header of a nuclear power plant as described in claim 1, characterized in that: The multi-stage perforated plate includes a primary perforated plate (2), a secondary perforated plate (3), and a tertiary perforated plate (4).

7. A multi-stage orifice plate for draining the main steam header of a nuclear power plant as described in claim 6, characterized in that: The diameters of the holes on the first-stage perforated plate (2), the second-stage perforated plate (3), and the third-stage perforated plate (4) are 41.2 mm, 60 mm, and 74.8 mm, respectively.

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