Bolt binding type disc seal

Abstract

The utility model discloses a bolt binding type disc seal, which comprises a sealing piece arranged at the top of a sealing boss and a valve disc of a volute disc valve arranged above the sealing piece, the sealing piece comprises an annular rubber seal, a steel ring is concentrically and coaxially embedded at the top of the rubber seal, and the steel ring is fixedly matched with the rubber seal. An installation opening is formed in the middle of the rubber seal, a valve disc of the volute disc valve is concentrically and coaxially embedded in the installation opening, the outer edge of the valve disc is connected to the steel ring in a bearing mode, and the outer edge of the valve disc is detachably and fixedly matched with the steel ring through a plurality of bolts. According to the bolt binding type disc sealing structure, the problem that a sealing piece is damaged by high temperature caused by a traditional welding method is solved, adverse factors such as disc stress deformation caused by asymmetry of welding positions are also eliminated, and therefore the overall quality of equipment installation is improved. When the sealing element needs to be maintained or replaced, only the bolt needs to be detached.

Description

Technical Field

[0001] The utility model relates to the technical field of maintenance of hydrogenerator units, in particular to a bolted disc seal. Background Art

[0002] The spiral case disc valve of a hydrogenerator unit is a specific device for draining water in the spiral case and part of the penstock during unit maintenance. During unit operation, the disc valve is in a closed state. If the disc seal of the disc valve is not tight or falls off, the water in the penstock will directly flow into the draft tube, causing hydraulic losses. Long-term leakage may also lead to increased vibration and cavitation of the spiral case connected to the draft tube, and cracks may occur in the pipeline, causing pipeline leakage, posing a risk of flooding the powerhouse and threatening the safe and stable operation of the power station.

[0003] Initially, the seal of the spiral case disc valve of a certain hydrogenerator unit used a special-shaped rubber sealing strip, which was installed on the valve disc through a number of seal positioning pins. As Figure 1 shown, when the disc valve is closed, the sealing strip on the valve disc is in close contact with the valve seat sealing surface. When the disc valve is opened for drainage during unit maintenance, the disc valve opens upward. When the valve disc disengages from the valve seat, a large adsorption force is generated between the sealing strip and the valve seat. In addition, the flow velocity and pressure of the water flowing through the sealing surface are relatively high. The large adsorption force and high-flow velocity water pressure make the rubber sealing strip easy to be broken and fall off.

[0004] For the above reasons, after the disc valve is repeatedly opened and closed multiple times, the sealing strip on the valve disc will surely be torn at the processed round holes, causing the rubber sealing strip to fall off from the sealing groove, affecting the sealing effect of the disc valve and causing the disc valve to leak.

[0005] Currently, after a structural improvement once, the structure is as Figure 2 shown. The existing rubber seal is changed to a form combining metal and rubber. The metal and rubber adopt a vulcanization process to firmly bond the metal and the sealing material together. The metal becomes the support skeleton of the sealing material, which can solve the problem of the seal being cut off. The new seal is connected to the valve disc by spot welding. Before installing the seal, the Figure 1 sealing support boss in is polished, the seal is installed into the groove, the upper surface of the seal is made to be in close contact with the groove, and then the seal is fixed. The metal part at the bottom of the seal is fixed to the groove by welding to prevent it from falling off.

[0006] However, it still has the following disadvantages:

[0007] When the metal part of the seal is welded to the groove section by section, first, the space on the valve disc is limited, increasing the welding difficulty and affecting the welding quality. Second, the welding temperature is not easy to control, resulting in a relatively high temperature and damaging the rubber seal. Third, when the seal is replaced, grinding and welding are required, and the construction period is relatively long. Content of the Utility Model

[0008] The utility model provides a bolted disc seal, aiming to solve the problems that in the prior art, the rubber sealing strip is easily broken and falls off, the welding quality is poor, and the welding high temperature affects the sealing quality.

[0009] To solve the above technical problems, the technical solution adopted by the utility model is as follows:

[0010] A bolted disc seal includes a sealing member provided at the top of a sealing boss and a valve disc of a volute disc valve provided above the sealing member. The sealing member includes an annular rubber seal. A steel ring is concentrically and coaxially embedded at the top of the rubber seal, and the steel ring is fixedly matched with the rubber seal. An installation opening is formed in the middle of the rubber seal. The valve disc of the volute disc valve is concentrically and coaxially embedded in the installation opening, and the outer edge of the valve disc abuts on the steel ring. The outer edge of the valve disc forms a detachable fixed fit with the steel ring through a plurality of bolts.

[0011] Preferably, the top of the steel ring is flush with the top of the rubber seal. The bottom of the outer edge of the valve disc abuts on the tops of both the steel ring and the rubber seal at the same time and forms a sealing fit with the sealing member composed of the steel ring and the rubber seal.

[0012] More preferably, a plurality of fixing screw holes are provided on the steel ring at equal intervals around the axis, and a plurality of positioning holes are provided on the outer edge of the valve disc at equal intervals around the axis. The number of the fixing screw holes is the same as that of the positioning holes and they correspond to each other one by one.

[0013] Furthermore, the corresponding fixing screw holes and positioning holes are concentrically and coaxially communicated. After the bolt passes through the positioning hole, it forms a threaded fit with the corresponding fixing screw hole.

[0014] Even further, a sealing washer is clamped between the nut end of the bolt and the top of the valve disc, and the bolt forms a sealing fit with the positioning hole through the sealing washer.

[0015] Specifically, a thread locking adhesive is applied to the threaded fit part of the bolt and the fixing screw hole.

[0016] More specifically, there are at least 12 bolts.

[0017] The beneficial effects of the utility model are as follows:

[0018] (1) Solve the problem that the rubber sealing strip is easily broken and falls off;

[0019] (2) Solve the problems of poor welding quality of the rubber seal and the welding high temperature affecting the sealing quality;

[0020] (3) Through structural optimization, the utility model can ensure the sealing effect and is more convenient for seal replacement and maintenance. Description of the Drawings

[0021] Figure 1Schematic installation cross-section diagram of the first prior art of the present utility model;

[0022] Figure 2 Schematic installation cross-section diagram of the second prior art of the present utility model;

[0023] Figure 3 Schematic installation cross-section diagram of the present utility model;

[0024] In the figure: 1, valve disc; 2, steel ring; 3, rubber seal; 4, bolt; 5, sealing washer; 6, positioning hole; 7, fixing screw hole; 8, installation port. Specific implementation mode

[0025] As follows, the embodiments will be further described with reference to the accompanying drawings.

[0026] As Figure 3 shown, as a preferred Embodiment 1, a bolt-fastened disc seal includes a seal member provided at the top of a sealing boss and a valve disc 1 of a volute disc valve provided above the seal member. The seal member includes an annular rubber seal 3. A steel ring 2 is concentrically and coaxially embedded at the top of the rubber seal 3, and the steel ring 2 is fixedly engaged with the rubber seal 3. An installation port 8 is formed in the middle of the rubber seal 3. The valve disc 1 of the volute disc valve is concentrically and coaxially embedded in the installation port 8, and the outer edge of the valve disc 1 abuts on the steel ring 2. The outer edge of the valve disc 1 is detachably fixedly engaged with the steel ring 2 through a plurality of bolts 4.

[0027] The top of the steel ring 2 is flush with the top of the rubber seal 3. The steel ring 2 and the rubber seal 3 are bonded together firmly by vulcanization process for the metal material and the sealing material. According to the material "Indirect Evidence of Molecular Orientation Behavior during Metal-Rubber Vulcanization Bonding", the bonding force > 10 Mpa by this method is sufficient to ensure that during the drainage of the unit, the water pressure will not wash away the rubber part, forming a seal member with the steel ring 2. The bottom of the outer edge of the valve disc 1 abuts on the tops of both the steel ring 2 and the rubber seal 3 at the same time and forms a sealing fit with the seal member composed of the steel ring 2 and the rubber seal 3.

[0028] A plurality of fixing screw holes 7 are provided on the steel ring 2 at equal intervals around the axis. A plurality of positioning holes 6 are provided on the outer edge of the valve disc 1 at equal intervals around the axis. The number of the fixing screw holes 7 is the same as that of the positioning holes 6 and they correspond to each other one by one.

[0029] The corresponding fixing screw holes 7 and positioning holes 6 are concentrically and coaxially communicated. The bolt 4 passes through the positioning hole 6 and forms a threaded fit with the corresponding fixing screw hole 7.

[0030] A sealing washer 5 is clamped between the fixed nut end of the bolt 4 and the top of the valve disc 1, and the bolt 4 and the positioning hole 6 form a sealing fit through the sealing washer 5.

[0031] Embodiment 1 provides a bolt-fastened disc seal. A seal member with a steel ring 2 is formed by the steel ring 2 and the sealing rubber 3. During installation, the valve disc 1 is embedded in the installation opening 8 of the seal member, and the valve disc 1 is placed on the seal member. Then, the positioning holes 6 and the fixing screw holes 7 are aligned one by one, and the corresponding bolts 4 pass through the positioning holes 6 and are threadedly engaged with the fixing screw holes 7, so that the valve disc 1 and the steel ring 2 of the seal member form a detachable fixed fit. The sealing between the bolt 4 and the positioning hole 6 is achieved through the sealing washer 5, ensuring the connection strength and the sealing effect. The problem that the rubber sealing strip is easily broken and detached is avoided by the steel ring 2. Secondly, the problems of poor welding quality of the rubber seal 3 and the influence of the welding high temperature on the sealing quality caused by welding are avoided through the mechanical fixing method, which is convenient for installation and disassembly.

[0032] As a preferred Embodiment 2, the sizes of the fixing screw holes 7 are all the same, and the positioning holes 6 are threaded holes matching the fixing screw holes 7. During installation, the connection strength after installation can be further ensured by the bolts 2.

[0033] As a preferred Embodiment 3, a thread locking adhesive is applied to the threaded engagement part of the bolt 4 and the fixing screw hole 7. Further ensure the connection strength after installation.

[0034] As a preferred Embodiment 4, there are at least 12 bolts 4. Ensure the connection strength and the evenness of the force.

[0035] The working principle of the present utility model:

[0036] The present utility model provides a bolt-fastened disc seal. A seal member with a steel ring 2 is formed by the steel ring 2 and the sealing rubber 3. During installation, the valve disc 1 is embedded in the installation opening 8 of the seal member, and the valve disc 1 is placed on the seal member. Then, the positioning holes 6 and the fixing screw holes 7 are aligned one by one, and the corresponding bolts 4 pass through the positioning holes 6 and are threadedly engaged with the fixing screw holes 7, so that the valve disc 1 and the steel ring 2 of the seal member form a detachable fixed fit. The sealing between the bolt 4 and the positioning hole 6 is achieved through the sealing washer 5, ensuring the connection strength and the sealing effect. The problem that the rubber sealing strip is easily broken and detached is avoided by the steel ring 2. Secondly, the problems of poor welding quality of the rubber seal 3 and the influence of the welding high temperature on the sealing quality caused by welding are avoided through the mechanical fixing method, which is convenient for installation and disassembly.

Claims

1. A bolt-on disc seal, comprising a seal member disposed on the top of a sealing boss and a valve disc (1) of a volute disc valve disposed above the seal member, characterized in that: The sealing member comprises an annular rubber seal (3), a steel ring (2) is coaxially and concentrically embedded on the top of the rubber seal (3), and the steel ring (2) and the rubber seal (3) are fixedly matched, a mounting opening (8) is formed in the middle of the rubber seal (3), a valve disc (1) of the volute disc valve is coaxially and concentrically embedded in the mounting opening (8), and the outer edge of the valve disc (1) is supported on the steel ring (2), and the outer edge of the valve disc (1) is detachably fixedly matched with the steel ring (2) via a plurality of bolts (4).

2. A bolt-on disc seal according to claim 1, characterized in that: The top of the steel ring (2) is flush with the top of the rubber seal (3), and the bottom of the outer edge of the valve disc (1) is supported on the top of the steel ring (2) and the rubber seal (3) at the same time, and forms a sealing fit with the sealing member formed by the steel ring (2) and the rubber seal (3).

3. A bolt-on disc seal according to claim 2, characterized in that: The steel ring (2) is provided with a plurality of fixing screw holes (7) at equal intervals around the axis, and the outer edge of the valve disc (1) is provided with a plurality of positioning holes (6) at equal intervals around the axis. The number of the fixing screw holes (7) and the positioning holes (6) are the same and correspond one to one.

4. A bolt-on disc seal according to claim 3, characterized in that: The corresponding fixing screw hole (7) is coaxially connected to the positioning hole (6), and the bolt (4) passes through the positioning hole (6) to form a threaded fit with the corresponding fixing screw hole (7).

5. A bolt-on disc seal according to claim 4, characterized in that: A sealing gasket (5) is clamped between the fixing nut end of the bolt (4) and the top of the valve disc (1), and the bolt (4) and the positioning hole (6) form a sealing fit through the sealing gasket (5).

6. A bolt-on disc seal according to claim 5, characterized in that: The thread-matching portion between the bolt (4) and the fixing screw hole (7) is coated with thread-locking glue.

7. A bolt-on disc seal according to claim 6, characterized in that: There are at least 12 bolts (4).

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