Grinding tool for high-pressure steam valve of steam turbine
By combining a grinding rod, a grinding valve core, and a permanent magnet chuck, the problem of inaccurate positioning of grinding tools for high-pressure valves in steam turbines has been solved, achieving efficient and precise valve grinding and improving sealing performance and maintenance efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHANXI SOGO POWER GENERATION CO LTD
- Filing Date
- 2025-06-11
- Publication Date
- 2026-05-12
AI Technical Summary
Existing grinding tools for high-pressure steam turbine valves cannot accurately determine the grinding depth, resulting in over- or under-grinding, which affects the valve's sealing performance. Furthermore, traditional manual grinding is inefficient and makes it difficult to guarantee quality.
It adopts a combined structure including a grinding rod, a grinding valve core, a positioning device and a permanent magnet chuck. The valve seat is fixed by the permanent magnet chuck, and the grinding parameters are adjusted in real time by the positioning device and the observation hole to ensure accurate positioning and efficient grinding.
It achieves efficient and precise valve grinding, improves grinding quality and efficiency, ensures valve sealing performance, and reduces the labor intensity of maintenance personnel.
Smart Images
Figure CN224223573U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of valve grinding technology, and in particular to grinding tools for high-pressure steam valves of steam turbines. Background Technology
[0002] High-pressure valves in steam turbines are located on the main steam pipeline and are subjected to high-temperature, high-pressure steam during operation. Under high-temperature conditions, the oxidation rate of metals can suddenly accelerate within a certain temperature range. For iron-based alloys, an oxide layer will form when the temperature rises to a certain point. When the oxide layer reaches a certain thickness, it will peel off when operating conditions change. When the oxide scale is squeezed by the valve core and valve seat, the sealing surface is damaged, causing internal leakage in the valve. Internal leakage in the main steam valve increases energy consumption, causing steam to enter the turbine without being effectively utilized. Severe internal leakage prolongs the rotor coasting time, leading to abnormally high speed and affecting the stable operation of the unit. Long-term leakage causes grooves to be eroded on internal components, seriously affecting the safe and economical operation of the unit.
[0003] Existing valve grinding tools cannot accurately determine the grinding depth during grinding, and rely solely on the experience of maintenance personnel to grind the valve seat, which easily leads to over-grinding or insufficient grinding. In the grinding process, traditional manual grinding is inefficient and the grinding quality is not easy to guarantee. In order to reduce the labor intensity of maintenance personnel and improve maintenance efficiency and grinding accuracy, a flexible and versatile steam turbine high-pressure valve repair and grinding tool has been invented. Utility Model Content
[0004] To solve the above-mentioned technical problems, this utility model provides a grinding tool for high-pressure steam valves of steam turbines.
[0005] This utility model is achieved using the following technical solution: a grinding tool for high-pressure steam valves of a steam turbine, including a grinding rod, a grinding valve core slidably connected to the surface of the grinding rod, a fixing groove at the bottom of the surface of the grinding rod, an insertion groove at the top of the grinding valve core, a connecting groove at the top of the surface of the grinding valve core, a fixing device inside the grinding rod, a positioning device on the surface of the grinding rod, and a connector fixedly connected to the top of the grinding rod.
[0006] Through the above technical solution, the positioning plate is also a permanent magnet chuck. When the permanent magnet chuck is aligned with the top of the valve seat by the grinding rod and the handle is rotated to the left, the permanent magnet inside is aligned with the guide disk. The magnetic field radiates outward through the guide disk and penetrates to the surface of the valve seat, forming a closed magnetic circuit. This magnetizes the metal of the valve seat, causing it to attract the chuck and thus achieve a stable fixation. After grinding is completed, the chuck handle is rotated to the right, and the permanent magnet is aligned with the non-magnetic isolation layer. The magnetic lines of force form a self-closed loop inside the chuck, and the magnetic field on the surface of the guide disk almost disappears. The attraction force is then released, and the chuck can be easily removed.
[0007] The connector is fixed to the top of the grinding rod and is used to thread a variable speed pistol spinner to transmit the power of the spinner to the grinding rod, which in turn drives the grinding valve core to perform the grinding work. It is a key component for power transmission.
[0008] As a further improvement to the above solution, the surface of the grinding rod is slidably connected to the inner wall of the fixing groove, the fixing groove is connected to the connecting groove, and the connecting groove is connected to the insertion groove.
[0009] Through the above technical solution, the connecting groove is located on the top of the grinding valve core surface and communicates with the fixing groove. Together with the bolts and nuts, they form a fixing structure, so that the grinding rod and the grinding valve core are firmly connected, ensuring the stability of the grinding operation.
[0010] As a further improvement to the above solution, the fixing device includes a bolt, the surface of which is threaded with a nut.
[0011] As a further improvement to the above solution, the bolt is located inside the grinding valve core, the surface of the bolt is slidably connected to the inner wall of the fixing groove, and the surface of the bolt is slidably connected to the inner wall of the connecting groove.
[0012] As a further improvement to the above solution, the positioning device includes a positioning disk, an observation hole and a positioning hole on the top of the positioning disk, a positioning ring fixedly connected to the bottom of the positioning disk, threads on the surface of the positioning ring, and a brake retaining ring threadedly connected to the surface of the positioning ring.
[0013] With the above technical solution, two observation holes are opened on the top of the positioning plate and are symmetrically distributed in a central manner. Operators can observe the grinding process in real time through the observation holes, understand the grinding status in a timely manner, and adjust the grinding parameters to ensure the grinding quality.
[0014] As a further improvement to the above solution, the positioning plate is located on the surface of the grinding rod, the inner wall of the positioning hole is slidably connected to the grinding rod, and there are two observation holes, which are symmetrically and evenly distributed around the top center of the positioning plate, with the positioning hole located in the middle of the observation holes.
[0015] As a further improvement to the above solution, a through groove is provided at the bottom of the positioning ring, and the through groove at the bottom of the positioning ring communicates with the positioning hole. The number of brake rings is set to several.
[0016] Through the above technical solution, the brake retaining ring can be adjusted to fix the position of the positioning disc, further ensuring that the grinding rod is ground at the center of the valve seat sealing ring, thus guaranteeing the grinding accuracy.
[0017] Compared with the prior art, the beneficial effects of this utility model are as follows:
[0018] This invention features a positioning disc. When the positioning disc needs to be replaced, it is removed from the grinding rod through the positioning hole on the top of the disc. A suitable positioning disc is then selected based on the inner diameter of the high-pressure valve cover stop. By replacing the positioning disc, valves of different sizes can be ground, simplifying tool fixation. The positioning disc is a permanent magnet chuck. When the permanent magnet chuck is aligned with the top of the valve seat through the grinding rod and the handle on the surface of the permanent magnet chuck is rotated to the left, its internal permanent magnet aligns with the guide disk. The magnetic field radiates outward through the guide disk and penetrates to the surface of the valve seat, forming a closed magnetic circuit. This magnetizes the valve seat metal, causing it to attract the chuck and achieve a stable fixation. After grinding, the handle of the chuck is rotated to the right, aligning the permanent magnet with the non-magnetic isolation layer. The magnetic lines of force form a self-closed loop inside the chuck, and the magnetic field on the surface of the guide disk almost disappears, releasing the attraction force and allowing the chuck to be easily removed. Attached Figure Description
[0019] Figure 1 This is a schematic diagram of the overall structure of this utility model;
[0020] Figure 2 This is a schematic diagram of the grinding valve core structure of this utility model;
[0021] Figure 3 This is a schematic diagram of the positioning disc structure of this utility model;
[0022] Figure 4 This is a schematic diagram of the brake retaining ring structure of this utility model.
[0023] Explanation of key symbols:
[0024] 1. Grinding rod; 2. Grinding valve core; 3. Fixing groove; 4. Insertion groove; 5. Connecting groove; 6. Fixing device; 61. Bolt; 62. Nut; 7. Positioning device; 71. Positioning plate; 72. Observation hole; 73. Positioning hole; 74. Positioning ring; 75. Thread; 76. Brake circlip; 8. Connector. Detailed Implementation
[0025] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.
[0026] Example:
[0027] Please combine Figure 1-4The turbine high-pressure steam valve grinding tool of this embodiment includes a grinding rod 1, a grinding valve core 2 slidably connected to the surface of the grinding rod 1, a fixing groove 3 opened at the bottom of the surface of the grinding rod 1, an insertion groove 4 opened at the top of the grinding valve core 2, a connecting groove 5 opened at the top of the surface of the grinding valve core 2, a fixing device 6 provided inside the grinding rod 1, a positioning device 7 provided on the surface of the grinding rod 1, and a connector 8 fixedly connected to the top of the grinding rod 1.
[0028] The surface of the grinding rod 1 is slidably connected to the inner wall of the fixing groove 3. The fixing groove 3 is connected to the connecting groove 5, and the connecting groove 5 is connected to the insertion groove 4.
[0029] The fixing device 6 includes a bolt 61 with a nut 62 threaded onto its surface. The bolt 601 passes through the fixing groove 3 at the bottom of the grinding rod 1 and the connecting groove 5 at the top of the grinding valve core 2. The nut 602 is then tightened to fix the bolt, thereby achieving a stable connection between the grinding rod 1 and the grinding valve core 2.
[0030] Bolt 61 is located inside the grinding valve core 2. The surface of bolt 61 is slidably connected to the inner wall of the fixing groove 3 and the surface of bolt 61 is slidably connected to the inner wall of the connecting groove 5.
[0031] The positioning device 7 includes a positioning disc 71. The top of the positioning disc 71 has an observation hole 72 and a positioning hole 73. A positioning ring 74 is fixedly connected to the bottom of the positioning disc 71. The surface of the positioning ring 74 has threads 75, and a brake retaining ring 76 is threaded onto the surface of the positioning ring 74. A suitable positioning disc 701 is selected based on the inner diameter of the high-pressure valve cover stop, so that the positioning hole 73 on the top of the positioning disc 701 fits onto the grinding rod 1. Then, it is attracted to the valve seat by a permanent magnet chuck, or connected to the valve seat by the threads on the surface of the positioning ring 74. The brake retaining ring 76 on the positioning ring 74 is adjusted to fix the position of the positioning disc 701. During this process, the operation can be observed through the observation hole 702. Finally, a variable-speed pistol is threaded onto the top of the valve stem to control the grinding speed, ensuring that the valve stem remains at the center of the valve seat sealing ring during the grinding process, effectively grinding the valve and ensuring its sealing performance.
[0032] The positioning disc 71 is located on the surface of the grinding rod 1. The inner wall of the positioning hole 73 is slidably connected to the grinding rod 1. There are two observation holes 72, which are symmetrically and evenly distributed around the top center of the positioning disc 71. The positioning hole 73 is located in the middle of the observation holes 72. The positioning disc 71 has several sizes. When the positioning disc 71 needs to be replaced, first make the magnet of the positioning disc 71 disappear. Then, through the thread on the surface of the positioning ring 74 at the bottom of the positioning disc 71, it is threaded upward from the inner wall of the valve and then taken out from the grinding rod 1 through the positioning hole 73 at the top of the positioning disc 71. Then, select the appropriate positioning disc 71 according to the inner diameter of the high-pressure valve cover stop.
[0033] The bottom of the positioning ring 74 is provided with a through groove, which communicates with the positioning hole 73. The number of brake rings 76 is set to several.
[0034] The implementation principle of the turbine high-pressure steam valve grinding tool in this embodiment is as follows: First, the grinding rod 1 is passed through the insertion groove 4 at the top of the grinding valve core 2. Then, the bolt 601 is passed through the fixing groove 3 at the bottom of the grinding rod 1 and the connecting groove 5 at the top of the grinding valve core 2, and then tightened with the nut 602 to achieve a stable connection between the grinding rod 1 and the grinding valve core 2. Next, according to the inner diameter of the high-pressure valve cover stop, a suitable positioning plate 701 is selected so that the positioning hole 73 at the top of the positioning plate 701 is fitted onto the grinding rod 1. Then, the grinding valve core 2 is placed inside the high-pressure valve and is attracted to the top of the valve seat by a permanent magnet chuck, or connected to the inner wall of the valve seat by the threaded hole on the surface of the positioning ring 74. The brake ring 76 on the positioning ring 74 is adjusted to fix the position of the positioning plate 701. During this process, the operation can be observed through the observation hole 702. Finally, a variable speed pistol is connected to the threaded joint at the top of the valve stem to control the grinding speed, ensuring that the valve stem is always in the center of the valve seat sealing ring during the grinding process, effectively grinding the valve and ensuring the valve's sealing performance.
[0035] The above embodiments are merely preferred embodiments of this utility model and should not be construed as limiting the scope of protection of this utility model. Any non-substantial changes and substitutions made by those skilled in the art based on this utility model shall fall within the scope of protection claimed by this utility model.
Claims
1. A grinding tool for high-pressure steam valves of a steam turbine, characterized in that, The device includes a grinding rod (1), a grinding valve core (2) which is slidably connected to the surface of the grinding rod (1), a fixing groove (3) which is opened at the bottom of the surface of the grinding rod (1), a plug-in groove (4) which is opened at the top of the grinding valve core (2), a connecting groove (5) which is opened at the top of the surface of the grinding valve core (2), a fixing device (6) which is provided inside the grinding rod (1), a positioning device (7) which is provided on the surface of the grinding rod (1), and a connector (8) which is fixedly connected to the top of the grinding rod (1).
2. The turbine high-pressure steam valve grinding tool as described in claim 1, characterized in that: The surface of the grinding rod (1) is slidably connected to the inner wall of the fixing groove (3), the fixing groove (3) is connected to the connecting groove (5), and the connecting groove (5) is connected to the insertion groove (4).
3. The turbine high-pressure steam valve grinding tool as described in claim 1, characterized in that: The fixing device (6) includes a bolt (61) with a nut (62) threaded onto its surface.
4. The turbine high-pressure steam valve grinding tool as described in claim 3, characterized in that: The bolt (61) is located inside the grinding valve core (2), the surface of the bolt (61) is slidably connected to the inner wall of the fixing groove (3), and the surface of the bolt (61) is slidably connected to the inner wall of the connecting groove (5).
5. The turbine high-pressure steam valve grinding tool as described in claim 1, characterized in that: The positioning device (7) includes a positioning disk (71), an observation hole (72) is provided on the top of the positioning disk (71), a positioning hole (73) is provided on the top of the positioning disk (71), a positioning ring (74) is fixedly connected to the bottom of the positioning disk (71), a thread (75) is provided on the surface of the positioning ring (74), and a brake ring (76) is threadedly connected to the surface of the positioning ring (74).
6. The turbine high-pressure steam valve grinding tool as described in claim 5, characterized in that: The positioning disk (71) is located on the surface of the grinding rod (1), the inner wall of the positioning hole (73) is slidably connected to the grinding rod (1), and there are two observation holes (72). The two observation holes (72) are symmetrically and evenly distributed around the top center of the positioning disk (71), and the positioning hole (73) is located in the middle of the observation holes (72).
7. The turbine high-pressure steam valve grinding tool as described in claim 5, characterized in that: The bottom of the positioning ring (74) is provided with a through groove, and the through groove at the bottom of the positioning ring (74) is connected to the positioning hole (73). The number of brake rings (76) is set to several.