Steam turbine control valve

Abstract

The invention belongs to the technical field of steam turbines, and particularly relates to a steam turbine control valve which comprises a valve shell with an opening in the upper end, a valve cover covering the opening in the upper end of the valve shell, a valve core arranged in the valve shell, and a valve core arranged in the valve shell and provided with an air inlet and an air outlet, the lower end of the valve deck extends downwards into the valve shell cavity to form a valve seat, a valve seat cavity with an opening in the lower end is formed in the middle of the valve seat, and a plurality of arc-shaped rods are arranged on the side wall of the valve seat cavity. And the valve core is in sliding fit with the valve seat cavity. According to the technical scheme, when the steam turbine control valve and the valve rod drive the valve element to move in the up-down direction, the arc-shaped rod is in sliding fit with the first groove body in the up-down direction, the limiting column is in sliding fit with the second groove body in the up-down direction, the constraint conditions of the valve rod and the valve element are changed, and the situation that in the operation process of the control valve, the valve rod and the valve element rotate is avoided; the structure and the anti-vibration capability are improved; meanwhile, relative rotation of the valve rod and the valve element is prevented, and assembly looseness of the valve rod and the valve element is avoided.

Description

Technical Field

[0001] The invention belongs to the technical field of steam turbines, and particularly relates to a steam turbine governing valve. Background Art

[0002] A steam turbine, also known as a steam turbine engine, is a rotary steam power device. High-temperature and high-pressure steam passes through a fixed nozzle to become an accelerated air flow and then jets onto the blades, causing the rotor equipped with the blade row to rotate and do work externally at the same time. A steam turbine is the main equipment of a modern thermal power plant and is also used in the metallurgical industry, chemical industry, and ship power plants.

[0003] A steam turbine governing valve, also known as a regulating steam valve, adjusts the steam flow rate entering the steam turbine, thereby adjusting the rotational speed and output power of the steam turbine, and has the functions of maintaining the stable operation of the unit and protecting the safety of the steam turbine. In a steam turbine governing valve, an oil motor is usually used as an actuator, and the valve stem drives the valve core to move up and down to control the distance between the valve core and the air outlet to complete the opening or closing of the governing valve.

[0004] During the operation of the governing valve, the valve stem may rotate. Also, since the valve stem and the valve core are generally assembled by threads, there is a situation where the rotation of the valve stem causes the valve stem and the valve core to become loose.

[0005] In view of the above problems, a steam turbine governing valve is designed. Summary of the Invention

[0006] The invention proposes the following technical solutions for the problems in the prior art:

[0007] A steam turbine governing valve, comprising:

[0008] A valve housing with an upper end opening, the valve housing having an air inlet and an air outlet, and a valve housing cavity is formed at the position where the air inlet and the air outlet extend and intersect.

[0009] A valve cover covering the upper end opening of the valve housing, the lower end of the valve cover extending downward into the valve housing cavity to form a valve seat. A valve seat cavity with a lower end opening is formed in the middle of the valve seat. A plurality of arc-shaped rods are arranged on the side wall of the valve seat cavity, and a limiting column is arranged on the valve cover.

[0010] A valve core slidably matched with the valve seat cavity, a valve stem is threadedly assembled at the upper end of the valve core, the valve stem extends upward through the valve cover and is slidably and sealingly matched with the valve cover. A first groove is arranged on the valve core along the axial direction of the valve stem, and the number of the first grooves matches the number of the arc-shaped rods. A disc is sleeved on a section of the valve stem outside the valve cover, and a second groove is formed on the disc.

[0011] One end of the valve stem located outside the valve cover is connected to the piston shaft of an external oil motor through a coupling. The valve stem drives the valve core to move in the axial direction of the valve stem. At this time, the arc-shaped rod is located inside the first groove body and is slidably matched with it. The limiting post penetrates through the second groove body in the axial direction. When the valve core moves to the lowest position, it is hermetically matched with the air outlet.

[0012] As a preference of the above technical solution, an installation groove with an open upper end and a limiting through hole communicating the installation groove with the valve seat cavity are provided on the valve cover. The limiting post is hermetically matched in the installation groove. An installation groove two with an open upper end and an arc-shaped through hole communicating the installation groove two with the outside of the side wall of the limiting post are provided on the limiting post. An arc-shaped rod is slidably matched in the arc-shaped through hole. The arc-shaped through hole and the arc-shaped rod are concentrically arranged;

[0013] A long rod is assembled in the installation groove two. When the long rod is inserted into the installation groove two, one end of the arc-shaped rod located inside the installation groove two is squeezed, until one end of the arc-shaped rod located outside the installation groove two penetrates through the arc-shaped through hole and abuts against the side wall of the valve seat cavity.

[0014] As a preference of the above technical solution, an installation through hole communicating the installation groove two with the outside of the bottom wall of the limiting post is provided on the limiting post. A threaded hole is provided at the bottom of the installation groove. A screw rod is connected to the lower end of the long rod. The screw rod penetrates through the installation through hole and is threadedly matched with the threaded hole.

[0015] As a preference of the above technical solution, a magnet is connected to the end of the screw rod. An armature is provided at the end of the arc-shaped rod located inside the installation groove two;

[0016] When the long rod is taken out from the limiting post, the magnet adsorbs the arc-shaped rod to drive the arc-shaped rod to rotate in the arc-shaped through hole, until one end of the arc-shaped rod located outside the installation groove two enters the inside of the arc-shaped through hole.

[0017] As a preference of the above technical solution, anti-rotation ribs are provided on the outer side wall of the limiting post. The installation groove and the outer shell are matched.

[0018] As a preference of the above technical solution, a filter screen is provided between the valve shell and the valve cover. Both the valve seat and the valve core are located inside the filter screen.

[0019] The beneficial effects of the present invention are:

[0020] In the present technical solution, when the valve stem drives the valve core to move in the up and down direction in the steam turbine governing valve, the arc-shaped rod and the first groove body are slidably matched in the up and down direction, and the limiting post and the second groove body are slidably matched in the up and down direction, changing the constraint conditions of the valve stem and the valve core, avoiding the rotation of the valve stem and the rotation of the valve core during the operation of the governing valve, improving the structural and anti-vibration capabilities; at the same time, preventing the relative rotation of the valve stem and the valve core, and avoiding the loosening of the assembly of the valve stem and the valve core. Description of the Drawings

[0021] Figure 1 The figure shows a schematic structural diagram of a steam turbine governing valve in Embodiment 1;

[0022] Figure 2 The figure shows Figure 1 a magnified schematic diagram of Structure A in

[0023] Figure 3 The figure shows a top view schematic diagram of a disk body in Embodiment 1;

[0024] Figure 4 The figure shows schematic diagrams of two states of an arc-shaped rod inside an arc-shaped through hole in Embodiment 1.

[0025] Reference numerals: valve housing 11; valve housing cavity 12; air inlet 13; air outlet 14; valve cover 21; valve seat 22; valve seat cavity 221; first installation groove 23; limit through hole 24; threaded hole 25; valve core 31; first groove body 32; valve rod 41; disk body 42; second groove body 43; filter screen 51; limit post 61; second installation groove 611; installation through hole 612; arc-shaped through hole 613; long rod 62; screw rod 63; magnet 64; arc-shaped rod 65. Detailed Embodiments

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments.

[0027] Embodiment 1

[0028] As shown in Figure 1 , Figure 2 , Figure 3 , Figure 4 , a steam turbine governing valve includes:

[0029] a valve housing 11 with an upper end opening, the valve housing 11 having an air inlet 13 and an air outlet 14, and a valve housing cavity 12 formed at the intersection of the extended air inlet 13 and air outlet 14;

[0030] a valve cover 21 covering the upper end opening of the valve housing 11, the lower end of the valve cover 21 extending downward into the valve housing cavity 12 to form a valve seat 22, the middle of the valve seat 22 having a valve seat cavity 221 with a lower end opening, a plurality of arc-shaped rods 65 provided on the side wall of the valve seat cavity 221, and a limit post 61 provided on the valve cover 21;

[0031] The valve core 31 that is slidably mated with the valve seat cavity 221 has a valve rod 41 threadedly assembled at its upper end. The valve rod 41 extends upward through the valve cover 21 and is slidably and sealingly mated with the valve cover 21. A first groove 32 is provided on the valve core 31 and is distributed along the axial direction of the valve rod 41. The number of the first grooves 32 matches the number of the arc-shaped rods 65. A disk body 42 is sleeved on a section of the valve rod 41 outside the valve cover 21, and a second groove 43 is formed on the disk body 42;

[0032] One end of the valve rod 41 outside the valve cover 21 is connected to the piston shaft of an external oil motor through a coupling. The valve rod 41 drives the valve core 31 to move in the axial direction of the valve rod 41. At this time, the arc-shaped rod 65 is located inside the first groove 32 and is slidably mated with it. The limit post 61 axially penetrates the second groove 43. When the valve core 31 moves to the lowest position, it is sealingly mated with the air outlet 14.

[0033] In the steam turbine governing valve of this technical solution, steam enters from the steam inlet 13 and is discharged from the steam outlet 14. The external oil motor controls the valve rod 41 to drive the valve core 31 to move in the axial direction of the valve rod 41 (in the up and down direction), changing the distance between the valve core 31 and the steam outlet 14. When the valve core 31 moves to the lowest position, it is sealingly mated with the steam outlet 14, controlling the opening or closing of the governing valve, thereby regulating the steam flow rate entering the steam turbine.

[0034] In this technical solution, when the valve rod 41 drives the valve core 31 to move in the up and down direction, the arc-shaped rod 65 and the first groove 32 are slidably mated in the up and down direction, and the limit post 61 and the second groove 43 are slidably mated in the up and down direction, changing the constraint conditions of the valve rod 41 and the valve core 31, avoiding the rotation of the valve rod 41 and the valve core 31 during the operation of the governing valve, improving the structural and anti-vibration capabilities; at the same time, preventing the relative rotation of the valve rod 41 and the valve core 31 and avoiding the loosening of the assembly of the valve rod 41 and the valve core 31.

[0035] As limit members to prevent the rotation of the valve core 31 and the valve rod 41, during long-term use, the arc-shaped rod 65 and the limit post 61 may be deformed under force. To ensure the working performance of the governing valve, after this situation occurs, the limit members need to be disassembled and replaced. Therefore, as Figure 1 、 Figure 2 、 Figure 3 、 Figure 4As shown in the figure, an installation groove 23 with an open upper end is provided on the valve cover 21, and a limiting through hole 24 connecting the installation groove 23 and the valve seat cavity 221. A limiting column 61 is hermetically fitted in the installation groove 23. An installation groove two 611 with an open upper end and an arc-shaped through hole 613 connecting the installation groove two 611 and the outside of the side wall of the limiting column 61 are provided on the limiting column 61. An arc-shaped rod 65 is slidably fitted in the arc-shaped through hole 613, and the arc-shaped through hole 613 and the arc-shaped rod 65 are concentrically arranged. A long rod 62 is assembled in the installation groove two 611. When the long rod 62 is inserted into the installation groove two 611, one end of the arc-shaped rod 65 located inside the installation groove two 611 is squeezed until one end of the arc-shaped rod 65 located outside the installation groove two 611 penetrates the arc-shaped through hole 613 and abuts against the side wall of the valve seat cavity 221.

[0036] Reference Figure 4 , when assembling the limiting member, rotate the arc-shaped rod 65 clockwise in the arc-shaped through hole 613 until the right end of the arc-shaped rod 65 enters the inside of the arc-shaped through hole 613. Insert the limiting column 61 into the inside of the installation groove one 23, and the arc-shaped rod 65 corresponds to the limiting through hole 24. Insert the long rod 62 into the installation groove two 611. The left end of the arc-shaped rod 65 is squeezed, driving the arc-shaped rod 65 to rotate counterclockwise in the arc-shaped through hole 613 until the right end of the arc-shaped rod 65 penetrates the limiting through hole 24 and enters the groove body one 32 and then abuts against the side wall of the valve seat cavity 221.

[0037] In this technical solution, the limiting member is detachably arranged. After the limiting member is deformed under force, it is disassembled and replaced to ensure the working performance of the throttle valve. The limiting column 61 is a limiting member for the valve stem 41. The long rod 62 fills the middle part of the limiting column 61 to ensure the overall strength of the limiting column 61 and reduce the possibility of deformation under force. The arc-shaped rod 65 is a limiting member for the valve core 31. The limiting column 61 supports the middle part of the arc-shaped rod 65. The long rod 62 limits the position of the left end of the arc-shaped rod 65. The side wall of the valve seat cavity 221 limits the position of the right end of the arc-shaped rod 65 to complete the fixation of the position of the arc-shaped rod 65. The setting that the arc-shaped rod 65 penetrates the limiting through hole 24 limits the middle part of the arc-shaped rod 65 to prevent it from rotating and ensures the overall strength of the arc-shaped rod 65.

[0038] To solve the problem of installing the limiting column 61 and the long rod 62 inside the installation groove 23, as Figure 2 , Figure 4 shown, an installation through hole 612 connecting the installation groove two 611 and the outside of the bottom wall of the limiting column 61 is provided on the limiting column 61. A threaded hole 25 is provided on the bottom of the installation groove 23. A screw rod 63 is connected to the lower end of the long rod 62. One of a variety of slots such as a flat slot and a cross slot is provided at the end of the long rod 62 to facilitate the rotation operation of the long rod 62.

[0039] When performing the installation operation, the limit post 61 is inserted into the interior of the installation groove 23, the long rod 62 is inserted into the limit post 61, and the screw rod 63 passes through the installation through hole 612 and is in threaded cooperation with the threaded hole 25 until the limit post 61, the long rod 62, and the installation groove 23 are in close contact, realizing the fixation of the relative positions among the limit post 61, the long rod 62, and the installation groove 23.

[0040] To further improve the detachable setting of the limiting member, as Figure 2 , Figure 4 shown, a magnet 64 is connected to the end of the screw rod 63, and an armature is provided at the end of the arc-shaped rod 65 located inside the installation groove two 611. When disassembling the limiting member, first rotate the long rod 62 to disengage the screw rod 63 from the threaded hole 25, and lift the long rod 62 from the installation groove two 611. At this time, after the magnet 64 passes over the arc-shaped rod 65, the magnet 64 adsorbs the arc-shaped rod 65 and drives the arc-shaped rod 65 to rotate clockwise in the arc-shaped through hole 613 until the end of the arc-shaped rod 65 located outside the installation groove two 611 enters the interior of the arc-shaped through hole 613, and then completely remove the long rod 62 from the installation groove two 611.

[0041] As Figure 3 shown, anti-rotation ribs are provided on the outer side wall of the limit post 61. At least one anti-rotation rib is provided, and four anti-rotation ribs are provided in this embodiment, so that the overall shape of the limit post 61 presents the image of a quadrangular prism, and the installation groove 23 matches the outer shell 6.

[0042] The setting that the overall shape of the limit post 61 is a quadrangular prism facilitates determining the relative positions of the installation groove 23 and the outer shell 6 during assembly, ensuring the accuracy of the position of the arc-shaped rod 65 during installation; at the same time, it enables the outer shell 6 to have an anti-rotation function inside the installation groove 23, avoiding the situation where the rotation of the outer shell 6 increases the force on the arc-shaped rod 65 and ensuring the service performance of the arc-shaped rod 65.

[0043] As Figure 1 shown, a filter screen 51 is provided between the valve housing 11 and the valve cover 21, and the valve seat 22 and the valve core 31 are both located inside the filter screen 51. The setting of the filter screen 51 is used to filter impurities in the steam to prevent impurities from entering the interior of the throttle valve and causing component wear; at the same time, the setting of the filter screen 51 connects the lower parts of the valve cover 21 and the valve housing 11. When the valve stem 41 is vibrated during the operation of the valve, the force is transmitted to the valve cover 21, the valve cover 21 transmits it to the upper part of the valve housing 11, and the valve cover 21 transmits it to the lower part of the valve housing 11 through the filter screen 51 again, making the entire throttle valve form a force-receiving whole and avoiding the situation where the valve stem 41 is vibrated alone and ensuring the working performance of the valve stem 41.

[0044] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them.

Claims

1. Steam turbine valve, characterized in that: include: A valve housing (11) with an opening at the upper end, the valve housing (11) having an air inlet (13) and an air outlet (14), wherein a valve housing cavity (12) is formed at a position where the air inlet (13) and the air outlet (14) extend and intersect; A valve cover (21) covers the upper opening of the valve housing (11), the lower end of the valve cover (21) extends downward into the valve housing cavity (12) to form a valve seat (22), the middle of the valve seat (22) has a valve seat cavity (221) with a lower opening, a plurality of arc-shaped rods (65) are arranged on the side wall of the valve seat cavity (221), and a limiting column (61) is arranged on the valve cover (21); A valve core (31) slidably matched with the valve seat cavity (221), the upper end of the valve core (31) is threadedly assembled with a valve stem (41), the valve stem (41) extends upwardly through the valve cover (21) and is slidably sealed with the valve cover (21), the valve core (31) is provided with a groove body (32) distributed along the axial direction of the valve stem (41), the number of the groove bodies (32) matches the number of the arc rods (65), a section of the valve stem (41) located outside the valve cover (21) is sleeved with a disk body (42), and the disk body (42) is provided with a groove body (43); One end of the valve stem (41) located outside the valve cover (21) is connected to the piston shaft of the external oil motor through a coupling. The valve stem (41) drives the valve core (31) to move in the axial direction of the valve stem (41). At this time, the arc rod (65) is located inside the groove body (32) and slides therewith. The limit column (61) penetrates the groove body (43) in the axial direction. When the valve core (31) moves to the lowest position, it seals and cooperates with the air outlet (14).

2. The steam turbine regulating valve according to claim 1, characterized in that: The valve cover (21) is provided with a mounting groove (23) with an upper end opening, a limiting through hole (24) connecting the mounting groove (23) and the valve seat cavity (221), the mounting groove (23) is sealed with a limiting column (61), the limiting column (61) is provided with a mounting groove 2 (611) with an upper end opening, an arc-shaped through hole (613) connecting the mounting groove 2 (611) and the outside of the side wall of the limiting column (61), the arc-shaped through hole (613) is slidably matched with an arc-shaped rod (65), and the arc-shaped through hole (613) and the arc-shaped rod (65) are concentrically arranged; A long rod (62) is installed in the second installation groove (611). When the long rod (62) is installed in the second installation groove (611), the end of the arc rod (65) located inside the second installation groove (611) is squeezed until the end of the arc rod (65) located outside the second installation groove (611) passes through the arc through hole (613) and then contacts the side wall of the valve seat cavity (221).

3. The steam turbine regulating valve according to claim 2, characterized in that: The limiting column (61) is provided with a mounting through hole (612) connecting the second mounting groove (611) and the outside of the bottom wall of the limiting column (61); the bottom of the mounting groove (23) is provided with a threaded hole (25); the lower end of the long rod (62) is connected with a screw rod (63); the screw rod (63) passes through the mounting through hole (612) and is threadedly matched with the threaded hole (25).

4. The steam turbine regulating valve according to claim 3, characterized in that: The end of the screw rod (63) is connected to a magnet (64), and the end of the arc rod (65) located inside the second mounting groove (611) is provided with an armature; When the long rod (62) is taken out of the limiting column (61), the magnet (64) attracts the arc rod (65) to drive the arc rod (65) to rotate in the arc through hole (613) until the end of the arc rod (65) located outside the second installation groove (611) enters the interior of the arc through hole (613).

5. The steam turbine regulating valve according to claim 2, characterized in that: An anti-rotation edge is provided on the outer side wall of the limiting column (61), and the mounting groove (23) matches the housing (6).

6. The steam turbine regulating valve according to claim 1, characterized in that: A filter screen (51) is provided between the valve housing (11) and the valve cover (21), and the valve seat (22) and the valve core (31) are both located inside the filter screen (51).

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