Adjusting type sliding plate valve for boiler water supply

Abstract

The utility model relates to an adjusting type sliding plate valve for boiler water supply, which comprises a valve body, a medium passing cavity is arranged in the valve body, the medium passing cavity extends along the inlet end of the valve body and the outlet end of the valve body, and the central axis of the inlet end of the valve body, the central axis of the outlet end of the valve body and the central axis of the medium passing cavity are located on the same axis. Two parallel valve seats are arranged in the medium passing cavity, a sliding plate is arranged between the two valve seats, a valve deck is arranged above the sliding plate, valve rods are arranged on the valve deck and the sliding plate, throttling holes are correspondingly formed in the two valve seats, and the throttling holes are communicated with the valve deck. And each throttling hole comprises a first variable-diameter section, an equal-diameter section, a second variable-diameter section, a third variable-diameter section and a fourth variable-diameter section which are sequentially connected from bottom to top. And the throttling assembly is simple in structure and convenient to maintain. And the device is convenient to adjust and use, and has a wide market prospect.

Description

Technical Field

[0001] The utility model relates to the field of boiler feed water valves, in particular to a regulating slide valve for boiler feed water. Background Art

[0002] Industrial boilers are important power sources in production and life, and the boiler water supply system is one of the core supporting components of industrial boilers. The task of the boiler water supply system is to continuously deliver boiler water to the steam drum of the industrial boiler and maintain the water level of the steam drum of the industrial boiler within the preset range. GB / T1576-2018 "Industrial Boiler Water Quality" makes detailed provisions on the types and technical requirements of industrial boiler water sources. Among them, softened water and desalted water can be used as water sources for boiler water supply; the softened water is water after all or most of the calcium and magnesium ions are removed; the desalted water is the finished water obtained by using various water treatment processes to remove impurities in water such as suspended matter, colloids, anions and cations.

[0003] Among them, GB / T1576-2018 "Industrial Boiler Water Quality" makes detailed provisions for dissolved oxygen in softened water and desalted water as the water source for boiler feed water. The boiler feed water system uses the deoxygenation equipment on the boiler feed water system to deoxygenate softened water or desalted water, and most of the deoxygenation equipment uses heating to deoxygenate softened water or desalted water. The principle is: in the deaerator volume, the total pressure of the gas on the water surface should be equal to the sum of the partial pressure of water vapor and the partial pressure of various gases dissolved in water. The feed water is heated at a constant pressure in the deaerator, the evaporation process of water is continuously strengthened, the partial pressure of steam on the water surface is gradually increased, and the partial pressure of other gases dissolved in the water is continuously reduced. When the water is heated to the saturation temperature under the deaerator pressure, the water begins to boil, the partial pressure of water vapor is close to the total pressure on the water surface, and the partial pressure of other gases is close to zero. The gas dissolved in the water will escape from the water and be discharged by the deaerator exhaust door, so that the air and other gases are removed.

[0004] The deoxygenated water is then pumped and then transported to the drum of the industrial boiler after adjusting the flow rate, thus completing the entire boiler feed water transportation process. Among them, the corresponding booster pump should be installed on the pipeline after the deoxygenation equipment to complete the pumping action of the deoxygenated water, and the deoxygenated pumped water needs to be adjusted by both the regulating valve and the stop valve. In this process, the regulating valve only plays the function of adjusting the medium flow rate, while the stop valve realizes the shut-off function. The main reason is that although the regulating valve can also realize the shut-off function, the pumped water not only has a higher pressure, but also has a higher temperature due to heating and deoxygenation. After the flow rate is adjusted by the throttling component in the regulating valve, it is inevitable that cavitation will be caused to the corresponding throttling component, and the severity of cavitation depends on the size of the throttling amount. Undoubtedly, directly reaching the preset adjustment range from the off state will cause a large throttling of the medium in the part of the process where the regulating valve just moves from the off state to the target adjustment position, thereby making the cavitation phenomenon more serious. Therefore, a corresponding stop valve is required to realize the shut-off function, and the regulating valve only needs to complete the medium flow regulation function. The throttling of commercially available regulating valves is achieved by relying on throttling components, which include throttling cages and throttling orifices. Both the throttling cages and throttling orifices are throttling components with relatively complex structures. Long-term regulating valves use throttling components to adjust the flow of the corresponding boiler feed water. The corresponding throttling components will cause their throttling effect to decrease due to long-term cavitation, and thus require frequent maintenance or replacement of the throttling components. Throttling components such as throttling cages or throttling orifices have a relatively high market value due to their complex structures. Therefore, within the service life cycle of the regulating valve, the proportion of daily maintenance and repair costs has remained high.

[0005] In summary, there is a motivation for improvement in the field of valves produced for boiler feed water, and a valve with both regulating and shut-off functions is developed; first, the initial investment cost of using valves on the downstream pipeline of the booster pump after the deaerator is reduced; secondly, the flow regulating component structure of the valve is simple, and even if cavitation occurs, it will not cause serious structural damage and become unrepairable, thereby reducing the maintenance cost invested in the later use of the valve to meet market demand. Summary of the invention

[0006] In view of the deficiencies in the prior art, the utility model provides a boiler feed water regulating slide valve which can realize regulating and shutoff functions and has a throttling component with a simple structure and is easy to maintain, so as to overcome the defects in the prior art.

[0007] The technical scheme adopted by the utility model is: a regulating slide valve for boiler feed water, comprising a valve body, a medium passing cavity is arranged in the valve body, the medium passing cavity extends along the inlet end and the outlet end of the valve body, the central axis of the inlet end of the valve body, the central axis of the outlet end of the valve body and the central axis of the medium passing cavity are located on the same axis, two valve seats parallel to each other are arranged in the medium passing cavity, a slide plate is arranged between the two valve seats, a valve cover is arranged above the slide plate, a valve stem is arranged on the valve cover and the slide plate, throttling holes are correspondingly arranged in the two valve seats, each throttling hole includes a first diameter reducing section, a constant diameter section, a second diameter reducing section, a third diameter reducing section and a fourth diameter reducing section which are connected in sequence from bottom to top, the aperture of the first diameter reducing section, the aperture of the second diameter reducing section and the aperture of the third diameter reducing section all gradually increase from bottom to top, and the aperture of the fourth diameter reducing section gradually decreases from bottom to top.

[0008] Preferably, a height indicating disk is arranged on the valve stem above the valve cover, a ruler is arranged on one side of the height indicating disk, and a graduation layer is arranged on the side of the ruler close to the height indicating disk.

[0009] Preferably, the thickness of the outer end of the height indicating disk gradually decreases as the height indicating disk gradually approaches the scale layer.

[0010] Preferably, a packing sealing groove is opened on the top of the valve cover, a packing gasket is arranged in the packing sealing groove, a packing gland is arranged above the packing gasket, and a first sealing packing and a second sealing packing are alternately arranged in the packing sealing groove between the packing gasket and the packing gland along the direction from the packing gasket to the packing gland, and the packing gasket, the first sealing packing, the second sealing packing and the packing gland are all mounted on the valve stem.

[0011] Preferably, a first connecting ring is provided on the outer side of the valve cover, a connecting wing plate is provided on the outer side of the first connecting ring, a packing pressure plate is provided on the valve stem above the packing gland, the packing gland and the packing pressure plate are movably connected, and a first bolt is provided on the packing pressure plate and the connecting wing plate.

[0012] Preferably, a third sealing packing is arranged between the valve body and the valve cover, a packing pressure ring is arranged above the third sealing packing, a limiting block is arranged in the valve body above the packing pressure ring, a valve cover pressure plate is arranged above several limiting blocks, and second bolts are arranged on the valve cover pressure plate and the valve cover. Several second bolts and limiting blocks are used, and several limiting blocks and several second bolts are distributed in a star shape on the outside of the center axis of the valve stem.

[0013] Preferably, a guide block is provided on one end of the valve stem facing the slide plate, a guide sleeve is provided on the outer side of the guide block, the bottom end of the guide sleeve is installed on the top end of the slide plate, the bottom of the guide block and the bottom of the inner cavity of the guide sleeve are movably connected, and the bottom of the guide block adopts an arc surface structure.

[0014] The beneficial effects of the utility model are as follows: in the closed position, the slide plate of the utility model utilizes the pressure of the upstream medium to force the slide plate to be close to the valve seat on the side of the outlet end of the valve body, thereby sealing the gap between the two throttling holes to realize the shut-off function; as the position of the slide plate is different, the two throttling holes below the slide plate are prompted to throttle the passing fluid medium, thereby realizing the function of regulating the flow rate of the fluid medium. Since the throttling function is realized by the two throttling holes and the bottom end of the slide plate, the center axis of the inlet end of the valve body, the center axis of the outlet end of the valve body and the center axis of the medium passing cavity are located on the same axis, and the flow direction will not change in the process of successively passing through the inlet end of the valve body, the medium passing cavity and the outlet end of the valve body, so that the position of cavitation is relatively concentrated. Even if partial cavitation occurs at the bottom end of the slide plate, it has little effect on regulation and shut-off. Combined with the throttling holes only opened on each valve seat, the structure of the throttling component is relatively simple. Even if cavitation occurs, it only needs to recalibrate the opening position of the slide plate after maintenance, so that water can be supplied to industrial boilers in different states again, which is convenient for use. The utility model has the advantages of simple structure, convenient operation, ingenious design, greatly improved working efficiency, good social and economic benefits, and is a product that is easy to promote and use. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural schematic diagram of the utility model.

[0016] Figure 2 for Figure 1 A partial enlarged schematic diagram of detail A.

[0017] Figure 3 It is a structural schematic diagram of the valve seat of the utility model. DETAILED DESCRIPTION

[0018] like Figures 1 to 3As shown, a regulating slide valve for boiler feed water comprises a valve body 1, a medium passage cavity is arranged in the valve body 1, the medium passage cavity extends along the inlet end and the outlet end of the valve body 1, the center axis of the inlet end of the valve body 1, the center axis of the outlet end of the valve body 1 and the center axis of the medium passage cavity are located on the same axis, two valve seats 2 parallel to each other are arranged in the medium passage cavity, a slide plate 3 is arranged between the two valve seats 2, the two valve seats 2 and the slide plate 3 are made of martensitic stainless steel, and the slide plate 3 is made of a material that can be made along the gap between the two valve seats 2 A plate-like structure for sliding movement, a valve cover 4 is arranged above the slide plate 3, a valve stem 5 is arranged on the valve cover 4 and the slide plate 3, the valve stem 5 adopts a rod-like structure that can slide along the central axis of the valve stem 5, and a throttling hole 6 is correspondingly arranged in each of the two valve seats 2. The number of the throttling holes 6 is two, and the two throttling holes 6 are located at the same height. The bottom of the slide plate 3 is located below the two throttling holes 6; each throttling hole 6 includes a first diameter-reducing section, a constant diameter section, a second diameter-reducing section, a third diameter-reducing section and a fourth diameter-reducing section that are connected in sequence from bottom to top, and the aperture of the first diameter-reducing section, the aperture of the first diameter-reducing section, the aperture of the second diameter-reducing section, the aperture of the third diameter-reducing section, and the aperture of the fourth diameter-reducing section are connected in sequence. The aperture of the second diameter-changing section and the aperture of the third diameter-changing section are gradually increased from bottom to top, so that when the slide plate 3 performs an opening or closing action on the first diameter-changing section, the second diameter-changing section or the third diameter-changing section, the pressure difference between the upstream of the slide plate 3 and the downstream of the slide plate 3 can be uniformly changed, and the aperture of the fourth diameter-changing section is gradually reduced from bottom to top, so that when the slide plate 3 performs an opening or closing action on the first diameter-changing section, the second diameter-changing section, the third diameter-changing section or the fourth diameter-changing section, the resistance encountered by the slide plate 3 can be uniformly changed. , so that the slide plate 3 can realize uniform motion when the first variable diameter section, the second variable diameter section, the third variable diameter section or the fourth variable diameter section performs an opening or closing action; the equal diameter section adopts a rectangular hole structure, the maximum aperture of the first variable diameter section is equal to the aperture of the equal diameter section, the minimum aperture of the second variable diameter section is equal to the aperture of the equal diameter section, the maximum aperture of the second variable diameter section is equal to the minimum aperture of the third variable diameter section, and the maximum aperture of the third variable diameter section is equal to the maximum aperture of the fourth variable diameter section.

[0019] A height indicator disk 7 is arranged on the valve stem 5 above the valve cover 4, a scale 8 is arranged on one side of the height indicator disk 7, and a graduation layer 9 is arranged on the side of the scale 8 close to the height indicator disk 7; when the valve stem 5 performs an opening action or a closing action, the valve stem 5 drives the height indicator disk 7 to move, and the height indicator disk 7 changes position, and the graduation layer 9 arranged on the scale 8 is used to feedback the distance change of the height indicator disk 7, thereby feedback the moving distance of the slide plate 3, and then judge the size of the opening of the throttle hole 6. Furthermore, the thickness of the outer end of the height indicator disk 7 gradually decreases as the height indicator disk 7 gradually approaches the graduation layer 9, so that it is more convenient to use the outer end of the height indicator disk 7 to feedback the relative position of the height indicator disk 7 on the graduation layer 9.

[0020] A packing sealing groove 10 is provided at the top of the valve cover 4, a packing gasket 11 is provided in the packing sealing groove 10, a packing gland 12 is provided above the packing gasket 11, a first sealing packing 13 and a second sealing packing 14 are alternately provided in the packing sealing groove 10 between the packing gasket 11 and the packing gland 12 in sequence along the direction from the packing gasket 11 to the packing gland 12, the packing gasket 11, the first sealing packing 13, the second sealing packing 14 and the packing gland 12 are all sleeved on the valve stem 5, the first sealing packing 13 adopts an annular structure made of flexible graphite, the second sealing packing 14 adopts an annular structure made of braided graphite, the number of the first sealing packing 13 and the number of the second sealing packing 14 are both several, so that the mutual extrusion between the adjacent first sealing packings 13 and the second sealing packings 14 causes the first sealing packing 13 or the second sealing packing 14 to deform, thereby causing the gap between the valve cover 4 and the valve stem 5 to be reduced, thereby reducing the leakage of the medium from the gap between the valve cover 4 and the valve stem 5.

[0021] Furthermore, a first connecting ring 15 is provided on the outer side of the valve cover 4, a connecting wing plate 16 is provided on the outer side of the first connecting ring 15, a packing pressure plate 17 is provided on the valve stem 5 above the packing gland 12, the top of the packing gland 12 adopts a truncated cone tubular structure, the shape of the bottom part of the packing pressure plate 17 matches the shape of the top of the packing gland 12, the packing gland 12 and the packing pressure plate 17 are movably connected, and the packing pressure plate 17 and the connecting wing plate 16 are provided with a first bolt 18; the number of the first bolts 18 is several, each of the first bolts 18 is correspondingly installed with a connecting wing plate 16, and the several connecting wing plates 16 are evenly spaced in a star shape. The packing gland 12 is provided with a nut on each of the first bolts 18 above the packing plate 17, and the nuts are movably connected with the packing plate 17, so that the packing plate 17 can obtain a driving force to move toward the packing gland 12 by tightening the nuts. Under the action of the driving force and the guidance generated by the partial shape of the bottom of the packing plate 17 and the shape of the top of the packing gland 12, the packing gland 12 obtains a downward driving force, thereby causing the first sealing packing 13 and / or the second sealing packing 14 to deform, thereby reducing the gap between the valve cover 4 and the valve stem 5.

[0022] A third sealing packing 19 is arranged between the valve body 1 and the valve cover 4, a packing pressure ring 20 is arranged above the third sealing packing 19, a limiting block 21 is arranged in the valve body 1 above the packing pressure ring 20, a valve cover pressure plate 22 is arranged above a plurality of limiting blocks 21, a second bolt 23 is arranged on the valve cover pressure plate 22 and the valve cover 4, the valve cover 4 and the second bolt 23 are threadedly connected, the second bolt 23 and the valve cover pressure plate 22 are movably connected, the number of the second bolt 23 and the limiting block 21 is several, and the plurality of limiting blocks 21 and the plurality of second bolts 23 are all distributed in a star shape outside the central axis of the valve stem 5. The third sealing packing 19 is an annular structure made of flexible graphite, the inner cavity diameter at the bottom of the third sealing packing 19 gradually increases as the height of the third sealing packing 19 decreases, and the partial structure of the valve cover 4 matches the shape of the inner cavity at the bottom of the third sealing packing 19. The packing ring 20 adopts an annular structure, the bottom surface of the packing ring 20 is movably connected to the top surface of the third sealing packing 19, the bottom surfaces of several limiting blocks 21 are movably connected to the top surface of the packing ring 20, and a limiting groove 29 is provided in the valve body 1 above the valve cover 4. The limiting groove 29 adopts an annular structure, and the tops of several limiting blocks 21 are partially installed in the limiting groove 29. The cross section of each limiting block 21 adopts an L-shaped structure. The top surfaces of several limiting blocks 21 are movably connected to the valve cover pressure plate 22; so that it is convenient to tighten several second bolts 23, and the valve cover 4 can move toward the direction of the third sealing packing 19 under the limit formed by several limiting blocks 21, and the third sealing packing 19 is deformed again under the limit of the packing ring 20, thereby reducing the gap between the valve cover 4 and the valve body 1 and reducing the leakage of the medium from the gap between the valve cover 4 and the valve body 1.

[0023] The valve stem 5 is provided with a guide block 24 on one end facing the slide plate 3, a guide sleeve 25 is provided on the outer side of the guide block 24, the bottom end of the guide sleeve 25 is mounted on the top end of the slide plate 3, the bottom of the guide block 24 is movably connected to the bottom of the inner cavity of the guide sleeve 25, the bottom of the guide block 24 adopts an arc surface structure, and the bottom of the inner cavity of the guide sleeve 25 adopts a plane structure; thus, it is convenient to utilize the structure of the bottom surface of the guide block 24 combined with the shape of the bottom of the inner cavity of the guide sleeve 25 to guide the slide plate 3 when the slide plate 3 reaches the closed state, so that it is convenient for the slide plate 3 to reach the closed position. A second connecting ring 26 is provided on the top end of the valve body 1, and a connecting bracket 27 is provided on the second connecting ring 26, the scale 8 is mounted on the connecting bracket 27, and a driving motor 28 is provided on the top end of the connecting bracket 27, and the connecting bracket 27 is connected to the valve stem 5 in a transmission manner.

[0024] The usage of this product is as follows: Figures 1 to 3As shown, after the product is installed in the preset installation position, when the product is in the closed state, the bottom of the slide plate 3 is located below the two throttling holes 6, and the upstream medium presses the slide plate 3 against the valve seat 2 on the outlet side of the valve body 1 to seal the gap between the two throttling holes 6, thereby realizing the shut-off function.

[0025] During the trial operation of the industrial boiler, the amount of water supply required for the steam drum of the industrial boiler is not large. The driving motor 28 drives the valve stem 5 to move upward, thereby driving the slide plate 3 and the height indicator disk 7 to make corresponding movements. After the height indicator disk 7 reaches the first preset position at the rising position of the scale layer 9, at this time, the upstream medium is throttled for the first time through the first reducing section and the equal diameter section in the throttling hole 6 on the side close to the inlet end of the valve body 1 and is transported to the medium passing through the cavity below the slide plate 3; then, the medium below the slide plate 3 is transported through the cavity to the first reducing section and the equal diameter section in the throttling hole 6 on the side close to the outlet end of the valve body 1 for the second throttling and then transported to the steam drum of the boiler, thereby maintaining the water supply required during the trial operation of the industrial boiler.

[0026] During the normal operation of the industrial boiler, the amount of water supplied to the steam drum of the industrial boiler is maintained within a normal range, and the driving motor 28 drives the valve stem 5 to move upward, thereby driving the slide plate 3 and the height indicator disk 7 to make corresponding movements. After the height indicator disk 7 reaches the second preset position at the rising position of the scale layer 9, at this time, the upstream medium is throttled for the first time through the first reducing section, the equal diameter section, the second reducing section and the third reducing section in the throttling hole 6 on the side of the inlet end of the valve body 1 and is transported to the medium passing through the cavity below the slide plate 3; then, the medium below the slide plate 3 is transported through the cavity to the first reducing section, the equal diameter section, the second reducing section and the third reducing section in the throttling hole 6 on the side of the outlet end of the valve body 1 for the second throttling and then transported to the steam drum of the boiler, thereby maintaining the water supply required during the normal operation of the industrial boiler.

[0027] When an abnormal condition occurs during the operation of an industrial boiler and a large amount of water needs to be continuously transported, the driving motor 28 drives the valve stem 5 to move upward, thereby driving the slide plate 3 and the height indicator disk 7 to make corresponding movements. After the height indicator disk 7 reaches the third preset position at the rising position of the scale layer 9, at this time, the upstream medium is throttled for the first time through the first reducing section, the equal diameter section, the second reducing section, the third reducing section and the fourth reducing section in the throttling hole 6 on the side of the inlet end of the valve body 1 and transported to the medium passing through the cavity below the slide plate 3; then, the medium below the slide plate 3 is transported through the cavity to the first reducing section, the equal diameter section, the second reducing section, the third reducing section and the fourth reducing section in the throttling hole 6 on the side of the outlet end of the valve body 1 for the second throttling and then transported to the steam drum of the boiler, thereby maintaining the continuous transportation of a large amount of water.

[0028] Through this embodiment, the slide plate 3 of this product uses the pressure of the upstream medium in the closed position to force the slide plate 3 to be close to the valve seat 2 on the side of the outlet end of the valve body 1, thereby sealing the gap between the two throttling holes 6 to achieve the shut-off function; as the position of the slide plate 3 is different, the two throttling holes 6 below the slide plate 3 are prompted to throttle the passing fluid medium, thereby achieving the function of regulating the flow of the fluid medium. Since the throttling function is achieved by the two throttling holes 6 and the bottom end of the slide plate 3, combined with the center axis of the inlet end of the valve body 1, the center axis of the outlet end of the valve body 1 and the medium The central axis of the cavity is located on the same axis. In the process of successively passing through the inlet end of the valve body 1, the medium passing through the cavity and the outlet end of the valve body 1, the flow direction will not change, so that the position of cavitation is relatively concentrated. Even if partial cavitation occurs at the bottom end of the slide plate 3, it has little effect on regulation and shutdown. Combined with the throttling hole 6 only opened on each valve seat 2, the structure of the throttling component is relatively simple. Even if cavitation occurs, it only needs to recalibrate the opening position of the slide plate 3 after maintenance, so that water can be supplied to industrial boilers in different states again, which is convenient for use.

[0029] The embodiments described above are only preferred embodiments of the present invention and are not intended to limit the scope of implementation of the present invention. Therefore, any equivalent changes or modifications made based on the structures, features and principles described in the patent scope of the present invention should be included in the patent application scope of the present invention.

Claims

1. A boiler feed water regulating slide valve, characterized in that: The valve body (1) comprises a valve body (1), wherein a medium passage cavity is arranged in the valve body (1), wherein the medium passage cavity extends along the inlet end of the valve body (1) and the outlet end of the valve body (1), wherein the central axis of the inlet end of the valve body (1), the central axis of the outlet end of the valve body (1) and the central axis of the medium passage cavity are located on the same axis, wherein two valve seats (2) parallel to each other are arranged in the medium passage cavity, wherein a slide plate (3) is arranged between the two valve seats (2), wherein a valve cover (4) is arranged above the slide plate (3), and wherein the valve A valve stem (5) is provided on the cover (4) and the slide plate (3), and a throttling hole (6) is correspondingly provided in each of the two valve seats (2). Each throttling hole (6) comprises a first diameter-changing section, a constant diameter section, a second diameter-changing section, a third diameter-changing section and a fourth diameter-changing section which are connected in sequence from bottom to top. The aperture of the first diameter-changing section, the aperture of the second diameter-changing section and the aperture of the third diameter-changing section all gradually increase from bottom to top, and the aperture of the fourth diameter-changing section gradually decreases from bottom to top.

2. The regulating slide valve for boiler feed water according to claim 1, characterized in that: A height indicator disk (7) is arranged on the valve stem (5) above the valve cover (4), a scale (8) is arranged on one side of the height indicator disk (7), and a graduation layer (9) is arranged on the side of the scale (8) close to the height indicator disk (7).

3. The regulating slide valve for boiler feed water according to claim 2, characterized in that: The thickness of the outer end of the height indicating disc (7) gradually decreases as the height indicating disc (7) gradually approaches the scale layer (9).

4. The regulating slide valve for boiler feed water according to claim 1, characterized in that: A packing sealing groove (10) is provided at the top of the valve cover (4), a packing gasket (11) is provided in the packing sealing groove (10), a packing gland (12) is provided above the packing gasket (11), a first sealing packing (13) and a second sealing packing (14) are alternately provided in the packing sealing groove (10) between the packing gasket (11) and the packing gland (12) in a direction from the packing gasket (11) to the packing gland (12), and the packing gasket (11), the first sealing packing (13), the second sealing packing (14) and the packing gland (12) are all mounted on the valve stem (5).

5. The regulating slide valve for boiler feed water according to claim 4, characterized in that: A first connecting ring (15) is arranged on the outer side of the valve cover (4), a connecting wing plate (16) is arranged on the outer side of the first connecting ring (15), a packing pressure plate (17) is arranged on the valve stem (5) above the packing gland (12), the packing gland (12) and the packing pressure plate (17) are movably connected, and a first bolt (18) is arranged on the packing pressure plate (17) and the connecting wing plate (16).

6. The regulating slide valve for boiler feed water according to claim 1, characterized in that: A third sealing packing (19) is arranged between the valve body (1) and the valve cover (4), a packing pressure ring (20) is arranged above the third sealing packing (19), a limiting block (21) is arranged in the valve body (1) above the packing pressure ring (20), a valve cover pressure plate (22) is arranged above the plurality of limiting blocks (21), and second bolts (23) are arranged on the valve cover pressure plate (22) and the valve cover (4), and the number of the second bolts (23) and the limiting blocks (21) is a plurality, and the plurality of limiting blocks (21) and the plurality of second bolts (23) are all distributed in a star shape outside the center axis of the valve stem (5).

7. The regulating slide valve for boiler feed water according to claim 1, characterized in that: A guide block (24) is arranged on one end of the valve stem (5) facing the slide plate (3), a guide sleeve (25) is arranged on the outer side of the guide block (24), the bottom end of the guide sleeve (25) is mounted on the top end of the slide plate (3), the bottom of the guide block (24) and the bottom of the inner cavity of the guide sleeve (25) are movably connected, and the bottom of the guide block (24) adopts a curved surface structure.

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