Temperature and pressure reducing valve suitable for multiple working conditions

Abstract

The utility model discloses a temperature and pressure reducing valve suitable for multiple working conditions, belongs to the technical field of valves, and aims at solving the problem that an existing temperature and pressure reducing valve is single in applicable working condition. Comprising a small pressing sleeve, a large valve plug and a fairing which are connected in a sleeved mode from inside to outside, a plurality of first throttling hole sets and a plurality of first communicating holes are formed in the fairing, a plurality of second throttling hole sets and a plurality of third throttling holes are formed in a valve seat, a plurality of fourth throttling hole sets and a plurality of second communicating holes are formed in the large valve plug, and a plurality of fifth throttling hole sets are formed in the small pressing sleeve. The medium inlet, the plurality of first communicating holes, the plurality of second communicating holes, the plurality of fifth throttling hole groups, the plurality of third throttling holes and the medium outlet are communicated in sequence to form a small-load working condition steam passage; the medium inlet, the first throttling hole sets, the second throttling hole sets and the medium outlet are sequentially communicated to form a large-load working condition steam channel, and after the valve is opened, flow adjustment can be conducted on one of the small-load working condition steam channel and the large-load working condition steam channel so as to adapt to different working conditions.

Description

Technical Field

[0001] The utility model belongs to the technical field of valves, and particularly relates to a desuperheating pressure reducing valve applicable to multiple working conditions. Background Technique

[0002] Desuperheating pressure reducing valves are widely used in the regulation of steam pressure and temperature in industries such as thermal power, petrochemical, and metallurgy. The most typical application is the turbine bypass valve, which functions to regulate and divert during turbine startup, shutdown, and load changes, change the steam flow of the turbine, shorten the system adjustment time, and improve the stability of system operation.

[0003] The existing desuperheating pressure reducing valves on the market are usually designed according to parameters such as pressure, temperature, and flow rate under rated working conditions, and have good regulation performance under approximate working conditions. However, under working conditions that deviate greatly from the design parameters, their regulation performance is difficult to meet the requirements, and there are also problems such as large vibration and excessive noise. If operated for a long time, it will also cause damage to the valve itself.

[0004] With the upgrading of the thermal power system and other industries, not only the parameters have been improved, but also flexible load regulation capabilities are required. This puts forward higher requirements for the performance of the desuperheating pressure reducing valve in the system, and it is required to have excellent regulation performance and long-term operation stability under multiple working conditions. Content of the Utility Model

[0005] The purpose of the utility model is to provide a desuperheating pressure reducing valve applicable to multiple working conditions to solve the problem of single applicable working condition of the existing desuperheating pressure reducing valve. The technical solution adopted by the utility model is as follows:

[0006] A desuperheating pressure reducing valve applicable to multiple working conditions includes a valve body, a valve seat, a fairing, a valve cover, a valve rod, a desuperheating component, a large valve plug, and a small bushing;

[0007] The valve body is a three-way structure. The side opening of the valve body is the medium inlet, the lower opening of the valve body is the medium outlet, and the upper opening of the valve body is the control port. The valve body is provided with a valve cavity. A valve seat is provided on the path of the medium outlet. The valve seat is a cup-shaped structure. A plurality of second throttle hole groups are axially opened on the side wall of the valve seat. A plurality of third throttle holes are provided on the bottom wall of the valve seat. The valve cover seals the control port. A fairing is provided between the valve cover and the valve seat. The fairing is a tubular structure. The valve cover seals the upper opening of the fairing. The lower opening of the fairing is connected to the upper opening of the valve seat. A first annular gap cavity is formed between the side wall of the valve cavity and the outer periphery of the fairing. The part of the fairing in the valve cavity is processed with a plurality of first communication holes and a plurality of first throttle hole groups from top to bottom. The plurality of first throttle hole groups are arranged along the axis of the fairing. The medium outlet is connected to the water spraying cylinder body of the desuperheating component;

[0008] The large valve plug includes a first circular tube portion and a second circular tube portion integrally formed up and down. The outer diameter of the first circular tube portion is greater than that of the second circular tube portion. The outer peripheries of the first circular tube portion and the second circular tube portion are connected by a first sealing conical surface. The outer periphery of the first circular tube portion is in sliding fit with the inner periphery of the fairing. A second annular clearance cavity is formed between the area where the fairing is provided with a number of first throttle hole groups and the large valve plug. The outer periphery of the second circular tube portion is in sliding fit with the inner periphery of the valve seat. The top end of the inner wall of the valve seat is provided with a second sealing conical surface. A limiting sleeve and a retaining ring structure are arranged up and down on the inner wall of the first circular tube portion. A small pressure sleeve is arranged between the limiting sleeve and the retaining ring structure. A number of second communication holes are provided on the side wall of the first circular tube portion between the limiting sleeve and the retaining ring structure. A number of fourth throttle hole groups are axially opened on the second circular tube portion;

[0009] The small pressure sleeve is a tubular structure. A third annular clearance cavity is formed between the outer periphery of the small pressure sleeve and the inner periphery of the first circular tube portion. A number of fifth throttle hole groups are axially opened on the small pressure sleeve. The upper end of the valve stem passes through the limiting sleeve and is in sliding and sealing fit with the valve cover. The lower end of the valve stem is provided with a flange valve plug structure. The lower end of the outer periphery of the flange valve plug structure is provided with a third sealing conical surface. The upper end of the inner periphery of the retaining ring structure is provided with a fourth sealing conical surface. The outer periphery of the flange valve plug structure is in sliding fit with the inner periphery of the small pressure sleeve;

[0010] When the valve is fully closed, the first sealing conical surface and the second sealing conical surface are in sealing fit. The side wall of the valve seat closes a number of fourth throttle hole groups. The side wall of the second circular tube portion closes a number of second throttle hole groups. A number of first communication holes and a number of second communication holes are aligned and communicated one by one. The third sealing conical surface and the fourth sealing conical surface are in sealing fit. The flange valve plug structure closes a number of fifth throttle hole groups;

[0011] When the valve stem slides upward and the third sealing conical surface and the fourth sealing conical surface are separated, when a number of fifth throttle hole groups are completely unblocked or partially unblocked, the medium inlet, the first annular clearance cavity, a number of first communication holes, a number of second communication holes, the third annular clearance cavity, a number of fifth throttle hole groups, the inner cavity of the small pressure sleeve, the lower opening of the large valve plug, a number of third throttle holes and the medium outlet are sequentially communicated to form a steam passage under small load conditions;

[0012] When the valve stem continues to slide upward and the first sealing conical surface and the second sealing conical surface are separated, when a number of second communication hole groups are completely unblocked or partially unblocked, a number of fourth throttle hole groups are also completely unblocked or partially unblocked. A number of first communication holes and a number of second communication holes are misaligned. The medium inlet, the first annular clearance cavity, a number of first throttle hole groups, the second annular clearance cavity, the lower opening of the large valve plug, a number of second throttle hole groups or a number of third throttle holes, and the medium outlet are sequentially communicated to form a steam passage under large load conditions.

[0013] Further, the valve cover is provided with an inner hole, and a stuffing box is machined on the upper end surface of the valve cover. The stuffing box is connected to the upper end of the inner hole. A stuffing assembly is arranged in the stuffing box, and a stuffing gland presses the stuffing assembly against the bottom surface of the stuffing box. The valve stem passes through the inner hole, the stuffing box and the stuffing gland, and the valve stem and the valve cover are in sliding seal fit through the stuffing assembly.

[0014] Further, a sunk groove is machined on the lower end surface of the valve cover. The sunk groove is connected to the lower end of the inner hole of the valve cover. A guide sleeve is arranged in the sunk groove, and the valve stem is in sliding fit with the guide sleeve.

[0015] Further, the outer periphery of the upper part of the fairing is in fit with the inner wall of the control port, and the lower end of the fairing is in fit with the stop of the valve seat.

[0016] Further, a connecting ring structure is arranged on the inner wall of the large valve plug. The outer periphery of the limit sleeve is in threaded fit with the inner periphery of the connecting ring structure.

[0017] Further, the limit sleeve is provided with a pressure balance hole that penetrates up and down.

[0018] Further, the upper end surface of the small gland abuts against the lower end surface of the limit sleeve. A sunk platform is arranged on the upper end surface of the retaining ring structure, and the lower end of the small gland is in fit with the stop of the sunk platform of the retaining ring structure.

[0019] Further, a set of disc springs is sleeved on the valve stem. The compression nut is in threaded connection with the valve stem, and the compression nut and the valve stem are connected and locked by a pin shaft. The compression nut, the set of disc springs and the limit sleeve abut against each other in sequence from top to bottom.

[0020] Further, the top end of the first circular tube part is connected to the sealing gland. A valve plug sealing ring is arranged between the first circular tube part and the sealing gland. The first circular tube part is in sliding seal fit with the inner periphery of the fairing through the valve plug sealing ring.

[0021] Further, the desuperheating assembly further includes a spring nozzle, a water collecting chamber, a water spraying connecting pipe, a connecting seat and a connecting flange. The upper end of the water spraying cylinder is connected to the medium outlet. The water spraying connecting pipe is arranged on one side of the water spraying cylinder. The connecting seat is hermetically connected to the water spraying connecting pipe. The connecting flange, the connecting seat and the water collecting chamber are connected in sequence. The water collecting chamber extends into the water spraying cylinder, and a plurality of spring nozzles are arranged axially on the lower side of the water collecting chamber.

[0022] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0023] The utility model has two different throttling and pressure-reducing passages, namely a steam passage under small-load condition and a steam passage under large-load condition, and has different flow characteristics at different opening degrees of the desuperheating and pressure-reducing valve. When the valve stem is lifted in the fully closed valve state, first the steam passage under small-load condition is opened, and the steam passage under large-load condition is still in the closed state. By adjusting the relative position of the flange valve plug structure and the small bushing, the number of unobstructed fifth throttle hole groups is adjusted. At this time, the flow coefficient of the desuperheating and pressure-reducing valve is small, which is suitable for small-load conditions and can be finely adjusted. When the flange valve plug structure abuts against the limit sleeve, when the valve stem is continuously lifted, the valve stem can drive the large valve plug to slide upward, and then a plurality of first communication holes and a plurality of second communication holes are misaligned, the steam passage under small-load condition is closed, the first sealing cone surface and the second sealing cone surface are separated, and the steam passage under large-load condition is opened. At this time, the flow coefficient of the desuperheating and pressure-reducing valve is large, which is suitable for working conditions with larger loads. The resistance of the desuperheating and pressure-reducing valve is small, ensuring that enough steam can pass through. During operation, by adjusting the opening degree of the desuperheating and pressure-reducing valve, continuous control of the steam pressure and flow can be achieved, meeting the operation requirements of special working conditions such as the start-up, shutdown and large-range adjustment of the steam system, ensuring the stability of the steam supply quantity and steam supply parameters, and ensuring the safety of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic structural diagram of the utility model in the fully closed valve state;

[0025] Figure 2 is a schematic structural diagram of the valve body;

[0026] Figure 3 is a schematic structural diagram of the fairing;

[0027] Figure 4 is a schematic structural diagram of the valve seat;

[0028] Figure 5 is a schematic structural diagram of the cooperation of the large valve plug, the small bushing and the valve stem;

[0029] Figure 6 is a partial schematic diagram of the valve stem;

[0030] Figure 7 is a schematic structural diagram of the large valve plug;

[0031] Figure 8 is a schematic structural diagram of the small bushing;

[0032] Figure 9 is a schematic structural diagram of the valve cover;

[0033] Figure 10 is a schematic structural diagram of the desuperheating component;

[0034] Figure 11It is a schematic diagram of the state where the steam passage of the utility model is fully opened under light load conditions;

[0035] Figure 12 It is a schematic diagram of the state where the steam passage of the utility model is fully opened under heavy load conditions.

[0036] In the figure, 1. Valve body, 11. Medium inlet, 12. Valve cavity, 13. Medium outlet, 14. Control port, 15. First annular clearance cavity, 2. Valve seat, 21. Second throttle hole group, 22. Third throttle hole, 23. Second sealing cone surface, 3. Rectifying cover, 31. First communication hole, 32. First throttle hole group, 33. Second annular clearance cavity, 4. Valve cover, 41. Guide sleeve, 42. Packing assembly, 43. Packing gland, 44. Stuffing box, 45. Inner hole, 46. Groove, 5. Valve stem, 51. Compression nut, 52. Pin shaft, 53. Disc spring group, 54. Flange valve plug structure, 55. Third sealing cone surface, 6. Large valve plug, 61. Sealing gland, 62. Valve plug sealing ring, 63. Limit sleeve, 64. Pressure balance hole, 65. Connecting ring structure, 66. First round tube part, 67. First communication hole, 68. Retaining ring structure, 69. First sealing cone surface, 610. Fourth throttle hole group, 611. Second round tube part, 612. Fourth sealing cone surface, 613. Third annular clearance cavity, 7. Small bushing, 71. Fifth throttle hole group, 8. Desuperheating assembly, 81. Water spraying cylinder body, 82. Spring nozzle, 83. Water collecting cavity, 84. Water spraying connecting pipe, 85. Connecting seat, 86. Connecting flange. Detailed implementation manners

[0037] To make the objectives, technical solutions and advantages of the utility model more clear and understandable, the utility model will be described below through specific embodiments shown in the drawings. However, it should be understood that these descriptions are only exemplary and are not intended to limit the scope of the utility model. In addition, in the following description, the descriptions of well-known structures and technologies are omitted to avoid unnecessarily confusing the concepts of the utility model.

[0038] The connections mentioned in the utility model are divided into fixed connections and detachable connections. The fixed connection is an inseparable connection including but not limited to conventional fixed connection methods such as hemming connection, rivet connection, bonding connection and welding connection. The detachable connection includes but not limited to conventional disassembly methods such as bolt connection, snap connection, pin connection and hinge connection. When the specific connection method is not clearly defined, it is default that at least one connection method can be found among the existing connection methods to achieve this function, and those skilled in the art can select according to their needs. For example: welding connection is selected for fixed connection, and bolt connection is selected for detachable connection.

[0039] The following will further elaborate on the utility model in conjunction with the drawings. The following embodiments are explanations of the utility model, and the utility model is not limited to the following embodiments.

[0040] Embodiment: As Figures 1 to 12 shown, a desuperheating pressure reducing valve applicable to multiple working conditions includes a valve body 1, a valve seat 2, a fairing 3, a valve cover 4, a valve stem 5, a desuperheating assembly 8, a large valve plug 6 and a small bushing 7;

[0041] The valve body 1 is a three-way structure. The side opening of the valve body 1 is a medium inlet 11, the lower opening of the valve body 1 is a medium outlet 13, and the upper opening of the valve body 1 is a control port 14. The valve body 1 is provided with a valve cavity 12. The control port 14, the medium inlet 11 and the medium outlet 13 are communicated through the valve cavity 12. A valve seat 2 is provided on the path diameter of the medium outlet 13. The valve seat 2 is a cup-shaped structure. A number of second throttle hole groups 21 are axially formed on the side wall of the valve seat 2. Each group of second throttle hole groups 21 is composed of a number of small holes evenly arranged in a circle on the side wall of the valve seat 2. A number of third throttle holes 22 are provided on the bottom wall of the valve seat 2. The number of second throttle hole groups 21 and the number of third throttle holes 22 are used for throttling and pressure reduction of steam. The valve cover 4 is connected to the valve body 1 through a fastener. The valve cover 4 seals the control port 14. A fairing 3 is provided between the valve cover 4 and the valve seat 2. The fairing 3 is a tubular structure. The valve cover 4 seals the upper opening of the fairing 3. The lower opening of the fairing 3 is connected to the upper opening of the valve seat 2. A first annular gap cavity 15 is formed between the side wall of the valve cavity 12 and the outer periphery of the fairing 3. A number of first communication holes 31 and a number of first throttle hole groups 32 are machined from top to bottom on the part of the fairing 3 located in the valve cavity 12. The number of first throttle hole groups 32 is arranged along the axis of the fairing 3. The medium outlet 13 is connected to the water spraying cylinder body 81 of the desuperheating assembly 8. Each group of first throttle hole groups 32 is composed of a number of small holes evenly arranged in a circle on the side wall of the fairing 3, and is used to make the steam in the flow channel evenly distributed;

[0042] The large valve plug 6 includes a first circular tube portion 66 and a second circular tube portion 611 integrally formed up and down. The outer diameter of the first circular tube portion 66 is greater than that of the second circular tube portion 611. The outer peripheries of the first circular tube portion 66 and the second circular tube portion 611 are connected by a first sealing conical surface 69. The outer periphery of the first circular tube portion 66 is in sliding fit with the inner periphery of the fairing 3. An annular groove is machined on the inner wall of the fairing 3 in the area where a number of first throttle hole groups 32 are provided. A second annular clearance cavity 33 is formed between the area of the fairing 3 where a number of first throttle hole groups 32 are provided and the large valve plug 6. The outer periphery of the second circular tube portion 611 is in sliding fit with the inner periphery of the valve seat 2. The top end of the inner wall of the valve seat 2 is provided with a second sealing conical surface 23. A limit sleeve 63 and a retaining ring structure 68 are arranged up and down on the inner wall of the first circular tube portion 66. A small pressure sleeve 7 is arranged between the limit sleeve 63 and the retaining ring structure 68. A number of second communication holes 67 are provided on the side wall of the first circular tube portion 66 between the limit sleeve 63 and the retaining ring structure 68. A number of fourth throttle hole groups 610 are axially formed on the second circular tube portion 611. Each group of fourth throttle hole groups 610 is composed of a number of small holes evenly arranged in a circumferential direction on the side wall of the large valve plug 6. A number of fourth throttle hole groups 610 are located below the retaining ring structure 68;

[0043] The small pressure sleeve 7 is of a tubular structure. A third annular clearance cavity 613 is formed between the outer periphery of the small pressure sleeve 7 and the inner periphery of the first circular tube portion 66. A number of fifth throttle hole groups 71 are axially formed on the small pressure sleeve 7. Each group of fifth throttle hole groups 71 is composed of a number of small holes evenly arranged in a circumferential direction on the side wall of the small pressure sleeve 7. The upper end of the valve stem 5 passes through the limit sleeve 63 and is in sliding and sealing fit with the valve cover 4. The lower end of the valve stem 5 is provided with a flange valve plug structure 54. The lower end of the outer periphery of the flange valve plug structure 54 is provided with a third sealing conical surface 55. The upper end of the inner periphery of the retaining ring structure 68 is provided with a fourth sealing conical surface 612. The outer periphery of the flange valve plug structure 54 is in sliding fit with the inner periphery of the small pressure sleeve 7. The flange valve plug structure 54 is used to adjust the closed number of a number of fifth throttle hole groups 71;

[0044] When the valve is fully closed, the first sealing conical surface 69 and the second sealing conical surface 23 are in sealing fit. The side wall of the valve seat 2 closes a number of fourth throttle hole groups 610. The side wall of the second circular tube portion 611 closes a number of second throttle hole groups 21. A number of first communication holes 31 are in one-to-one alignment and communication with a number of second communication holes 67. The third sealing conical surface 55 and the fourth sealing conical surface 612 are in sealing fit. The flange valve plug structure 54 closes a number of fifth throttle hole groups 71;

[0045] When the valve stem 5 slides upward from the fully closed valve state and the third sealing conical surface 55 separates from the fourth sealing conical surface 612, and when several fifth throttle hole groups 71 are completely unobstructed or partially unobstructed, the medium inlet 11, the first annular clearance cavity 15, several first communication holes 31, several second communication holes 67, the third annular clearance cavity 613, several fifth throttle hole groups 71, the inner cavity of the small packing sleeve 7, the lower opening of the large valve plug 6, several third throttle holes 22, and the medium outlet 13 are connected in sequence to form a steam passage under small load conditions;

[0046] When the valve stem 5 continues to slide upward and the first sealing conical surface 69 separates from the second sealing conical surface 23, and when several second communication hole groups 67 are completely unobstructed or partially unobstructed, several fourth throttle hole groups 610 are also completely unobstructed or partially unobstructed, and several first communication holes 31 are misaligned with several second communication holes 67, the medium inlet 11, the first annular clearance cavity 15, several first throttle hole groups 32, the second annular clearance cavity 33, the lower opening of the large valve plug 6, several second throttle hole groups 21 or several third throttle holes 22, and the medium outlet 13 are connected in sequence to form a steam passage under large load conditions.

[0047] The utility model has two different throttle and pressure reduction passages, namely a steam passage under small load conditions and a steam passage under large load conditions, and has different flow characteristics at different opening degrees of the temperature-reducing and pressure-reducing valve. When the valve stem 5 is lifted upward in the fully closed valve state, first, the steam passage under small load conditions is opened, and the steam passage under large load conditions is still in the closed state. By adjusting the relative position of the flange valve plug structure 54 and the small packing sleeve 7, the unobstructed number of several fifth throttle hole groups 71 is adjusted. At this time, the flow coefficient of the temperature-reducing and pressure-reducing valve is small, which is suitable for small load conditions and can be finely adjusted; when the flange valve plug structure 54 abuts against the limit sleeve 63, the valve stem 4 is continuously lifted upward, and the valve stem 5 can drive the large valve plug 6 to slide upward. Furthermore, several first communication holes 31 are misaligned with several second communication holes 67, the steam passage under small load conditions is closed, the first sealing conical surface 69 separates from the second sealing conical surface 23, and the steam passage under large load conditions is opened. At this time, the flow coefficient of the temperature-reducing and pressure-reducing valve is large, which is suitable for working conditions with larger loads. The resistance of the temperature-reducing and pressure-reducing valve is small, ensuring that sufficient steam can pass through. During operation, by adjusting the opening degree of the temperature-reducing and pressure-reducing valve, continuous control of the steam pressure and flow can be achieved, meeting the operating requirements of special working conditions such as the start-up, shutdown, and large-range adjustment of the steam system, ensuring the stability of the steam supply volume and supply parameters, and ensuring the safety of the system.

[0048] The valve cover 4 is provided with an inner hole 45. A stuffing box 44 is machined on the upper end surface of the valve cover 4. The stuffing box 44 is connected to the upper end of the inner hole 45. A packing assembly 42 is arranged in the stuffing box 44. The packing gland 43 presses the packing assembly 42 against the bottom surface of the stuffing box 44. The valve stem 5 passes through the inner hole 45, the stuffing box 44, and the packing gland 43. The valve stem 5 and the valve cover 4 are in sliding sealing fit through the packing assembly 42.

[0049] A counterbore 46 is machined on the lower end face of the valve cover 4. The counterbore 46 is connected to the lower end of the inner hole 45 of the valve cover 4. A guide sleeve 41 is provided in the counterbore 46. The valve stem 5 is slidably engaged with the guide sleeve 41. The guide sleeve 41 is installed between the valve cover 4 and the valve stem 5 to guide and position the movement of the valve stem 5.

[0050] The outer periphery of the upper part of the fairing 3 is fitted with the inner wall of the control port 14, and the lower end of the fairing 3 is fitted with the spigot of the valve seat 2.

[0051] A connecting ring structure 65 is provided on the inner wall of the large valve plug 6. The outer periphery of the limit sleeve 63 is threadedly engaged with the inner periphery of the connecting ring structure 65.

[0052] The limit sleeve 63 is provided with a pressure balance hole 64 that penetrates up and down.

[0053] The upper end face of the small pressure sleeve 7 abuts against the lower end face of the limit sleeve 63. A counterbore is provided on the upper end face of the retaining ring structure 68, and the lower end of the small pressure sleeve 7 is fitted with the spigot of the counterbore of the retaining ring structure 68.

[0054] A disc spring group 53 is sleeved on the valve stem 5. The compression nut 51 is threadedly connected to the valve stem 5, and the compression nut 51 and the valve stem 5 are connected and locked by a pin shaft 52. The compression nut 51, the disc spring group 53 and the limit sleeve 63 abut against each other in sequence from top to bottom. The disc spring group 53 is composed of a number of disc springs stacked together. The concave surface of the lowermost disc spring faces the limit sleeve 63. Each two disc springs are stacked in the way that the concave surface faces the concave surface and the convex surface faces the convex surface. The top is fixed by the compression nut 51. The compression nut 51 is threadedly connected to the valve stem 5 and fixed by a stop pin.

[0055] The top end of the first circular tube portion 66 is connected to the sealing gland 61. A valve plug sealing ring 62 is provided between the first circular tube portion 66 and the sealing gland 61. The first circular tube portion 66 is slidably and sealingly fitted with the inner periphery of the fairing 3 through the valve plug sealing ring 62.

[0056] The desuperheating assembly 8 further includes a spring nozzle 82, a water collecting chamber 83, a water spraying connecting pipe 84, a connecting seat 85 and a connecting flange 86. The upper end of the water spraying cylinder body 81 is connected to the medium outlet 13. The water spraying connecting pipe 84 is arranged on one side of the water spraying cylinder body 81. The connecting seat 85 is sealingly connected to the water spraying connecting pipe 84. The connecting flange 86, the connecting seat 85 and the water collecting chamber 83 are connected in sequence. The water collecting chamber 83 extends into the water spraying cylinder body 81. A number of spring nozzles 82 are axially arranged on the lower side of the water collecting chamber 83. The spring nozzles 82 in the desuperheating assembly 8 can be selected from different models, and their opening pressures and flow rates can be combined and set according to different working conditions.

[0057] The above embodiments are only illustrative descriptions of the present utility model and do not limit its protection scope. Those skilled in the art can also make partial changes to it, as long as they do not exceed the spiritual essence of the present utility model, they are within the protection scope of the present utility model.

Claims

1. A temperature and pressure reducing valve suitable for multiple working conditions, characterized in that: It comprises a valve body (1), a valve seat (2), a fairing (3), a valve cover (4), a valve stem (5), a temperature reduction component (8), a large valve plug (6) and a small compression sleeve (7); The valve body (1) is a three-way structure, the side opening of the valve body (1) is a medium inlet (11), the lower opening of the valve body (1) is a medium outlet (13), the upper opening of the valve body (1) is a control port (14), the valve body (1) is provided with a valve cavity (12), a valve seat (2) is provided on the path of the medium outlet (13), the valve seat (2) is a cup-shaped structure, a plurality of second throttling hole groups (21) are provided on the side wall of the valve seat (2) along the axial direction, a plurality of third throttling holes (22) are provided on the bottom wall of the valve seat (2), the valve cover (4) seals the control port (14), and a rectifying member (24) is provided between the valve cover (4) and the valve seat (2) A hood (3), the fairing (3) is a tubular structure, the valve cover (4) seals the upper end opening of the fairing (3), the lower end opening of the fairing (3) is connected to the upper opening of the valve seat (2), a first annular gap cavity (15) is formed between the side wall of the valve cavity (12) and the outer periphery of the fairing (3), a portion of the fairing (3) in the valve cavity (12) is processed with a plurality of first connecting holes (31) and a plurality of first throttling hole groups (32) from top to bottom, the plurality of first throttling hole groups (32) are arranged along the axial direction of the fairing (3), and the medium outlet (13) is connected to a water spray cylinder (81) of a temperature reduction component (8); The large valve plug (6) comprises a first circular tube portion (66) and a second circular tube portion (611) which are integrally formed from top to bottom. The outer diameter of the first circular tube portion (66) is larger than the outer diameter of the second circular tube portion (611). The outer peripheries of the first circular tube portion (66) and the second circular tube portion (611) are connected via a first sealing cone surface (69). The outer periphery of the first circular tube portion (66) is slidably matched with the inner periphery of the fairing (3). A second annular gap cavity (33) is formed between the region where the fairing (3) is provided with a plurality of first throttling hole groups (32) and the large valve plug (6). The second circular tube portion (6 The outer periphery of the valve seat (11) is slidably matched with the inner periphery of the valve seat (2), the top of the inner wall of the valve seat (2) is provided with a second sealing cone surface (23), a limit sleeve (63) and a retaining ring structure (68) are provided on the inner wall of the first circular tube portion (66) from top to bottom, a small pressure sleeve (7) is provided between the limit sleeve (63) and the retaining ring structure (68), a plurality of second connecting holes (67) are provided on the side wall of the first circular tube portion (66) located between the limit sleeve (63) and the retaining ring structure (68), and a plurality of fourth throttling hole groups (610) are opened in the axial direction on the second circular tube portion (611); The small pressure sleeve (7) is a tubular structure, and a third annular gap cavity (613) is formed between the outer periphery of the small pressure sleeve (7) and the inner periphery of the first circular tube portion (66). A plurality of fifth throttle hole groups (71) are axially opened on the small pressure sleeve (7). The upper end of the valve stem (5) passes through the limit sleeve (63) and is slidably sealed with the valve cover (4). The lower end of the valve stem (5) is provided with a flange valve plug structure (54), and the outer periphery lower end of the flange valve plug structure (54) is provided with a third sealing cone surface (55). The inner periphery upper end of the retaining ring structure (68) is provided with a fourth sealing cone surface (612), and the outer periphery of the flange valve plug structure (54) is slidably matched with the inner periphery of the small pressure sleeve (7). When the valve is completely closed, the first sealing cone surface (69) and the second sealing cone surface (23) are in sealing cooperation, the side wall of the valve seat (2) closes a plurality of fourth throttling hole groups (610), the side wall of the second circular tube portion (611) closes a plurality of second throttling hole groups (21), a plurality of first communicating holes (31) are in one-to-one communication with a plurality of second communicating holes (67), the third sealing cone surface (55) and the fourth sealing cone surface (612) are in sealing cooperation, and the flange valve plug structure (54) closes a plurality of fifth throttling hole groups (71); When the valve stem (5) slides upward, the third sealing cone surface (55) is separated from the fourth sealing cone surface (612), and the plurality of fifth throttling hole groups (71) are completely or partially unblocked, the medium inlet (11), the first annular gap cavity (15), the plurality of first communicating holes (31), the plurality of second communicating holes (67), the third annular gap cavity (613), the plurality of fifth throttling hole groups (71), the inner cavity of the small pressure sleeve (7), the lower opening of the large valve plug (6), the plurality of third throttling holes (22) and the medium outlet (13) are connected in sequence to form a steam passage under a small load condition; The valve stem (5) continues to slide upward, the first sealing cone surface (69) and the second sealing cone surface (23) are separated, and when the plurality of second connecting holes (67) groups are completely or partially unblocked, the plurality of fourth throttling hole groups (610) are also completely or partially unblocked, the plurality of first connecting holes (31) and the plurality of second connecting holes (67) are misaligned, and the medium inlet (11), the first annular gap cavity (15), the plurality of first throttling hole groups (32), the second annular gap cavity (33), the lower opening of the large valve plug (6), the plurality of second throttling hole groups (21) or the plurality of third throttling holes (22), and the medium outlet (13) are connected in sequence to form a steam passage under high load conditions.

2. A temperature and pressure reducing valve suitable for multiple working conditions according to claim 1, characterized in that: The valve cover (4) is provided with an inner hole (45), and a stuffing box (44) is processed on the upper end surface of the valve cover (4). The stuffing box (44) is connected to the upper end of the inner hole (45). A stuffing assembly (42) is provided in the stuffing box (44). A stuffing gland (43) presses the stuffing assembly (42) on the bottom surface of the stuffing box (44). The valve stem (5) passes through the inner hole (45), the stuffing box (44) and the stuffing gland (43). The valve stem (5) and the valve cover (4) are slidably sealed through the stuffing assembly (42).

3. A temperature and pressure reducing valve suitable for multiple working conditions according to claim 2, characterized in that: A recessed groove (46) is machined on the lower end surface of the valve cover (4), the recessed groove (46) is connected to the lower end of the inner hole (45) of the valve cover (4), a guide sleeve (41) is arranged in the recessed groove (46), and the valve stem (5) and the guide sleeve (41) are slidably matched.

4. The temperature and pressure reducing valve applicable to multiple working conditions according to claim 1, characterized in that: The upper outer periphery of the fairing (3) matches with the inner wall of the control port (14), and the lower end of the fairing (3) matches with the stopper of the valve seat (2).

5. The temperature and pressure reducing valve applicable to multiple working conditions according to claim 1, characterized in that: A connecting ring structure (65) is provided on the inner wall of the large valve plug (6); the outer periphery of the limiting sleeve (63) is threadably connected to the inner periphery of the connecting ring structure (65).

6. The temperature and pressure reducing valve applicable to multiple working conditions according to claim 1, characterized in that: The limiting sleeve (63) is provided with a pressure balance hole (64) which is transparent from top to bottom.

7. The temperature and pressure reducing valve applicable to multiple working conditions according to claim 1, characterized in that: The upper end surface of the small pressing sleeve (7) abuts against the lower end surface of the limiting sleeve (63), a sinking platform is provided on the upper end surface of the retaining ring structure (68), and the lower end of the small pressing sleeve (7) cooperates with the stopper of the sinking platform of the retaining ring structure (68).

8. The temperature and pressure reducing valve applicable to multiple working conditions according to claim 1, characterized in that: A disc spring assembly (53) is sleeved on the valve stem (5), a clamping nut (51) is threadedly connected to the valve stem (5), the clamping nut (51) and the valve stem (5) are connected and stopped via a pin shaft (52), and the clamping nut (51), the disc spring assembly (53) and the limiting sleeve (63) are abutted against each other in sequence from top to bottom.

9. The temperature and pressure reducing valve applicable to multiple working conditions according to claim 1, characterized in that: The top end of the first circular tube portion (66) is connected to the sealing gland (61), a valve plug sealing ring (62) is provided between the first circular tube portion (66) and the sealing gland (61), and the first circular tube portion (66) is slidably sealed with the inner circumference of the fairing (3) via the valve plug sealing ring (62).

10. A temperature and pressure reducing valve suitable for multiple working conditions according to any one of claims 1 to 9, characterized in that: The cooling assembly (8) further comprises a spring nozzle (82), a water collecting chamber (83), a water spray pipe (84), a connecting seat (85) and a connecting flange (86); the upper end of the water spray cylinder (81) is connected to the medium outlet (13); the water spray pipe (84) is arranged on one side of the water spray cylinder (81); the connecting seat (85) is sealedly connected to the water spray pipe (84); the connecting flange (86), the connecting seat (85) and the water collecting chamber (83) are connected in sequence; the water collecting chamber (83) extends into the water spray cylinder (81); and a plurality of spring nozzles (82) are axially arranged on the lower side of the water collecting chamber (83).

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