A high performance pilot spring diaphragm pressure reducing valve

Abstract

The present invention relates to a high-performance pilot spring diaphragm pressure reducing valve, including main parts such as a core-filling joint, a compression spring, a filter, a pilot pressure reducing valve and a main pressure reducing valve. A filter is provided at the medium inlet of the valve body, and outwards are a compression spring and a core-filling joint in sequence. The center is the main pressure reducing valve, and the side is the pilot pressure reducing valve. The main feature is that in the closed cavity formed by the valve cover and the valve body, the controlled medium enters the pilot pressure reducing valve from the pilot hole of the valve body, and after pressure reduction, the medium enters the upper cavity of the main diaphragm of the main pressure reducing valve from the control hole of the valve body, the main valve stem opens, the medium flows to the outlet, and the pressure is fed back to the pilot pressure reducing valve from the feedback hole of the valve body. The forces in the pilot pressure reducing valve and the main pressure reducing valve are quickly balanced again, and the medium is stably reduced to the set pressure. The valve organically combines the pilot pressure reducing valve and the main pressure reducing valve, has a compact structure, gives full play to the characteristics of fast response and sensitive adjustment of the pilot pressure reducing valve and the spring diaphragm pressure reducing valve, has stable pressure regulation, and has the remarkable advantages of durability and a wide range of use.

Description

Technical Field

[0001] The invention belongs to the technical field of valves, and in particular relates to a high-performance pilot spring diaphragm pressure reducing valve which is shock-resistant and dirt-resistant, has a compact structure, stable pressure regulation, and a large flow rate. Background Art

[0002] The regulating valve is a throttling element with variable local resistance, that is, by changing the throttling area, the flow rate and kinetic energy of the fluid are changed, resulting in different pressure losses, thereby achieving the purpose of pressure regulation. The existing regulating valves generally have the following problems:

[0003] 1. When the process requires a higher medium input pressure, a pressure regulating spring with a large stiffness is generally selected. When the flow pressure changes, the output pressure fluctuates greatly. In order to reduce pressure fluctuations, the valve diameter is reduced and the spring stiffness is reduced, but the flow restriction is serious.

[0004] 2. When the process requires a large flow rate of medium output, the valve structure is large and occupies too much installation space.

[0005] 3. When the upstream pressure of the medium fluctuates greatly, firstly, the moving parts vibrate severely, the valve stem and sealing surface are easily worn, and the service life of the valve is short; secondly, the outlet pressure fluctuates greatly and the pressure regulation is unstable.

[0006] 4. The valve has no safety protection, and the valve core and other moving parts are easily stuck by impurities, damaging the valve itself or even the equipment.

[0007] The flame cleaning machine, cutting machine, ingot corner cleaning machine and other equipment in the metallurgical industry require the regulating valve to be compact and small to meet their installation requirements, suitable for a wide range of pressure regulation, large flow, large pressure drop, stable pressure regulation, dirt resistance and shock resistance, and long service life. Therefore, it is particularly important to develop a high-performance pilot spring diaphragm pressure reducing valve that is shock-resistant, dirt-resistant, compact, stable pressure regulation, and has a large flow rate. Summary of the invention

[0008] The invention aims to provide a high-performance pilot spring film pressure reducing valve which is shock-resistant, dirt-resistant, compact in structure, stable in pressure regulation and has a large flow rate.

[0009] A high-performance pilot spring diaphragm pressure reducing valve proposed in the present invention comprises a valve body 1, a core-buffering joint 2, a compression spring 3, a filter screen 4, a pilot pressure reducing valve and a main pressure reducing valve; the pilot pressure reducing valve is located at one side of the valve body 1, and the main pressure reducing valve is located at the center of the valve body 1; a filter screen 4 is provided at the medium inlet of the valve body 1, a compression spring 3 is provided above the filter screen 4, and the medium inlet of the valve body 1 is connected to the core-buffering joint 2; the main pressure reducing valve and the pilot pressure reducing valve are communicated through the pilot hole 39, the control hole 36 and the feedback hole 38 of the valve body 1, and the control hole 36 on the valve body 1 is communicated with the main valve cover 11 through the control conduit 35; the process hole of the pilot hole 39 of the valve body 1 is provided with a plug 40 to prevent the upper and lower chambers from communicating, and a pressure gauge 41 is provided at the outer end of the process hole to detect the output pressure;

[0010] The main pressure reducing valve is a spring diaphragm type pressure reducing valve, which is composed of a main nozzle 5, a main valve stem 6, a main pressure regulating spring 7, a main end cover 9, a first O-ring 10, a main valve cover 11, a main diaphragm assembly, a limit plate 17 and a second O-ring 18. The main nozzle 5 extends into one end of the valve body 1, the valve body 1 and the main end cover 9 are connected through the first O-ring 10, and the main pressure regulating spring 7 is provided on the concave platform of the main end cover 9; a main valve stem 6 is provided between the main pressure regulating spring 7 and the main nozzle 5; a second O-ring 18 is provided between the limit plate 17 and the valve body 1, A main diaphragm assembly is arranged above the limit plate 17, and the main diaphragm assembly is composed of a first diaphragm pressure plate 13, a second diaphragm pressure plate 15 and a main diaphragm 16. The first diaphragm pressure plate 13 and the second diaphragm pressure plate 15 are arranged on the left and right sides of the main diaphragm 16, and the first diaphragm pressure plate 13, the second diaphragm pressure plate 15 and the main diaphragm 16 are fixed by a main locking nut 14; the edge of the main diaphragm assembly fits the main valve cover 11, and the main valve cover 11 is fixed to the valve body 1 by hexagonal bolts, thereby ensuring good sealing of the valve;

[0011] The pilot pressure reducing valve is a spring diaphragm type pressure reducing valve, which is composed of a pilot end cover 19, a third O-ring 20, a valve core 23, a pilot nozzle 24, a pilot valve stem 25, a pilot pressure regulating spring 29, a T-handwheel 30, a pilot pressure bearing spring 31, a pilot valve cover 33 and a pilot diaphragm assembly. The pilot diaphragm assembly is composed of a locking bolt 26, a pilot diaphragm 27 and a pilot locking nut 28. A third O-ring 20 is provided at the threaded recess of the valve body 1 and the pilot end cover 19 to ensure the sealing of the pilot pressure reducing valve; the pilot end cover 19 is provided with a pilot concave platform in the center. A pressure-bearing spring 31, one end of the valve core 23 is inserted into the pilot pressure-bearing spring 31, and the other end is sleeved on the pilot valve stem 25, and the end of the valve core 23 is connected to the pilot nozzle 24; the pilot valve stem 25 passes through the valve body 1 and is pressed against the pilot diaphragm assembly, a flat gasket 34 is provided between the pilot diaphragm assembly and the pilot valve cover 33, the pilot valve cover 33 is threadedly connected to the valve body 1, a pilot pressure-regulating spring 29 is provided under the pilot diaphragm assembly, a spring cover plate 32 is provided at the connection between the pilot pressure-regulating spring 29 and the pilot valve cover 33, and one end of the T-shaped handwheel 30 is pressed against the spring cover plate 32.

[0012] In the present invention, a fourth O-ring 42 is disposed between the valve body 1 and the control conduit 35 .

[0013] In the present invention, a screen 37 is provided on the pressure taking hole on the valve body 1 .

[0014] In the present invention, the damper sleeve 8 is nested in the center of the main end cover 9 .

[0015] In the present invention, the tail of the nozzle 5 is nested in the guide sleeve 22 .

[0016] In the present invention, the pilot valve stem 25 is a bow-shaped structure.

[0017] In the present invention, the main valve cover 11 is provided with a control hole 36 .

[0018] In the present invention, both the pilot pressure reducing valve and the main pressure reducing valve are diaphragm pressure reducing valves, which give full play to their structural characteristics of high sensitivity and good pressure resistance. The two diaphragm pressure reducing valves are combined into a pilot spring diaphragm pressure reducing valve. The medium enters the pilot pressure reducing valve from the pilot hole on the valve body 1, and the T-shaped hand wheel 30 is rotated clockwise to compress the pilot pressure regulating spring 29, drive the pilot valve stem 25, and adjust the gap between the valve core 23 and the pilot nozzle 24. After the medium is quickly decompressed, it enters the main pressure reducing valve from the control hole of the valve body 1, drives the main diaphragm assembly, and pushes open the main valve stem 6. The medium is decompressed and enters the downstream. The medium pressure is fed back to the pilot pressure reducing valve from the feedback hole on the outlet side of the valve body 1 to participate in the force balance process, and the pressure is quickly reduced to the set pressure. When the pressure at the front end of the medium fluctuates, the force balance between the pilot pressure reducing valve and the main pressure reducing valve is broken. If the outlet pressure is higher than the set pressure, the pressure is quickly fed back to the pilot pressure reducing valve, giving full play to the high sensitivity of the diaphragm. The diaphragm and spring respond quickly, reducing the opening of the pilot pressure reducing valve and the opening of the main pressure reducing valve. The forces of the pilot pressure reducing valve and the main pressure reducing valve are quickly balanced again, and vice versa. In this way, the pressure is always stable within a small deviation from the set pressure. This automatic feedback adjustment of pressure gives full play to the fast response and sensitive adjustment characteristics of the pilot spring diaphragm pressure reducing valve, effectively weakens pressure fluctuations, and maintains the stability of the output pressure. Because this structure can fully utilize the medium's own pressure to participate in the internal force balance process of the valve, the valve is designed with a large diameter, and the flow rate is also large at the same pressure.

[0019] The beneficial effects of the present invention are as follows: the present invention organically combines the pilot pressure reducing valve and the main pressure reducing valve, and has a compact structure. A filter screen 4 is provided at the medium inlet, which can effectively prevent impurities from entering the valve interior to prevent them from clogging the channel, jamming the valve stem, and damaging the sealing surface. A screen 37 is provided on the pressure-taking hole on the valve body 1 to prevent the filter screen 4 from being damaged in extreme cases, causing the pressure-taking hole to be blocked, thereby affecting the measurement accuracy of the pressure gauge 41. The damper at the tail of the main valve stem 6 in the main pressure reducing valve contacts the damper sleeve, and the guide sleeve 22 nested in the main nozzle 5 is passed through the head of the main valve stem 6, which can effectively prevent the valve stem from being stuck and improve the stability of the valve. The main pressure reducing valve is equipped with a limit plate 17 to reduce the vibration amplitude of the main regulating diaphragm assembly, reduce valve vibration, and extend the service life of the main diaphragm 16. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a cross-sectional view of a pilot-operated double-diaphragm control valve.

[0021] Figure 2 It is a longitudinal section view of a pilot-operated double-diaphragm control valve.

[0022] Figure 3 It is the cross-sectional view AA view of the pilot-operated double diaphragm control valve.

[0023] Figure 4 It is the front view of the pilot valve stem.

[0024] The numbers in the figure are: 1 is the valve body, 2 is the bushing joint, 3 is the compression spring, 4 is the filter screen, 5 is the main nozzle, 6 is the main valve stem, 7 is the main pressure regulating spring, 8 is the damper sleeve, 9 is the main end cover, 10 is the first O-ring, 11 is the main valve cover, 12 is the hexagonal bolt, 13 is the first diaphragm pressure plate, 14 is the main locking nut, 15 is the second diaphragm pressure plate, 16 is the main diaphragm, 17 is the limit plate, 18 is the second O-ring, 19 is the pilot end cover, 20 is the third O-ring, 21 is Partition, 22 is the guide sleeve, 23 is the valve core, 24 is the pilot nozzle, 25 is the pilot valve stem, 26 is the locking bolt, 27 is the pilot diaphragm, 28 is the pilot locking nut, 29 is the pilot pressure regulating spring, 30 is the T-type handwheel, 31 is the pilot pressure-bearing spring, 32 is the spring cover, 33 is the pilot valve cover, 34 is the flat gasket, 35 is the control guide tube, 36 is the control hole, 37 is the screen, 38 is the feedback hole, 39 is the pilot hole, 40 is the plug, 41 is the pressure gauge, and 42 is the fourth O-ring. DETAILED DESCRIPTION

[0025] The present invention is further described below by way of embodiments in conjunction with the accompanying drawings.

[0026] Example 1

[0027] like Figure 1 , Figure 2 and Figure 3As shown, a cross-sectional view of the present invention is given, and a high-performance pilot spring diaphragm pressure reducing valve proposed by the present invention comprises a valve body 1, a core-buffering joint 2, a clamping spring 3, a filter screen 4, a pilot pressure reducing valve and a main pressure reducing valve; the pilot pressure reducing valve is located at one side of the valve body 1, and the main pressure reducing valve is located at the center of the valve body 1; a filter screen 4 is provided at the medium inlet of the valve body 1, a clamping spring 3 is provided above the filter screen 4, and the medium inlet of the valve body 1 is connected to the core-buffering joint 2; the main pressure reducing valve and the pilot pressure reducing valve are communicated through the pilot hole 39, the control hole 36 and the feedback hole 38 of the valve body 1, and the control hole 36 on the valve body 1 is communicated with the main valve cover 11 through the control conduit 35; the process hole of the pilot hole 39 of the valve body 1 is provided with a plug 40 to prevent the upper and lower chambers from communicating, and a pressure gauge 41 is provided at the outer end of the process hole to detect the output pressure;

[0028] The main pressure reducing valve is a spring diaphragm type pressure reducing valve, which is composed of a main nozzle 5, a main valve stem 6, a main pressure regulating spring 7, a main end cover 9, a first O-ring 10, a main valve cover 11, a main diaphragm assembly, a limit plate 17 and a second O-ring 18. The main nozzle 5 extends into one end of the valve body 1, the valve body 1 and the main end cover 9 are connected through the first O-ring 10, and the main pressure regulating spring 7 is provided on the concave platform of the main end cover 9; a main valve stem 6 is provided between the main pressure regulating spring 7 and the main nozzle 5; a second O-ring 18 is provided between the limit plate 17 and the valve body 1, A main diaphragm assembly is arranged above the limit plate 17, and the main diaphragm assembly is composed of a first diaphragm pressure plate 13, a second diaphragm pressure plate 15 and a main diaphragm 16. The first diaphragm pressure plate 13 and the second diaphragm pressure plate 15 are arranged on the left and right sides of the main diaphragm 16, and the first diaphragm pressure plate 13, the second diaphragm pressure plate 15 and the main diaphragm 16 are fixed by a main locking nut 14; the edge of the main diaphragm assembly fits the main valve cover 11, and the main valve cover 11 is fixed to the valve body 1 by hexagonal bolts, thereby ensuring good sealing of the valve;

[0029] The pilot pressure reducing valve is a spring diaphragm type pressure reducing valve, which is composed of a pilot end cover 19, a third O-ring 20, a valve core 23, a pilot nozzle 24, a pilot valve stem 25, a pilot pressure regulating spring 29, a T-handwheel 30, a pilot pressure bearing spring 31, a pilot valve cover 33 and a pilot diaphragm assembly. The pilot diaphragm assembly is composed of a locking bolt 26, a pilot diaphragm 27 and a pilot locking nut 28. A third O-ring 20 is provided at the threaded recess of the valve body 1 and the pilot end cover 19 to ensure the sealing of the pilot pressure reducing valve; the pilot end cover 19 is provided with a pilot concave platform in the center. A pressure-bearing spring 31, one end of the valve core 23 is inserted into the pilot pressure-bearing spring 31, and the other end is sleeved on the pilot valve stem 25, and the end of the valve core 23 is connected to the pilot nozzle 24; the pilot valve stem 25 passes through the valve body 1 and is pressed against the pilot diaphragm assembly, a flat gasket 34 is provided between the pilot diaphragm assembly and the pilot valve cover 33, the pilot valve cover 33 is threadedly connected to the valve body 1, a pilot pressure-regulating spring 29 is provided under the pilot diaphragm assembly, a spring cover plate 32 is provided at the connection between the pilot pressure-regulating spring 29 and the pilot valve cover 33, and one end of the T-shaped handwheel 30 is pressed against the spring cover plate 32.

[0030] A fourth O-ring 42 is disposed between the valve body 1 and the control conduit 35 .

[0031] A screen 37 is provided on the pressure taking hole on the valve body 1 .

[0032] The damper sleeve 8 is nested in the center of the main end cover 9 .

[0033] The tail of the nozzle 5 is embedded in the guide sleeve 22 .

[0034] The pilot valve stem 25 is a bow-shaped structure.

[0035] The main valve cover 11 is provided with a control hole 36 .

[0036] The above-mentioned high-performance pilot spring diaphragm pressure reducing valve has a connection port of 3 / 4NPT, a diameter of DN20, a working medium of gas, a working temperature of -10~+60℃, a maximum input pressure of 2.4MPa, a maximum output pressure of 1.4MPa, and a maximum flow rate of 283m 3 / h; when the gas source pressure changes by ±0.1MPa, the outlet pressure changes by less than 0.5%; when the outlet flow rate fluctuates within the range of 5% to 100%, the outlet pressure changes by less than 5.5%. The data show that a high-performance pilot spring diaphragm pressure reducing valve has the significant advantages of compact structure, sensitive adjustment, fast response speed, stable pressure regulation, reliable sealing and wide application range.

Claims

1. A high-performance pilot spring diaphragm pressure reducing valve, comprising a valve body (1), a core plug connector (2), a compression spring (3), a filter screen (4), a pilot pressure reducing valve and a main pressure reducing valve; the pilot pressure reducing valve is located on one side of the valve body (1), and the main pressure reducing valve is located in the center of the valve body (1); a filter screen (4) is provided at the medium inlet of the valve body (1), a compression spring (3) is provided above the filter screen (4), and the medium inlet of the valve body (1) is connected to the core plug connector (2); the main pressure reducing valve and the pilot pressure reducing valve are communicated through a pilot hole (39), a control hole (36) and a feedback hole (38) of the valve body (1), and the control hole (36) on the valve body (1) is communicated with the main valve cover (11) through a control conduit (35); a plug (40) is provided at the process hole of the pilot hole (39) of the valve body (1) to prevent the upper and lower chambers from communicating with each other, and a pressure gauge (41) is provided at the outer end of the process hole to detect the output pressure; The main pressure reducing valve is a spring diaphragm type pressure reducing valve, which comprises a main nozzle (5), a main valve stem (6), a main pressure regulating spring (7), a main end cover (9), a first O-ring (10), a main valve cover (11), a main diaphragm assembly, a limit plate (17) and a second O-ring (18). The main nozzle (5) extends into one end of the valve body (1), the valve body (1) and the main end cover (9) are connected via the first O-ring (10), a main pressure regulating spring (7) is arranged on the concave platform of the main end cover (9); a main valve stem (6) is arranged between the main pressure regulating spring (7) and the main nozzle (5); a second limit plate (17) is arranged between the limit plate (17) and the valve body (1) An O-ring (18) is provided above the limit plate (17), and the main diaphragm assembly is composed of a first diaphragm pressure plate (13), a second diaphragm pressure plate (15) and a main diaphragm (16). The first diaphragm pressure plate (13) and the second diaphragm pressure plate (15) are provided on the left and right sides of the main diaphragm (16), and the first diaphragm pressure plate (13), the second diaphragm pressure plate (15) and the main diaphragm (16) are fixed by a main locking nut (14); the edge of the main diaphragm assembly is fitted with the main valve cover (11), and the main valve cover (11) and the valve body (1) are fixed by hexagonal bolts, thereby ensuring good sealing of the valve; The pilot pressure reducing valve is a spring diaphragm type pressure reducing valve, which is composed of a pilot end cover (19), a third O-ring (20), a valve core (23), a pilot nozzle (24), a pilot valve stem (25), a pilot pressure regulating spring (29), a T-type hand wheel (30), a pilot pressure bearing spring (31), a pilot valve cover (33) and a pilot diaphragm assembly. The pilot diaphragm assembly is composed of a locking bolt (26), a pilot diaphragm (27) and a pilot locking nut (28). A third O-ring (20) is provided at the threaded recess of the valve body (1) and the pilot end cover (19) to ensure the sealing of the pilot pressure reducing valve. The pilot end cover (19) is provided with a pilot pressure bearing spring on the central recess. Spring (31), one end of the valve core (23) is inserted into the pilot pressure-bearing spring (31), and the other end is sleeved on the pilot valve stem (25), and the end of the valve core (23) is connected to the pilot nozzle (24); the pilot valve stem (25) passes through the valve body (1) and is pressed against the pilot diaphragm assembly, a flat gasket (34) is provided between the pilot diaphragm assembly and the pilot valve cover (33), the pilot valve cover (33) is threadedly connected to the valve body (1), a pilot pressure regulating spring (29) is provided below the pilot diaphragm assembly, a spring cover plate (32) is provided at the connection between the pilot pressure regulating spring (29) and the pilot valve cover (33), and one end of the T-shaped hand wheel (30) is pressed against the spring cover plate (32); A screen (37) is provided on the pressure taking hole on the valve body (1); The damper sleeve (8) is nested in the center of the main end cover (9); The guide sleeve (22) is nested at the rear of the main nozzle (5).

2. A high performance pilot spring diaphragm pressure reducing valve according to claim 1, characterized in that: A fourth O-ring (42) is provided between the valve body (1) and the control conduit (35).

3. A high performance pilot spring diaphragm pressure reducing valve according to claim 1, characterized in that: The pilot valve stem (25) is of a bow-shaped structure.

4. A high performance pilot spring diaphragm pressure reducing valve according to claim 1, characterized in that: The main valve cover (11) is provided with a control hole (36).

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