Ultra-low-pressure large-flow self-operated gas pressure reducing valve

Abstract

The invention discloses an ultralow-pressure large-flow self-operated gas pressure reducing valve, and belongs to the technical field of gas pressure control. Comprising a valve body, a DN32 air inlet 2 and a DN65 air outlet are formed in the valve body, the pressure of the air outlet is fed back through a feedback channel, and the pressure can be led to a pressure cavity below a diaphragm through a drilled hole in the valve body. The ratio of the effective area of the diaphragm to the flow area of the valve disc is set to be 25: 1 to 35: 1, and the drift diameter combination of a DN32 inlet and a DN65 outlet is matched, so that stable output with the flow larger than 300 Nm / h under the ultra-low pressure of 0.02-0.03 MPa is achieved; and secondly, the first-stage pressure regulating assembly and the second-stage pressure stabilizing assembly are connected in series, the diaphragm feedback cavity is directly communicated to the downstream of the second-stage pressure stabilizing assembly, functional decoupling of flow regulation and pressure stabilization is achieved, precise and leakage-free presetting can be achieved through a regulating mechanism with a wedge block and a metal folding cylinder, and higher control precision is obtained.

Description

Technical Field

[0001] This invention relates to the field of gas pressure control equipment technology, and more specifically, to an ultra-low pressure, high flow rate self-operated gas pressure reducing valve. Background Technology

[0002] Gas pressure reducing valves are key components in industrial gas delivery systems, used to stably reduce high-pressure gas from upstream to the low-pressure state required by downstream equipment. In fields such as marine nitrogen inerting, semiconductor manufacturing, and fine chemicals, gas supply systems with extremely low operating pressures (e.g., 0.02 MPa to 0.03 MPa) but very high flow rate requirements (e.g., >300 Nm³ / h) are often needed. This "ultra-low pressure, high flow rate" condition places extremely high challenges on the continuous pressure stabilization capability and high flow capacity of the pressure reducing valve.

[0003] Currently, the output pressure of ordinary gas pressure reducing valves on the market is usually higher than 0.1 MPa. Even if a few models can reduce the output pressure to around 0.02 MPa, their output flow rate is often severely limited, typically far less than 100 Nm³ / h, which cannot meet the needs of high-flow-rate applications. This is mainly because, under ultra-low pressure conditions, maintaining a high flow rate requires a large valve opening, while the force balance system of traditional self-operated pressure reducing valves lacks sufficient sensitivity and cannot accurately respond to minute changes in outlet pressure, resulting in problems such as valve regulation lag, large pressure fluctuations, and inability to increase flow rate.

[0004] Existing technologies also include valves designed for specific low-pressure scenarios. For example, Chinese invention patent CN116538343A discloses a "self-operated low-pressure valve for a tank gas recovery system," which addresses the precise opening and closing, sealing, and resistance to downstream negative pressure interference in tank gas recovery systems at the hectopascal (Pa) level by using a gravity controller (counterweight plate) and a complex internal and external pressure channel switching mechanism. However, the core design goals of this valve are "on / off action" and "zero leakage," and its technical means (such as counterweight plate and channel switching) are very complex, making it entirely suitable for intermittent operation scenarios that do not require large flow rates. This solution neither addresses nor solves the technical challenge of achieving continuous and stable high-flow-rate (>300 Nm³ / h) output at a higher pressure range (0.02 MPa, i.e., 20 kPa). On the contrary, its complex structure introduces significant flow resistance, making it unsuitable for high-flow-rate applications.

[0005] Therefore, existing pressure reducing valves either cannot simultaneously meet the requirements of "ultra-low pressure" and "large flow rate," or, as shown in "CN116538343A," their design concept and structure run counter to the continuous pressure stabilization and large flow rate requirements of this invention. There is an urgent need for a completely new self-operated gas pressure reducing valve specifically designed for ultra-low pressure, large flow rate, and continuous pressure stabilization conditions. Summary of the Invention

[0006] To overcome the aforementioned deficiencies of the prior art, embodiments of the present invention provide an ultra-low pressure, high-flow self-operated gas pressure reducing valve. By setting the ratio of the effective diaphragm area to the valve disc flow area to 25:1 to 35:1, and employing a specific combination of a DN32 inlet and a DN65 outlet, the technical problem of flow limitation in traditional pressure reducing valves under ultra-low pressure (0.02-0.03MPa) conditions is solved. When the outlet pressure is 0.02MPa, the present invention can still maintain a rated flow rate greater than 300Nm³ / h. Compared with the limitation of existing valves mentioned in the background art, which have a flow rate of less than 100Nm³ / h under the same low pressure, this invention achieves a breakthrough improvement in flow performance, meeting the special needs of ultra-low pressure, high-flow gas supply in fields such as semiconductor manufacturing and fine chemicals. Furthermore, by adopting a diaphragm design with a large area ratio, the sensitivity of the actuator to ultra-low pressure signals is significantly enhanced, allowing for the detection of even small fluctuations in outlet pressure. At this time, the large-area diaphragm can generate sufficient driving force to drive the valve disc to respond quickly and stabilize the pressure fluctuation value within 0.002MPa. This effect effectively solves the problems of lag in regulation and large pressure fluctuation in traditional pressure reducing valves under ultra-low pressure conditions, as pointed out in the background technology. It provides a stable ultra-low pressure gas source guarantee for downstream processes. Finally, by innovatively adopting a structural design of series connection between a first-stage pressure regulating component and a second-stage pressure stabilizing component, the functions of "flow regulation" and "pressure stabilization" are decoupled. The first-stage component undertakes the main pressure drop and flow regulation, while the second-stage component is specifically responsible for precise pressure stabilization and directly senses the final outlet pressure through an independent feedback channel. This design eliminates the influence of inlet pressure fluctuation on pressure stabilization accuracy in the background technology, so that the valve can still maintain excellent pressure control when the inlet pressure fluctuates and the flow changes, further improving the practicality of the device and solving the problems mentioned in the background technology.

[0007] To achieve the above objectives, the present invention provides the following technical solution: an ultra-low pressure, high flow rate self-operated gas pressure reducing valve, comprising a valve body, a valve seat disposed within the valve body, a valve disc forming a sealing pair with the valve seat, a valve stem connected to the valve disc, a diaphragm for sensing outlet pressure, a pressure regulating spring providing a set force to the diaphragm, and an adjusting mechanism. The valve body has an inlet and an outlet at its two ends, respectively, and a feedback channel is provided to guide the outlet pressure to the pressure chamber below the diaphragm. The valve body is characterized in that the ratio of the effective area of ​​the diaphragm (Sdiaphragm) to the flow area of ​​the sealing pair at the valve disc (Svalve disc) ranges from 0.02 MPa to 0.03 MPa. The inlet diameter is DN32, with a designed inlet pressure of 0.5 MPa. The outlet diameter is DN65, with an outlet pressure setting range of 0.02 MPa to 0.03 MPa.

[0008] Preferably, the ratio of the effective area of ​​the diaphragm (Smembrane) to the flow area of ​​the sealing pair at the valve disc (Svalve disc) is 30:1.

[0009] It also relates to another type of ultra-low pressure, high flow rate self-operated gas pressure reducing valve, including a valve body, a valve core assembly disposed in the valve body, and a diaphragm actuator for sensing outlet pressure, characterized in that: the valve core assembly includes a primary pressure regulating component and a secondary pressure stabilizing component connected in series on the main flow channel; The primary voltage regulating component includes a throttling element with an adjustable or preset opening. The secondary voltage stabilizing component includes a movable valve disc that forms a sealing pair with the valve seat, and its valve stem is linked with the diaphragm actuator. The pressure feedback chamber of the diaphragm actuator is directly connected to the outlet channel downstream of the secondary voltage regulator component.

[0010] Preferably, the throttling element is a cage-type flow regulating plate structure.

[0011] Preferably, the opening degree of the primary voltage regulating component is preset and locked by a manual adjustment mechanism.

[0012] Preferably, the manual adjustment mechanism includes a horizontally arranged adjusting screw, a wedge, and a metal folding cylinder. The throttling element is slidably installed on the inner wall of the valve body or on the outer surface of the valve stem near the flow channel. The wedge is movably connected to the throttling element through an inclined plate. The adjusting screw is threadedly connected to the wedge to drive its horizontal movement. The metal folding cylinder is sealed between the valve body and the wedge to isolate the inner cavity of the valve body from the outside.

[0013] Preferably, the diaphragm actuator includes a diaphragm, and the ratio of the effective area of ​​the diaphragm (Smembrane) to the flow area of ​​the sealing pair at the movable valve disc (Svalve disc) ranges from 25:1 to 35:1.

[0014] Preferably, the pressure reducing valve has a rated flow rate greater than 300 Nm³ / h when the outlet pressure is between 0.02 MPa and 0.03 MPa.

[0015] Preferably, the pressure relief valve has an outlet pressure fluctuation of less than 0.002 MPa under normal operating conditions.

[0016] Preferably, the valve stem has a structure in which the upper and lower ends are respectively hinged to the diaphragm assembly and the valve disc.

[0017] The technical effects and advantages of this invention are as follows: 1. Achieve stable high-flow output under ultra-low pressure conditions. This invention solves the technical problem of limited flow rate of traditional pressure reducing valves under ultra-low pressure (0.02-0.03MPa) conditions by setting the ratio of the effective area of ​​the diaphragm to the flow area of ​​the valve disc to 25:1 to 35:1 and using a specific combination of DN32 inlet and DN65 outlet. When the outlet pressure is 0.02MPa, this invention can still maintain a rated flow rate of more than 300Nm³ / h. Compared with the limitation of existing valves mentioned in the background art, which have a flow rate of less than 100Nm³ / h under the same low pressure, this invention achieves a breakthrough improvement in flow performance and meets the special needs of ultra-low pressure and high flow rate gas supply in fields such as semiconductor manufacturing and fine chemicals.

[0018] 2. Improve the accuracy and stability of ultra-low voltage control. By adopting a diaphragm design with a large area ratio, the sensitivity of the actuator to ultra-low pressure signals is significantly enhanced. When the outlet pressure fluctuates slightly, the large-area diaphragm can generate sufficient driving force to drive the valve disc to respond quickly and stabilize the pressure fluctuation value within 0.002MPa. This effect effectively solves the problems of traditional pressure reducing valves in ultra-low pressure conditions, such as lag in regulation and large pressure fluctuations, as pointed out in the background technology, and provides a stable ultra-low pressure gas source guarantee for downstream processes.

[0019] 3. Achieve precise pressure control through functional decoupling This invention innovatively adopts a structural design that connects a primary pressure regulating component and a secondary pressure stabilizing component in series, decoupling the functions of "flow regulation" and "pressure stabilization". The primary component is responsible for the main pressure drop and flow regulation, while the secondary component is dedicated to precise pressure stabilization and directly senses the final outlet pressure through an independent feedback channel. This design eliminates the influence of inlet pressure fluctuations on pressure stabilization accuracy present in the prior art, enabling the valve to maintain excellent pressure control performance even when inlet pressure fluctuates and flow changes.

[0020] 4. Precision adjustment mechanism for achieving high sealing performance To address the leakage problem inherent in complex valve structures in the background art, this invention designs a manual adjustment mechanism based on wedge drive and metal folding cylinder sealing. This mechanism drives the wedge through a horizontally set adjusting screw, converting horizontal movement into vertical adjustment of the valve disc. At the same time, it utilizes the metal folding cylinder to achieve zero leakage at the dynamic seal. This structure not only ensures the accuracy of the opening adjustment but also solves the leakage risks inherent in traditional adjustment mechanisms, making it particularly suitable for industrial gas transportation scenarios with stringent sealing requirements. Attached Figure Description

[0021] Figure 1 This is a schematic cross-sectional view of the overall structure of Embodiment 1 of the present invention.

[0022] Figure 2 This is a schematic cross-sectional view of the overall structure of Embodiment 2 of the present invention.

[0023] Figure 3 for Figure 2 A partial enlarged cross-sectional schematic diagram of the manual adjustment mechanism; Figure 4 This is a schematic diagram of the metal folding tube structure of the present invention.

[0024] The attached diagram is labeled as follows: 1. Valve body; 2. Air inlet; 3. Air outlet; 4. Valve seat; 5. Valve disc (secondary pressure regulating component); 6. Valve stem; 7. Diaphragm; 8. Pressure regulating spring; 9. Adjusting screw; 10. Valve cover; 11. Throttling element (cage-type flow control plate); 12. Manual adjustment mechanism; 12a. Wedge block; 12b. Metal folding cylinder; 12c. Adjusting screw; 13. Feedback channel. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example

[0026] like Figure 1 As shown, an ultra-low pressure, high flow rate self-operated gas pressure reducing valve of the present invention includes a valve body 1, a valve seat 4, a valve disc 5, a valve stem 6, a diaphragm 7, a pressure regulating spring 8, and an adjusting screw 9. The valve body 1 is provided with a DN32 air inlet 2 and a DN65 air outlet 3. The pressure of the air outlet 3 is fed back through a feedback channel 13, which can be led to the pressure chamber below the diaphragm 7 through a drilled hole inside the valve body. A sealing part is provided at the connection between the pressure chamber and the flow channel of the valve body below. The lower end of the valve stem 6 passes through the sealing part and extends into the flow channel of the valve body below.

[0027] The core of this embodiment is that the ratio of the effective area Smembrane of the diaphragm 7 to the flow area Svalve disc of the sealing pair at the valve disc 5 is 30:1, preferably within the range of 25:1 to 35:1. By rotating the adjusting screw 9 to compress the pressure regulating spring 8, the outlet pressure can be set within the range of 0.02MPa to 0.03MPa. When the inlet pressure is 0.5MPa and the outlet pressure is set to 0.025MPa, the valve can stabilize the fluctuation of the outlet pressure within 0.002MPa under the condition that the flow rate is greater than 300Nm³ / h. The two ends of the valve stem 6 can be connected by a hinge to reduce lateral force and improve the flexibility of operation.

[0028] Example 2: Based on Example 1, a pre-adjustment structure was added inside the valve body 1.

[0029] Specifically, such as Figures 2 to 4As shown, this embodiment integrates a two-stage valve core structure in the valve body 1. The first-stage pressure regulating component includes a throttling element 11 (cage-type flow regulating plate) as a function, and the second-stage pressure regulating component is the movable valve disc 5 that forms a sealing pair with the valve seat 4. Its valve stem 6 is linked with the diaphragm 7 actuator. The pressure feedback chamber below the diaphragm 7 is directly connected to the downstream outlet flow channel of the second-stage pressure regulating component through an independent feedback channel (13) machined in the valve body or valve cover.

[0030] The opening degree of the primary voltage regulating component is preset and locked via the manual adjustment mechanism 12, such as... Figure 2 and Figure 3 As shown, the throttling element 11 (cage-type regulating plate) is fitted or slidably sleeved on the outside of the valve stem 6 via a slide rail 111 on its outer wall and a slide groove 112 on the inner wall of the valve body 1. It is independently adjustable and controlled relative to the movable valve disc 5. The lower end of the valve stem 6 passes through the throttling element 11 and is connected to the top of the movable valve disc 5 below, so that the throttling element 11 is vertically slidably installed in the valve body 1. The manual adjustment mechanism 12 includes a horizontally arranged adjusting screw 12c, a wedge 12a connected to the inner end of the adjusting screw 12c by a thread, and a metal folding cylinder 12b welded between the inner wall of the valve body 1 and the wedge 12a. The inclined surface of the wedge 12a and the inclined surface provided on the throttling element 11 (cage-type regulating plate) (formed in the guide groove on the outer wall of the cage-type regulating plate, such as...) Figure 3 (As shown) They cooperate and slide against each other. Rotating the adjusting screw 12c can drive the wedge block 12a to move horizontally left and right. The horizontal thrust is converted into vertical force through the inclined plate pair, which pushes the cage-type flow regulating plate 11 to move vertically up and down, thereby precisely adjusting the relative opening between it and the valve seat 4. The metal folding cylinder 12b completely isolates the adjusting screw 12c from the internal cavity of the valve body 1, achieving zero leakage at the dynamic seal. After adjustment, the position of the adjusting screw can be locked by tightening the lock nut. Secondly, it should be added that the pre-adjustment structure can be assembled by the inspection sealing cover set at the bottom of the valve body 1 and the inlet of the flow channel of the valve body 1. It is suitable for some special and complex working conditions. The upper end of the valve stem 6 can be connected to an external drive device (such as a manual wheel, electric or hydraulic actuator) to achieve manual or automatic control. The settings can be set according to the working conditions, and there are no restrictions here.

[0031] Working principle: During initial commissioning, the opening of the first-stage pressure regulating component is preset to a large position by the manual adjustment mechanism 12, so that it can bear most of the pressure drop of the system and provide a smooth passage for large flow. When the outlet pressure fluctuates due to changes in downstream gas consumption, the pressure is directly and without delay transmitted to the diaphragm 7, driving the second-stage pressure regulating component 5 to act quickly and accurately correct the pressure deviation. Since the second-stage pressure regulating component 5 only performs fine adjustment on the pressure after the first-stage coarse adjustment and only bears a very small pressure drop, its action is extremely sensitive and accurate. In this embodiment, the ratio of the effective area of ​​the diaphragm 7 to the flow area of ​​the sealing pair at the second-stage pressure regulating component 5 can also be set to 30:1 to further improve the sensitivity. This structure is particularly suitable for operating conditions with large inlet pressure fluctuations or extremely wide flow variation ranges, and can achieve lower pressure fluctuations than in Example 1, for example, <0.0015MPa.

[0032] Finally, the following points should be noted: First, in the description of this application, it should be noted that, unless otherwise specified and limited, the terms "installation", "connection", and "linkage" should be interpreted broadly, and can be mechanical or electrical connections, or internal connections between two components, or direct connections. "Up", "down", "left", "right", etc. are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may change. Secondly: The accompanying drawings of the embodiments disclosed in this invention only involve the structures involved in the embodiments disclosed in this invention. Other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of this invention can be combined with each other. In conclusion, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A self-operated gas pressure reducing valve with ultra-low pressure and large flow rate, comprising a valve body (1), a valve seat (4) disposed within the valve body (1), a valve disc (5) forming a sealing pair with the valve seat (4), a valve stem (6) connected to the valve disc (5), a diaphragm (7) for sensing the outlet pressure, a pressure regulating spring (8) providing a set force to the diaphragm (7), and an adjusting mechanism (9), wherein the valve body (1) is provided with an inlet (2) and an outlet (3) at both ends, and a feedback channel (13) is provided to guide the pressure at the outlet (3) to the pressure chamber below the diaphragm (7), characterized in that: The ratio of the effective area (Smembrane) of the diaphragm (7) to the flow area (Svalve) of the sealing pair at the valve disc (5) is between 25:1 and 35:

1. The inlet (2) has a diameter of DN32 and a designed inlet pressure of 0.5MPa. The outlet (3) has a diameter of DN65 and an outlet pressure setting range of 0.02MPa to 0.03MPa.

2. The ultra-low pressure, high flow rate self-operated gas pressure reducing valve according to claim 1, characterized in that: The ratio of the effective area (Smembrane) of the diaphragm (7) to the flow area (Svalve) of the sealing pair at the valve disc (5) is 30:

1.

3. A self-operated gas pressure reducing valve with ultra-low pressure and high flow rate, comprising a valve body (1), a valve core assembly disposed within the valve body (1), and a diaphragm actuator for sensing outlet pressure, characterized in that: The valve core assembly includes a primary pressure regulating component and a secondary pressure stabilizing component connected in series on the main flow channel; The primary voltage regulating component includes a throttling element (11) with adjustable or preset opening. The secondary voltage stabilizing component includes a movable valve disc (5) that forms a sealing pair with the valve seat (4), and its valve stem (6) is linked with the diaphragm actuator; The pressure feedback chamber of the diaphragm actuator is directly connected to the outlet channel downstream of the secondary voltage regulator component.

4. The ultra-low pressure, high flow rate self-operated gas pressure reducing valve according to claim 3, characterized in that: The throttling element (11) is a cage-type flow regulating plate structure.

5. The ultra-low pressure, high flow rate self-operated gas pressure reducing valve according to claim 3, characterized in that: The opening degree of the primary voltage regulating component is preset and locked by a manual adjustment mechanism (12).

6. The ultra-low pressure, high flow rate self-operated gas pressure reducing valve according to claim 5, characterized in that: The manual adjustment mechanism (12) includes a horizontally arranged adjusting screw (12c), a wedge (12a), and a metal folding cylinder (12b). The throttling element (11) is slidably installed on the inner wall of the valve body (1) or on the outer surface of the valve stem (6) near the flow channel. The wedge (12a) is slidably connected to the throttling element (11) through an inclined plate. The adjusting screw (12c) is threadedly connected to the wedge (12a) to drive it to move horizontally. The metal folding cylinder (12b) is sealed between the valve body (1) and the wedge (12a) to isolate the inner cavity of the valve body from the outside.

7. A self-operated gas pressure reducing valve with ultra-low pressure and large flow rate according to claims 3 to 6, characterized in that: The diaphragm actuator includes a diaphragm (7), and the ratio of the effective area (Smembrane) of the diaphragm (7) to the flow area (Svalve) of the sealing pair at the movable valve disc (5) is in the range of 25:1 to 35:

1.

8. A self-operated gas pressure reducing valve with ultra-low pressure and large flow rate according to claims 1 to 6, characterized in that: The pressure reducing valve has a rated flow rate greater than 300 Nm³ / h when the outlet pressure is between 0.02 MPa and 0.03 MPa.

9. A self-operated gas pressure reducing valve with ultra-low pressure and large flow rate according to claims 1 to 6, characterized in that: Under normal operating conditions, the pressure fluctuation of the pressure reducing valve is less than 0.002 MPa.

10. A self-operated gas pressure reducing valve with ultra-low pressure and large flow rate according to claims 1 to 6, characterized in that: The valve stem (6) is a structure in which the upper and lower ends are respectively connected to the diaphragm (7) assembly and the valve disc (5) by a hinge.

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