A flow regulating valve for boiler pulverized coal conveying pipeline

Abstract

This utility model relates to a flow regulating valve for boiler pulverized coal conveying pipelines, comprising a valve body, a valve core, an annular pressure bladder, a connecting part, and a pressure sensor. The valve body has a hollow cylindrical structure with an annular mounting cavity in the center. The valve core is a cylindrical sleeve made of polyurethane, coaxially fixed within the valve body, and its flow channel cross-sectional area is adjusted by radial elastic deformation. The annular pressure bladder is located within the mounting cavity and, after inflation, pressurizes the valve core inward. The connecting part includes multiple circumferentially distributed connectors to achieve synchronous entry and exit of pressurized gas. The pressure sensor detects the pressure inside the bladder in real time and feeds it back to the external control box, forming a closed-loop control. This valve replaces the traditional mechanical structure with elastic deformation, reducing pulverized coal erosion and wear, improving regulation accuracy and reliability, and is suitable for efficient flow control in boiler pulverized coal conveying systems.

Description

Technical Field

[0001] This utility model belongs to the field of industrial valve technology, specifically relating to a flow regulating valve for a boiler pulverized coal conveying pipeline. Background Technology

[0002] In coal-fired boiler systems, the flow rate of pulverized coal directly affects combustion efficiency and load response. Flow regulating devices are typically installed in pulverized coal conveying pipelines to achieve precise control of the pulverized coal flow rate and adapt to changes in boiler load. Currently, the commonly used regulating valves in this type of application are mostly mechanical valve plates, butterfly valves, or louvered structures, achieving flow regulation by changing the valve plate opening.

[0003] However, such valves face several significant problems when operating in pulverized coal media for extended periods. Pulverized coal gas flow is highly abrasive; the valve plate, bushing, and sealing structure of traditional mechanical valves are prone to wear under the scouring of high-speed, dust-laden airflow, leading to seal failure, drift in regulating characteristics, and even jamming. This not only reduces valve lifespan but also affects the reliability and accuracy of system control. Furthermore, mechanical valves are prone to generating localized eddies and sudden throttling during operation, resulting in pulverized coal deposition, flow channel blockage, or increased pressure fluctuations, further impacting system stability.

[0004] On the other hand, to achieve continuous and precise flow regulation, some existing technologies use pneumatic or electric actuators to drive the valve core in linear or rotary motion. However, these actuators are often complex in structure, have transmission backlash, and their moving parts are prone to jamming or failure in dusty and harsh environments, resulting in high maintenance frequency and high costs. In addition, the wear problem caused by the relative motion between the valve core and the valve seat remains prominent.

[0005] Therefore, a flow regulating valve for boiler pulverized coal conveying pipeline is proposed to address the current shortcomings. Utility Model Content

[0006] This utility model provides a flow regulating valve for a boiler pulverized coal conveying pipeline, which aims to solve the problems of existing mechanical regulating valves (such as butterfly valves, louvered valves, etc.) that cannot avoid the high abrasive erosion of pulverized coal media, are difficult to achieve high-precision continuous regulation, and are prone to jamming and wear of mechanical moving parts, resulting in short valve life, drift of regulating characteristics, poor control reliability, and frequent maintenance.

[0007] To achieve the above objectives, the technical solution adopted by this utility model is: to provide a flow regulating valve for a boiler pulverized coal conveying pipeline, comprising:

[0008] The valve body is a hollow cylindrical structure with openings at both ends, and has an annular mounting cavity in the middle.

[0009] The valve core is coaxially disposed inside the valve body, and the outer walls at both ends of the valve core are fixed to the inner wall of the valve body by bonding.

[0010] An annular pressure bladder is disposed within the annular mounting cavity, with its outer side fitting against the inner wall of the annular mounting cavity and its inner side contacting the outer wall of the valve core.

[0011] A connecting part is provided on the valve body for connecting the annular pressure bladder and the external control box, and for supplying or discharging gas into the annular pressure bladder.

[0012] A pressure sensor is installed inside the annular pressure bladder and electrically connected to an external control box to detect the gas pressure inside the annular pressure bladder in real time.

[0013] The external control box controls the gas flow based on the pressure signal fed back by the pressure sensor, thereby adjusting the pressure inside the annular pressure bladder and causing the valve core to undergo radial elastic deformation, thus changing the cross-sectional area of ​​its internal flow channel.

[0014] Preferably, the valve body further includes a sealing portion, the sealing portion comprising:

[0015] Two annular end plates are provided, and each end plate is coaxially disposed at both ends of the valve body along the axial direction of the valve body. The end plates are bonded and fixed to the corresponding ends of the valve core.

[0016] Two limiting rings are provided, each of which is coaxially disposed on the inner side of the corresponding end plate. The end of the valve core is provided with an annular connecting groove that cooperates with the corresponding limiting ring.

[0017] Preferably, the valve core is a cylindrical sleeve structure with equal wall thickness, and its interior forms a pulverized coal flow channel.

[0018] Preferably, the valve core is made of polyurethane elastomer.

[0019] Preferably, the annular pressure bladder is a hollow, annular, sealed bladder structure made of multiple layers of reinforced rubber.

[0020] Preferably, the connecting portion includes:

[0021] The valve body has multiple connectors, which are spaced apart circumferentially along the middle of the valve body. One end of each connector extends into the annular mounting cavity and communicates with the annular pressure bladder.

[0022] A protective cover is fixedly fitted onto the outside of the valve body, and each connector is located inside the protective cover to protect the air pipe connected to the connector.

[0023] Preferably, the valve body is provided with connecting flanges at both ends for connecting to external pulverized coal conveying pipelines.

[0024] The present invention has the following advantages due to the adoption of the above technical solution:

[0025] This invention achieves dynamic balance regulation of pulverized coal flow through the synergistic effect of an annular pressure bladder and an elastic valve core. The valve core is made of polyurethane elastomer, whose radial elastic deformation can precisely change the cross-sectional area of ​​the flow channel, overcoming the regulation lag or inaccuracy problems caused by pulverized coal adhesion in traditional butterfly valves. Simultaneously, the closed-loop control mechanism of the pressure sensor and the external control box ensures real-time matching of the valve opening with the target flow rate, significantly improving the valve's regulation accuracy and response speed.

[0026] This invention, by employing an annular pressure bladder as a pneumatic actuator and combining it with a multi-connector synchronous air intake structure, enables uniform and rapid deformation of the valve core, significantly improving the response speed and control accuracy of flow regulation, and meeting the requirements of rapidly changing boiler load conditions.

[0027] The valve core of this utility model is made of polyurethane elastomer material, which has good elasticity and wear resistance and can withstand the erosion of coal powder for a long time. The valve body and valve core are fixed by bonding and a limiting ring and connecting groove structure are set to effectively prevent the valve core from axial movement or circumferential sliding under pressure, ensuring efficient and reliable force transmission and extending the overall service life of the valve.

[0028] The inner diameter of the valve core of this utility model is consistent with the inner diameter of the pipe, achieving a seamless transition and avoiding eddy current wear and local scouring caused by the step structure; the integral sleeve valve core has extremely low flow resistance in the fully open state, and always maintains a continuous and smooth flow channel shape during the adjustment process, significantly reducing energy consumption and wear risk.

[0029] This invention achieves real-time monitoring and closed-loop control of the pressure inside the annular pressure bladder through a built-in pressure sensor, ensuring a precise correspondence between the valve core deformation and the target flow rate. The multi-connector design not only improves the uniformity of air intake but also provides redundancy protection, allowing the valve to operate normally even if a single air path fails, thus enhancing the overall reliability of the valve.

[0030] The end plate of this utility model cooperates with the valve body to achieve end sealing of the annular mounting cavity, preventing leakage of pressure medium; the protective cover structure protects the air circuit connection parts from mechanical damage and dust intrusion, ensuring long-term stable operation of the valve in harsh industrial environments. Attached Figure Description

[0031] Figure 1 A schematic diagram of the structure of a flow regulating valve for a boiler pulverized coal conveying pipeline provided in this embodiment of the utility model;

[0032] Figure 2 An exploded view of a flow regulating valve for a boiler pulverized coal conveying pipeline provided for an embodiment of this utility model;

[0033] Figure 3 A schematic diagram of the internal structure of a flow regulating valve for a boiler pulverized coal conveying pipeline provided for an embodiment of this utility model;

[0034] Figure 4 A schematic diagram of the main structure of a flow regulating valve for a boiler pulverized coal conveying pipeline provided in this embodiment of the present invention;

[0035] Figure 5 for Figure 3 Sectional view at point AA;

[0036] Figure 6 for Figure 5 A magnified view of a section at point B.

[0037] Figure 7 for Figure 5 A magnified view of a section at point C.

[0038] Figure 8 This is a schematic diagram of the structure of a boiler pulverized coal conveying pipeline flow regulating valve with the protective cover removed, provided for an embodiment of this utility model.

[0039] Explanation of reference numerals in the attached figures:

[0040] 1. Valve body; 11. Annular mounting cavity;

[0041] 2. Valve core; 21. Annular connecting groove;

[0042] 3. Annular pressure bladder;

[0043] 4. Connecting part; 41. Connector; 42. Protective cover;

[0044] 5. Pressure sensor;

[0045] 6. Sealing part; 61. End plate; 62. Limiting ring;

[0046] 7. Connecting flange. Detailed Implementation

[0047] To make the technical problems, solutions, and beneficial effects of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0048] This utility model discloses a flow regulating valve for a boiler pulverized coal conveying pipeline, comprising:

[0049] The valve body 1 is a hollow cylindrical structure with openings at both ends, forming the main structure of the valve, bearing and connecting all other components, and withstanding internal pressure; the valve body 1 has an annular mounting cavity 11 in the middle, which is used to accommodate the annular pressure bladder 3 and to constrain the outward expansion of the annular pressure bladder 3.

[0050] During use, a mounting base is provided for valve core 2 to prevent circumferential or axial sliding when valve core 2 is deformed under pressure, thus ensuring efficient and reliable force transmission.

[0051] Furthermore, the valve body 1 is provided with connecting flanges 7 at both ends for connecting to external pulverized coal conveying pipelines to form a continuous conveying path.

[0052] Valve core 2 is a cylindrical sleeve structure with equal wall thickness, and its interior forms a pulverized coal flow channel. Valve core 2 is coaxially set inside valve body 1. The outer walls at both ends of valve core 2 are fixed to the inner wall of valve body 1 by bonding. The flow rate is adjusted by changing the cross-sectional area of ​​the flow channel through its own radial elastic deformation.

[0053] During implementation, the two ends of the valve core 2 are bonded and fixed to the inner wall of the valve body 1 to prevent pressure from shifting while effectively transmitting pressure, thus ensuring the stability of the valve core 2 under pressure.

[0054] Meanwhile, the valve core 2 has the same inner diameter as the external pulverized coal conveying pipeline, achieving a seamless transition and avoiding steps at the connection point that could cause eddy current wear.

[0055] The valve core 2 is made of polyurethane elastomer, which has good elasticity and excellent wear resistance, and can withstand the erosion of coal powder for a long time. At the same time, its adhesion to the valve body 1 ensures the seal between the valve core 2 and the valve body 1.

[0056] The valve body 1 also includes a sealing part 6, which includes:

[0057] Two end plates 61 are provided and are in the shape of a ring. Each end plate 61 is coaxially disposed at both ends of the valve body 1 along the axial direction of the valve body 1. The inner diameter of the end plate 61 is the same as the inner diameter of the valve core 2. The end plate 61 is bonded and fixed to the corresponding ends of the valve core 2.

[0058] The end plate 61 is bonded to the end of the valve core 2, and through its cooperation with the valve body 1, it seals both ends of the annular mounting cavity 11 to prevent leakage of the pressure medium and to provide auxiliary fixation for the valve core 2.

[0059] There are two limiting rings 62, each of which is coaxially arranged on the inner side of the corresponding end plate 61. The end of the valve core 2 is provided with an annular connecting groove 21 that cooperates with the corresponding limiting ring 62.

[0060] The engagement of the annular connecting groove 21 and the limiting ring 62 provides axial positioning, preventing the valve core 2 from undergoing axial displacement or end warping under pressure, thus ensuring controllable deformation and reliable sealing.

[0061] An annular pressure bladder 3 is disposed in an annular mounting cavity 11, with its outer side fitting against the inner wall of the annular mounting cavity 11 and its inner side contacting the outer wall of the valve core 2.

[0062] In this embodiment, the annular pressure bladder 3 is a hollow annular sealed bladder structure made of multi-layered reinforced rubber.

[0063] During implementation, the annular pressure bladder 3 acts as a pneumatic actuator. When pressurized gas is introduced into the annular pressure bladder 3, it expands. Since its outward expansion is restricted by the valve body 1, the pressure is forced to be transmitted inward, uniformly squeezing the valve core 2 and causing it to undergo radial contraction deformation.

[0064] The connecting part 4 is provided on the valve body 1 and is used to connect the annular pressure bladder 3 and the external control box, and to supply or discharge gas into the annular pressure bladder 3.

[0065] Connecting part 4 includes:

[0066] Multiple connectors 41 are provided, the specific number of which is determined according to the valve diameter and the required synchronous capacity. In this embodiment, there are four connectors 41, which can realize rapid pressurization and depressurization of the annular pressure bladder 3, improve the response speed of the valve, and enable it to reach the target opening more quickly to meet the adjustment needs of rapid changes in boiler load. At the same time, multiple connectors 41 realize synchronous air intake of the annular pressure bladder 3, realize uniform expansion of the annular pressure bladder 3, avoid uneven and twisted deformation of the valve core 2 in the circumferential direction, and ensure the service life of the valve core 2.

[0067] In addition, the multiple connectors 41 ensure that if any connector 41 or its connected air pipe becomes blocked during use, the remaining connectors 41 can still continue to operate, thus improving the overall reliability of the valve.

[0068] Each connector 41 is spaced circumferentially along the middle of the valve body 1. One end of each connector 41 extends into the annular mounting cavity 11 and communicates with the annular pressure bladder 3, thus realizing the connection of the air passage of the annular pressure bladder 3.

[0069] Specifically, the connector 41 has external threads at both ends for connecting the annular pressure bladder 3 and the air pipe of the external control box.

[0070] The protective cover 42 is fixedly sleeved on the outside of the valve body 1, and each connector 41 is located inside the protective cover 42 to protect the air pipe connected to the connector 41.

[0071] The protective cover 42 is provided to protect all connectors 41 and the air pipes connected to them from external mechanical damage, dust accumulation or environmental influences, while ensuring a clean appearance.

[0072] Pressure sensor 5 is installed inside the annular pressure bladder 3 and electrically connected to the external control box to detect the gas pressure inside the annular pressure bladder 3 in real time.

[0073] During implementation, the external control box controls the gas flow based on the pressure signal fed back by the pressure sensor 5, thereby adjusting the pressure inside the annular pressure bladder 3, causing the valve core 2 to undergo radial elastic deformation, thus changing the cross-sectional area of ​​its internal flow channel and achieving flow regulation.

[0074] In specific implementation of this utility model:

[0075] 1) Initial state:

[0076] When the external control box does not supply pressurized gas into the annular pressure bladder 3, the pressure inside the annular pressure bladder 3 is close to the ambient pressure. At this time, the valve core 2 is in a fully relaxed natural state due to the elasticity of its own material. Its inner diameter is exactly the same as the inner diameter of the upstream and downstream pulverized coal conveying pipelines, forming a smooth, continuous, and unobstructed flow channel. The pulverized coal airflow can pass smoothly, and the valve is in the fully open state, with maximum flow and minimum flow resistance.

[0077] 2) Adjustment process:

[0078] When the boiler control system needs to reduce the amount of pulverized coal delivered, the external control box receives a command to reduce the flow rate.

[0079] The external control box sends a signal to activate the air source, simultaneously filling the annular pressure bladder 3 with compressed gas through multiple connectors 41 of the connecting part 4. The annular pressure bladder 3 begins to expand, but its outward expansion is constrained by the rigid wall of the annular mounting cavity 11 in the valve body 1. Therefore, all the pressure is converted into an inward radial force, which is evenly applied to the outer wall of the valve core 2.

[0080] Under uniform circumferential pressure, valve core 2 undergoes elastic deformation, resulting in uniform and synchronous radial contraction of its flow channel cross-section, thus reducing the flow area. This creates a throttling effect on the pulverized coal gas flow through the valve, achieving the purpose of reducing the flow rate.

[0081] 3) Closed-loop control and maintenance:

[0082] The pressure sensor 5 is directly installed inside the annular pressure bladder 3 to detect the gas pressure value inside the annular pressure bladder 3 in real time, and converts the detected pressure signal into an electrical signal to be transmitted to the external control box.

[0083] The external control box compares the feedback signal received from the pressure sensor 5 with the target pressure value corresponding to the current flow demand.

[0084] Based on the deviation after comparison, the external control box dynamically stabilizes the pressure inside the annular pressure bladder 3 within the target range by controlling the filling or venting of gas. Since there is a definite correspondence between the pressure and the deformation (i.e., opening degree) of the valve core 2, the valve opening degree can be stabilized at the required position, thereby maintaining the pulverized coal flow rate at the set value.

[0085] 4) Recovery process:

[0086] When it is necessary to increase the pulverized coal flow rate, the external control box issues a command to discharge part of the compressed gas in the annular pressure bladder 3 through multiple connectors 41 of the connecting part 4, thereby reducing the pressure inside the annular pressure bladder 3.

[0087] When the pressure on valve core 2 decreases, it begins to rebound due to its own elastic restoring force, and the cross-sectional area of ​​the flow channel increases uniformly. At this time, the flow rate increases accordingly until the pressure inside the annular pressure bladder 3 and the elastic force of valve core 2 reach equilibrium, or the valve returns to the fully open state.

[0088] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A flow regulating valve for a boiler pulverized coal conveying pipeline, characterized in that, include: The valve body (1) has a hollow cylindrical structure with openings at both ends, and has an annular mounting cavity (11) in the middle. The valve core (2) is coaxially disposed inside the valve body (1), and the outer walls of both ends of the valve core (2) are fixed to the inner wall of the valve body (1) by adhesive bonding; An annular pressure bladder (3) is disposed in the annular mounting cavity (11), with its outer side fitting against the inner wall of the annular mounting cavity (11) and its inner side contacting the outer wall of the valve core (2). The connecting part (4) is provided on the valve body (1) for connecting the annular pressure bladder (3) and the external control box, and for supplying or discharging gas into the annular pressure bladder (3); A pressure sensor (5) is installed inside the annular pressure bladder (3) and electrically connected to an external control box for real-time detection of the gas pressure inside the annular pressure bladder (3). The external control box controls the gas flow based on the pressure signal fed back by the pressure sensor (5) to adjust the pressure inside the annular pressure bladder (3), causing the valve core (2) to undergo radial elastic deformation, thereby changing the cross-sectional area of ​​its internal flow channel.

2. The boiler pulverized coal conveying pipeline flow regulating valve as described in claim 1, characterized in that, The valve body (1) also includes a sealing part (6), which includes: Two end plates (61) are provided and are in a ring shape. Each end plate (61) is coaxially disposed at both ends of the valve body (1) along the axial direction of the valve body (1). The end plates (61) are bonded and fixed to the corresponding ends of the valve core (2). Two limiting rings (62) are provided, and each limiting ring (62) is coaxially disposed on the inner side of the corresponding end plate (61). The end of the valve core (2) is provided with an annular connecting groove (21) that cooperates with the corresponding limiting ring (62).

3. The boiler pulverized coal conveying pipeline flow regulating valve as described in claim 1, characterized in that: The valve core (2) is a cylindrical sleeve structure with equal wall thickness, and its interior forms a coal powder flow channel.

4. The boiler pulverized coal conveying pipeline flow regulating valve as described in claim 3, characterized in that: The valve core (2) is made of polyurethane elastomer.

5. The boiler pulverized coal conveying pipeline flow regulating valve as described in claim 1, characterized in that: The annular pressure bladder (3) is a hollow annular sealed bladder structure made of multi-layered reinforced rubber.

6. The boiler pulverized coal conveying pipeline flow regulating valve as described in claim 1, characterized in that, The connecting part (4) includes: Connector (41) is provided in multiple ways. Each connector (41) is arranged circumferentially along the middle of the valve body (1). One end of each connector (41) extends into the annular mounting cavity (11) and communicates with the annular pressure bladder (3). The protective cover (42) is fixedly sleeved on the outside of the valve body (1), and each of the connectors (41) is located inside the protective cover (42) to protect the air pipe connected to the connector (41).

7. The boiler pulverized coal conveying pipeline flow regulating valve as described in claim 1, characterized in that: The valve body (1) is provided with connecting flanges (7) at both ends for connecting to external pulverized coal conveying pipelines.

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