A split double blade control butterfly valve

Abstract

The application relates to a split double-blade control butterfly valve. The valve body is provided with a valve seat, a semicircular first blade and a second blade are arranged in the cavity of the valve seat, the arc-shaped edges of the first blade and the second blade are sealed with the inner wall of the valve seat when being closed, the first blade and the second blade respectively seal half of the cavity of the valve seat to form a circular cross-section flow surface, a first valve shaft and a second valve shaft are vertically arranged in front of and behind the cavity of the valve seat, the two ends of the first valve shaft and the second valve shaft respectively pass through the valve seat and the valve body, the diameter edge of the first blade is fixedly connected with the first valve shaft, the symmetric axis of the second blade is fixedly connected with the second valve shaft, and one end of the first valve shaft and the second valve shaft is respectively connected with a first driving mechanism and a second driving mechanism arranged outside the valve body. The advantages and effects of the application are as follows: the flue gas passes through the double-blade progressive flow channel, the flow field is uniformly distributed, the fluid resistance is effectively reduced, the vortex area is eliminated, and the flow regulation linearity and stability are remarkably improved.

Description

Technical Field

[0001] This invention relates to a butterfly valve, and more particularly to a split-type double-blade control butterfly valve suitable for aluminum electrolysis flue gas purification systems in the field of electrolytic cell exhaust technology. Background Technology

[0002] In the aluminum electrolysis production process, the electrolytic cell generates a large amount of high-temperature, highly corrosive flue gas. This flue gas is collected through branch pipes and then enters the purification system via the main pipe. As a key channel for flue gas emission, the performance of the flow control valves in the branch pipes directly affects the flue gas collection efficiency, the stability of the production environment, and the precision of the electrolytic cell process control. Currently, traditional single-blade butterfly valves are commonly used for flue gas flow regulation in aluminum electrolysis cell branch pipe systems. While existing single-blade butterfly valves have a simple structure, this arrangement has the following problems in large-diameter pipelines (typically DN300-DN600): First, high fluid resistance and poor flow stability; second, high driving torque and high mechanical failure rate; third, low flow regulation accuracy, failing to meet the requirements of fine control. Furthermore, the control methods of existing butterfly valves mainly rely on manual operation or simple direct-drive electric actuators. Manual operation is labor-intensive, slow in response, and difficult to adapt to the automation requirements of modern aluminum electrolysis production. In terms of sealing structure, existing butterfly valves mostly use a single rubber or metal sealing ring. Under the long-term action of aluminum electrolysis flue gas containing corrosive components such as hydrogen fluoride and sulfur dioxide, and at temperatures typically between 120-200℃, the sealing material ages rapidly and requires frequent replacement and maintenance. Summary of the Invention

[0003] The purpose of this invention is to solve the problems of high fluid resistance, high driving torque, poor flow regulation accuracy, and unstable sealing performance of existing butterfly valves in aluminum electrolysis flue gas systems, and to propose a separate double-blade control butterfly valve.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: A split-type double-blade control butterfly valve includes a valve body and a valve seat disposed within the valve body. A semi-circular first blade and a second blade are disposed within the cavity of the valve seat. When closed, the arc-shaped edges of the first and second blades seal against the inner wall of the valve seat. The first and second blades respectively seal half of the valve seat cavity, forming a circular flow-crossing surface. A first valve shaft and a second valve shaft are vertically arranged front-to-back within the valve seat cavity. The two ends of the first and second valve shafts respectively extend out of the valve seat and the valve body. The diameter edge of the first blade is fixedly connected to the first valve shaft, and the axis of symmetry of the second blade is fixedly connected to the second valve shaft. One end of the first and second valve shafts is respectively connected to a first drive mechanism and a second drive mechanism disposed outside the valve body.

[0005] The first and second blades are made of heat-resistant steel or stainless steel with alumina ceramic coating.

[0006] The thickness of the first and second blades is 8 to 10 mm.

[0007] The horizontal gap between the first blade and the second blade is 0.5-1 mm.

[0008] The first and second blades have grooves on their arc-shaped edges, and a sealing element is provided in the groove. The sealing element is made of fluororubber or flexible graphite composite material.

[0009] The valve seat is made of stainless steel with hard alloy overlay, and the first and second valve shafts are made of high-temperature resistant self-lubricating material; the valve body is made of cast iron or cast steel with a wall thickness of 8 to 12 mm.

[0010] The other end of the first and second valve shafts is fitted with a dustproof sealing cap to prevent dust from entering.

[0011] The first and second drive mechanisms are equipped with worm gear pairs connected to the first and second valve shafts. The worm gear pairs are connected to a gear reduction group, which is connected to a drive motor. The gear reduction group is a two-stage cylindrical gear reduction group.

[0012] The drive motor is a three-phase asynchronous motor or a DC geared motor.

[0013] The second blade's diameter side is fixedly connected to one end of the elastic sealing strip. The elastic sealing strip is inclined downwards. When the first and second blades are closed, the elastic sealing strip contacts the first valve shaft to form a seal. The other end of the elastic sealing strip is tangent to the top surface of the first valve shaft. The elastic sealing strip is a high-temperature resistant fluororubber or metal graphite spiral wound gasket.

[0014] Advantages and effects of the present invention: This invention employs a spatially vertically separated double-blade structure. Flue gas flows through a progressive double-blade channel, resulting in a uniform flow field distribution, effectively reducing fluid resistance, eliminating vortex zones, and significantly improving the linearity and stability of flow regulation. The dual-shaft independent drive mechanism, through worm gear self-locking and a two-stage cylindrical gear reduction system, reduces opening and closing torque, achieving precise blade angle control, improving drive efficiency and adjustment accuracy, and meeting the requirements of automated fine control. The externally mounted drive motor, in conjunction with the reduction transmission mechanism, replaces manual operation. A double-sealing structure improves sealing reliability and extends service life. High-temperature and corrosion-resistant materials are selected to adapt to harsh working environments. It is suitable for DN300-DN600 diameter flue pipe systems and has broad application prospects. Attached Figure Description

[0015] Figure 1 This is an axial sectional view of the present invention.

[0016] Figure 2 This is a top sectional view of the present invention.

[0017] Figure 3 This is a schematic diagram of the spatial positions of the first and second blades of the present invention when they are in the closed state.

[0018] Figure 4 This is a schematic diagram of the spatial position of the two blades of the present invention when they are in the open state.

[0019] Figure 5 This is a cross-sectional view of the two blades of the present invention when they are closed.

[0020] In the figure: 1. First blade; 2. Second blade; 3. First valve shaft; 4. Second valve shaft; 5. Valve body; 6. Flange bolt hole; 7. Valve seat; 81. First drive mechanism; 82. Second drive mechanism; 9. Elastic sealing strip. Detailed Implementation

[0021] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0022] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0023] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0024] The preferred embodiments of this application are described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit this application.

[0025] As shown in the figure, a split-type double-blade control butterfly valve of the present invention includes a valve body 5 and a valve seat 7 disposed within the valve body 5. A semi-circular first blade 1 and a second blade 2 are disposed within the cavity of the valve seat 7. When closed, the arc-shaped edges of the first blade 1 and the second blade 2 seal against the inner wall of the valve seat 7. The first blade 1 and the second blade 2 respectively seal half of the cavity of the valve seat 7. At this time, the first blade 1 and the second blade 2 form a circular flow-cutting surface, such as... Figure 4 As shown, the first and second blades form a cross structure when fully open, allowing the flue gas to pass through the progressive flow channels of the two blades in a partially open state. This avoids the local turbulence and vortex zone formed by the drastic angle change of a single-blade butterfly valve, and significantly improves the linearity of flow regulation and flow stability.

[0026] In one embodiment, the first blade 1 and the second blade 2 are made of Q345R heat-resistant steel, which has excellent high-temperature strength and creep resistance, and is suitable for flue gas environments of 120-200℃.

[0027] In another embodiment, the first blade 1 and the second blade 2 can be made of stainless steel with alumina ceramic coating on the surface, which provides stronger corrosion resistance and is especially suitable for corrosive flue gas environments containing HF and SO2.

[0028] The thickness of the first blade 1 and the second blade 2 is 8 to 10 mm, which ensures structural strength while avoiding excessive weight that would make opening and closing difficult.

[0029] The horizontal gap between the first blade 1 and the second blade 2 is 0.5-1mm. The side of the diameter edge of the second blade 2 is fixedly connected to one end of the elastic sealing strip 9. The elastic sealing strip is inclined downwards. When the first blade 1 and the second blade 2 are closed, the elastic sealing strip 9 contacts the first valve shaft 3 to form a seal. The other end of the elastic sealing strip 9 is tangent to the top surface of the first valve shaft 3. The elastic sealing strip is made of high-temperature resistant fluororubber or metal graphite spiral wound gasket. This reduces fluid disturbance and improves the sealing effect when closed. This gap control, combined with the progressive adjustment characteristics of the double blade, enables the valve to maintain a stable flow field distribution at any opening degree, achieving fine adjustment of the flow rate. Furthermore, the high-temperature resistant fluororubber or metal graphite spiral wound gasket has a temperature resistance of up to 200℃ and has good elasticity and chemical corrosion resistance, making it suitable for higher temperature and pressure conditions and providing a longer service life.

[0030] Grooves are provided on the arc-shaped edges of the first blade 1 and the second blade 2, and sealing elements are installed within the grooves. The sealing elements are made of fluororubber or flexible graphite composite material. The sealing elements and the elastic sealing strip form a double seal, ensuring the sealing performance of the butterfly valve when the first blade 1 and the second blade 2 are closed.

[0031] The first valve shaft 3 and the second valve shaft 4 are arranged perpendicularly front to back within the cavity of the valve seat 7. Both ends of the first valve shaft 3 and the second valve shaft 4 extend out of the valve seat 7 and the valve body 5, respectively. The diameter side of the first blade 1 is fixedly connected to the first valve shaft 3, and the axis of symmetry of the second blade 2 is fixedly connected to the second valve shaft 4. One end of the first valve shaft 3 and the second valve shaft 4 are respectively connected to the first drive mechanism 81 and the second drive mechanism 82 located outside the valve body 5. This dual-shaft independent drive transmission mechanism independently drives the opening and closing of the first blade 1 and the second blade 2, achieving low flow resistance, high precision, and low torque flue gas regulation control, thereby significantly improving flow regulation accuracy and meeting the requirements of automated fine control. The valve body 5 is provided with flange bolt holes 6 for connection to pipelines.

[0032] The valve seat 7 is made of stainless steel with a hard alloy overlay, and the first valve shaft 3 and the second valve shaft 4 are made of high-temperature resistant self-lubricating material; the valve body 5 is made of cast iron or cast steel with a wall thickness of 8 to 12 mm. The surface of the valve seat 7 is treated with a composite multiphase ceramic coating to improve its wear resistance and corrosion resistance.

[0033] The other end of the first valve shaft 3 and the second valve shaft 4 is equipped with a dustproof sealing cover to prevent dust intrusion. In order to improve the service life of the valve shaft, all bearings are made of high temperature resistant self-lubricating material, which effectively blocks dust such as fluoride salts from entering the bearing parts and prevents the bearings from seizing or wearing out due to high temperature and dust environment.

[0034] The first drive mechanism 81 and the second drive mechanism 82 are provided with a worm gear pair connected to the first valve shaft 3 and the second valve shaft 4. The worm gear pair is connected to a gear reduction group, and the gear reduction group is connected to a drive motor. The gear reduction group is a two-stage cylindrical gear reduction group.

[0035] The drive motor is a three-phase asynchronous motor or a DC geared motor, which is mounted on an external bracket.

[0036] This invention is applicable to branch flue pipe systems with diameters from DN300 to DN600, meeting the installation requirements of pipes of different specifications. It is also suitable for high-temperature and highly corrosive (including HF and SO2) aluminum electrolysis branch flue pipe systems, ensuring long-term stable operation under harsh conditions.

[0037] The structure of this invention differs from that of traditional single-blade butterfly valves. Traditional single-blade butterfly valves, when partially open, experience drastic changes in blade angle and abrupt changes in flow channel cross-section, which easily leads to local turbulence and vortex zones, resulting in poor linearity of flow regulation. This invention, through a spatially vertically separated double-blade structure, allows flue gas to pass through the progressive flow channels of the two blades, resulting in a smooth flow field change. This effectively reduces flow field disturbances, eliminates vortex zones, reduces pressure loss, and significantly improves the linearity and accuracy of flow regulation.

[0038] It will be readily understood by those skilled in the art that the above embodiments can be freely combined and superimposed without conflict.

[0039] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application. The above are merely preferred embodiments of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of this application, and these improvements and modifications should also be considered within the protection scope of this application.

Claims

1. A split double-disc control butterfly valve comprising a valve body (5) and a valve seat (7) provided in the valve body (5), characterized in that A semi-circular first blade (1) and a second blade (2) are provided in the cavity of the valve seat (7). When closed, the arc-shaped edges of the first blade (1) and the second blade (2) are sealed with the inner wall of the valve seat (7). The first blade (1) and the second blade (2) respectively seal half of the cavity of the valve seat (7). The first blade (1) and the second blade (2) form a circular cross-sectional surface. The first valve shaft (3) and the second valve shaft (4) are arranged vertically in front and behind in the cavity of the valve seat (7). The two ends of the first valve shaft (3) and the second valve shaft (4) respectively pass through the valve seat (7) and the valve body (5). The diameter edge of the first blade (1) is fixedly connected to the first valve shaft (3). The axis of symmetry of the second blade (2) is fixedly connected to the second valve shaft (4). One end of the first valve shaft (3) and the second valve shaft (4) are respectively connected to the first drive mechanism (81) and the second drive mechanism (82) located outside the valve body (5).

2. The split double-disc control butterfly valve according to claim 1, wherein The first blade (1) and the second blade (2) are made of heat-resistant steel or stainless steel with alumina ceramic coating.

3. A split double-disc control butterfly valve according to claim 2, characterized in that The thickness of the first blade (1) and the second blade (2) is 8 to 10 mm.

4. A split double blade control butterfly valve according to claim 1, 2 or 3, characterized in that The horizontal gap between the first blade (1) and the second blade (2) is 0.5-1 mm.

5. A split double-disc control butterfly valve according to claim 4, characterized in that The first blade (1) and the second blade (2) have grooves on their arc-shaped edges, and a sealing element is provided in the groove. The sealing element is a fluororubber or flexible graphite composite material.

6. The split double-disc control butterfly valve according to claim 1, wherein The valve seat (7) is made of stainless steel with hard alloy overlay, the first valve shaft (3) and the second valve shaft (4) are made of high temperature resistant self-lubricating material; the valve body (5) is made of cast iron or cast steel with a wall thickness of 8 to 12 mm.

7. The split double blade control butterfly valve according to claim 1 or 7, characterized in that The other end of the first valve shaft (3) and the second valve shaft (4) is fitted with a dustproof sealing cover on the outside of the valve body (5) to prevent dust from entering.

8. The split double-disc control valve according to claim 1, wherein The first drive mechanism (81) and the second drive mechanism (82) are provided with a worm gear pair connected to the first valve shaft (3) and the second valve shaft (4). The worm gear pair is connected to the gear reduction group, and the gear reduction group is connected to the drive motor. The gear reduction group is a two-stage cylindrical gear reduction group.

9. A split-type double-blade control butterfly valve according to claim 8, characterized in that... The drive motor is a three-phase asynchronous motor or a DC geared motor.

10. A split-type double-blade control butterfly valve according to claim 5, characterized in that... The second blade (2) is fixedly connected to one end of the elastic sealing strip (9) on its diameter side. The elastic sealing strip (9) is inclined downward. When the first blade (1) and the second blade (2) are closed, the elastic sealing strip (9) contacts the first valve shaft (3) to form a seal. The other end of the elastic sealing strip (9) is tangent to the top surface of the first valve shaft (3). The elastic sealing strip is a high-temperature resistant fluororubber or metal graphite spiral wound pad.

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