Protective device for automatically controlling secondary air door for heat recovery coking

Abstract

The utility model relates to a protective device for automatically controlling a secondary air door for heat recovery coking, which comprises an air inlet pipe communicated with a secondary air port of a heat recovery coke oven, a valve plate rotationally arranged in the air inlet pipe through a valve rod, and an electric actuator fixedly arranged below the valve rod and in transmission connection with the valve rod, the lower portion of the valve rod is a heat resisting section of a hollow tubular structure, an air inlet is formed in the peripheral side of the lower portion of the heat resisting section, an air outlet is formed in the peripheral side of the upper portion of the heat resisting section, an upper flange is arranged at the bottom end of the heat resisting section, the output end of the electric actuator is fixedly connected with a transmission shaft upwards, and a lower flange is arranged at the top end of the transmission shaft. A U-shaped heat insulation plate is arranged on the side, close to the heat recovery coke oven, of the electric actuator, the vertical part of the heat insulation plate is fixedly connected with the electric actuator, the upper horizontal part is rotationally connected with the transmission shaft, and the lower horizontal part is located below the electric actuator. Effective heat insulation protection of the electric actuator can be achieved from the upper side and the lower side, and the electric actuator is more practical.

Description

Technical Field

[0001] This utility model belongs to the field of heat insulation and protection technology, specifically relating to a protective device for automatic control of secondary air dampers used in heat recovery coking. Background Technology

[0002] Currently, secondary air intake ducts in heat recovery coke ovens are typically equipped with electric regulating valves or similar valves that work in conjunction with the system's automatic control to achieve automatic regulation of the secondary air intake. The valve stem of the electric regulating valve is driven by a matching electric actuator, which in turn rotates the corresponding valve plate, thus achieving opening, closing, and degree of adjustment. However, in actual use, on the one hand, heat from the four arches at the bottom of the coke oven is transferred from top to bottom to the electric actuator via the valve stem; on the other hand, the heat from the high-temperature gas discharged from the heat dissipation holes at the bottom of the coke oven also impacts the electric actuator from bottom to top. This causes the electric actuator to be subjected to heat from both sides for extended periods, significantly reducing its operational stability and lifespan. The high failure rate of the electric actuator hinders the long-term stable automatic regulation of secondary air and requires improvement. Utility Model Content

[0003] In view of this, the purpose of this utility model is to provide a protective device for automatic control of secondary air dampers used in heat recovery coking, which can effectively insulate and protect the electric actuator from both the top and bottom sides, so as to solve the above problems.

[0004] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a protective device for automatic control of a secondary air damper for heat recovery coking, comprising an air inlet pipe connected to the secondary air inlet of a heat recovery coking oven, a valve plate rotatably disposed in the air inlet pipe via a valve stem, and an electric actuator fixed below the valve stem and drivenly connected to the valve stem. The lower part of the valve stem is a hollow tubular heat-insulating section. The lower circumference of the heat-insulating section is evenly provided with several air inlets, and the upper circumference is evenly provided with several air outlets. The bottom end of the heat-insulating section is fixedly provided with an upper flange. The output end of the electric actuator faces upward and is coaxially fixedly connected to a drive shaft. The top end of the drive shaft is fixedly provided with a lower flange. The upper flange and the lower flange are connected by several bolt assemblies, and a heat-insulating gasket is sandwiched between the two flanges. A U-shaped heat-insulating plate is provided on the side of the electric actuator near the heat recovery coking oven. The opening of the heat-insulating plate faces the electric actuator, and its vertical part is fixedly connected to the electric actuator, its upper horizontal part is rotatably connected to the drive shaft, and its lower horizontal part is located below the electric actuator.

[0005] Preferably, both the upper flange and the lower flange are made of aluminum alloy.

[0006] Preferably, the heat insulation pad is made of asbestos or aluminum foam.

[0007] Preferably, the heat insulation plate consists of a main support plate and reinforcing heat insulation plates fixed on the inner and outer sides of the main support plate.

[0008] Preferably, the main support plate is made of steel plate or heat-insulating gypsum board.

[0009] Preferably, the reinforced heat insulation board is made of aluminum foam.

[0010] The beneficial effects of this utility model are as follows: In use, the electric actuator is electrically connected to the central control system of the existing heat recovery coke oven to facilitate the automatic control and adjustment of the valve plate's opening and closing and its degree of opening. During operation, on the one hand, the heat transferred from the valve stem to the electric actuator from top to bottom passes through the hollow heat-resistant section. Since air is not a conductor of heat, the air within the cavity of the heat-resistant section can initially block and effectively absorb the transferred heat. Simultaneously, because the heat is transferred from top to bottom, the air temperature at the upper part of the cavity is higher than that at the lower part. According to the principle of hot air buoyancy, the hotter air rises and flows out through the outlet, creating a negative pressure. This allows the cooler air to flow into the cavity through the inlet, thus forming a certain airflow trajectory, further effectively preventing heat from being transferred downwards. Subsequently, the heat-insulating gasket between the upper and lower flanges provides further effective insulation. Together, these features effectively prevent heat from being transferred from the bottom four-arched structure of the heat recovery coke oven to the electric actuator via the valve stem from top to bottom. On the other hand, the U-shaped heat insulation plate can effectively shield and protect the electric actuator, effectively preventing the heat discharged from the heat dissipation holes at the bottom of the heat recovery coke oven from impacting the electric actuator from bottom to top. Furthermore, the horizontal part at the top of the heat insulation plate can further block the heat transferred from top to bottom. With the synergistic cooperation of the two structures, a higher quality heat insulation protection can be formed for the electric actuator, thereby effectively improving the working stability and service life of the electric actuator, reducing the failure rate of the electric actuator, and being more conducive to the long-term stable automatic adjustment of secondary air. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the main structure of this utility model;

[0012] Figure 2 This is a schematic diagram of the main cross-sectional structure of the lower part of the valve stem of this utility model;

[0013] Figure 3 This is a schematic diagram of the main structure of the heat insulation board of this utility model.

[0014] The diagram is labeled as follows: 1 is the heat recovery coke oven, 2 is the air inlet pipe, 3 is the valve plate, 4 is the valve stem, 5 is the electric actuator, 6 is the heat insulation section, 7 is the air inlet, 8 is the air outlet, 9 is the upper flange, 10 is the drive shaft, 11 is the lower flange, 12 is the bolt assembly, 13 is the heat insulation pad, 14 is the heat insulation plate, 15 is the main support plate, 16 is the reinforced heat insulation plate, and the arrows indicate the direction of heat transfer. Detailed Implementation

[0015] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0016] like Figures 1 to 3 As shown, a protective device for automatic control of a secondary air damper in a heat recovery coking oven includes an air inlet pipe 2 connected to the secondary air inlet of a heat recovery coke oven 1, a valve plate 3 rotatably disposed in the air inlet pipe 2 via a valve stem 4, and an electric actuator 5 fixed below the valve stem 4 and drivenly connected to the valve stem 4. The lower part of the valve stem 4 is a hollow tubular heat-insulating section 6. Several air inlets 7 are evenly distributed on the lower circumference of the heat-insulating section 6, and several air outlets 8 are evenly distributed on the upper circumference. An upper flange 9 is fixedly disposed at the bottom end of the heat-insulating section 6. The output end of the electric actuator 5 faces upward and is coaxially fixedly connected to a drive shaft 10. A lower flange 11 is fixedly disposed at the top end of the drive shaft 10. The upper flange 9 and the lower flange 11 are connected by several bolt assemblies 12, and a heat-insulating gasket 13 is sandwiched between the two flanges. A U-shaped heat insulation plate 14 is provided on the side of the electric actuator 5 near the heat recovery coke oven 1. The opening of the heat insulation plate 14 faces the electric actuator 5 and its vertical part is fixedly connected to the electric actuator 5. Its upper horizontal part is rotatably connected to the transmission shaft 10, and its lower horizontal part is located below the electric actuator 5.

[0017] In use, the electric actuator 5 is electrically connected to the central control system of the existing heat recovery coke oven 1 to facilitate the automatic control and adjustment of the opening and closing of the valve plate 3 and the opening degree. During operation, on the one hand, the heat transferred from the valve stem 4 to the electric actuator 5 from top to bottom can first pass through the hollow heat-insulating section 6. Since air is not a conductor of heat, the air in the cavity of the heat-insulating section 6 can be used to initially block the heat and effectively absorb the transferred heat. At the same time, since the heat is transferred from top to bottom, the air temperature in the upper part of the cavity is higher than that in the lower part of the cavity. According to the principle of hot air buoyancy, the hotter air can rise and flow out through the air outlet 8, thus forming a negative pressure. This allows the colder air to flow into the cavity through the air inlet 7, thus forming a certain airflow trajectory, which can further effectively prevent the heat from being transferred downward. Subsequently, the installation of the heat insulation pad 13 between the upper flange 9 and the lower flange 11 provides effective heat insulation again. Together, they effectively prevent heat from being transferred from the bottom of the four-arched structure of the heat recovery coke oven 1 to the electric actuator 5 via the valve stem. On the other hand, the U-shaped heat insulation plate 14 effectively shields and protects the electric actuator 5, preventing heat from the heat dissipation holes at the bottom of the heat recovery coke oven 1 from impacting the electric actuator 5 from bottom to top. Furthermore, the horizontal portion at the top of the heat insulation plate 14 further blocks heat transfer from top to bottom. The synergistic effect of these two structures provides higher-quality heat insulation protection for the electric actuator 5, thereby effectively improving its operational stability and service life, reducing its failure rate, and facilitating long-term stable automatic adjustment of the secondary air.

[0018] In this embodiment, both the upper flange 9 and the lower flange 11 are made of aluminum alloy, which is a type of conventional heat-insulating flange. It has good heat insulation and fire-retardant properties, which can further block the transfer of heat to the electric actuator and provide better heat insulation protection for the electric actuator.

[0019] In this embodiment, the heat insulation pad 13 is made of asbestos or aluminum foam. Both asbestos and aluminum foam are existing materials with excellent heat insulation properties. They can be selected according to the actual situation, thereby providing effective heat insulation protection for the electric actuator 5.

[0020] In this embodiment, the heat insulation plate 14 is composed of a main support plate 15 and a reinforcing heat insulation plate 16 fixed on the inner and outer sides of the main support plate 15, so as to ensure the structural strength and heat insulation effect of the heat insulation plate 14.

[0021] In this embodiment, the main support plate 15 is made of steel plate or heat-insulating gypsum board, both of which are existing materials and have good heat insulation, lightweight and high strength properties, which can effectively ensure the overall structural strength and heat insulation effect of the heat insulation board 14.

[0022] In this embodiment, the reinforcing heat insulation board 16 is made of aluminum foam, which can further improve the heat insulation and protection effect of the entire heat insulation board. In addition, this material also has excellent damping, energy absorption, shock absorption, corrosion resistance and other characteristics. While providing heat insulation and protection, it can also play a certain role in shock absorption and corrosion protection, which is more conducive to the long-term stable operation of the electric actuator 5.

[0023] 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, improvements, etc., 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 protection device for automatic control of a secondary air damper for heat recovery coking, comprising an air inlet pipe connected to a secondary air inlet of a heat recovery coke oven, a valve plate provided in the air inlet pipe and rotated by a valve rod, and an electric actuator fixed below the valve rod and in driving connection with the valve rod, characterized in that, The lower part of the valve stem is a heat insulation section of hollow tubular structure, the lower part of the heat insulation section is uniformly provided with a plurality of air inlets on the circumferential side, and the upper part of the heat insulation section is uniformly provided with a plurality of air outlets on the circumferential side, the bottom end of the heat insulation section is fixedly provided with an upper flange, the output end of the electric actuator is coaxially fixedly connected with a transmission shaft in the upward direction, the top end of the transmission shaft is fixedly provided with a lower flange, the upper flange and the lower flange are connected through a plurality of bolt assemblies and the heat insulation pad is clamped between the two flanges, one side of the electric actuator close to the heat recovery coke oven is provided with a U-shaped heat insulation plate, the opening of the heat insulation plate faces the electric actuator, the vertical part of the heat insulation plate is fixedly connected with the electric actuator, the horizontal part of the upper part of the heat insulation plate is rotatably connected with the transmission shaft, and the horizontal part of the lower part of the heat insulation plate is located below the electric actuator.

2. The guard device for automatic control of the secondary air damper for heat recovery coking according to claim 1, characterized in that, The upper flange and the lower flange are both made of aluminum alloy material.

3. The guard device for automatic control of the secondary air damper for heat recovery coking according to claim 1, characterized in that, The heat insulation pad is made of asbestos or foamed aluminum material.

4. The guard device for automatic control of the secondary air damper for heat recovery coking according to claim 1, characterized in that, The heat insulation plate is composed of a main support plate and a reinforcing heat insulation plate fixedly arranged on the inner and outer sides of the main support plate.

5. The guard device for automatic control of the secondary air damper for heat recovery coking according to claim 4, characterized in that, The main support plate is made of steel plate or heat insulation gypsum board material.

6. The guard device for automatic control of the secondary air damper for heat recovery coking according to claim 4, characterized in that The reinforcing heat insulation plate is made of foamed aluminum material.

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