High-temperature flue gas butterfly valve

Abstract

A high-temperature flue gas butterfly valve belongs to the technical field of valves and comprises a bottom cover, a graphite spiral-wound gasket, a split ring, a lower shaft sleeve, a valve body, a sliding bearing, a lower valve rod, a butterfly plate, an upper valve rod, an upper shaft sleeve, packing, a graphite ring, a spacer ring, a supporting ring, a lining, a packing pressing sleeve, a packing pressing plate, a support, a key, a shaft check ring and an executing mechanism. A bottom cover, a graphite spiral-wound gasket, a split ring, a lower shaft sleeve, a valve body, a sliding bearing, a lower valve rod, a butterfly plate, an upper valve rod, an upper shaft sleeve, packing, a graphite ring, a spacer ring, a supporting ring, a lining, a packing pressing sleeve, a packing pressing plate, a support, a key and a shaft check ring are installed together. The risk that the surface of the valve rod is scratched is reduced, the torque of opening and closing operation can be reduced, normal operation of the valve is guaranteed, and the service life of the valve is prolonged; the risk of medium leakage can be reduced; the butterfly plate and the valve rod are connected through a spline, the bearing capacity is high, transmission is stable, durability is good, the butterfly valve is more efficient in the manufacturing and installing process, and product safety and reliability are improved.

Description

Technical Field

[0001] The invention relates to the technical field of valves, in particular to a high-temperature flue gas butterfly valve. Background Art

[0002] Flue gas butterfly valve is a key equipment designed for industrial flue gas treatment system. It has the advantages of small flow resistance, strong flow capacity, rapid opening and closing, strong applicability and high temperature resistance. Therefore, it is widely used in ventilation, environmental protection engineering, flue gas treatment and other pipeline systems in the petroleum, chemical, electric power, steel, pharmaceutical and other industries. In these applications, flue gas butterfly valve plays a vital role to ensure the normal operation of the pipeline system and the effective flow control of the medium.

[0003] The general structure of the existing flue gas butterfly valve includes a valve body, a butterfly plate, a valve stem and a manual or electric or pneumatic drive mechanism. When working, the drive mechanism drives the butterfly plate to rotate through the valve stem, and then adjusts the flow rate of the medium flowing through the valve body (including closing). Although the existing flue gas butterfly valve meets the needs of controlling the medium flow to a certain extent, it is limited by the structure and still has the following defects in use. (1) When the grease in the bearing between the valve stem and the fixed part of the upper end of the valve body is insufficient, the staff needs to manually disassemble the bearing (sliding bearing) and the valve stem, and then inject grease into the bearing. The complicated disassembly process is not conducive to the maintenance and replacement of the valve, and will also cause relatively low work efficiency. (2) The butterfly plate and the valve stem are fixedly connected by keyways or pins. Under the influence of high-temperature media, the keyways or pins and other parts may fall off or loosen. In addition, after the flue gas butterfly valve has been used for a long time, the installation structure of the valve stem and the bearing is not tightly sealed, and the external granular medium can easily enter the contact surface between the sliding bearing and the valve stem, causing the valve stem to get stuck and scratch the surface of the valve stem, which seriously reduces the service life of the flue gas butterfly valve. In summary, due to the above defects, the existing flue gas butterfly valves limit their application and reliability under complex working conditions. It is particularly necessary to provide a flue gas butterfly valve that can work stably and is easy to maintain under various working conditions. Summary of the invention

[0004] In order to overcome the drawbacks of the existing flue gas butterfly valves as described in the background technology due to structural limitations, the present invention provides a high-temperature flue gas butterfly valve with a compact structure, high temperature resistance, wear resistance, easy addition of lubricating grease, good sealing performance, and can effectively avoid the problem of valve stem jamming caused by the erosion of sliding bearings by external particulate media. It is easier and more reliable to assemble and maintain, which brings convenience to the staff in disassembly and maintenance, and ensures that the equipment can work reliably and stably.

[0005] The technical solution adopted by the present invention to solve its technical problem is: A high-temperature flue gas butterfly valve comprises a bottom cover, a graphite spiral wound gasket, a split ring, a lower shaft sleeve, a valve body, a sliding bearing, a lower valve stem, a butterfly plate, an upper valve stem, an upper shaft sleeve, a packing, a graphite ring, a spacer ring, a support ring, a bushing, a packing gland, a packing plate, a bracket, a key, a shaft retaining ring, and an actuator. The lower end of the valve body is fixedly mounted with a lower fixed seat, the bottom cover is fixedly mounted on the outer lower end of the lower fixed seat, the graphite spiral wound gasket is fixedly mounted between the upper end of the bottom cover and the lower end of the lower fixed seat, the first sliding bearing, the outer side of the lower shaft sleeve They are fixedly installed in the lower fixed seat respectively, the upper end of the lower valve stem and the lower end of the butterfly plate are fixedly installed together, the lower end of the lower valve stem is rotatably installed in the first sliding bearing and the lower sleeve, the split ring is rotated and sleeved on the lower bottom end of the lower valve stem, and a lower purge hole is provided on the side of the lower fixed seat between the lower end of the first sliding bearing and the lower sleeve; a mounting seat is fixedly installed on the upper part of the butterfly plate, and a spline groove is provided on the inner side of the mounting seat, an upper fixed seat is fixedly installed on the outer side of the upper end of the valve body, and the lower end of the second sliding bearing is fixedly installed on the lower end of the upper fixed seat. The upper shaft sleeve, support ring, and outer side of the bushing are fixedly installed on the inner side of the upper fixed seat respectively; the first graphite ring, the spacer ring, and the outer side of the second graphite ring are fixedly installed on the inner side of the support ring respectively; the packing is installed on the inner side of the bushing; the packing pressing sleeve is sleeved on the upper end of the bushing; the upper end of the packing pressing plate is fixedly installed on the outer upper end of the bushing; the upper valve stem is rotatably sleeved in the packing pressing plate, the packing pressing sleeve, the second graphite ring, the spacer ring, the first graphite ring, the upper shaft sleeve, and the second sliding bearing; the lower end of the upper valve stem has a spline, and the spline at the lower end of the upper valve stem is fixed The bracket is fixedly installed in the spline groove of the upper fixed seat; the upper sleeve has an upper purge channel, and grease injection ports are distributed on the outside of the spacer ring; the lower side end of the bracket is fixedly installed on the outer side of the upper end of the upper fixed seat, the transmission shaft of the actuator and the top end of the upper valve stem are fixedly installed together, and multiple keys are installed between the upper end of the upper valve stem and the transmission shaft of the actuator. The upper side end of the bracket is fixedly installed on the outside of the lower end of the actuator housing, and the upper valve stem is located at the lower end of the actuator. There is an annular ring, and the shaft is fixedly installed in the annular ring with the inner side of the retaining ring.

[0006] Furthermore, the outer diameter of the split ring is larger than the outer diameters of the lower valve stem and the lower shaft sleeve, and the inner diameter is smaller than the outer diameter of the lower shaft sleeve.

[0007] Furthermore, the outer diameter of the shaft retaining ring is larger than the inner diameter of the shaft hole at the upper side end of the bracket, and the lower end is spaced apart from the upper side end of the bracket.

[0008] Furthermore, the graphite ring is formed by weaving a combination of stainless steel wire and flexible graphite braided filler.

[0009] Furthermore, the inner side of the first sliding bearing and the outer side of the lower valve stem are in a contact rotation structure.

[0010] Furthermore, the inner side of the graphite filler and the upper valve stem are in a rotational contact fitting structure, and the inner side of the second sliding bearing and the outer side of the upper valve stem are in a contact rotation structure.

[0011] Furthermore, the transmission shaft of the actuator is one of manually rotated and mechanically driven.

[0012] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The present invention arranges flexible graphite packing + spacer ring on the valve stem and the valve body. The flexible graphite packing fits the valve stem surface to play a sealing and lubricating role (and has a grease injection port), which can reduce the friction between the valve stem and the valve body during opening and closing, greatly reduce the risk of the valve stem surface being scratched, make the valve stem seal reliable for a long time, and also play a guiding role. In this way, the performance of the valve sealing packing can be greatly improved, and the risk of process medium leakage can be reduced. At the same time, due to the purge port, air can be blown into the shaft sleeve to blow impurities in the conveying medium into the flow channel (pipeline), further reducing the risk of the valve stem surface being scratched. Risk; (2) By setting the shaft ends used in conjunction with the sliding bearings on the upper and lower valve stems, the valve stem can effectively reduce the friction with the contact surface of the valve body during the opening or closing process, reduce the torque of the opening and closing operation, ensure the normal operation of the valve, and extend the service life of the valve; (3) The inner body of the valve body is welded with a sealing cone surface, and the sealing cone surface is hardened with cemented carbide, which enhances the wear resistance and impact resistance, extends the service life, and reduces the risk of medium leakage; (4) The butterfly plate and the valve stem are connected by splines, which have strong load-bearing capacity, stable transmission, and good durability, making the butterfly valve more efficient during the manufacturing and installation process, and improving the safety and reliability of the product. In summary, the present invention has good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is an overall cross-sectional view of the present invention.

[0014] Figure 2 , 3 4 is a schematic diagram of a partially enlarged structure of the invention. DETAILED DESCRIPTION

[0015] Figure 1 , 2As shown in Figures 3 and 4, a high-temperature flue gas butterfly valve comprises a bottom cover 1, a flexible graphite spiral wound gasket 3, a split ring 4, a lower shaft sleeve 5, a valve body 6, a sliding bearing 2, a lower valve stem 7, a butterfly plate 8, an upper valve stem 9, an upper shaft sleeve 10, a metal wire and flexible graphite braided packing 11, a flexible graphite ring 27, a spacer ring 12, a support ring 13, a bushing 14, a packing gland 15, a packing plate 16, bolts and nuts 17, a disc spring 18, a bracket 19, a key 20, a shaft retaining ring 21, an elastic sealing ring 22, and an actuator 23. A hollow lower fixing seat communicating with the interior of the valve body 6 is installed outside the middle of the lower end thereof, and the upper end of the bottom cover 1 is fixed and sealed on the lower fixing seat by bolts and nuts. At the outer lower end, a hollow graphite wound gasket 3 is fixedly installed between the upper end of the bottom cover and the lower end of the lower fixed seat. The first sliding bearing 2 and the outer side of the lower sleeve 5 are fixedly installed at the upper and lower ends of the lower fixed seat respectively. The upper end of the lower valve stem 7 and the middle part of the lower end of the butterfly plate 8 are fixedly installed together. The lower end of the lower valve stem 7 is rotatably installed in the first sliding bearing 2 and the lower sleeve 5. The split ring 4 is turned to be sleeved on the lower bottom end of the lower valve stem 7. There is a lower purge hole on both sides of the lower fixed seat between the lower end of the first sliding bearing 2 and the lower sleeve 5. A lower air inlet pipe 24 that communicates with the inside is fixedly installed on the left outer side of the lower purge hole (the outer side can be connected to the exhaust pipe of the air compressor, and the air compressor valve is opened to compress the air into the lower valve stem 7). The first sliding bearing 2 is inserted between the lower end of the first sliding bearing 2 and the lower sleeve 5, and the impurities in the conveying medium are blown into the flow channel (pipeline), reducing the risk of scratches on the surface of the lower valve stem 7, etc.); the butterfly plate 8 is fixedly installed with a mounting seat with an open structure at the upper end in the middle, and the inner side of the mounting seat has a spline notch 25. A hollow upper fixed seat 26 that communicates with the interior is installed outside the middle of the upper end of the valve body 6. The lower end of the second sliding bearing 2 is fixedly installed at the lower end of the upper fixed seat 26. The upper sleeve 10, the support ring 13, and the outer side of the bushing 14 are respectively fixedly installed at the inner middle and upper end of the upper fixed seat 26 from bottom to top. The first graphite ring 27, the spacer ring 12, and the second graphite ring 27 The outer side is fixedly installed on the inner side of the support ring 13 from bottom to top, the metal wire and flexible graphite braided packing 11 are installed on the inner side of the bushing 14, the packing sleeve 15 is sleeved on the inner upper end of the bushing 14, the upper side end of the packing pressure plate 16 is fixedly installed on the outer upper end of the bushing 14 and located on the upper part of the packing sleeve 15 through the bolts and nuts 17 (the disc spring 18 is located at the lower end of the bolts 17), and the upper valve stem 12 is rotated from top to bottom and sleeved in the packing pressure plate 16, the packing sleeve 15, the second graphite ring 27, the spacer ring, the first graphite ring 27, the upper shaft sleeve 10, and the second sliding bearing 2, the lower end of the upper valve stem 9 has a spline, and the spline tight sleeve at the lower end of the upper valve stem 9 is fixedly installed in the spline groove 25 of the upper fixed seat;An upper purge channel is distributed in an annular manner in the middle of the upper sleeve, an upper purge hole is provided on the upper fixed seat at the left and right ends of the upper purge channel respectively, an opening is provided on the left and right ends of the upper purge hole at the side ends of the upper purge channel respectively, an upper air inlet pipe 28 communicating with the inside is installed in the middle of the outer side of the left opening (the outer side can be connected to the air compressor and exhaust pipe, the air machine valve is opened, and the compressed air enters between the second sliding bearing 2 and the upper sleeve 10, and the impurities in the conveying medium are blown into the flow channel (pipeline), reducing the wear probability of the upper valve stem 9 and the upper sleeve 10, etc.), an inner concave grease injection port is distributed in an annular manner on the outer side of the spacer ring, and a support ring and a left and right end of the upper fixed seat are provided at the left and right sides of the grease injection port respectively. The left opening has a grease injection tube 29 in communication with the inside thereof (a grease injection tube can be used to inject lubricating grease into the corresponding parts such as the upper valve stem through a grease gun); the lower side end of the bracket 19 is fixedly installed on the outer side of the upper end of the upper fixed seat 26, the transmission shaft of the actuator 23 and the upper end of the upper valve stem 9 are fixedly installed together, and a plurality of keys 20 (fixed limit function) are installed between the upper end of the upper valve stem 9 and the transmission shaft of the actuator 23, the upper side end of the bracket 19 is fixedly installed outside the middle of the lower end of the housing of the actuator 23, the upper valve stem 9 is located at the lower end of the actuator and has an inwardly concave annular ring, the inner side of the shaft retaining ring 21 is fixedly installed in the annular ring, and the upper side end of the bracket 19 is located at the lower side of the shaft retaining ring 21. The disc spring 18 is located between the packing gland 15 and the packing plate 16. ;

[0016] Figure 1 , 2 As shown in , 3, and 4, the outer diameter of the split ring 4 is larger than the outer diameter of the lower valve stem 7 and the lower shaft sleeve 5, and the inner diameter is smaller than the outer diameter of the lower shaft sleeve 5. The outer diameter of the shaft retaining ring 21 is larger than the inner diameter of the shaft hole in the middle of the upper side end of the bracket 19, and the lower end is spaced from the upper side end of the bracket 19. The graphite ring 27 is a combination of stainless steel wire and flexible graphite braided packing. The inner side of the first sliding bearing 5 and the outer side of the lower valve stem 7 are in a contact rotation structure.

[0017] The inner side of the graphite packing 11 and the upper valve stem 9 are in a rotating contact matching structure, and the inner side of the second sliding bearing 2 and the outer side of the upper valve stem 9 are in a contact rotating structure. The transmission shaft of the actuator 23 is driven by manual rotation or mechanical power (such as motor, pneumatic motor, etc.). The inner body of the valve body 6 is welded with a sealing cone surface, and the sealing cone surface has hard alloy and is hardened. Figure 1 , 2As shown in 3 and 4, before the present invention is used, the left and right ends of the valve body 6 are respectively connected to the medium output pipeline and the medium input end of the next process production equipment through pipelines, and the two sides of the fixed frame of the servo mechanism are fixedly installed in relevant positions; when in use, the transmission shaft of the actuator drives the butterfly plate 8 to rotate through the upper valve stem 9, and the lower valve stem 7 rotates along the lower shaft sleeve 5, etc., thereby adjusting the flow rate of the medium flowing through the valve body (including closing). The present invention has the following advantages. (1) The material of the upper valve stem 9 and the lower valve stem 7 is made of high-performance materials that are resistant to high temperature and corrosion, which enhances its service life and stability in high temperature and corrosive environments. (2) A plurality of protruding splines are arranged at the bottom of the upper valve stem 9, and corresponding notches 25 are arranged on the butterfly plate, and the splines and notches are closely matched. Since the butterfly plate and the valve stem are connected by splines, the separation and combination of the two are more convenient, and the installation is also more stable, with strong bearing capacity, stable transmission, and good durability, making the butterfly valve more efficient in the manufacturing and installation process, and improving the safety and reliability of the product. (3) A keyway is provided at the top of the upper valve stem to facilitate connection with external transmission equipment. A shaft retaining ring 21 (limiting function) is provided at the top of the upper valve stem, which can form an anti-flying structure with the bracket 19 to prevent the upper valve stem from being pushed up due to excessive pressure in the flow channel and damaging the actuator. (4) Stepped surfaces (upper fixed seat and lower fixed seat) are provided at the upper and lower parts of both ends of the valve body 5, and sliding bearings 2 are provided between the step holes at both ends of the valve body and the valve stem. Both sliding bearings 2 are installed on the outside of the valve stem, which can support, limit and guide the upper and lower valve stems. (5) The flexible graphite packing is tightly attached to the inner wall of the support ring and fits with the surface of the valve stem to achieve sealing. At the same time, the flexible graphite packing plays a guiding role. An annular groove is arranged on the spacer ring, and a grease adding device is arranged on the surface of the support ring. The outlet hole of the grease adding device is connected with the annular groove, which is convenient for adding grease. The structure is convenient and simple to operate, and the lubricating grease in the sliding bearing is prevented from leaking. The friction between the valve stem and the valve body during the opening and closing process of the valve stem is reduced, which greatly reduces the risk of the valve stem surface being scratched, making the valve stem seal reliable for a long time. It can also play a guiding role, which can greatly improve the performance of the valve sealing packing and reduce the risk of leakage of the process medium. At the same time, due to the purge port, air can be blown into the shaft sleeve to blow impurities in the conveying medium into the flow channel (pipeline), further reducing the risk of scratching the valve stem surface. (6) A bushing is provided on the valve body. A flexible graphite packing, a packing sleeve and a packing pressure plate are provided between the bushing and the upper valve stem. An elastic sealing ring is provided between the bushing and the valve body to prevent leakage of lubricating grease. The bushing is fastened to the top end face of the valve body with bolts and nuts to prevent movement and enhance its stability. At the same time, the bushing acts as a guide to prevent external media and dust from entering the valve body.(7) The inner body of the valve body is welded with a sealing cone surface, which is coated with carbide and hardened to enhance its wear resistance and impact resistance, reduce the risk of leakage and extend its service life; the arc side wall of the butterfly plate is machined with a sealing cone surface, which is welded with carbide and wedged with the sealing surface of the valve body; a spiral wound gasket is provided between the valve body and the bottom cover to improve the sealing performance of the device and prevent high-temperature flue gas leakage. By setting the shaft ends used in conjunction with sliding bearings on the upper and lower valve stems, the valve stem can effectively reduce the friction with the contact surface of the valve body during opening or closing, reduce the torque of the opening and closing operation, ensure the normal operation of the valve, and extend the service life of the valve body.

[0018] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It is obvious to those skilled in the art that the present invention is limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes that fall within the meaning and scope of the equivalent elements of the claims are included in the present invention.

[0019] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode includes only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. High temperature flue gas butterfly valve, including bottom cover, graphite spiral wound gasket, split ring, lower shaft sleeve, valve body, sliding bearing, lower valve stem, butterfly plate, upper valve stem, upper shaft sleeve, packing, graphite ring, spacer ring, support ring, bushing, packing gland, packing plate, bracket, key, shaft retaining ring, actuator, characterized in that: The lower end of the valve body is fixedly installed with a lower fixed seat, the bottom cover is fixedly installed on the outer lower end of the lower fixed seat, the graphite wound gasket is fixedly installed between the upper end of the bottom cover and the lower end of the lower fixed seat, the first sliding bearing and the outer side of the lower sleeve are respectively fixedly installed in the lower fixed seat, the upper end of the lower valve stem and the lower end of the butterfly plate are fixedly installed together, the lower end of the lower valve stem is rotatably installed in the first sliding bearing and the lower sleeve, the split ring is rotated to be sleeved on the lower bottom end of the lower valve stem, and the side of the lower fixed seat between the lower end of the first sliding bearing and the lower sleeve is provided with a lower purge hole; the upper part of the butterfly plate is fixedly installed with a mounting seat, the inner side of the mounting seat has a spline groove, the upper end of the valve body is fixedly installed with an upper fixed seat, the lower end of the second sliding bearing is fixedly installed on the inner lower end of the upper fixed seat, the upper sleeve, the support ring, and the outer sides of the bushing are respectively fixedly installed on the inner side of the upper fixed seat, and the outer sides of the first graphite ring, the spacer ring and the second graphite ring are respectively It is fixedly installed on the inner side of the support ring, the packing is installed on the inner side of the bushing, the packing pressure sleeve is sleeved on the upper end of the bushing, the upper end of the packing pressure plate is fixedly installed on the outer upper end of the bushing, the upper valve stem rotates in the packing pressure plate, the packing pressure sleeve, the second graphite ring, the spacer ring, the first graphite ring, the upper shaft sleeve, and the second sliding bearing. The lower end of the upper valve stem is provided with a spline, and the spline at the lower end of the upper valve stem is fixedly installed in the spline groove of the upper fixed seat; the upper shaft sleeve has an upper purge channel, and grease injection ports are distributed on the outside of the spacer ring; the lower side end of the bracket is fixedly installed on the outer side of the upper end of the upper fixed seat, the transmission shaft of the actuator and the top end of the upper valve stem are fixedly installed together, and multiple keys are installed between the upper end of the upper valve stem and the transmission shaft of the actuator, the upper side end of the bracket is fixedly installed on the outside of the lower end of the actuator housing, the upper valve stem is provided with an annular ring at the lower end of the actuator, and the shaft is fixedly installed in the annular ring with the inner side of the retaining ring.

2. The high temperature flue gas butterfly valve according to claim 1, characterized in that: The outer diameter of the split ring is larger than the outer diameters of the lower valve stem and the lower shaft sleeve, and the inner diameter is smaller than the outer diameter of the lower shaft sleeve.

3. The high temperature flue gas butterfly valve according to claim 1, characterized in that: The outer diameter of the shaft retaining ring is larger than the inner diameter of the shaft hole at the upper side end of the bracket, and the lower end is spaced apart from the upper side end of the bracket.

4. The high temperature flue gas butterfly valve according to claim 1, characterized in that: Graphite rings are made of stainless steel wire and flexible graphite braided packing.

5. The high temperature flue gas butterfly valve according to claim 1, characterized in that: The inner side of the first sliding bearing and the outer side of the lower valve stem are in a contact rotation structure.

6. The high temperature flue gas butterfly valve according to claim 1, characterized in that: The inner side of the graphite packing and the upper valve stem are in a rotational contact fitting structure, and the inner side of the second sliding bearing and the outer side of the upper valve stem are in a contact rotation structure.

7. The high temperature flue gas butterfly valve according to claim 1, characterized in that: The transmission shaft of the actuator is one of manual rotation and mechanical power drive.

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