Phthalic anhydride flaker

Abstract

The utility model discloses a phthalic anhydride flaker in the technical field of chemical equipment, which comprises a box body, a rotary drum is arranged in the box body, the front end and the rear end of the rotary drum are connected with connecting shafts, the ends, deviating from the rotary drum, of the two groups of connecting shafts extend out of the box body, a water cooling mechanism is arranged between the rotary drum and the connecting shafts, and a feed hopper is arranged at the left end of the top of the box body. A hydraulic cylinder is installed on the right side of the box, a scraper is installed at the output end of the hydraulic cylinder, a mounting base is installed at the end, close to the feeding hopper, of the top of the box, ventilation holes are formed in the top of the mounting base, transmission rods are connected to the two ends of the inner top wall of the mounting base, and fan blades are installed at the bottoms of the two transmission rods. According to the flaker, the inner wall of the rotary drum is subjected to water cooling through the arrangement of the water cooling mechanism, and meanwhile, the outer wall of the rotary drum is subjected to air cooling through the matched arrangement of the mounting seat, the fan blades, the transmission rod, the transmission mechanism and the ventilation holes, so that a liquid phthalic anhydride material on the outer wall of the rotary drum is quickly crystallized, and the working efficiency of the flaker is improved.

Description

Technical Field

[0001] This utility model relates to the technical field of chemical equipment, and in particular to a phthalic anhydride flake machine. Background Technology

[0002] Phthalic anhydride, also known as phthalic anhydride, is an important basic organic chemical raw material and the largest producer and consumer among the four major acid anhydrides. Approximately 60% of it is used in the manufacture of polyvinyl chloride plasticizers, 30% in polyester resins and alkyd resins, and the remaining 10% in industries such as paints, dyes, pharmaceuticals, and pesticides. The production of phthalic anhydride involves a crystallization process, which requires the obtained product solution to crystallize into a plate / layer structure in order to obtain the product and continue production. Typically, a plate-forming machine is used to process this plate / layer crystallization.

[0003] Patent publication number CN208944053U discloses a phthalic anhydride flake cutting machine with controllable cutting thickness, including an outer shell, a blade, and a metal frame. An L-shaped metal rod is welded to the upper surface of the mounting bracket fixed at the top right side of the outer shell. An infrared emitter and a cooler are installed sequentially from left to right on the lower outer surface of the L-shaped metal rod. The infrared emitter is directly opposite to the infrared receiver set on the upper surface of the material tray. A rotary motor is installed inside the roller set above the outer shell. A concave groove is fixed to the left side of the electric telescopic rod fixed at the left end of the mounting bracket. The concave groove is engaged with the long metal rod welded to the right side of the blade. This invention solves the problems of uncontrolled sheet shape during production, failure to meet production requirements, and cumbersome process of removing the entire blade holder when the blade needs to be replaced due to damage by setting up an infrared receiver, infrared transmitter, concave groove, blade, metal rod, fastening bolt, alarm, and controller. However, the above device uses a cooler to cool the roller, which is a single cooling method. In addition, the L-shaped metal rod is in an open state, which makes the cooling easily spread and the cooling effect is not obvious, thereby reducing the sheet formation efficiency of the device. Utility Model Content

[0004] To address the issue that the aforementioned device uses a cooler to cool the drum, resulting in a single cooling method and the L-shaped metal rod being in an open state, causing the cooling to easily disperse and the cooling effect to be insignificant, thus reducing the device's flake formation efficiency, this utility model provides a phthalic anhydride flake forming machine.

[0005] This utility model provides a phthalic anhydride flake-forming machine, which adopts the following technical solution:

[0006] A phthalic anhydride flake forming machine includes a housing, inside which a rotating drum is installed. Connecting shafts are connected to both the front and rear ends of the rotating drum. The ends of two sets of connecting shafts opposite to the rotating drum extend out of the housing. A drive mechanism is provided between the front connecting shaft and the housing. A water-cooling mechanism is provided between the rotating drum and the connecting shafts. A feed hopper is installed at the left end of the top of the housing. A hydraulic cylinder is installed on the right side of the housing. A scraper is installed at the output end of the hydraulic cylinder. A mounting base is installed at the top of the housing near the feed hopper. A ventilation hole is provided at the top of the mounting base. Transmission rods are connected to both ends of the inner top wall of the mounting base. Fan blades are installed at the bottom of both sets of transmission rods. A transmission mechanism is provided at the top of both sets of transmission rods.

[0007] By adopting the above technical solution, liquid phthalic anhydride material flows from the feed hopper onto the outer circumferential surface of the drum. The drive mechanism drives the connecting shaft to rotate, which in turn drives the drum to rotate. When the material on the drum passes the mounting seat, the transmission mechanism drives two sets of transmission rods and fan blades to rotate synchronously, which air-cools the outer wall of the drum. At the same time, the water-cooling mechanism cools the inner wall of the drum, thereby directly and rapidly cooling the liquid phthalic anhydride material on the surface of the drum. This improves the quality of phthalic anhydride flakes. The hydraulic cylinder extends and drives the scraper to move to the left, so that the scraper fits against the outer wall of the drum, thereby peeling the phthalic anhydride flakes off the outer wall of the drum.

[0008] Optionally, a receiving trough is installed at the left end of the bottom wall of the box, and a collecting trough is installed at the right end of the bottom wall of the box. Both the receiving trough and the collecting trough are equipped with sliding mechanisms at their bottoms.

[0009] By adopting the above technical solution, excess liquid phthalic anhydride is collected through a receiving tank, and the detached phthalic anhydride flakes are collected through a collection tank.

[0010] Optionally, the sliding mechanism includes a slider, which is installed at the bottom of the receiving trough and the collecting trough. The inner bottom wall of the box is provided with a sliding groove, which is slidably connected to the slider.

[0011] By adopting the above technical solution, the material receiving trough and the material collecting trough can be easily removed from the inside of the box by the sliding cooperation of the chute and the slider, and the material inside the receiving trough and the clumps inside the collecting trough can be removed.

[0012] Optionally, the drive mechanism includes a support plate, which is installed on the upper part of the outer side of the housing. A drive motor is installed on the side of the support plate near the housing. An active gear plate is installed on the power output end of the drive motor. A driven gear plate is meshed on the left end of the active gear plate, and the driven gear plate is sleeved on the outer side of the front connecting shaft.

[0013] By adopting the above technical solution, when the drive motor is working, it drives the active gear disk to rotate, and the rotation of the active gear disk drives the driven gear disk to rotate, which in turn drives the drum to rotate through the connecting shaft.

[0014] Optionally, a door is hinged to the housing below the drive mechanism.

[0015] By adopting the above technical solution, it is convenient to open the door to connect the material trough and collection trough for disassembly and assembly.

[0016] Optionally, the transmission mechanism includes a stepper motor, which is mounted on the top of the housing. A first transmission shaft is mounted on the power output end of the stepper motor. A first transmission gear is mounted on the top of the first transmission shaft. Second transmission gears are meshed on both sides of the first transmission gear. The bottoms of the two sets of second transmission gears are connected to second transmission shafts. The bottoms of the two sets of second transmission shafts are respectively fixedly connected to the tops of the two sets of transmission rods.

[0017] By adopting the above technical solution, when the stepper motor is working, it drives the first transmission gear to rotate through the first transmission shaft, the first transmission gear to rotate, the second transmission gear to rotate, and the second transmission shaft to rotate, thereby driving the two sets of transmission rods to rotate synchronously.

[0018] Optionally, a baffle is provided at the bottom of the feed hopper, and a translation mechanism is provided between the baffle and the box body. The translation mechanism includes a vertical plate, which is installed on the top wall of the box body near the feed hopper. A one-way threaded rod is connected between the vertical plate and the inner wall of the box body. A forward and reverse motor for driving the one-way threaded rod to rotate is installed at the upper left side of the box body. A movable sleeve is screwed to the outer wall of the one-way threaded rod. A connecting block is connected to the bottom of the movable sleeve. A limit rod is connected to the bottom of the connecting block. The left end of the limit rod extends out of the box body, and the right end of the limit rod is fixedly connected to the left end of the baffle.

[0019] By adopting the above technical solution, when the forward and reverse motors are working, they drive the one-way threaded rod to rotate. The rotation of the one-way threaded rod drives the movable sleeve to move left and right. When the movable sleeve moves, it drives the limit rod to move left and right through the connecting block, which in turn drives the baffle to move horizontally at the bottom of the feed hopper, making it convenient to adjust the size of the feed hopper inlet.

[0020] Optionally, the water cooling mechanism includes several annular tubes, which are installed at equal intervals inside the drum. Several straight tubes connect adjacent annular tubes. The outer walls of the straight tubes and annular tubes are in close contact with the inner wall of the drum. A water inlet pipe is connected to one side of the left annular tube, and a water outlet pipe is connected to one side of the right annular tube. The ends of the water inlet pipe and the water outlet pipe that are away from the annular tubes pass through a connecting shaft and are fitted with rotary joints.

[0021] By adopting the above technical solution, the rotary joint is connected to an external water pipe, and cooling water is introduced through the inlet pipe. The heat on the drum is carried away through the straight pipe and the annular pipe and discharged through the outlet pipe, thereby enabling water cooling of the liquid phthalic anhydride material on the surface of the drum and improving the quality of phthalic anhydride flakes.

[0022] In summary, this utility model has at least one of the following beneficial effects:

[0023] The water-cooling mechanism cools the inner wall of the drum, while the mounting base, fan blades, transmission rod, transmission mechanism, and ventilation holes provide air cooling for the outer wall of the drum. This allows the liquid phthalic anhydride material on the outer wall of the drum to crystallize rapidly, improving the working efficiency of the flake-forming machine.

[0024] By combining the baffle and the translation mechanism, the translation mechanism drives the baffle to move laterally at the bottom of the feed hopper when it is working, thereby adjusting the size of the feed inlet at the bottom of the feed hopper and thus controlling the thickness of the phthalic anhydride flakes to meet production requirements. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a cross-sectional structural diagram of the present invention;

[0027] Figure 2 This is a schematic cross-sectional view of the rotating drum of this utility model;

[0028] Figure 3 This is a schematic diagram of the connection structure between the annular pipe and the straight pipe of this utility model;

[0029] Figure 4 This is a front view structural diagram of the present utility model;

[0030] Figure 5 For the present utility model Figure 1 Enlarged structural diagram at point A in the middle.

[0031] In the diagram: 1. Feed hopper; 2. Housing; 3. Drum; 4. Receiving trough; 5. Sliding mechanism; 501. Slide groove; 502. Slider; 6. Collection trough; 7. Hydraulic cylinder; 8. Scraper; 9. Water cooling mechanism; 901. Rotary joint; 902. Water inlet pipe; 903. Straight pipe; 904. Annular pipe; 905. Water outlet pipe; 10. Mounting base; 11. Fan blade; 12. Transmission rod; 13. Transmission mechanism; 1301. Stepper motor; 1302. First transmission shaft; 1303. ... 1304. Second transmission gear; 1305. Second transmission shaft; 14. Ventilation hole; 15. Baffle; 16. Connecting shaft; 17. Drive mechanism; 1701. Driven gear plate; 1702. Driven gear plate; 1703. Support plate; 1704. Drive motor; 18. Door body; 19. Translation mechanism; 1901. Forward and reverse motor; 1902. One-way threaded rod; 1903. Limiting rod; 1904. Movable sleeve; 1905. Connecting block; 1906. Vertical plate. Detailed Implementation

[0032] The following is in conjunction with the appendix Figure 1-5 The present invention will be described in further detail below.

[0033] Please refer to the attached diagram in the instruction manual. Figure 1 This utility model provides an embodiment of a phthalic anhydride flake forming machine, comprising a housing 2, a rotating drum 3 rotatably mounted inside the housing 2, a receiving trough 4 installed at the left end of the inner bottom wall of the housing 2, and a collecting trough 6 installed at the right end of the inner bottom wall of the housing 2. Both the receiving trough 4 and the collecting trough 6 are equipped with sliding mechanisms 5 at their bottoms. Excess liquid phthalic anhydride is collected through the receiving trough 4, and the detached phthalic anhydride flakes are collected through the collecting trough 6.

[0034] Please refer to the attached diagram in the instruction manual. Figure 1 The sliding mechanism 5 includes a slider 502, which is fixedly installed at the bottom of the receiving trough 4 and the collecting trough 6. The inner bottom wall of the housing 2 is provided with a sliding groove 501, which is slidably connected to the slider 502. Through the sliding engagement of the sliding groove 501 and the slider 502, it is convenient to remove the receiving trough 4 and the collecting trough 6 from the inside of the housing 2 and remove the material inside the receiving trough 4 and the clumps inside the collecting trough 6.

[0035] Please refer to the attached diagram in the instruction manual. Figure 1 and Figure 4The drum 3 is fixedly connected to both its front and rear ends by connecting shafts 16. The ends of the two sets of connecting shafts 16 facing away from the drum 3 extend out of the housing 2. A drive mechanism 17 is provided between the front connecting shaft 16 and the housing 2. The drive mechanism 17 includes a support plate 1703, which is mounted on the upper outer side of the housing 2. A drive motor 1704 is mounted on the side of the support plate 1703 closest to the housing 2. A drive gear 1702 is mounted on the power output end of the drive motor 1704. A driven gear 1701 is meshed with the left end of the drive gear 1702, and the driven gear 1701 is sleeved on the outer side of the front connecting shaft 16. When the drive motor 1704 operates, it drives the drive gear 1702 to rotate, which in turn drives the driven gear 1701 to rotate, thereby driving the drum 3 to rotate via the connecting shaft 16. A door 18 is hinged to the housing 2 below the drive mechanism 17. The door 18 is easily opened for disassembly and assembly of the material trough 4 and the collection trough 6.

[0036] Please refer to the attached diagram in the instruction manual. Figure 1 , Figure 2 and Figure 3 A water-cooling mechanism 9 is provided between the drum 3 and the connecting shaft 16. The water-cooling mechanism 9 includes several annular tubes 904, which are installed at equal intervals inside the drum 3. Several straight tubes 903 are fixedly connected between adjacent annular tubes 904. The outer walls of the straight tubes 903 and the annular tubes 904 are in close contact with the inner wall of the drum 3. A water inlet pipe 902 is connected to one side of the left annular tube 904, and a water outlet pipe 905 is connected to one side of the right annular tube 904. The ends of the water inlet pipe 902 and the water outlet pipe 905 opposite to the annular tube 904 pass through the connecting shaft 16 and are equipped with a rotary joint 901. The rotary joint 901 connects to an external water pipe, and cooling water is introduced through the water inlet pipe 902. The heat on the drum 3 is carried away through the straight tubes 903 and the annular tubes 904 and discharged through the water outlet pipe 905. This water-cooling mechanism can cool the liquid phthalic anhydride material on the surface of the drum 3, improving the quality of phthalic anhydride flakes.

[0037] Please refer to the attached diagram in the instruction manual. Figure 1 and Figure 5A feed hopper 1 is installed at the top left end of the box 2. A baffle 15 is provided at the bottom of the feed hopper 1. A translation mechanism 19 is provided between the baffle 15 and the box 2. The translation mechanism 19 includes a vertical plate 1906. The vertical plate 1906 is installed on the top wall of the box 2 near the feed hopper 1. A one-way threaded rod 1902 is rotatably connected between the vertical plate 1906 and the inner wall of the box 2. A forward and reverse motor 1901 for driving the one-way threaded rod 1902 to rotate is installed at the upper left end of the box 2. A movable sleeve 1904 is screwed onto the outer wall of the one-way threaded rod 1902. A connecting block 1905 is connected to the bottom of the movable sleeve 1904. A limit rod 1903 is horizontally connected to the bottom of the connecting block 1905. The left end of the limit rod 1903 extends out of the box 2, and the right end of the limit rod 1903 is fixedly connected to the left end of the baffle 15. When the forward and reverse motor 1901 is working, it drives the one-way threaded rod 1902 to rotate. The rotation of the one-way threaded rod 1902 drives the movable sleeve 1904 to move left and right. When the movable sleeve 1904 moves, it drives the limit rod 1903 to move left and right through the connecting block 1905, which in turn drives the baffle 15 to move horizontally at the bottom of the feed hopper 1, so as to facilitate the adjustment of the size of the feed inlet of the feed hopper 1.

[0038] Please refer to the attached diagram in the instruction manual. Figure 1 and Figure 4 A hydraulic cylinder 7 is installed on the right side of the housing 2. A scraper 8 is installed at the output end of the hydraulic cylinder 7. A mounting base 10 is installed at the top of the housing 2 near the feed hopper 1. A ventilation hole 14 is opened at the top of the mounting base 10. Both ends of the inner top wall of the mounting base 10 are connected to transmission rods 12. Fan blades 11 are installed at the bottom of the two sets of transmission rods 12. A transmission mechanism 13 is set at the top of the two sets of transmission rods 12. The transmission mechanism 13 includes a stepper motor 1301. The stepper motor 1301 is installed at the top of the housing 2. A first transmission shaft 1302 is installed at the power output end of the stepper motor 1301. A first transmission gear 1303 is installed at the top of the first transmission shaft 1302. Second transmission gears 1304 are meshed on both sides of the first transmission gear 1303. A second transmission shaft 1305 is connected to the bottom of the two sets of second transmission gears 1304. The bottom of the two sets of second transmission shafts 1305 is fixedly connected to the top of the two sets of transmission rods 12 respectively. When the stepper motor 1301 is working, it drives the first transmission gear 1303 to rotate through the first transmission shaft 1302. The rotation of the first transmission gear 1303 drives the second transmission gear 1304 to rotate, and the rotation of the second transmission gear 1304 drives the second transmission shaft 1305 to rotate, thereby driving the two sets of transmission rods 12 to rotate synchronously.

[0039] Working principle: When in use, the operator pours the prepared hot-molten liquid phthalic anhydride material into the feed hopper 1, which flows through the feed inlet onto the outer circumferential surface of the drum 3. The drive motor 1704 is started. When the drive motor 1704 is working, it drives the active gear disk 1702 to rotate. The rotation of the active gear disk 1702 drives the driven gear disk 1701 to rotate, which in turn drives the connecting shaft 16 to rotate, thereby making the drum 3 rotate clockwise.

[0040] Next, the stepper motor 1301 is turned on. When the stepper motor 1301 is working, it drives the first transmission gear 1303 to rotate through the first transmission shaft 1302. The rotation of the first transmission gear 1303 drives the second transmission gear 1304 to rotate, and the rotation of the second transmission gear 1304 drives the second transmission shaft 1305 to rotate, thereby driving the two sets of transmission rods 12 and fan blades 11 to rotate synchronously. When the material on the drum 3 passes the mounting base 10, the outer wall of the drum 3 is cooled by air. At the same time, it is connected to an external water pipe through the rotary joint 901. Cooling water is introduced through the water inlet pipe 902. The heat on the drum 3 is carried away through the straight pipe 903 and the annular pipe 904 and discharged through the water outlet pipe 905. By adopting a combination of air cooling and water cooling, the liquid phthalic anhydride material on the surface of the drum 3 can be directly and quickly cooled, thus improving the quality of phthalic anhydride flakes.

[0041] Simultaneously, the hydraulic cylinder 7 is extended, which drives the scraper 8 to move to the left, so that the scraper 8 is in contact with the outer wall of the drum 3. Thus, the phthalic anhydride flakes are peeled off from the outer wall of the drum 3 by the scraper 8 and fall into the collection tank 6 below. Excess liquid material falls into the inside of the receiving tank 4.

[0042] When the rotation speed of the drum 3 is constant, by adjusting the size of the feed inlet at the bottom of the feed hopper 1, the thickness of the liquid phthalic anhydride flowing onto the outer circumferential surface of the drum 3 can be different, thus resulting in different thicknesses of phthalic anhydride flakes. During adjustment, the forward and reverse motor 1901 is turned on. When the forward and reverse motor 1901 is working, it drives the one-way threaded rod 1902 to rotate. The rotation of the one-way threaded rod 1902 drives the movable sleeve 1904 to move left and right. When the movable sleeve 1904 moves, it drives the limiting rod 1903 to move left and right through the connecting block 1905, thereby limiting the movable sleeve 1904. Thus, the baffle 15 can be moved laterally at the bottom of the feed hopper 1 through the limiting rod 1903, which facilitates the adjustment of the size of the feed inlet at the bottom of the feed hopper 1.

[0043] The above are all preferred embodiments of this utility model, and are not intended to limit the scope of protection of this utility model. Therefore, all equivalent changes made to the structure, shape and principle of this utility model should be covered within the scope of protection of this utility model.

Claims

1. A phthalic anhydride flake forming machine, comprising a housing (2), characterized in that: A rotating drum (3) is installed inside the housing (2). Connecting shafts (16) are connected to both the front and rear ends of the rotating drum (3). The ends of the two sets of connecting shafts (16) facing away from the rotating drum (3) extend out of the housing (2). A driving mechanism (17) is provided between the front connecting shaft (16) and the housing (2). A water-cooling mechanism (9) is provided between the rotating drum (3) and the connecting shafts (16). A feed hopper (1) is installed at the left end of the top of the housing (2). The right end of the housing (2)... A hydraulic cylinder (7) is installed on the side, and a scraper (8) is installed at the output end of the hydraulic cylinder (7). A mounting base (10) is installed at the top of the box (2) near the feed hopper (1). A ventilation hole (14) is opened at the top of the mounting base (10). Both ends of the inner top wall of the mounting base (10) are connected to transmission rods (12). Fan blades (11) are installed at the bottom of the two sets of transmission rods (12). A transmission mechanism (13) is provided at the top of the two sets of transmission rods (12).

2. The phthalic anhydride flake-forming machine according to claim 1, characterized in that: A receiving groove (4) is installed on the left end of the bottom wall of the box (2), and a collection groove (6) is installed on the right end of the bottom wall of the box (2). A sliding mechanism (5) is provided at the bottom of both the receiving groove (4) and the collection groove (6).

3. A phthalic anhydride flake-forming machine according to claim 2, characterized in that: The sliding mechanism (5) includes a slider (502), which is installed at the bottom of the receiving trough (4) and the collecting trough (6). The inner bottom wall of the box (2) is provided with a sliding groove (501), which is slidably connected to the slider (502).

4. A phthalic anhydride flake-forming machine according to claim 1, characterized in that: The drive mechanism (17) includes a support plate (1703), which is installed on the upper part of the outer side of the housing (2). A drive motor (1704) is installed on the side of the support plate (1703) near the housing (2). An active gear plate (1702) is installed at the power output end of the drive motor (1704). A driven gear plate (1701) is meshed with the left end of the active gear plate (1702), and the driven gear plate (1701) is sleeved on the outer side of the front connecting shaft (16).

5. A phthalic anhydride flake-forming machine according to claim 1, characterized in that: A door (18) is hinged to the housing (2) below the drive mechanism (17).

6. A phthalic anhydride flake-forming machine according to claim 1, characterized in that: The transmission mechanism (13) includes a stepper motor (1301), which is mounted on the top of the housing (2). A first transmission shaft (1302) is mounted on the power output end of the stepper motor (1301). A first transmission gear (1303) is mounted on the top of the first transmission shaft (1302). A second transmission gear (1304) is meshed on both sides of the first transmission gear (1303). A second transmission shaft (1305) is connected to the bottom of each of the two sets of second transmission gears (1304). The bottom of each of the two sets of second transmission shafts (1305) is fixedly connected to the top of the two sets of transmission rods (12).

7. A phthalic anhydride flake-forming machine according to claim 1, characterized in that: A baffle (15) is provided at the bottom of the feed hopper (1). A translation mechanism (19) is provided between the baffle (15) and the box body (2). The translation mechanism (19) includes a vertical plate (1906). The vertical plate (1906) is installed on the top wall of the box body (2) near the feed hopper (1). A one-way threaded rod (1902) is connected between the vertical plate (1906) and the inner wall of the box body (2). A drive mechanism is installed on the upper left side of the box body (2). A forward and reverse motor (1901) rotates a one-way threaded rod (1902). A movable sleeve (1904) is screwed onto the outer wall of the one-way threaded rod (1902). A connecting block (1905) is connected to the bottom of the movable sleeve (1904). A limiting rod (1903) is connected to the bottom of the connecting block (1905). The left end of the limiting rod (1903) extends out of the housing (2). The right end of the limiting rod (1903) is fixedly connected to the left end of the baffle (15).

8. A phthalic anhydride flake-forming machine according to claim 1, characterized in that: The water cooling mechanism (9) includes several annular tubes (904), which are installed at equal intervals inside the drum (3). Several straight tubes (903) are connected between two adjacent annular tubes (904). The outer walls of the straight tubes (903) and the annular tubes (904) are in close contact with the inner wall of the drum (3). A water inlet pipe (902) is connected to one side of the left annular tube (904), and a water outlet pipe (905) is connected to one side of the right annular tube (904). The ends of the water inlet pipe (902) and the water outlet pipe (905) away from the annular tube (904) both pass through the connecting shaft (16) and are equipped with a rotary joint (901).

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