A gas-liquid two-phase flow shell and tube heat exchanger

Abstract

The present application relates to the field of heat exchangers, and specifically discloses a gas-liquid two-phase flow shell and tube heat exchanger, which includes a shell, a shell cover, a plurality of insulating tubes arranged in the shell, baffles sleeved on the tubes, and tube sheets respectively fixed to the two ends of the tubes, the shell cover and the tubes are connected by flanges, the shell is provided with a hot flow inlet and a hot flow outlet on two opposite sides between the two baffles, a cold flow inlet is provided on the shell cover near one end of the hot flow outlet, and a cold flow outlet is provided on the shell cover near one end of the hot flow inlet, two mutually parallel guide rails are provided on two opposite sides of the inner wall of the tube body, a slide bar is placed on the guide rail, both ends of the guide rail are connected to an external DC power supply, and the electrodes externally connected to the same end of the two guide rails in the same tube body are opposite, a scraper ring is provided on the slide bar that fits the inner wall of the tube body, and a limiter is also provided on the guide rail for limiting the slide bar to move only along the length range of the guide rail. The present application has the effect of facilitating the cleaning of debris on the inner wall of the tube body.

Description

Technical Field

[0001] The present application relates to the field of heat exchangers, and in particular to a gas-liquid two-phase flow shell and tube heat exchanger. Background Art

[0002] Shell and tube heat exchanger, also known as shell and tube heat exchanger, is a partition wall heat exchanger that uses the wall of the tube bundle enclosed in the shell as the heat transfer surface. Shell and tube heat exchanger consists of shell, heat transfer tube bundle, tube sheet, baffle (baffle) and tube box. The shell is mostly cylindrical with tube bundle inside. Both ends of the tube bundle are fixed on the tube sheet for heat exchange. One of the hot and cold fluids flows inside the tube, called tube-side fluid; the other flows outside the tube, called shell-side fluid.

[0003] In actual working conditions, the fluid inside the shell and tube heat exchanger often includes high-temperature steam; gases such as air and nitrogen; liquids such as water and acid and alkali solutions, and the fluid temperature changes greatly during use. Therefore, after long-term use, the inner and outer walls of each tube of the tube bundle of the shell and tube heat exchanger are adhered with a lot of dirt and other debris. At this time, it is necessary to open the can for cleaning. The most commonly used cleaning methods include flushing the inner and outer walls of the tube body with a high-pressure water gun; soaking the inner and outer walls of the tube body with a detergent; poking and knocking on the debris that is tightly adhered to the tube wall of the tube body.

[0004] With respect to the above-mentioned related technologies, the inventors believe that the following defects exist: since the shell is troublesome to disassemble and assemble, many customers neglect to clean it or extend the cleaning cycle, which results in a large amount of debris on the wall of the tube body and the debris adheres tightly; and since the diameter of the tube body is small and the length of the tube body is long, when the inner wall of the tube body is flushed with a high-pressure water gun, the debris tightly adhered to the inner wall of the tube body is difficult to be washed off by the water flow, and when the debris is poked or poked with tools such as wire, the debris at the mouth of the tube body is easier to be removed, and when removing debris deep in the tube body, tools such as wire are too long and easy to bend, which makes it difficult to remove the debris. Summary of the invention

[0005] In order to improve the problem that debris on the inner wall of a tube body is difficult to remove, the present application provides a gas-liquid two-phase flow shell and tube heat exchanger.

[0006] The present application provides a gas-liquid two-phase flow shell and tube heat exchanger adopts the following technical solution:

[0007] A gas-liquid two-phase flow shell and tube heat exchanger, comprising a shell, a shell cover arranged at both ends of the shell, a plurality of tubes arranged in the shell, baffles sleeved on the tubes and tube sheets respectively fixed to both ends of the tubes, the shell cover is fixedly connected to a flange at one end close to the shell, and both ends of the tubes are also fixedly connected to flanges, the shell cover and the tubes are connected through the flanges, the shell is respectively provided with a hot flow inlet and a hot flow outlet on two opposite sides between the two baffles, and a cold flow outlet is provided on the shell cover close to one end of the hot flow outlet inlet, a cold flow outlet is provided on the shell cover near one end of the hot flow inlet, and is characterized in that: two parallel guide rails are arranged on two opposite sides of the inner wall of the tube body, a slide bar is placed on the guide rails, both ends of the guide rails are connected to an external DC power supply, and the electrodes externally connected to the same end of the two guide rails in the same tube body are opposite, a scraper ring is arranged on the slide bar and fits with the inner wall of the tube body, the inner wall of the tube body is insulated, and a limiter is also arranged on the guide rail for limiting the slide bar to move only along the length range of the guide rail.

[0008] By adopting the above technical solution, after the shell and tube heat exchanger is shut down, the staff only needs to energize the power supply at one end of the guide rail. At this time, the two guide rails, the slide rod and the external DC power supply in the tube body form a closed loop, and the direction of the magnetic flux lines of the two guide rails and the slide rod close to the energized power supply side can be obtained according to the flow direction of the current and Ampere's law. Then, the direction of the Ampere force on the slide rod can be obtained by the left-hand rule, that is, when the guide rail is energized, the slide rod is acted upon by the Ampere force and moves on the guide rail, thereby driving the scraper ring to move. The moving scraper ring can scrape off the debris on the inner wall of the tube body and push it away until the slide rod slides to the end of the guide rail and stops moving due to the action of the limiter. At this time, the scraper ring will also move away from the guide rail. The debris scraped off the inner wall of the tube body is pushed out from the pipe mouth of the tube body; when the power of one end of the above-mentioned turned-on guide rail is turned off and the power of the other end is turned on, the slide bar moves in the opposite direction of the above-mentioned moving direction, so that the scraper ring reciprocates in the tube body, effectively improving the cleaning effect of the scraper ring on the inner wall of the tube body, and the cleaning process does not need to open the shell cover and use tools such as high-pressure water guns to clean the inner wall of the tube body, which greatly saves labor costs. Since the above-mentioned cleaning process only needs to be carried out when the shell is not working, the cleaning operation can be started more conveniently and timely to shorten the cleaning cycle of the inner wall of the tube body. At this time, the debris on the inner wall of the tube body is not firmly adhered to the inner wall of the tube body, so that the scraper ring can move smoothly.

[0009] Optionally, the sliding rod is made of non-ferromagnetic material, and a magnet corresponding to the tube body is fixedly connected to the end face of the tube sheet close to the cold flow outlet, and the end of the guide rail extends outside the tube body, and when the guide rail is energized, the direction of the magnetic flux lines within the range enclosed by the two guide rails and the sliding rod is the same as the direction of the magnetic flux lines of the magnet.

[0010] By adopting the above technical solution, when the shell is working, the slide bar is washed by the fluid to the end of the tube body near the cold flow outlet. When the work in the shell is completed and the inner wall of the tube body needs to be cleaned, it is only necessary to turn on the power supply near the end of the cold flow outlet. At this time, the slide bar is still affected by the magnetic field of the magnet. In the non-uniform magnetic field, the current is decomposed into many current elements I△L. According to △F=I△L·Bsin(I, B), (I, B) is the angle between the current direction and the magnetic field direction. Finally, multiple △Fs are added together to obtain the Ampere force of the slide bar. From the above formula, it can be seen that the Ampere force on the slide bar increases as the magnetic field intensity increases. That is, when there are too many debris on the inner wall of the tube body, the slide bar can also successfully break through the obstruction of the debris.

[0011] Optionally, the magnet is also fixedly connected to one end of the tube sheet away from the cold flow outlet, the scraper ring is fixedly connected to the slide rod, brushes are fixedly connected to both ends of the guide rail, two semicircular guide rings are rotatably provided at both ends of the tube body, the brushes are fitted with the guide rings, an armature facing the magnet is fixedly connected to the two guide rings, a plurality of scrapers with blades facing the side walls of the scraper ring are also fixedly connected to the guide ring, and when the scraper ring moves to the end of the tube body, the scraper and the scraper ring are abutted; the slide rod passes through the scraper ring, and the thickness of the slide rod along the length direction of the guide rail is less than the thickness of the scraper ring.

[0012] By adopting the above technical scheme, when the guide rail is energized, the current is transmitted to the guide ring through the brush, and then transmitted to the armature through the guide ring. At this time, the armature is electrically magnetized, and the direction of the magnetic flux lines of the armature can be obtained by Ampere's law. Since magnets of the same pole repel each other and opposite poles attract each other, the armature rotates. When the plane of the armature rotates to be parallel to the magnetic flux lines of the magnet, the two guide rings also exchange positions with each other and counteract the brushes, thereby changing the current of the armature, that is, changing the N and S poles of the armature, so that the polarity of the side of the armature close to the magnet always corresponds to the polarity of the side of the magnet close to the armature, so that the armature is always in a rotating state, and the guide ring also rotates due to the rotation of the armature, that is, the scraper is always in a rotating state; when the scraper ring moves to the end of the tube body, the scraper ring fits with the scraper moving in a circle, and the scraper scrapes off the debris attached to the scraper ring.

[0013] Optionally, the slide rod is a rectangular parallelepiped rod, and a slide groove adapted to slide with the slide rod is provided on one side of the tube body where the two guide rails are close to each other, and the end of the slide rod is inserted into the slide groove.

[0014] By adopting the above technical solution, the slide groove on the guide rail is adapted to the slide rod, so that the slide rod can only move along the length direction of the guide rail during movement and cannot rotate, thereby making the movement posture of the slide rod more stable, so that the scraper ring will not tilt during the scraping process, indirectly improving the scraping effect of the scraper ring.

[0015] Optionally, the limiting member is a limiting rod fixedly connected to the guide rail, and an energy absorbing layer is provided on a side of the limiting rod close to the sliding rod, and when the scraper abuts against the scraper ring, the energy absorbing layer is in a compressed state.

[0016] By adopting the above technical solution, when the sliding rod moves to the end of the tube body, the limit rod prevents the sliding rod from continuing to move, that is, the sliding rod is still subjected to the Ampere force and is close to the limit rod. During this process, when the sliding rod collides with the limit rod, the energy-absorbing layer effectively buffers the sliding rod, thereby reducing the damage suffered by the sliding rod during the collision. The buffering of the limit rod also effectively reduces the damage of the scraper to the scraper ring.

[0017] Optionally, a rotating shaft is fixedly connected to a side of the limiting rod away from the sliding rod, a supporting rod is rotatably connected to the rotating shaft, and two ends of the supporting rod are respectively fixedly connected to the inner walls of the two guide rings.

[0018] By adopting the above technical solution, the support rod stably supports the guide ring, so that the guide ring rotates more smoothly, and the support rod and the rotating shaft have a simple structure and high reliability. At the same time, the area of ​​the pipe opening of the pipe body blocked by the support rod and the rotating shaft is small, thereby having little impact on the flow rate of the fluid.

[0019] Optionally, a protective cover is provided on the end surface of the tube sheet close to the shell cover, the tube body passes through the protective cover, and a sealing layer is provided between the protective cover and the tube body and between the protective cover and the tube sheet.

[0020] By adopting the above technical solution, the circuits electrically connected between the guide rail and the external power supply are all received between the protective cover and the tube sheet, so that the circuits are isolated from the fluid, which can prevent the fluid from corroding the circuits and preventing the fluid from impacting and loosening the circuits. The double-layer isolation of the protective cover and the tube sheet effectively reduces the probability of fluid leakage from the gap between the tube body and the tube sheet.

[0021] Optionally, the tube body is made of high temperature resistant PEEK material.

[0022] By adopting the above technical solution, PEEK has good wear resistance, corrosion resistance and thermal conductivity, and PEEK also has strong mechanical strength. However, the steel pipe body is prone to rust after long-term use, especially when the fluid in contact with the pipe body wall is corrosive, the rust rate of the pipe body will be further accelerated, thereby aggravating the blockage of the pipe body.

[0023] In summary, the present application includes at least one of the following beneficial technical effects:

[0024] 1. When it is necessary to clean the inner wall of the tube body, the staff only needs to wait for the shell and tube heat exchanger to shut down, and then turn on the power supply near the cold flow outlet. At this time, the two guide rails, the slide rod and the external DC power supply in the tube body form a closed loop. The slide rod is acted on by the Ampere force and moves on the guide rail to the end near the cold flow inlet, thereby driving the scraper ring to move. The moving scraper ring can scrape off and push the debris on the inner wall of the tube body until the slide rod slides to the end of the guide rail, and the slide rod stops moving due to the action of the limiter. At this time, the scraper ring will also push the debris scraped off from the inner wall of the tube body out of the pipe mouth of the tube body, and then turn off the power supply at one end of the guide rail near the cold flow outlet and turn on the power supply at the other end. The slide rod moves to the side near the hot flow outlet again. Repeating the above process can make the scraper ring reciprocate in the tube body, effectively improving the cleaning effect of the scraper ring on the inner wall of the tube body;

[0025] 2. When the slide bar is located below the magnet, it is also affected by the magnetic field of the magnet, and the direction of the magnetic flux lines of the magnet is the same as that of the electromagnetism, that is, the magnetic field strength of the slide bar increases at this time, and the Ampere force on the slide bar also increases. That is, when there are too many debris on the inner wall of the pipe body, the slide bar can also successfully break through the obstruction of the debris, so that the scraper ring can smoothly perform the cleaning operation;

[0026] 3. When the guide rail is energized, the current is transmitted to the guide ring through the brush, and then to the armature through the guide ring. At this time, the armature is electrically magnetized, and because magnets of the same pole repel each other and opposite poles attract each other, the armature rotates. When the plane of the armature rotates to be parallel to the magnetic flux lines of the magnet, the two guide rings also exchange positions with each other and counteract the brushes, thereby changing the N and S poles of the armature, so that the polarity of the side of the armature close to the magnet always corresponds to the polarity of the side of the magnet close to the armature, so that the armature is always in a rotating state, and the guide ring also rotates due to the rotation of the armature, that is, the scraper is always in a rotating state; when the scraper ring moves to the end of the pipe body, the scraper ring fits with the scraper moving in a circle. At this time, the scraper scrapes off the debris attached to the scraper ring to prevent a large amount of debris from adhering to the scraper ring and affecting the removal efficiency of the scraper ring, and the entire mechanism occupies less space in the pipeline. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the present application;

[0028] Figure 2 is along Figure 1 Schematic diagram of the cross-sectional structure along the AA line;

[0029] Figure 3 yes Figure 2 Schematic diagram of the enlarged portion B.

[0030] Figure numerals: 11, shell; 111, hot flow inlet; 112, hot flow outlet; 12, shell cover; 121, cold flow inlet; 122, cold flow outlet; 13, tube body; 14, baffle; 15, tube sheet; 16, flange; 2, guide rail; 21, slide groove; 31, slide rod; 32, scraper ring; 4, magnet; 51, brush; 52, guide ring; 53, armature; 54, scraper; 6, limit rod; 61, energy absorption layer; 71, rotating shaft; 72, support rod; 8, protective cover. DETAILED DESCRIPTION

[0031] The following is combined with Figure 1-3 This application is described in further detail.

[0032] The present application discloses a gas-liquid two-phase flow shell and tube heat exchanger. Figure 1 , Figure 2 and Figure 3 The gas-liquid two-phase flow shell and tube heat exchanger comprises a shell 11, a shell cover 12 arranged at both ends of the shell 11, a plurality of high-temperature resistant PEEK tubes 13 arranged in the shell 11, a baffle 14 sleeved on the tube 13 and tube sheets 15 respectively fixed to both ends of the tube 13, the shell cover 12 is fixedly connected to a flange 16 at one end close to the shell 11, and both ends of the tube 13 are also fixedly connected to the flange 16, the shell cover 12 and the tube 13 are connected through the flange 16, the flange 16 is provided with a slot adapted to the tube sheet 15, and the tube sheet 15 is also fixed by two flanges 16, the shell 11 is respectively provided with a hot flow inlet 111 and a hot flow outlet 112 on two opposite sides between the two baffles, and a cold flow inlet 111 is provided on the shell cover 12 near the hot flow outlet 112. 21, a cold flow outlet 122 is provided on the shell cover 12 near one end of the hot flow inlet 111, two parallel guide rails 2 are arranged on two opposite sides of the inner wall of the tube body 13, a slide bar 31 is placed on the guide rail 2, both ends of the guide rail 2 are connected to an external DC power supply (because the power supply and the circuit connected thereto are prior art, and there are too many lines due to too many guide rails 2 in this application, in order to make it easier to see and understand the accompanying drawings, the power supply and the lines connected thereto are not drawn in the drawings), and the electrodes externally connected to the same end of the two guide rails 2 in the same tube body 13 are opposite, a scraper ring 32 is arranged on the slide bar 31, which is in contact with the inner wall of the tube body 13, the inner wall of the tube body 13 is insulated, and a limiter is also arranged on the guide rail 2 for limiting the slide bar 31 to move only along the length of the guide rail 2.

[0033] When it is necessary to clean the inner wall of the tube body 13, the staff only needs to wait until the shell and tube heat exchanger is shut down, and then turn on the power supply near the end of the cold flow outlet 122. At this time, the two guide rails 2, the slide bar 31 and the external DC power supply in the tube body 13 form a closed loop. According to the direction of current flow and Ampere's law, the direction of the magnetic flux lines within the range of the two guide rails 2 and the slide bar 31 close to the energized power supply side can be obtained. Then, by the left-hand rule, it can be obtained that the direction of the Ampere force exerted on the slide bar 31 is parallel to the guide rail 2 and points to the side of the cold flow inlet, that is, when the guide rail 2 is energized, the slide bar 31 is acted upon by the Ampere force and moves on the guide rail 2 toward the end close to the cold flow inlet, thereby driving the scraper ring 32 to move. The moving scraper ring 32 can scrape off the debris on the inner wall of the tube body 13 and push it until the slide bar 31 slides to the end of the guide rail 2 due to the action of the limiter The sliding rod 31 stops moving, and the scraper ring 32 also pushes out the debris scraped off the inner wall of the tube body 13 from the tube mouth of the tube body 13 at this time; after a period of time, that is, when the scraper rings 32 in all the tube bodies 13 move to the end of the guide rail 2 close to the cold flow inlet, the power supply at one end of the guide rail 2 close to the cold flow outlet 122 is turned off and the power supply at the other end is turned on, and the sliding rod 31 moves to the side close to the hot flow outlet 112 again, and the above process is repeated to make the scraper ring 32 reciprocate in the tube body 13, effectively improving the cleaning effect of the scraper ring 32 on the inner wall of the tube body 13. Compared with the method of driving the sliding rod 31 by adding a screw rod or other mechanism in the tube body 13, the screw rod occupies more space, and because the diameter of the tube body 13 is small and the tube body is generally long, the screw rod is also more likely to bend due to material limitations.

[0034] Reference Figure 3 The slide rod 31 is made of a non-ferromagnetic conductor material. The slide rod 31 can be made of copper, silver or the like. In the embodiment of the present application, the slide rod 31 is a copper rod. A magnet 4 corresponding to the tube body 13 is fixedly connected to the end surface of the tube sheet 15 close to the cold flow outlet 122. The end of the guide rail 2 extends outside the tube body 13. When the guide rail 2 is energized, the direction of the magnetic flux lines within the range enclosed by the two guide rails 2 and the slide rod 31 is the same as the direction of the magnetic flux lines of the magnet 4.

[0035] When fluid flows in the tube body 13, the slide bar 31 is washed by the fluid to one end of the tube body 13 near the cold flow outlet 122. When the work in the shell 11 and the tube body 13 is completed and the inner wall of the tube body 13 needs to be cleaned, it is only necessary to turn on the power supply near the end of the cold flow outlet 122. At this time, the slide bar 31 is still affected by the magnetic field of the magnet 4. Since the direction of the magnetic flux lines in the range enclosed by the two guide rails 2 and the slide bar 31 is the same as the direction of the magnetic flux lines of the magnet 4, that is, the magnetic field strength at the slide bar 31 is the magnetic field strength of the electromagnetic plus the magnetic field strength of the magnet 4. As the magnetic field strength of the slide bar 31 increases, the Ampere force on the slide bar 31 also increases. That is, when there are too many debris on the inner wall of the tube body 13, the slide bar 31 can also successfully break through the obstruction of the debris.

[0036] Reference Figure 2and Figure 3 A magnet 4 is also fixedly connected to one end of the tube sheet 15 away from the cold flow outlet 122, and in the embodiment of the present application, there are magnets 4 on the upper and lower sides of each tube body 13, and the facing surfaces of the two magnets 4 on the upper and lower sides are of opposite polarity, that is, one tube body 13 corresponds to four magnets 4. The scraper ring 32 is fixed to the slide bar 31, and brushes 51 are fixed to both ends of the guide rail 2. A rotating shaft 71 is fixed to the side of the limit rod 6 away from the slide bar 31, and a support rod 72 is rotatably connected to the end of the rotating shaft 71 away from the slide bar 31. Both ends of the support rod 72 are fixed to guide rings 52 with arcs facing each other on the inner sides. An armature 53 facing the magnet 4 is commonly fixed to the two guide rings 52. Several scrapers 54 with blades facing the side walls of the scraper ring 32 are also fixed to the guide ring 52, and when the scraper ring 32 moves to the end of the tube body 13, the scraper 54 abuts against the scraper ring 32; the slide bar 31 passes through the scraper ring 32, and the thickness of the slide bar 31 along the length direction of the guide rail 2 is less than the thickness of the scraper ring 32. In other feasible embodiments, the number of the guide rings 52 can be four, six, etc., that is, the corresponding number of the armatures 53 is two or three. The more armatures 53 there are, the faster and more stable the guide rings 52 rotate, but the corresponding space occupied is more. The specific number and size are set according to actual working conditions.

[0037] When the guide rail 2 is energized, the current is transmitted to the guide ring 52 through the brush 51, and then transmitted to the armature 53 through the guide ring 52. At this time, the armature 53 is electrically magnetized, and the direction of the magnetic flux lines of the armature 53 can be obtained by Ampere's law. Since the magnets 4 repel each other with like poles and attract each other with opposite poles, the armature 53 is rotated. When the plane of the armature 53 rotates to be parallel to the magnetic flux lines of the magnet 4, the two guide rings 52 also exchange positions with each other and counteract the brushes 51, thereby changing the current of the armature 53, that is, changing the N and S poles of the armature 53, so that the armature 53 is close to the side of the magnet 4. The polarity always corresponds to the polarity of the side of the magnet 4 close to the armature 53, so that the armature 53 is always in a rotating state, and the guide ring 52 also rotates due to the rotation of the armature 53, that is, the scraper 54 is always in a rotating state; when the scraper ring 32 moves to the end of the tube body 13, the scraper ring 32 fits with the scraper 54 moving in a circle. At this time, the scraper 54 scrapes off the debris attached to the scraper ring 32, avoiding the accumulation of debris on the end face of the scraper ring 32 due to lack of cleaning due to scraping off the debris, thereby reducing the accumulation of impurities and affecting the moving speed of the scraper ring 32.

[0038] Reference Figure 3The slide rod 31 is a rectangular rod. A slide groove 21 that is slidably matched with the slide rod 31 is opened on the side where the two guide rails 2 in the tube body 13 are close to each other. The end of the slide rod 31 is inserted into the slide groove 21. The limiting member is a limiting rod 6 fixed to the inner wall of the slide groove 21 of the guide rail 2. The limiting rod 6 is made of insulating PEEK material. An energy absorbing layer 61 is bonded to the side of the limiting rod 6 close to the slide rod 31. In the embodiment of the present application, the energy absorbing layer 61 is a high-temperature resistant rubber pad, and when the scraper 54 is against the scraper ring 32, the energy absorbing layer 61 is in a compressed state.

[0039] The limit rod 6 is also made of insulating material to prevent the limit rod 6 from interfering with the running state of the slide bar 31. The slide groove 21 adapted to the slide bar 31 is opened on the guide rail 2, so that the slide bar 31 can only move along the length direction of the guide rail 2 during movement and cannot rotate, thereby making the moving posture of the slide bar 31 more stable, so that the scraper ring 32 will not tilt during the scraping process, indirectly improving the scraping effect of the scraper ring 32, and when the scraper ring 32 hits the limit rod 6, the energy absorption layer 61 on the limit rod 6 effectively reduces the damage of the limit rod 6 to the scraper ring 32.

[0040] Reference Figure 2 and Figure 3 , a protective cover 8 is provided on the end surface of the tube sheet 15 close to the shell cover 12, the tube body 13 penetrates the protective cover 8, and a sealing layer is provided between the protective cover 8 and the tube body 13, and between the protective cover 8 and the tube sheet 15, the sealing layer is a glue sealing layer, and the protective cover 8 is also clamped in the clamping groove of the flange 16, that is, the protective cover 8 and the tube sheet 15 are fixed by the flange 16. The circuits electrically connected between the guide rail 2 and the external power supply are all received between the protective cover 8 and the tube sheet 15, so that the circuits are isolated from the fluid, which not only prevents the fluid from corroding the circuits but also prevents the fluid from impacting and loosening the circuits, and the double-layer isolation of the protective cover 8 and the tube sheet 15 effectively reduces the probability of fluid leakage from the gap between the tube body 13 and the tube sheet 15.

[0041] The implementation principle of a gas-liquid two-phase shell and tube heat exchanger in the embodiment of the present application is as follows: after the shell and tube heat exchanger is shut down, the staff turns on the power supply near the cold flow outlet 122. At this time, the two guide rails 2 in the tube body 13, the slide rod 31 and the external DC power supply form a closed loop. The slide rod 31 is acted upon by the Ampere force and moves on the guide rail 2 toward the end near the cold flow inlet, thereby driving the scraper ring 32 to move. The moving scraper ring 32 can scrape and push the debris on the inner wall of the tube body 13 until the slide rod 31 slides to the end of the guide rail 2, whereupon the slide rod 31 stops moving due to the action of the limiter. At this time, the scraper ring 32 also pushes the debris scraped off the inner wall of the tube body 13 out of the tube mouth of the tube body 13. At the same time, the current is transmitted to the guide ring 52 through the brush 51, and then transmitted to the armature 53 through the guide ring 52. At this time, the armature 53 generates magnetism, and because the magnets 4 repel each other with like charges and attract each other with opposite charges, the armature 5 3 rotates, and when the plane of the armature 53 rotates to be parallel to the magnetic flux lines of the magnet 4, the two guide rings 52 also exchange positions with each other and counteract the brush 51, thereby changing the polarity of the armature 53, so that the polarity of the side of the armature 53 close to the magnet 4 always corresponds to the polarity of the side of the magnet 4 close to the armature 53, thereby making the armature 53 always in a rotating state, and the guide ring 52 also rotates due to the rotation of the armature 53, that is, the scraper 54 is always in a rotating state; during the whole process, the scraper ring 32 reciprocates along the guide rail 2, and the scraper 54 performs a circular motion with the rotating shaft 71 as the axis. The reciprocating motion of the scraper ring 32 effectively cleans the debris on the inner wall of the tube body 13, and when the scraper ring 32 moves to the end of the tube body 13, the scraper ring 32 fits with the scraper 54 moving in a circular motion. At this time, the scraper 54 scrapes off the debris attached to the scraper ring 32 to prevent a large amount of debris from adhering to the scraper ring 32 and affecting the cleaning efficiency of the scraper ring 32.

[0042] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A gas-liquid two-phase flow shell and tube heat exchanger, comprising a shell (11), a shell cover (12) arranged at both ends of the shell (11), a plurality of tubes (13) arranged in the shell (11), a baffle (14) sleeved on the tubes (13), and tube sheets (15) respectively fixed to both ends of the tubes (13), wherein one end of the shell cover (12) close to the shell (11) is fixedly connected to a flange (16), and both ends of the tubes (13) are also fixedly connected to flanges (16). The shell cover (12) and the tube body (13) are connected via the flange (16); the shell (11) is provided with a hot flow inlet (111) and a hot flow outlet (112) at two opposite sides between the two tube sheets (15); a cold flow inlet (121) is provided on the shell cover (12) near one end of the hot flow outlet (112); and a cold flow outlet (122) is provided on the shell cover (12) near one end of the hot flow inlet (111); the characteristics are: Two mutually parallel guide rails (2) are arranged on two opposite sides of the inner wall of the tube body (13), a slide bar (31) is placed on the guide rail (2), both ends of the guide rail (2) are connected to an external DC power supply, and the electrodes externally connected to the same end of the two guide rails (2) in the same tube body (13) are opposite, a scraper ring (32) is arranged on the slide bar (31) and is in contact with the inner wall of the tube body (13), the inner wall of the tube body (13) is insulated, and a limiter is also arranged on the guide rail (2) for limiting the slide bar (31) to move only within the length range of the guide rail (2).

2. The gas-liquid two-phase flow shell and tube heat exchanger according to claim 1, characterized in that: The slide bar (31) is made of non-ferromagnetic material, and a magnet (4) corresponding to the tube body (13) is fixedly connected to the end surface of the tube plate (15) close to the cold flow outlet (122). The end of the guide rail (2) extends outside the tube body (13), and when the guide rail (2) is energized, the direction of the magnetic flux lines within the range enclosed by the two guide rails (2) and the slide bar (31) is the same as the direction of the magnetic flux lines of the magnet (4).

3. The gas-liquid two-phase flow shell and tube heat exchanger according to claim 2, characterized in that: The magnet (4) is also fixedly connected to one end of the tube plate (15) away from the cold flow outlet (122), the scraper ring (32) is fixedly connected to the slide bar (31), brushes (51) are fixedly connected to both ends of the guide rail (2), two semicircular guide rings (52) are rotatably provided at both ends of the tube body (13), the brushes (51) are fitted with the guide rings (52), and the two guide rings (52) are fixedly connected to the magnet. (4) facing the armature (53), the guide ring (52) is also fixed with a plurality of scrapers (54) whose blades face the side walls of the scraper ring (32), and when the scraper ring (32) moves to the end of the tube body (13), the scrapers (54) abut against the scraper ring (32); the slide bar (31) passes through the scraper ring (32), and the thickness of the slide bar (31) along the length direction of the guide rail (2) is less than the thickness of the scraper ring (32).

4. The gas-liquid two-phase flow shell and tube heat exchanger according to claim 1, characterized in that: The slide bar (31) is a rectangular parallelepiped rod, and a slide groove (21) adapted to slide with the slide bar (31) is provided on one side of the two guide rails (2) in the tube body (13) where the two guide rails (2) are close to each other, and the end of the slide bar (31) is inserted into the slide groove (21).

5. The gas-liquid two-phase flow shell and tube heat exchanger according to claim 3, characterized in that: The limiting member is a limiting rod (6) fixedly connected to the guide rail (2), and an energy absorbing layer (61) is provided on a side of the limiting rod (6) close to the sliding rod (31), and when the scraper (54) abuts against the scraper ring (32), the energy absorbing layer (61) is in a compressed state.

6. The gas-liquid two-phase flow shell and tube heat exchanger according to claim 5, characterized in that: A rotating shaft (71) is fixedly connected to the side of the limiting rod (6) away from the sliding rod (31), and a supporting rod (72) is rotatably connected to the rotating shaft (71). The two ends of the supporting rod (72) are respectively fixedly connected to the inner walls of the two guide rings (52).

7. The gas-liquid two-phase flow shell and tube heat exchanger according to claim 1, characterized in that: A protective cover (8) is provided on the end surface of the tube sheet (15) close to the shell cover (12); the tube body (13) passes through the protective cover (8); and sealing layers are provided between the protective cover (8) and the tube body (13) and between the protective cover (8) and the tube sheet (15).

8. The gas-liquid two-phase flow shell and tube heat exchanger according to claim 1, characterized in that: The tube body (13) is made of high temperature resistant PEEK material.

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