Tubular heat exchanger and packaging method of tubular heat exchanger

A tubular heat exchanger includes an upper tube plate box, a lower tube plate box, a plurality of heat exchange tubes, and a pressure bolt. Each heat exchange tube includes an inlet end and an outlet end opposite to the inlet end, the inlet end passes through the upper tube plate box, the outlet end passes through the lower tube plate box, the first sealing rubber is filled in a gap between the plurality of heat exchange tubes and the upper tube plate box, and the second sealing rubber is filled in a gap between the plurality of the heat exchange tubes and lower tube plate box. The pressure bolt is located between the upper tube plate box and the lower tube plate box. The present application also relates to a packaging method of the tubular heat exchanger.

FIELD

The present application relates to a tubular heat exchanger and a packaging method of the tubular heat exchanger.

BACKGROUND

Tubular heat exchangers are widely used in the fields of coking industry, metallurgy, chemical industry, hazardous waste incineration system, boiler industry, waste heat recovery system, and urban sewage treatment, etc. Tubular heat exchangers are usually used in a harsh environment, the working temperature and pressure of the heat exchange medium are relatively high, and the use environment has certain corrosiveness, which requires the packaging process between the heat exchange tubes of the tubular heat exchanger and the tube plate to have high performance indicators.

The connection methods between heat exchange tube and tube plate mainly includes expansion joint, welding, explosion connection, and expansion welding connection, etc. Different connection methods will affect the connection quality of heat exchange tube and tube plate. On the one hand, with the equivalent diameter of heat exchange tube decreases (such as less than 1 mm) and tube wall becomes thinner (such as less than 0.1 mm), the above-mentioned connection method will cause the tube wall of the heat exchange tube to rupture, and some connection methods are easy to block the heat exchange tube, which is time-consuming and laborious to process. It is difficult to achieve large-scale processing, and the expansion method is not suitable for the connection of non-circular heat exchange tubes (such as elliptical tubes, drop-shaped tubes) and tube plates. On the other hand, for tubular heat exchangers used in special occasions (such as strong corrosiveness, etc.), when using non-metallic heat exchange tubes, the welding method or the expansion method is no longer applicable, and improper processes will affect the use and lifespan of the heat exchanger.

Therefore, there is room for improvement in the art.

DETAILED DESCRIPTION

The term “outside” refers to a region that is beyond the outermost confines of a physical object. The term “inside” indicates that at least a portion of a region is partially contained within a boundary formed by the object. The term “substantially” is defined to essentially conforming to the particular dimension, shape or other word that substantially modifies, such that the component need not be exact. For example, substantially cylindrical means that the object resembles a cylinder, but can have one or more deviations from a true cylinder. The term “comprising” means “including, but not necessarily limited to”; it specifically indicates open-ended inclusion or membership in a so-described combination, group, series and the like. It should be noted that references to “an” or “one” embodiment in this disclosure are not necessarily to the same embodiment, and such references mean at least one.

Referring toFIGS.1and2, a tubular heat exchanger10is provided. The tubular heat exchanger10includes an upper tube plate box1, a lower tube plate box11, and a plurality of heat exchange tubes3. Each of the plurality of heat exchange tubes3includes an inlet end and an outlet end. The inlet ends of the plurality of heat exchange tubes3pass through the upper tube plate box1, and the outlet ends of the plurality of heat exchange tubes3pass through the lower tube plate box11. The shape of each of the upper tube plate box1and the lower tube plate box11is not limited, and can be a rectangular parallelepiped, a cube, or a cylinder, etc. The upper tube plate box1and the lower tube plate box11play a fixed support and sealing role for the heat exchange tubes3. In one embodiment, the upper tube plate box1and the lower tube plate box11are rectangular parallelepipeds. The structures of the upper tube plate box1and the lower tube plate box11are the same, the connection manner of the upper tube plate box1and the plurality of heat exchange tubes3is the same as the connection manner of the lower tube plate box11and the plurality of heat exchange tubes3, the sealing manner of the upper tube plate box1and the plurality of heat exchange tubes3is the same as the sealing manner of the lower tube plate box11and the plurality of heat exchange tubes3. Therefore, in one embodiment, only the above upper tube plate box1is taken as an example for detailed description.

The material of the plurality of heat exchange tubes3is not limited, and can be various types of non-metal tubes such as glass tubes, metal tubes, and the like. The cross-sectional shape of the heat exchange tube3can be circular or non-circular, such as oval, drop shape, etc. The equivalent diameter of the heat exchange tube3is in a range from 0.2 mm to 200 mm. The arrangement of the heat exchange tubes3can be in-line or crossed, and the distance between two adjacent heat exchange tubes3is 0.8 to 3 times the equivalent diameter of the heat exchange tubes3, but it is not limited to this. In one embodiment, the heat exchange tube3is a metal tube, the cross-sectional shape of the heat exchange tube3is circular, the diameter of the heat exchange tube3is 0.5 mm, and the heat exchange tubes3are parallel to each other. The heat exchange tubes3are normal pressure, slightly positive pressure or negative pressure pipes, and a plurality of heat exchange tubes3are positioned and fixed by the tube plates of the upper tube plate box1and the lower tube plate box11.

The upper tube plate box1includes an upper tube plate4, a lower tube plate7and a side plate6. The upper tube plate4, the lower tube plate7, and the side plate6form a cavity. The upper tube plate4defines a plurality of opening, the lower tube plate7defines a plurality of opening, and the openings of the upper tube plate4and the openings of the lower tube plate7correspond one-to-one. There is a one-to-one relationship between the multiple heat exchange tubes3and the multiple openings. The upper tube plate4, the lower tube plate7, and the side plates6can be fixed by bolts, or the upper tube plate box1can be formed by 3D printing. The inlet end of the heat exchange tube3penetrates the corresponding openings of the upper tube plate4and the lower tube plate7. The cavity of the upper tube plate box1is filled with elastic sealing rubber, and the heat exchange tube3is fixed in the cavity of the upper tube plate box1by the sealing rubber. Moreover, the sealing rubber is filled into the gap between the heat exchange tube3at the opening of the upper tube plate4and the upper tube plate4, and the sealing rubber is also filled into the gap between the heat exchange tube3at the opening of the lower tube plate7and the lower tube plate7, so that the heat exchange tube3is fixed and sealed with the upper tube plate4and the lower tube plate7. In one embodiment, the fixing and sealing of the heat exchange tube3and the upper tube plate4are only realized by sealing rubber, the fixing and sealing of the heat exchange tube3and the lower tube plate7are only realized by sealing rubber, and other fixing and sealing methods are not included. The sealing rubber plays a role of sealing, flexible fixing, and restraint. The above-mentioned sealing rubber does not have a specific type, and can be selected and used according to the specific application environment of the tubular heat exchanger10. Specifically, the sealing rubber may be a silicone rubber series, a polysulfide rubber series, a urethane rubber series, a diene rubber series, and the like.

The structure of the lower tube plate box11is the same as the structure of the upper tube plate box1and will not be repeated here.

In one embodiment, a pressure bolt9is provided on the side plate6of the upper tube plate box1, and the pressure bolt9is perpendicular to the axial direction of the heat exchange tube3. The pressure bolt9is used to apply and adjust the sealing pressure, so that a flexible connection mode between the heat exchange tube3and the tube plate is realized. Of course, the position where the pressure bolt9is set is not limited, and the pressure bolt9can also be set on the top or bottom plate of the upper tube plate box1, as long as the sealing pressure can be applied and adjusted.

The tubular heat exchanger10further includes a connecting flange8, the connecting flange8is connected to the tube plate box along the axial direction of the heat exchange tube3, and is used to install the head box of the tubular heat exchanger10.

The working temperature of the tubular heat exchanger10is not higher than the normal use temperature of the sealing rubber. Generally, the working temperature of the hot and cold fluid inside and outside of the tubular heat exchanger10is in a range from −70 degrees Celsius to 250 degrees Celsius, and the working pressure can be normal pressure, slightly positive pressure, or negative pressure.

In one embodiment, the fixing and sealing method of the heat exchange tube3and the upper tube plate4is only realized by sealing rubber, the fixing and sealing method of the heat exchange tube3and the lower tube plate7is only realized by sealing rubber, and other fixing and sealing methods are not included. Therefore, this connection method greatly reduces the requirements on the shape of the heat exchange tube3. In addition, the diameter of the heat exchange tube3can be thinner, and the heat exchange tube3with an equivalent tube diameter of about 100 microns can be used, and the tube wall can be thinner, and a heat exchange tube3with a wall thickness of tens of microns can be used. The tubular heat exchanger10with thinner and thinner heat exchange tubes3has better heat dissipation effect.

When the areas of the upper tube plate4and the lower tube plate7are large, and the pressure in the cavity of the upper tube plate box1is high, the upper tube plate4and the lower tube plate7are likely to be deformed, thereby affecting the heat dissipation effect of the tubular heat exchanger10. Therefore, along the axial direction of the heat exchange tube3, a tie rod2is provided between the upper tube plate4and the lower tube plate7, so that the upper tube plate4and the lower tube plate7are rigidly fixed. The two ends of the tie rod2are respectively fixed on the upper tube plate4and the lower tube plate7, one end of the tie rod2is welded to the upper tube plate4or the lower tube plate7, and the other end of the tie rod2is fixed to the lower tube plate7or the upper tube plate4by welding, screw connection or bolt-nut connection, thereby preventing the deformation of the upper tube plate4and the lower tube plate7, maintaining the pressure in the cavity of the upper tube plate box1, and increasing the rigidity of the upper tube plate box1. The number of tie rods2and the distance between tie rods2can be calculated according to actual applications. Specifically, the tie rod2can be made of a metal material that is resistant to the corrosion of the sealing rubber. For example, the tie rod2can be made of iron, copper, aluminum, stainless steel, and so on. In one embodiment, the tie rod2can be an iron rod. It can be understood that the tube plate boxes1,11and the tie rods2can also be integrally formed by mechanical cutting and welding processing, or 3D printing.

The two opposite ends of the heat exchange tube3respectively pass through the tube plates of the upper tube plate box1and the lower tube plate box11, and are fixed and connected by sealing rubber and pressure bolts9. The sizes of the tube plate boxes1,11can be selected according to the number of the heat exchange tubes3, and the tube diameter of the heat exchange tubes3, and the distance between two adjacent heat exchange tubes3. The tube plates on both sides of the tube plate box are fixed by the tie rods2. Through the sealing rubber, pressure bolts9, and tie rods2filled in the tube plate boxes1,11, a rigid and flexible connection between the tubes and the tube plate is realized.

In addition, the embodiment of the present application provides a packaging method of the tubular heat exchanger10. Referring toFIG.3. The packaging method of the tubular heat exchanger10includes the following steps:

S1, provide an upper tube plate box1, a lower tube plate box11, and a plurality of heat exchange tubes3, wherein the upper tube plate box1defines multiple openings, the lower tube plate box11defines multiple openings, and the plurality of heat exchange tubes pass through the openings of the upper tube plate box1and the lower tube plate box11;

S2, filling the upper tube plate box1and the lower tube plate box11with liquid sealing rubber, wherein the liquid sealing rubber is filled in the gap between the heat exchange tube3and the upper tube plate box1, the liquid sealing rubber is also filled in the gap between the heat exchange tube3and the lower tube plate box11, and then the liquid sealing rubber is solidified, so that multiple heat exchange tubes3are sealed and fixed in the upper tube plate box1and the lower tube plate box11; and

S3, installing the pressure bolts9on the upper tube plate box1and the lower tube plate box11to apply and adjust the sealing pressure.

During step S1, the upper tube plate box1includes an upper tube plate4, a lower tube plate7and a side plate6. The upper tube plate4, the lower tube plate7, and the side plate6form a cavity. The upper tube plate4defines a plurality of opening, the lower tube plate7defines a plurality of opening, and the openings of the upper tube plate4and the openings of the lower tube plate7correspond one-to-one. The upper tube plate4, the lower tube plate7, and the side plates6can be fixed by bolts, or the upper tube plate box1can be formed by mechanical cutting and welding processing or 3D printing. The structure of the lower tube plate box11is the same as the structure of the upper tube plate box1and will not be repeated here.

The material of the plurality of heat exchange tubes3is not limited, and can be various types of non-metal tubes such as glass tubes, metal tubes, and the like. The cross-sectional shape of the heat exchange tube3can be circular or non-circular, such as oval, drop shape, etc. The equivalent diameter of the heat exchange tube3is in a range from 0.2 mm to 200 mm. The arrangement of the heat exchange tubes3can be in-line or crossed, and the distance between two adjacent heat exchange tubes3is 0.8 to 3 times the equivalent diameter of the heat exchange tubes3, but it is not limited to this. The heat exchange tubes3are normal pressure, slightly positive pressure or negative pressure pipes. The inlet ends of the plurality of heat exchange tubes3pass through the upper tube plate box1, and the outlet ends of the plurality of heat exchange tubes3pass through the lower tube plate box11. The heat exchange tubes3are positioned and fixed by the tube plates of the upper tube plate box1and the lower tube plate box11. In one embodiment, the heat exchange tube3is a metal tube, the cross-sectional shape of the heat exchange tube3is circular, the diameter of the heat exchange tube3is 0.5 mm, and the heat exchange tubes3are parallel to each other.

During step2, the upper tube plate box1and the lower tube plate box11are filled with the liquid sealing rubber. The liquid sealing rubber is filled in the gap formed between the heat exchange tube3and the upper tube plate box1, the liquid sealing rubber is also filled in the gap formed between the heat exchange tube3and the lower tube plate box11, and then the liquid sealing rubber is solidified, so that multiple heat exchange tubes3are sealed and fixed in the upper tube plate box1and the lower tube plate box11. Since the liquid sealing rubber has good fluidity, as long as the filling amount is sufficient, the liquid sealing rubber can flow into the gap formed between the heat exchange tube3and the upper tube plate box1, and the gap formed between the heat exchange tube3and the lower tube plate box11. When the liquid sealing rubber is cured, the liquid sealing rubber solidifies into a solid sealing rubber and becomes an elastic body. The sealing rubber is filled into the gap between the heat exchange tube3at the opening of the upper tube plate4and the upper tube plate4, and the sealing rubber is also filled into the gap between the heat exchange tube3at the opening of the lower tube plate7and the lower tube plate7. There is no specific type of liquid sealing rubber, and the liquid sealing rubber can be selected and used according to the specific application environment of the tubular heat exchanger10. The viscosity of the liquid sealing rubber ranges from 500 mpa·s to 100000 mpa·s. In one embodiment, the viscosity of the liquid sealing rubber ranges from 2000 mpa·s to 20000 mpa·s. Specifically, the liquid sealing rubber can be a silicone rubber series, a polysulfide rubber series, a urethane rubber series, a diene rubber series, and the like. In one embodiment, the liquid sealing rubber is a liquid silicone rubber series.

It is understandable that the sealing rubber can also be in granular or powder form before filling the upper tube plate box1and the lower tube plate box11. When the granular or powdered sealing rubber is filled into the upper tube plate box1and the lower tube plate box11, the granular or powdered sealing rubber must undergo high temperature to soften into fluid, and then the fluid is filled into the upper tube plate box1and the lower tube plate box11.

During step3, the pressure bolts9are installed on the upper tube plate box1and the lower tube plate box11, and the sealing pressure is applied and adjusted by the pressure bolts9to realize the flexible connection between the heat exchange tube3and the tube plate. In one embodiment, the pressure bolts9are installed on the side plates6of the upper tube plate box1and the lower tube plate box11, and the pressure bolts9are installed in a direction perpendicular to the heat exchange tube3.

The upper tube plate box1and the lower tube plate box11are filled with sealing rubber. The sealing rubber can withstand high and low temperatures, has good elasticity and incompressibility, and has a wide operating temperature range. The sealing rubber is filled into the gap between the heat exchange tube3and the tube plate, and the sealing rubber plays a role of sealing and flexible fixing. When the pressure bolts9are installed in the upper tube plate box1and the lower tube plate box11, due to the incompressibility of the sealing rubber, as soon as the sealing rubber is squeezed, the pressure rises, and the sealing rubber is squeezed into the gap between the heat exchange tube3and the openings of and the tube plate, so that the heat exchange tube3and the tube plate is sealed and fixed.

During step1, when the areas of the upper tube plate box1and the lower tube plate box11are large, and the pressure in the cavity of the upper tube plate box1and the lower tube plate box11are high, the upper tube plates4and the lower tube plates7of the upper tube plate box1and the lower tube plate box11are likely to be deformed, which will affect the heat dissipation effect of the tubular heat exchanger10. Therefore, along the axial direction of the heat exchange tube3, a tie rod2is located between the upper tube plate4and the lower tube plate7to rigidly fix the upper tube plate4and the lower tube plate7. The two opposite ends of the tie rod2are respectively fixed on the upper tube plate4and the lower tube plate7. One end of the tie rod2is welded to the upper tube plate4or the lower tube plate7, and the other end of the tie rod2is fixed to the lower tube plate7or the upper tube plate4by welding, screw connection or bolt-nut connection, thereby preventing the deformation of the upper tube plate4and the lower tube plate7, maintaining the pressure in the cavities of the upper tube plate box1and the lower tube plate box11, and increasing the rigidity of the upper tube plate box1and the lower tube plate box11. The number of tie rods2and the distance between two adjacent tie rods2can be calculated according to actual applications. Specifically, the tie rod2can be made of a metal material that is resistant to the corrosion of the sealing rubber. For example, the tie rod2can be made of iron, copper, aluminum, stainless steel, and so on. It can be understood that the tube plate box1,11and the tie rods2can also be integrally formed by mechanical cutting and welding processing, or 3D printing.

The packaging method of the tubular heat exchanger10in the embodiment of the present application changes the connection mode (welding, expansion joint, expansion welding combination, etc.) of the traditional tubular heat exchange and the tube plate. Through the elasticity, fluidity and incompressibility of the sealing rubber, the heat exchange tube3and the tube plates4,7are sealed and fixed, and the flexible connection of the heat exchange tube3and the tube plates4,7is realized. Therefore, the packaging method of the tubular heat exchanger10can quickly connect multiple heat exchange tubes3to the tube plates4,7. The packaging method is convenient to complete the connection and sealing of the heat exchange tube3and the tube plates4,7at the same time, and is suitable for the processing technology of metal or non-metallic tubular heat exchanger. Therefore, the packaging method of the tubular heat exchanger10can complete the packaging at one time, which saves time and effort, can realize large-scale processing, and does not affect the use and lifespan of the tubular heat exchanger10.

Moreover, since rubber is used to seal and fix the heat exchange tube3and the tube plates4,7, the requirements for the shape of the heat exchange tube3are greatly reduced, and the diameter and the tube wall of the heat exchange tube3can be thinner. The tubular heat exchanger10with thinner and thinner heat exchange tubes3has better heat dissipation effect.

When the areas of the upper tube plate box1and the lower tube plate box11are large, the tie rod2is set between the upper tube plates4and the lower tube plates7of the upper tube plate box1and the lower tube plate box11to rigidly fix the upper tube plate4and the lower tube plate7, which can prevent the deformation of the upper tube plate4and the lower tube plate7, maintain the pressure in the cavities of the upper tube plate box1and the lower tube plate box11, and increase the rigidity of the upper tube plate box1and the lower tube plate box11.

The packaging method of the tubular heat exchanger10of the present application is mainly aimed at the connection between the heat exchange tube3and the tube plates4,7, and is suitable for low-temperature flue gas waste heat recovery, sewage treatment and other fields. The material of the heat exchange tube3can be a metal tube or a non-metal tube. The pipe diameter has a wide variation range, and the heat exchange tube3can work under normal pressure, slightly positive pressure, or negative pressure.

It is to be understood that the above-described embodiments are intended to illustrate rather than limit the disclosure. Any elements described in accordance with any embodiments is understood that they can be used in addition or substituted in other embodiments. Embodiments can also be used together. Variations may be made to the embodiments without departing from the spirit of the disclosure. The above-described embodiments illustrate the scope of the disclosure but do not restrict the scope of the disclosure.