A compact fin-tube heat exchanger and a method for preparing the same

Abstract

The present invention discloses a compact fin-tube heat exchanger, characterized in that: the heat exchanger includes a frame, a plurality of fin plates parallel to each other and distributed at equal distances are arranged in the frame, and the heat exchanger also includes a main water inlet pipe and a main water outlet pipe, the main water inlet pipe and the main water inlet pipe are respectively connected to the two ends of a plurality of serpentine coils, the serpentine coils are divided into a first serpentine coil and a second serpentine coil, and the two serpentine coils are distributed at intervals, the first serpentine coil is composed of a plurality of first heat exchange tubes and elbows connected end to end, and the second serpentine coil is composed of a plurality of second heat exchange tubes and elbows connected end to end, the first heat exchange tube and the second heat exchange tube have the same diameter, but the first heat exchange tube is longer than the second heat exchange tube, and the length difference between the two is at least twice the outer diameter thereof. A preparation method of the heat exchanger is also disclosed.

Description

Technical Field

[0001] The invention relates to the field of heat exchange equipment, in particular to a compact fin-tube heat exchanger and a method for preparing the heat exchanger. Background Art

[0002] A heat exchanger is a device that transfers part of the heat of a hot fluid to a cold fluid, also known as a heat exchanger. Heat exchangers play an important role in chemical, petroleum, power, food and many other industrial production. The main components of a heat exchanger are fins and heat exchange tubes, which are used to increase the heat exchange area and improve the heat exchange efficiency. At present, the heat exchanger composed of fins and stainless steel round heat exchange tubes has a minimum outer diameter spacing of more than 26mm for heat exchange tubes with an outer diameter of 14mm-16mm. If the spacing of the heat exchange tubes can be reduced, the heat exchange efficiency of the heat exchanger can be significantly improved. It can be used in working conditions where frosting is not serious, and play a role in energy saving, emission reduction and improving work efficiency. However, the elbows need to be welded at both ends of the heat exchange tube to form a serpentine tube connected end to end. If the spacing between adjacent heat exchange tubes is reduced, there will be a problem of insufficient operating space and inability to perform welding operations when welding the elbows. Therefore, the traditional heat exchanger is still unable to reduce the spacing between adjacent heat exchange tubes. Summary of the invention

[0003] The present invention aims to solve the above-mentioned deficiencies in the prior art and proposes a compact fin-tube heat exchanger with a simple structure, ingenious design, and reasonable layout, which can shorten the distance between adjacent heat exchange tubes, thereby improving heat exchange efficiency, saving energy and reducing emissions, and improving efficacy. A preparation method of the heat exchanger is also disclosed.

[0004] The technical solution of the present invention is: a compact fin-tube heat exchanger, characterized in that: the heat exchanger comprises a frame 1, a plurality of fin plates 2 which are parallel to each other and are equidistantly distributed are arranged in the frame 1, and the heat exchanger also comprises a main water inlet pipe 3 and a main water outlet pipe 4, the main water inlet pipe 3 and the main water outlet pipe 4 are respectively connected to the two ends of a plurality of serpentine coils, the serpentine coils are divided into a first serpentine coil and a second serpentine coil, and the two serpentine coils are distributed at intervals,

[0005] The first serpentine coil is composed of a plurality of first heat exchange tubes 5 and elbows 6 connected end to end, and the second serpentine coil is composed of a plurality of second heat exchange tubes 7 and elbows 6 connected end to end. The first heat exchange tube 5 and the second heat exchange tube 7 have the same diameter, but the first heat exchange tube 5 is longer than the second heat exchange tube 7, and the length difference between the two is at least twice the outer diameter thereof.

[0006] The fin plate 2 is provided with a plurality of fin holes distributed in an array, and the spacing between adjacent fin holes is less than 26 mm. The first heat exchange tube 5 and the second heat exchange tube 7 are inserted into the fin holes. The heat exchange tube is a stainless steel round tube with an outer diameter of 14 mm-16 mm.

[0007] A method for preparing the compact fin-tube heat exchanger as described above is characterized in that the method is carried out according to the following steps:

[0008] Step A. Cut the first heat exchange tube 5 and the second heat exchange tube 7 of two different lengths to ensure that the length difference between the two is at least twice its outer diameter.

[0009] Step B. Install multiple fin plates 2 in the prefabricated frame 1, and insert the second heat exchange tube 7 into the fin hole, leaving one row or one column of empty fin holes between two adjacent rows or columns of the second heat exchange tube 7,

[0010] Step C. Adjust the position of the second heat exchange tube 7 to the designed position, use dry compressed air to blow out the solid impurities in the second heat exchange tube 7, expand and tighten the second heat exchange tube 7 and the fin plate 2, and use dry compressed air to blow out the water in the second heat exchange tube 7.

[0011] Step D. Weld elbows 6 at both ends of the second heat exchange tube 7 to form a plurality of second serpentine coils distributed at intervals.

[0012] Step E. Insert the first heat exchange tube 5 into the remaining fin holes, adjust the position between the first heat exchange tube 5 and the fin plate 2, so that one end close to the main water inlet pipe 3 and the main water outlet pipe 4 is flush with the end of the second heat exchange tube 7,

[0013] Step F. Use dry compressed air to blow away the solid impurities in the first heat exchange tube 5, and weld an elbow 6 at one end of the first heat exchange tube 5 away from the main water inlet pipe 3 and the main water outlet pipe 4.

[0014] Step G. Push the first heat exchange tube 5 connected by the elbow 6 toward the main water inlet pipe 3 and the main water outlet pipe 4 so that it is flush with the second heat exchange tube 7.

[0015] Step H. All the first heat exchange tubes 5 are expanded and fastened to the fin plates 2, and the water in the first heat exchange tubes 5 is blown out with dry compressed air. Then, an elbow 6 is welded to one end of the first heat exchange tube 5 close to the main water inlet pipe 3 and the main water outlet pipe 4.

[0016] In the steps C and H, the expansion process adopts a hydraulic tube expansion process, and the expansion medium used is tap water.

[0017] In the steps C and H, the interference expansion between the outer diameter of the heat exchange tube and the fin hole after the expansion treatment must reach 0.05-0.3 mm.

[0018] In the steps C, F and H, the compressed air used must first be dehumidified by a dryer, and its relative pressure must be no less than 4 bar, and the blowing time must be no less than 15 seconds.

[0019] Compared with the prior art, the present invention has the following advantages:

[0020] This compact finned tube heat exchanger has a simple structure, ingenious design and reasonable layout. It aims to solve the problems that the traditional finned heat exchanger cannot shorten the distance between adjacent heat exchange tubes due to structural limitations, resulting in large overall space occupation and low heat exchange efficiency. A special structure is designed. The serpentine coil inside it has two specifications of long and short. By using this structure and a unique preparation method, a finned heat exchanger with a smaller spacing can be smoothly obtained. Compared with traditional heat exchangers, this heat exchanger has a relatively high heat exchange efficiency and can be widely used in various heat exchange fields under low frosting conditions. Moreover, its manufacturing process is simple and the manufacturing cost is low. Therefore, it can be said that it has many advantages and is particularly suitable for promotion and application in this field. Its market prospects are very broad. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic structural diagram of an embodiment of the present invention (direction one).

[0022] Figure 2 It is a schematic structural diagram of an embodiment of the present invention (direction two). DETAILED DESCRIPTION

[0023] The specific implementation of the present invention will be described below with reference to the accompanying drawings. Figure 1 , Figure 2 As shown: A compact fin-tube heat exchanger includes a frame 1 as a basis, a plurality of fin plates 2 which are parallel to each other and are equally spaced are arranged in the frame 1, and the heat exchanger also includes a main water inlet pipe 3 and a main water outlet pipe 4, the main water inlet pipe 3 and the main water outlet pipe 4 are respectively connected to the two ends of a plurality of serpentine coils, the serpentine coils are divided into a first serpentine coil and a second serpentine coil, and the two serpentine coils are spaced and distributed.

[0024] The first serpentine coil is composed of a plurality of first heat exchange tubes 5 and elbows 6 connected end to end, and the second serpentine coil is composed of a plurality of second heat exchange tubes 7 and elbows 6 connected end to end. The first heat exchange tube 5 and the second heat exchange tube 7 have the same diameter, but the first heat exchange tube 5 is longer than the second heat exchange tube 7, and the length difference between the two is at least twice the outer diameter thereof.

[0025] The fin plate 2 is provided with a plurality of fin holes distributed in an array, and the spacing between adjacent fin holes is less than 26 mm. The first heat exchange tube 5 and the second heat exchange tube 7 are inserted into the fin holes. The heat exchange tube is a stainless steel round tube with an outer diameter of 14 mm-16 mm.

[0026] A method for preparing a compact fin-tube heat exchanger as described above is carried out according to the following steps: first, cut two first heat exchange tubes 5 and second heat exchange tubes 7 of different lengths to ensure that the length difference between the two is at least twice their outer diameters; then install a plurality of fin plates 2 in a prefabricated frame 1, and insert the second heat exchange tube 7 into the fin holes, leaving a row or a column of empty fin holes between two adjacent rows or columns of second heat exchange tubes 7; then adjust the position of the second heat exchange tube 7 to reach the designed position, use dry compressed air to blow out solid impurities in the second heat exchange tube 7, expand and tighten the second heat exchange tube 7 and use dry compressed air to blow out water in the second heat exchange tube 7; weld elbows 6 at both ends of the second heat exchange tube 7 to form a plurality of second serpentine holes distributed at intervals. Coil; insert the first heat exchange tube 5 into the remaining fin holes, adjust the position between the first heat exchange tube 5 and the fin plate 2, and make its end close to the main water inlet pipe 3 and the main water outlet pipe 4 flush with the end of the second heat exchange tube 7; use dry compressed air to blow out the solid impurities in the first heat exchange tube 5, and weld the elbow 6 at the end of the first heat exchange tube 5 away from the main water inlet pipe 3 and the main water outlet pipe 4; push the first heat exchange tube 5 connected by the elbow 6 toward the direction of the main water inlet pipe 3 and the main water outlet pipe 4 to make it flush with the second heat exchange tube 7; expand and tighten all the first heat exchange tubes 5 and the fin plate 2, blow out the water in the first heat exchange tube 5 with dry compressed air, and then weld the elbow 6, the main water inlet pipe 3 and the main water outlet pipe 4 at the end of the first heat exchange tube 5 close to the main water inlet pipe 3 and the main water outlet pipe 4.

[0027] In the above steps, the expansion process adopts hydraulic expansion process, and the expansion medium used is tap water; and the interference expansion between the outer diameter of the heat exchange tube and the fin hole after the expansion process must reach 0.05-0.3mm; at the same time, the compressed air used must first be dehumidified by a dryer, and its relative pressure must be not less than 4bar, and the blowing time must be not less than 15s.

[0028] Since the heat exchanger includes two kinds of serpentine coils, and the two kinds of serpentine coils are spaced apart, and the overall lengths of the two kinds of serpentine coils are not the same, during installation, the elbow 6 of the shorter serpentine coil can be welded at the left end of the heat exchanger first, and then the first heat exchange tube 5 can be inserted into the fin plate 2, so that the first heat exchange tube 5 protrudes from the second heat exchange tube 7 at the left end. Since the two kinds of serpentine coils are spaced apart, when the elbow 6 of the first heat exchange tube 5 is welded in this state, it will not be affected by the elbow 6 on the second heat exchange tube 7. After the welding work on the left end of the first heat exchange tube 5 is completed, the longer first serpentine coil is pushed out toward the right end as a whole, so that the first heat exchange tube 5 protrudes from the second heat exchange tube 7 at the right end. In this way, the ends of the first heat exchange tube 5 and the second heat exchange tube 7 at the right end are staggered with each other. At this time, the above-mentioned welding elbow 6, the main water inlet pipe 3 and the main water outlet pipe 4 are repeated at the right end, and finally the welding operation of the first heat exchange coil and the second heat exchange coil is completed.

Claims

1. A compact fin-tube heat exchanger, characterized in that: The heat exchanger comprises a frame (1), wherein a plurality of fin plates (2) are arranged in parallel with each other and are equidistantly distributed. The heat exchanger also comprises a main water inlet pipe (3) and a main water outlet pipe (4), wherein the main water inlet pipe (3) and the main water outlet pipe (4) are respectively connected to two ends of a plurality of serpentine coils, wherein the serpentine coils are divided into a first serpentine coil and a second serpentine coil, and the two serpentine coils are distributed at intervals. The first serpentine coil is composed of a plurality of first heat exchange tubes (5) and elbows (6) connected end to end, and the second serpentine coil is composed of a plurality of second heat exchange tubes (7) and elbows (6) connected end to end, the first heat exchange tube (5) and the second heat exchange tube (7) having the same diameter, but the first heat exchange tube (5) is longer than the second heat exchange tube (7), and the difference in length between the first heat exchange tube (5) and the second heat exchange tube (7) is at least twice their outer diameters. The fin plate (2) is provided with a plurality of fin holes distributed in an array, and the spacing between adjacent fin holes is less than 26 mm. The first heat exchange tube (5) and the second heat exchange tube (7) are inserted into the fin holes. The heat exchange tubes are stainless steel round tubes with an outer diameter of 14 mm to 16 mm.

2. A method for preparing a compact fin-tube heat exchanger according to claim 1, characterized in that: The method described is carried out according to the following steps: Step A. Cut the first heat exchange tube (5) and the second heat exchange tube (7) into two different lengths, ensuring that the difference in length between the two is at least twice their outer diameters. Step B. Install multiple fin plates (2) in a prefabricated frame (1), and insert the second heat exchange tubes (7) into the fin holes, leaving one row or one column of empty fin holes between two adjacent rows or columns of the second heat exchange tubes (7). Step C. Adjust the position of the second heat exchange tube (7) to reach the designed position, use dry compressed air to blow away the solid impurities in the second heat exchange tube (7), expand and tighten the second heat exchange tube (7) and the fin plate (2), and use dry compressed air to blow away the water in the second heat exchange tube (7). Step D. Weld elbows (6) at both ends of the second heat exchange tube (7) to form a plurality of second serpentine coils distributed at intervals. Step E. Insert the first heat exchange tube (5) into the remaining fin holes, adjust the position between the first heat exchange tube (5) and the fin plate (2) so that one end of the first heat exchange tube (5) close to the main water inlet pipe (3) and the main water outlet pipe (4) is flush with the end of the second heat exchange tube (7), Step F. Use dry compressed air to blow away solid impurities in the first heat exchange tube (5), and weld an elbow (6) at one end of the first heat exchange tube (5) away from the main water inlet pipe (3) and the main water outlet pipe (4). Step G. Push the first heat exchange tube (5) connected by the elbow (6) toward the main water inlet pipe (3) and the main water outlet pipe (4) so ​​that it is flush with the second heat exchange tube (7). Step H. All the first heat exchange tubes (5) are expanded and fastened to the fin plates (2), and the water in the first heat exchange tubes (5) is blown away with dry compressed air. Then, an elbow (6) is welded to one end of the first heat exchange tube (5) close to the main water inlet pipe (3) and the main water outlet pipe (4).

3. The method for preparing a compact fin-tube heat exchanger according to claim 2, characterized in that: In the steps C and H, the expansion process adopts a hydraulic tube expansion process, and the expansion medium used is tap water.

4. The method for preparing a compact fin-tube heat exchanger according to claim 2, characterized in that: In the steps C and H, the interference expansion between the outer diameter of the heat exchange tube and the fin hole after the expansion treatment must reach 0.05-0.3 mm.

5. The method for preparing a compact fin-tube heat exchanger according to claim 2, characterized in that: In the steps C, F and H, the compressed air used must first be dehumidified by a dryer, and its relative pressure must be no less than 4 bar, and the blowing time must be no less than 15 seconds.

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