JPS6080094A - Cross-flow heat exchanger - Google Patents

Abstract

PURPOSE:To minimize the valiability in the pitches of respective fluid paths and increase the dimensional accuracy of the device by a method wherein partitioning plates, used both for positioning jigs which are provided with recesses for positioning the pitches equal to the pitches of a plurality of fluid paths, are inserted into corners of respective welding parts to determine said pitches correctly and weld the partitioning plates to respective heat exchanging elements. CONSTITUTION:The partitioning plate 26, provided with a plurality of positioning recesses 26a arranged with a pitch equal to the pitches of a plurality of fluid paths 23 formed so as to have the same shape as the shape in which the first welding part 19 is assembled, is inserted into the corner 15b between the first welding part 19 and the second welding part 20 and the end faces of respective welding parts 19, 20 are welded to aid partitioning plate respectively to seal the corner 15b and effect the positioning between mutual heat exchanging elements 22. According to this method, the pitches between a plurality of fluid paths 23 may be determind correctly and the variability in the pitches of the fluid paths 23, 24 may be eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flat plate type cross-flow heat exchanger suitable for one thick plate!
Particularly, the present invention relates to a cross-flow heat exchanger that requires a small amount of welding work, has a small amount of pitch deformation due to welding, has low residual stress, and has high airtightness.

Conventionally, a heat exchanger generally has a heat exchange surface between a high-temperature fluid and a low-temperature fluid, but in order to prevent fluid movement between the two fluids, it is necessary to weld the joints of the materials. be. In addition, in conventional large-capacity heat exchangers, single-tube type heat exchangers are often used, and there are almost no examples of single-plate type heat exchangers being put into practical use. However, the multi-tube heat exchanger has disadvantages in that it requires many man-hours to manufacture, assemble and weld each tube, resulting in high costs and a complicated structure.

The inventor of this application is 1 Japanese Patent Application No. 49-20964.
-310771 Patent No. 1144199), we proposed a flat plate type cross-flow heat exchanger suitable for thin plates.1 This is lightweight and compact, and has high airtightness.1 The heat load is small and S -1 It has gained popularity as an excellent flat plate type cross-flow heat exchanger that does not cause stress corrosion cracking even in a considerable stress corrosion environment, and has been put into practical use in large numbers to date.

However, the structure and welding method of the cross-flow heat exchanger according to the present invention are suitable for thin plates with a minimum thickness of about 0.3 mm, and are not suitable for large cross-flow heat exchangers using thick plates with a thickness of 3 mm or more. The problem was that it was not suitable.

Therefore, in order to obtain a flat plate type cross-flow heat exchanger that uses a flat plate material with a thickness of about 3 mm or more and has high strength and airtightness, the inventors of the present invention have developed a cross-flow heat exchanger as shown in Figs. A cross-flow heat exchanger 1 with such a structure and welding method was attempted. That is, 1. First, as shown in FIG. 1, the ends 2b of the heat exchange surface 3 made of a rectangular flat plate 2, which are parallel to two opposing sides, are bent to form an obtuse angle with one surface 3a of the heat exchange surface 3. A heat exchange element 6 having welded portions 4 is constructed by placing one element 6 upside down and facing the other element 6 as shown in FIG. A plurality of units 9 constituting the fluid passage 8 are prepared, and a plurality of units 9 are lined up, and a partition plate 1 is placed between them at a position slightly inside from the end surface 6a.
0)) Both corners 10a of the partition plate 10 are welded to the adjacent heat exchange element 6, and then the L-shaped seal plate 1 is welded.
1 is brought into contact with a part of the end surface 6a of the heat exchange element 6 of each unit 9, and the end surface 6a is welded to the sealing plate 11 as shown in FIG. The gap 12 between the two is also filled with beads B as shown in FIG. As a result, a cross-flow heat exchanger 1 having one fluid passage 8 and one fluid passage 13 orthogonal thereto is obtained.

However, with such a structure and welding method, the tortoise partition plates 10 are only placed between each unit 9 and are in a separate state, so it is difficult to determine the pitch between each unit 9, so it is difficult to determine the finished dimensions. The disadvantage was that the accuracy was not good. In addition, since both sides of the partition plate 10 are welded, the welding points are close to each other, and the heat load on the partition plate is large. As shown in FIG. As shown in , it had the disadvantage of being easily deformed. In addition, since the heat load on each partition plate 10 is large as described above, cracks at one welding point and cracks in the partition plate 10 are likely to occur, resulting in poor durability. Furthermore, since there are many welding points and gaps between the welding points, a large amount of welding material is consumed, and each welding process requires a large number of man-hours, making each work difficult and requiring a high level of skill. Moreover, due to the above, there is a drawback that the cost is high.

The present invention has been made to eliminate the above-mentioned drawbacks of the prior art, and has the following objects: 1. A rectangular recessed surface obtained by cutting the corners of a rectangular flat plate member with a large thickness. Heat exchange elements having corners and parallel ends curved in appropriate directions to form welds are combined and temporarily welded to form perpendicular fluid passages, one equal to the pitch of the plurality of fluid passages. A partition plate that also serves as a positioning jig and is provided with a recess for positioning the pitch is inserted into the corner of each welding part to accurately measure the pitch.1 By welding the partition plate and each heat exchange element, each To obtain a flat plate type cross-flow heat exchanger using a thick plate with high dimensional accuracy by reducing variation in the pitch of fluid passages. Another purpose is to slightly reduce the amount of tortoise welding and the amount of deformation during welding, thereby reducing the thermal load and residual stress. is to get an exchanger. Still another objective is to obtain a product with high airtightness without cracking of the welded part or cracking of the plate. Another purpose is to speed up the work and reduce costs by facilitating assembly and welding work.

In short, the present invention cuts four corners of a Sa-shaped flat plate to form four concave corners at right angles, and 1. A first welded portion is formed by curving in one direction from one side of the heat exchange surface, and an end parallel to the other two opposing sides is bent in a direction opposite to the one direction from the other side of the heat exchange surface. curved to form a second weld to form a heat exchange element; 1) the elements are assembled to form orthogonal fluid passages and the welds are welded to secure the elements together; 1) the elements are assembled to form orthogonal fluid passages; A partition plate provided with a plurality of positioning recesses formed in the same shape as the combined shape of the first welding part and arranged at a pitch equal to the pitch of the plurality of fluid passages is connected to the first welding part and the second welding part. The end faces of the first welding part and the second welding part are each welded to the partition plate to seal the corner and position the elements to each other. 1. The first welded portion and the second welded portion are finish welded in the longitudinal direction.

The present invention will be explained below based on embodiments shown in the drawings. 7th
As shown in the figure, 1. First, the four corners of the rectangular flat plate 15 (
The heat exchange surface 16 is cut out by cutting out the four corners 15b (shown by imaginary lines) and forming four corners 15b recessed at right angles. Next, referring also to FIG. 150 degrees)
The first welded portion 19 is formed by curving the shoulder toward the front side of the paper (to the right in FIG. 8) in FIG. 9, the ends 15a parallel to the other two opposing sides of the heat exchange surface 16 are arranged at right angles to the other surface 16b of the heat exchange surface 16. The other side (
The second welded portion 20 is formed by curving the welded portion 20 (lower side in FIG. 9). In this way, one heat exchange element 22 is constructed as shown in FIG. 10.

Next, as shown in FIG. 12, one heat exchange element 22 is combined to form perpendicular fluid passages 23 and 24, and the first welded part 19 and the second welded part 20 are temporarily welded or finish welded. to secure the elements together.

As shown in FIG. 11, a partition is provided with a plurality of positioning recesses 26a formed in the same shape as the combined shape of the first welded portion 19 and arranged at a pitch equal to the pitch of the plurality of fluid passages 23. Insert the plate 26 into the corner 15b between the first welding part 19 and the second welding part 20.
The end faces of the welded portion 19 and the second welded portion 2o are welded to the partition plate, respectively, to seal the corner portion 15b and position the heat exchange elements 22 with each other. Here, the first and second welding parts 1
9. If 20 and 20 are finish welded, they will come off and the welding will be completed.1 If these are temporarily welded, 1. Finish weld the first welded part and the second welded part in the longitudinal direction.1 For example, the high temperature fluid passage 23 and the low temperature fluid passage 24 are completely separated to prevent water leakage between the two fluids. Then, a side plate 28 is attached to this 1. A cross-flow heat exchanger 3 as shown in FIG.
0 is completed.

The present invention is constructed as described above, and its operation will be explained below. The heat exchange element 22 is manufactured from the rectangular flat plate 15 by cutting one corner 15a and one end 1.
5c and 15d, it is easy, and the first welded part 19 and the second welded part 20 of each element 22 are
The welding work is easy because each weld part is parallel and all aligned outward.

The partition plate 26 is provided with positioning recesses 26a having a pitch equal to the pitch of the plurality of fluid passages 23.
9 and the corner 15b of the second welding part 20, the pitch of the plurality of fluid passages 23 can be set accurately, and the variation in the pitch of the fluid passages 23 and 24 is 1, for example, 173 of the above-mentioned conventional example. .about.115, and a flat plate type cross-flow heat exchanger 30 made of a thick plate material with high dimensional accuracy, for example, a plate thickness of 3 mm or more, can be obtained.

The thermal load on the partition plate 26 during welding is reduced, and no welding strain that would close the first fluid passages 23 and 24 occurs. Also like this, partition plate 2
Since the heat load on 6 is small, the durability of 1 is improved without cracking of the welded portion or cracking of the partition plate 26.

In addition, since the partition plate 26 is welded to the end faces of the first welding part 19 and the second welding part 20, the welding part itself and the gap between the welding parts are small. The number of man-hours is also reduced by about 30% compared to the conventional example described above, making one welding operation easier.

Note that the angle of the inlet end 15c of the fluid passage 23 is about 60 degrees, and the angle of the inlet end 15d of the fluid passage 24 is about 180 degrees, and the angle of the inlet end 15d is about 180 degrees. There is no practical problem if a highly viscous fluid such as water is allowed to flow into the passage 23 and a less viscous fluid such as exhaust gas is allowed to flow into the single fluid passage 24.

The present invention is configured and operates as described above.\The corner portion of a rectangular flat plate member having a large thickness is cut to form a concave corner portion at a right angle, and the parallel end portion is A positioning jig is provided with four positioning parts with a pitch equal to the pitch of a plurality of fluid passages (by combining heat exchange elements curved in appropriate directions to form welded parts and welded to form orthogonal fluid passages). A partition plate that also serves as a tool is inserted into the corner of each welding part to accurately obtain the above pitch, and since the partition plate and each heat exchange element are welded, 1 variations in the pitch of each fluid passage are reduced 1 This has the effect of providing a flat plate type cross-flow heat exchanger using thick plates with high dimensional accuracy. The amount of groove welding and the amount of deformation during welding are reduced.1 As a result, thermal load and residual stress are reduced.1 A large-capacity cross-flow heat exchanger with high strength and ability to withstand stress corrosive environments can be obtained. There is. Furthermore, there is an effect that a product with high airtightness can be obtained without cracking of the welded part or cracking of the plate. Furthermore, it is an invention of extremely high industrial value, as it has many excellent effects such as easy assembly and welding work, speeding up one work, and reducing the cost of welding.

[Brief explanation of the drawing]

Figures 1 to 5 relate to the conventional example) Figure 1 is a perspective view showing a state where one heat exchange element is turned upside down and opposed to the other heat exchange element. Figure 2 is a welded part. Fig. 3 is a front view of the structure shown in Fig. 2. Fig. 4 is a longitudinal section taken along the line IV-IV in Fig. 3. Fig. 1 Fig. 5 is a cross-sectional view taken along the v-■ arrow in Fig. 3, and Figs. 6 to 17 show examples of the present invention. Fig. 7 is a plan view showing the state in which a heat exchange element is formed from a gigantic flat plate. Fig. 8 is a vertical cross-sectional view taken along the arrows ■-■ in Fig. 7. IK arrow cross-sectional view 1 No. 10
Figure 1 is a perspective view of the heat exchange element. Figure 11 is a perspective view of the heat exchange element and partition plate. Figure 12 is a perspective view showing the state in which the heat exchange elements are combined and temporarily welded. Figure 13 is a perspective view of the heat exchange element and the partition plate. Fig. 12 is a perspective view showing the state in which the partition plate is inserted into the heat exchange element and welding is completed. Fig. 14 is a partial front view of the one shown in Fig. 13. Fig. 15 is a diagonal plane of the X■ arrow in Fig. 14. Figure 1 1st
6 is a longitudinal cross-sectional view taken along the line XM-XVI in FIG. 14. FIG. 17 is a cross-sectional view taken along the line X--X■ in FIG. 15 is a flat plate % 15a is a corner s 15b is a corner s 15c
, 1.5d is the end portion 116, the heat exchange surface 116a is the heat exchange surface, one surface 116b is the heat exchange surface, the other surface 119 is the first welding portion 120, the second welding portion 122 is the heat exchange element 123
．． 24 is a fluid passage 126 and a partition plate 26a is a positioning recess. Patent applicant Kazuo Uchida, CEA Co., Ltd. agent and patent attorney

Claims (1)

[Claims] Four corners of a rectangular flat plate were cut out to form a recess at right angles.
forming two corners, and curving ends parallel to two opposing sides of the heat exchange surface made of the rectangular flat plate in one direction from one surface of the heat exchange surface to form a first welded portion. A second welded portion is formed by curving a thick end parallel to the other two opposing sides in a direction opposite to the one direction from the other side of the heat exchange surface to form a heat exchange element; are combined to form orthogonal fluid passages, and the welded parts are melted and brought into contact to fix the elements to each other, and 1) the first welded parts are formed in the same shape as the combined shape of the plurality of fluid passages; A partition plate provided with a plurality of positioning recesses arranged at pitches is inserted into the corner between the first welding part and the second welding part. The end faces of the parts are welded to the partition plate respectively to seal the corners and position the elements, and the first weld part and the second weld part are finish welded in the longitudinal direction. A cross-flow heat exchanger featuring: