JP6153583B2 - Method for producing metal plate, and use of metal plate produced by the production method for plate heat exchanger - Google Patents

Description

  The present invention relates to a method for producing a metal plate, and use of the metal plate produced by the production method for a plate heat exchanger.

  There are various types of heat exchangers, but plate heat exchangers have extremely high heat exchange performance, and are therefore used in electric water heaters, industrial equipment, automobile air conditioners, and the like. In the plate heat exchanger, a heat exchange medium passage, that is, a hot medium passage and a cold medium passage are formed adjacent to each other by stacked plates, and a medium having a temperature difference flowing between the high temperature medium passage and the low temperature medium passage is provided. It is configured to exchange heat with each other by transferring heat.

For example, in Patent Document 1, a plurality of plates with wave shapes serving as flow paths are stacked, and the plates are joined by various joining methods (fastening with gaskets and screws, welding, brazing). Thus, a laminated structure in which high-temperature flow paths and low-temperature flow paths exist alternately is produced.
Moreover, the heat exchanger uses a stainless steel plate having excellent corrosion resistance as a metal plate of the material from the viewpoint of improving durability. The small and medium heat exchangers are often joined by brazing in consideration of pressure resistance.

JP 2010-85094 A

By the way, the performance of the plate heat exchanger becomes better as the area of the flow path formed by the mutual gap between the stacked metal plates is larger and the thickness of the metal plate is thinner. The larger the processing height h / W, which is the ratio of the unevenness height h of the metal plate to the wave width W, the larger the flow path area of the laminated plate component. However, if h / W is increased, the amount of deformation of the thick plate due to processing becomes excessive, and necking or cracking may occur in the metal plate, so that it is not easy to obtain a metal plate having a large h / W.
In addition, the uneven shape of the metal plate is often formed by pressing, but the top end of the convex part and the bottom end of the concave part are overhanged, so the thickness of the original plate is significantly reduced and processing cracks also occur. easy.
On the other hand, for example, a surplus portion is likely to occur in a portion that is not greatly deformed by press working, which may cause buckling or wrinkles. Moreover, it may lead to the crack of a metal plate and generation | occurrence | production of a crack.
In addition, in recent years, not only has the heat exchange capacity improved, but the demand for lighter and more compact heat exchangers has also increased, and the thickness of the metal that constitutes the plate has been on the trend of thinning. The difficulty level is also increasing.

  The present invention has been devised to solve such problems, and a method for producing a metal plate that suppresses a reduction in the plate thickness in the metal plate overhanging process and is less prone to necking, cracking, and excess meat. The purpose is to provide.

  In the manufacturing process of the metal plate, the present inventors calculated the sum of the line lengths of the plurality of recesses and protrusions extending in one direction in the press-formed body, and the line length of the recesses or protrusions in the direction orthogonal to the one direction. It has been found that by optimizing, it is possible to obtain a metal plate that is less prone to necking, cracking, and excess meat.

The present invention provides the following (1) to (6) metal plate production method and (7) use for a plate heat exchanger.
(1) The present invention is a method for producing a metal plate, comprising a step of pressing the original plate of the metal plate n times using a mold (n represents an integer of 2 or more), The sum of the line lengths of the plurality of recesses and projections extending in one direction and having the recesses or projections in the direction orthogonal to the one direction and extending in one direction after n times of pressing is L _n × N _n (L represents the line length per one of the plurality of recesses and projections, N represents the total number of the plurality of recesses and projections), Z represents the line length of the recesses or projections in the orthogonal direction _This is a method for producing a metal plate, in which the original plate is formed with a mold so that the metal plate satisfies the relationship of the following formulas (1) and (2), _{where n} is _n .
0.75 ≦ (L _n−1 × N _n−1 ) / ( L _n × N _n ) ≦ 1.3 Formula (1)
0.75 ≦ Z _n−1 / Z _n ≦ 1.3 Formula (2)

(2) In the present invention, the height of the concavo-convex composed of a plurality of concave portions and convex portions extending in one direction is set to h, and the wave width or the concave portion between the convex portions in the plurality of concave portions and convex portions and the convex portions adjacent thereto. The metal plate manufacturing method of (1), wherein h / W is 0.1 or more and 0.4 or less, where W is the wave width between the adjacent recesses.

(3) In the present invention, the press working is the metal plate manufacturing method according to (1) or (2), which is performed by a bumping motion in which the slide descends while moving up and down a plurality of times from the working start position.

(4) Production of the metal plate according to (3), wherein in the present invention, the number of times C ₁ that the slide moves upward from the processing start position and the number of times C ₂ that the slide moves downward are both even numbers of 4 or more. Is the method.

(5) In this invention, an original plate is a manufacturing method of the metal plate in any one of (1)-(4) which consists of a metal selected from steel, titanium, aluminum, or these alloys.

(6) In this invention, an original plate is a manufacturing method of the metal plate in any one of (1)-(5) which is a ferritic stainless steel plate.

(7) The present invention is the use of a laminated plate component obtained by laminating metal plates produced by any one of the production methods (1) to (6) in a plate heat exchanger.

  ADVANTAGE OF THE INVENTION According to this invention, the metal plate manufacturing method which suppresses the board | plate thickness reduction | decrease in the metal plate overhang | projection process small, and is hard to produce necking, a crack, and the surplus thickness can be provided.

It is a schematic diagram which shows an example of the external appearance of the metal plate manufactured with the manufacturing method of this invention. It is AA sectional drawing of FIG. It is BB sectional drawing of FIG. It is a schematic diagram which shows the uneven | corrugated shape of a press-molded body when it press-molds in multiple steps. It is explanatory drawing which shows the line length calculation method of an uneven | corrugated shape. It is explanatory drawing which shows the line length calculation method of an uneven | corrugated shape. It is a figure for demonstrating a press motion. It is a schematic diagram which shows an example of the plate type heat exchanger. It is a schematic diagram which shows the external appearance of the preliminary press molded object shape | molded by the preliminary press. It is a schematic diagram which shows the external appearance of this press molded object shape | molded by this press. It is the cross-sectional schematic diagram from the X direction of a short side part and the cross-sectional schematic diagram from the Y direction of a long side part in the preliminary | backup press of a present Example and this press. It is a photograph which shows the crack and necking in this press molding. It is a photograph which shows the surplus meat in this press molding.

  Hereinafter, although embodiment of this invention is described, these do not limit this invention.

  The present invention is a method for producing a metal plate, and includes a step of pressing a metal plate original plate n times using a mold (n represents an integer of 2 or more). The metal plate has a plurality of recesses and projections extending in one direction, and recesses or projections in a direction orthogonal to the one direction.

  FIG. 1 is a schematic view showing an example of the appearance of a metal plate manufactured by the manufacturing method of the present invention. The metal plate 10 is formed by pressing a substantially flat original plate (blank) so that a plurality of convex shapes each having a short side portion and a long side portion are formed in parallel as shown in FIG. Further, a concave shape having a short side portion and a long side portion is formed between the convex shape and the convex shape. The some recessed part and convex part which are extended in one direction in the metal plate 10 correspond to a short side part, respectively, as shown in FIG. Moreover, the recessed part or convex part of the direction orthogonal to the said one direction corresponds to a long side part as shown in FIG. Further, as shown in FIG. 1, the direction of cross-sectional view of the plurality of concave portions and convex portions (short side portions) is the X direction, and the concave portion or convex portion (long side portion) in the direction orthogonal to the one direction in which the short side portions extend. The direction in which the section is viewed is the Y direction.

  FIG. 2 is a cross-sectional view taken along the line AA in FIG. 1, and is a view of the short side portion of the metal plate 10 as viewed from the X direction. As shown in FIG. 2, the metal plate 10 has a shape in which wavy irregularities continuously extend in one direction above and below the original plate by forming the original plate by press processing, with reference to the original plate position before the forming processing. You may have. The shapes of the plurality of recesses and projections can be the same. The same shape is preferable in that the metal plate 10 can have uniform unevenness and uniform strength, and in terms of heat exchange and appearance depending on the application. In the present specification, regarding the unevenness, a region recessed downward from the center line 13 in the cross section of the metal plate may be referred to as a “concave portion”, and an upward convex region may be referred to as a “convex portion”. The center line 13 corresponds to a substantially central position of the original plate before press molding. As shown in FIG. 2, the metal plate 10 includes concave portions 11a, 11b,... (Hereinafter collectively referred to as “concave portion 11”) and convex portions 12a, 12b,. Are collectively formed in a wavy pattern.

  In the present invention, the height of the concavo-convex composed of a plurality of recesses and projections extending in one direction is set to h, and the wave width or the recess between the projections in the plurality of recesses and projections and the adjacent projections is adjacent to it. When the wave width between the recesses is W, h / W is preferably 0.1 or more and 0.4 or less. In FIG. 2, the distance between the bottom part b1 of the concave part 11 (for example, the concave part 11a) and the top part b2 of the convex part 12 (for example, the convex part 12b) adjacent to the concave part 11 and the convex part 12 It is good also as the height h of the unevenness | corrugation in. Further, the wave width W between the concave portion 11 (for example, the concave portion 11a) and the concave portion 11 (for example, the concave portion 11b) adjacent thereto, or the convex portion 12 (for example, the convex portion 12a) and the convex portion 12 (for example, the convex portion) adjacent thereto. 12b) is the distance between the bottom b1 of the concave portion 11 (for example, the concave portion 11a) and the bottom b3 of the concave portion 11 (for example, the concave portion 11b) adjacent thereto, or the convex portion 12 (for example, the convex portion 12b). This corresponds to the distance between the apex b2 and the apex b4 of the convex part 12 (for example, the convex part 12a) adjacent thereto. H / W, which is a ratio between the height h of the unevenness and the wave width W, is preferably 0.1 or more and 0.4 or less, and more preferably 0.15 or more and 0.3 or less. When h / W is too small, it tends to be difficult to mold the height h of the unevenness with a sufficient size, and it tends to be difficult to produce a molded product with a predetermined shape. On the other hand, if h / W is too large, the amount of deformation due to processing becomes excessive, and the metal plate tends to be easily necked or cracked.

In FIG. 2, the height h ₁ of the concave portion 11 and the height h ₂ of the convex portion 12 correspond to the distance from the bottom of the concave portion 11 or the top of the convex portion 12 to the center line 13 of the metal plate. It is preferable that h ₁ and h ₂ have the same relationship (h ₁ = h ₂ ), and the height h of the unevenness is the sum of h ₁ and h ₂ . Further, the wave width W ₁ of the concave portion 11 and the wave width W ₂ of the convex portion 12 correspond to the distance seen in the horizontal direction from the vicinity of the inflection point that becomes the boundary between the concave portion 11 and the convex portion 12. W ₁ and W ₂ are preferably equal to each other and have a relationship of W ₁ = W ₂ . Such an equal relationship is preferable in that the metal plate 10 can have a uniform unevenness and a uniform strength, and in terms of heat exchange and appearance, depending on the application.

  FIG. 3 is a cross-sectional view taken along the line BB in FIG. 1 and is a view in which the long side portion of the metal plate 10 is viewed in cross section from the Y direction. As shown in FIG. 3, the metal plate 10 has a convex part 14 that is a long side part, and also has a concave part (not shown). The line length Z from the end portion P of the convex portion 14 to the other end portion Q may be the same as or different from the line length of the concave concave portion. In the metal plate 10, when the height of the convex portion 14 that is the long side portion is higher than the height of the concave portion that is the long side portion, the line length Z of the convex portion 14 that is the long side portion is the long side. It becomes longer than the line length of the recessed part of a part. Here, the above-mentioned “line length” means a length (perimeter) along the concavo-convex shape of the metal plate.

  The material of the metal plate is not particularly limited, but steel, titanium, aluminum, or an alloy thereof is used in that it has a high base metal strength and has sufficient pressure resistance even when the metal plate is thin. A metal material selected from is preferred. In particular, stainless steel having excellent corrosion resistance is preferable.

  As the metal plate, stainless steel having a composition defined by JIS or the like can be used. Ferritic (α) stainless steel, austenitic (γ) stainless steel, martensitic stainless steel, or duplex stainless steel can be used. For example, when the height h of the unevenness of the metal plate is increased, an austenitic (γ-based) stainless steel is preferable, and a ferrite single-phase (α-based) stainless steel is preferable in terms of cost.

  And since the metal plate manufactured with the manufacturing method of this invention has a favorable characteristic regarding weight reduction, compactization, heat exchange performance, etc., it can be used for heat exchangers, such as a plate type heat exchanger. Moreover, it is preferable to use a laminated plate component by stacking a plurality of sheets. The metal plates can be joined using fixing means such as welding, diffusion joining, caulking, or bolt fastening. This laminated plate part is preferably applied to a plate heat exchanger.

<Production method of metal plate>
The method for producing a metal plate of the present invention comprises a step of pressing a metal plate original plate n times using a mold (n represents an integer of 2 or more),
The total of the line lengths of the plurality of recesses and projections extending in one direction after n times of pressing is _expressed as L _n × N _n (L represents the line length per one of the plurality of recesses and projections, and N is a plurality of Represents the total number of recesses and protrusions), when the line length of the recesses or protrusions in the orthogonal direction is Z _n ,
This is a method for manufacturing a metal plate, in which the original plate is formed with a mold so that the metal plate satisfies the relationship of the following formulas (1) and (2).
0.75 ≦ (L _n−1 × N _n−1 ) / ( L _n × N _n ) ≦ 1.3 Formula (1)
0.75 ≦ Z _n−1 / Z _n ≦ 1.3 Formula (2)

“ ( L _n−1 × N _n−1 ) / ( L _n × N _n ) ” in the above formula (1) is the total of the line lengths of the plurality of concave portions and convex portions in one direction after n times. The ratio of L _n-1 × N _n-1 which is the sum of the line lengths of the concave and convex portions in one direction after n-1 times to _n × N _n , and the metal plate when viewed in cross section from the X direction The increase / decrease in the line length in the shaping | molding stage of 10 several short side parts is shown.
Moreover, "Z _{n-1 /} Z _n" in the above formula (2) is for the line length Z _n recesses or protrusions in the direction perpendicular to the one direction after n times, the direction orthogonal after n-1 times The ratio of the line length Z _n-1 of the concave portion or the convex portion is shown, and the increase or decrease of the line length in the forming stage of the long side portion of the metal plate 10 when viewed in cross section from the Y direction is shown.
In the production method of the present invention, “(L _n−1 × N _n−1 ) / ( L _n × N _n ) ” is 0.75 or more and 1.3 or less, and “Z _n−1 / Z _By forming with a mold so that “ _n ” is not less than 0.75 and not more than 1.3, a reduction in the plate thickness at the top end of the convex portion and the bottom end of the concave portion of the metal plate is suppressed, and the processing height h It is possible to produce a metal plate that has a high / W and is less prone to necking, cracking, and excess meat.

“ ( L _n-1 × N _n-1 ) / ( L _n × N _n ) ” is an index that is mainly an index that suppresses reduction in thickness, necking, cracking, and surplus of the long side portion. 80 or more is preferable, 0.85 or more is more preferable, and 0.90 or more is more preferable. Moreover, 1.24 or less is preferable, 1.20 or less is more preferable, and 1.15 or less is further more preferable.

“Z _n-1 / Z _n ” is preferably 0.82 or more, and more preferably 0.85 or more, mainly from the viewpoint of an index for suppressing reduction in plate thickness, necking, cracking, and surplus of the short side portion. 0.90 or more is more preferable. Moreover, 1.22 or less is preferable, 1.20 or less is more preferable, 1.15 or less is further more preferable.

  In the method for producing a metal plate of the present invention, the original plate is press-molded in a plurality of times to form an uneven shape. For example, as shown in FIG. 4, a concavo-convex portion formed of a concave portion and a convex portion is formed on the original plates 10 ′ and 10 ″ by press molding in a plurality of steps including a preliminary press and a main press, and the concavo-convex portion is repeated. Press work is performed. In such press working, it is possible to increase the number of concave portions and convex portions while maintaining the overall line length in the horizontal direction when the concave and convex portion is viewed in cross section. Here, the above-mentioned “line length” means a length (perimeter) along the concavo-convex shape of the metal plate.

For example, as shown in FIG. 4, when the original plate 10 ′ is press-molded in two steps in two steps, that is, the preliminary press and the main press, the number of irregularities of the press-formed body is increased by the main press molding. The first convex portion 12 ′ (12a ′, 12b ′,...) And the first concave portion 11 ′ (11a ′, 11b ′,...) And the first concave portion 11 ′ (11a ′, 11b ′,...) Of the press-molded body formed in the first (first step) preliminary pressing step. the total number of ...) and N _1, the length of one per the first protrusion 12 'and the first recess 11' (line length) and L _1, this press second (second step) Of the second convex portion 12 ″ (12a ″, 12b ″,...) And the second concave portion 11 ″ (11a ″, 11b ″,...) Of the press-formed body formed in the process. When the total number is N ₂ and the length (line length) of each of the second convex portion 12 ″ and the second concave portion 11 ″ is L ₂ , L ₁ × N ₁ = L ₂ × N It is particularly preferable to perform press molding so as to be ₂ . When the convex portions and the concave portions are formed so as to have substantially the same shape and size, the line length L ₁ or L ₂ per piece is particularly preferable because the length is substantially uniform over the entire length of the uneven portion. . Moreover, when the line length which is the length per one recessed part or convex part differs individually, the total line length is calculated by calculating the average line length which is the average of the line length of each recessed part or convex part. Can be obtained.

FIG. 4 shows an example in which L ₁ × 7 = L ₂ × 21. That is, the first convex portion 12a ′ in the preliminary pressing step is formed by the press forming in the main pressing step so as to be roughly the three irregularities 12a ″, 11a ″, and 12b ″. the length of the protrusions 12a 'L ₁ is approximately equivalent to a second three minute length of the convex portion length L ₂ of the pressing step. The total number of convex portions and concave portions (N ₁ ) in the preliminary pressing step is 7, and the length per convex portion and concave portion is L ₁ . The total number of convex portions and concave portions (N ₂ ) in this pressing step is 21, and the length per piece is L ₂ . These relationships are shown as L ₁ × 7 = 3L ₂ × 7 = L ₂ × 21.

Further, when the original plate is press-molded in n times, the number of n-th convex portions and n-th concave portions (not shown) of the press-formed body formed by the n-th (n-th step) press molding is the same. When the total is N _n and the length of each n-th convex portion is L _n , L ₁ × N ₁ = L ₂ × N ₂ = L _n × as in the press molding by the above two steps. as will become n _n, it is particularly preferred to press-mold the original plate. For example, when producing a press-molded body having a shape with a large number of irregularities, a shape with a large curvature radius of the irregularities, etc., the press molding can be performed a plurality of times. In order to prevent wrinkling and cracking in the press-formed product, it is preferable to perform press molding twice or three or more times according to the thickness of the original plate and the type of the plate material to deform the original plate stepwise. .

The molding conditions of the above L ₁ × N ₁ = L ₂ × N ₂ = L _n × N _n are a plurality of press moldings within the range of the overall line length in the horizontal direction of the concavo-convex portion of the press molded product. It can be realized by repeating. The overall line length by the press molding in the first step, the overall line length by the press molding in the second step, and the overall line length by the press molding in the nth step are substantially equal to each other, and the press molding is repeated, Each time, it is preferable that the number of convex portions and concave portions in the press-molded body is increased and the processing height h is reduced. Therefore, it may be formed so that the height h of the unevenness is gradually reduced. As shown in FIG. 4, the height h of the unevenness in the press-formed body may be a height based on a horizontal end portion where no unevenness is formed.

Further, in the press-formed body, the radius of curvature of the top portion of the first convex portion 12 ′ (or the bottom portion of the first concave portion 11 ′) is R _L1, and the top portion (or the second concave portion 11 ″ of the second convex portion 12 ″). The base plate is preferably press-molded such that R _L1 > R _L2 > R _Ln, where R _L2 is the radius of curvature of the bottom portion of R) and R _Ln is the radius of curvature of the top of the nth convex portion. In order to increase the surface area of the metal plate, it is preferable to reduce the radius of curvature of the uneven portion as much as possible. However, if an attempt is made to match the target radius of curvature in the first press forming, depending on the press conditions, there may be a region where the reduction in the plate thickness is large in a part of the convex portion 12 or the concave portion 11. Therefore, when the average plate thickness of the original plate is thin, in order to prevent cracking at the convex portion 12 or the concave portion 11, the radius of curvature of the convex portion 12 or the concave portion 11 is reduced stepwise by dividing the press molding into a plurality of times. It is preferable to do.

  In the metal plate manufacturing method of the present invention, it is preferable to use a mold having a structure in which a plurality of convex mold parts and concave mold parts are arranged at predetermined intervals. For example, as shown in FIG. 4, a plurality of convex mold portions are arranged in a protruding manner in accordance with the shapes of the concave portions 11 and the convex portions 12 formed in the press-molded body, and between adjacent convex mold portions. Are lined with concave parts. Two molds having such a shape are combined as, for example, an upper mold 16a and a lower mold 16b in the preliminary press, and an upper mold 17a and a lower mold 17b in the main press, and a workpiece to be pressed between both molds. It is preferable that press molding is carried out after arranging. When the convex part of the mold enters the concave part, the original plate is formed into an uneven shape, and a press-formed body having a predetermined shape is obtained. The height of the convex mold part is set in accordance with the height of the concavo-convex processed part of the press-molded body, but is preferably twice or more higher than the height of the concave part and the convex part. In addition, since the clearance of the thickness of the original plate is required when entering the convex portion and the concave portion, the width of the convex portion is preferably smaller than the width of the concave portion. FIG. 4 shows a mode in which the number of convex portions of the lower mold is one more than the number of convex portions of the upper mold, but a mode of having one convex portion of the upper mold is also possible.

  Although the arrangement of the original plate is not particularly limited, in order to reduce the thickness reduction amount at the top of the convex portion 12 and the bottom portion of the concave portion 11, when the original plate is a stainless steel plate, the convex portion 12 and the concave portion 11 The original plate is preferably arranged so that the longitudinal direction (for example, the center line 13) and the rolling direction of the original plate are perpendicular to each other.

Moreover, as shown in FIG. 3, the recessed part 11 or the convex part 12 is exhibiting the curved surface which the unevenness | corrugation continued in one direction. When these concave portions 11 or convex portions 12 are viewed in a cross-section in a direction orthogonal to the one direction, a curved shape having a radius R _S is formed at the end of the concave portion 11 or the convex portion 12. As shown in FIG. 3, the cross section of the end portion having the R _S also corresponds to the cross section of the short side portion. Therefore, the R _S may be hereinafter referred to as a “short side radius”. Since _RS is 3.0 mm or more, sufficient overhang processability can be obtained, which is preferable.

Further, when the concave portion 11 or the convex portion 12 is viewed in a cross section in the one direction, a curved shape with a radius _RL is formed at the top portion of the concave portion 11 or the convex portion 12, that is, the wave front end portion. As shown in FIG. 4, the cross section of the wave front end portion having the _RL corresponds to the cross section of the long side portion, and therefore, the _RL may be hereinafter referred to as a “long side portion radius”.

5 and 6 are explanatory diagrams showing a method for calculating the line length of the concavo-convex shape. As shown in FIG. 5, the line length of the concavo-convex portion can be calculated based on a shape obtained by adding the ½ shape of the concave portion and the ½ shape of the convex portion. In FIG. 5, the line length L of the concavo-convex portion is a neutral axis that connects the centers in the thickness direction of the original plate, and is obtained as the sum of L _a , L _b , and L _c . α is a wave angle. Further, when the shoulder radii R ₁ and R ₂ are increased, the arc lengths L _a and L _c are also increased, the length of the straight line portion L _b of the line length L is shortened, and the straight line portion L _b may be lost. .
Individual calculation formulas of L _a , L _b , and L _c are expressed as the following formulas (3) to (5).
L _a = (R ₁ + 0.5t) α Formula (3)
L _c = (R ₂ + 0.5t) α Formula (4)

Since the line length L is the sum of L _a , L _b , and L _c , it is expressed by the following formula (6).

FIG. 6 shows how to obtain the line lengths of a plurality of recesses and projections extending in one direction and the line length of the projections in the direction orthogonal to the one direction in the first step or the second step of the pressing step. Show. The line lengths L _T1 and L _T2 of the plurality of concave portions and convex portions extending in one direction are expressed by the following formulas (7) and (8). The uneven shape is a symmetrical shape.

Further, the line lengths Z _T1 and Z _T2 of the convex portions in the orthogonal direction are expressed by the following equations (9) and (10). The uneven shape is a symmetrical shape.

The viscosity of the lubricating oil is not particularly limited, but the kinematic viscosity coefficient at 40 ° C. of the lubricating oil is 50 mm ² / s in order to reduce the thickness reduction amount at the bottom of the recess 11 and the top of the protrusion 12. preferably or more, it is preferably 100 mm ² / s or more, particularly preferably 500 mm ² / s or more. If the kinematic viscosity coefficient of the lubricating oil is too low, the plate thickness at the top of the convex portion 12 and the bottom of the concave portion 11 may be greatly reduced during press molding.

Further, the upper limit of the kinematic viscosity coefficient is not particularly limited, but considering the workability of press molding, the kinematic viscosity coefficient is preferably 750 mm ² / s or less, and more preferably 600 mm ² / s or less. .

  The press motion is not particularly limited. FIG. 7 shows an example of the press motion. Examples of press motion include link motion, soft touch motion, and bumping motion. Link motion refers to press forming in which the slide speed is reduced to about 1/2 from the machining start position to the bottom dead center, and is characterized by a lower strain rate and inertial force than a general mechanical press motion. is there. Soft touch motion refers to press molding in which the slide is at a constant speed and a low speed from the processing start position to the bottom dead center, and is characterized by a strain rate and inertial force being reduced compared to a link motion. Bumping motion refers to press molding in which the slide descends while moving up and down multiple times from the processing start position, and is characterized by excellent lubricating oil reintroduction effect and strain dispersion effect. In the present invention, it is preferable to employ a bumping motion as the press motion in that the thickness reduction at the top of the convex portion and the bottom of the concave portion can be minimized.

In bumping motion, both the number of times C ₂ move slide upward from the machining starting position count C ₁ and downward movement (in the direction away from the press-formed body) (the direction for pressing the pressed bodies) in an even number of 4 or more Preferably there is. As shown in FIG. 7, even in the process of descending while the bumping motion moves up and down, the slide of the press machine starts the operation from the top dead center and returns to the top dead center through the bottom dead center. to continue. When the total number of C ₁ and C ₂ is an odd number, it means that the slide “stops at the bottom dead center” or “starts from the bottom dead center”. It tends to be difficult. Therefore, it is preferable that the total number of C ₁ and C ₂ is an even number. Further, if C ₁ and C ₂ are too small, it is difficult to reduce the thickness reduction at the top of the convex portion 12 and the bottom of the concave portion 11 of the metal plate 10 because a sufficient number of pressing processes cannot be secured. It tends to be.

<Plate type heat exchanger>
FIG. 8 is a schematic view showing an example of the plate heat exchanger 1 according to the present invention. The plate heat exchanger 1 has a structure in which a plurality of metal plates 10 are stacked. The metal plate 10 is sandwiched between the fixed frame 2 and the movable frame 3 and supported by a guide bar 4 and an upper carrying bar (not shown). And the whole is attached to the support | pillar (illustration omitted), and it tightens with the fastening bolt (illustration omitted).

  The fixed frame 2 is formed with connection ports 8a and 8b into which piping for circulating the high temperature side fluid is inserted and connection ports 9a and 9b into which piping for circulating the low temperature side fluid is inserted. The metal plate 10 is also provided with an opening through which the high temperature side fluid and the low temperature side fluid pass. The metal plate 10 is formed with corrugations and hemispherical irregularities. As shown in FIG. 8 (b), the high temperature fluid and the low temperature fluid alternate with each other in the gap between the stacked metal plates 10. A flow path is formed so as to flow through. Thereby, heat is exchanged between the high temperature side fluid and the low temperature side fluid via the individual metal plates 10.

Although the case where the adjacent metal plates 10 are joined by bolt fastening has been described with reference to FIG. 8, the manner of joining is not limited to this. For example, the adjacent metal plates 10 may be joined by welding, diffusion bonding, brazing, caulking, or the like. Especially, it is preferable that the adjacent metal plate 10 is joined by brazing from the defect and strength surface of a junction part at the point which is excellent in pressure | voltage resistance and leak resistance.
In addition, a steel type in which corrosion resistance and workability are improved by adding Ti and Nb is used for stainless steel for the purpose of trapping free C and N, which cause deterioration of corrosion resistance and workability. Since Ti becomes an impediment to brazing, SUS430J1L with Nb added is superior to other ferritic stainless steels with Ti addition or Ti + Nb composite addition, and is brazed. Preferred as a steel type.

  Hereinafter, although the present invention is explained still in detail using an example, the present invention is not limited to these.

(Original plate)
As the original plate, a ferritic stainless steel plate (manufactured by Nisshin Steel Co., Ltd.) having the component composition shown in Table 1 below and the mechanical properties shown in Table 2 was used. The unit of Table 1 is mass%.

[First press molding (preliminary press)]
About the said original plate, the first press molding (preliminary press) is performed on the following conditions, and as shown in FIG. 9, the preliminary press molding 10a which has a total of seven convex parts and three concave parts as a short side part. Got. Moreover, press molding was performed so that the uneven height of the preliminary press-molded body 10a was 7 mm, with the uneven height of the present pressed body being 2.5 mm as a target value. The uneven height and line length of the pre-pressed product and the main press-formed product are detected by detecting the outer shape of the molded product with a contact-type contour measuring instrument (manufactured by Mitutoyo Corporation, model number: CONTRACER CV-2000). Measurements were made by using instrument analysis software.

(Preliminary press conditions)
Rolling direction of test material: D direction (long side longitudinal direction and rolling direction of original sheet are 45 °)
Equipment: 80ton servo press Processing speed: 10 (spm)
Lubrication conditions: Press oil G-755BM (viscosity at 40 ° C .: 564 mm ² / s, manufactured by Nippon Tool Oil Co., Ltd.)
Press motion: Link motion Uneven wave width W: 21 mm
Unevenness height h: 7 mm (target value)
h / W: 0.33
Board presser dimensions: 180mm x 180mm (with square bead)
Blank dimensions: □ 120mm
Plate holding force: 6.3 ton

[Second press forming (main press)]
The preliminary press-molded body 10a obtained by the first press molding (preliminary press) is press-molded under the following conditions, and the press-molded body 10b (11 convex portions and 10 concave portions) shown in FIG. A total of 21) was obtained.

(This press condition)
Rolling direction of test material: D direction (long side longitudinal direction and rolling direction of original sheet are 45 °)
Equipment: 80ton servo press Processing speed: 10 (spm)
Lubrication conditions: Press oil G-755BM (viscosity at 40 ° C .: 564 mm ² / s, manufactured by Nippon Tool Oil Co., Ltd.)
Press motion: Link motion Uneven wave width W: 7mm
Unevenness height h: 2.5 mm (target value)
h / W: 0.36
Board presser dimensions: 180mm x 180mm (with square bead)
Blank dimensions: □ 120mm
Plate holding force: 6.3 ton

  FIG. 11 shows a cross section from the X direction of the short side portion and a cross section from the Y direction of the long side portion of the pre-press formed body 10a in FIG. 9 and the present press molded body 10b in FIG. As shown in FIG. 11, the height of the press-molded body was changed from 7 mm to 2.5 mm from the preliminary press to the main press, but the line length of the short side part and the line length of the long side part were both 84 mm. It is shown that.

Using various molds with different shape parameters, the preliminary press and the main press are repeatedly performed to produce a plurality of preliminary press molded bodies and the main press molded bodies having a predetermined shape and dimensions. “ ( L ₁ × N ₁ ) / ( L ₂ × N ₂ ) ” which is the ratio of the line lengths of the side portions and “Z ₁ / Z ₂ ” which is the ratio of the line lengths of the long side portions were measured.

(Evaluation index)
The molding condition of the molded press molded body was evaluated according to the following criteria. If the evaluation index is "△", "○", "□", it can be used as a metal plate, and if it is "x", "black paint △", "black paint □", it can be used as a metal plate ( (See FIGS. 12 and 13).
×: Black coating with cracks Δ: Necking (deformation of appearance) Δ: Plate thickness reduction rate is 25% or more and less than 30% ○: Good (plate thickness reduction rate is less than 25%)
□: There is a surplus but there is little black □: There is a lot of surplus-: There is no corresponding molded product

  FIG. 12 is a diagram showing states such as cracking and necking in the press-formed body. (A) of FIG. 12 is an example of “x” indicating that the end portion of the short side portion is cracked due to an increase in the plate thickness reduction rate or the like. (E) of FIG. 12 is an example of “x” indicating that the long side portion is cracked. FIG. 12B is an example of “black paint Δ” indicating that the end of the short side portion has been deformed and necking has occurred. When necking occurs, the plate thickness reduction rate is considered to be about 30% to 40%. (F) of FIG. 12 is an example of “black painting Δ” indicating that necking has occurred in the long side portion. (C) of FIG. 12 is an example of “Δ” indicating that the thickness reduction rate at the end of the short side is 25% or more and less than 30%. (G) of FIG. 12 is an example of “Δ” indicating that the plate thickness reduction rate of the long side portion is 25% or more and less than 30%. (D) of FIG. 12 is an example of “◯” indicating a good state in which no cracking or necking occurs at the end of the short side. (H) of FIG. 12 is an example of “◯” indicating a good state in which no cracks or necking occurs in the long side portion.

  The plate thickness reduction rate can be measured with a length meter after cutting the vicinity of the measurement portion by wire processing and photographing the cross-sectional portion.

FIG. 13 is a diagram showing a state of excess meat in the press-formed body. (A) of FIG. 13 is an example of “◯” indicating a good state in which no surplus portion is generated at the end portion of the short side portion. (D) of FIG. 13 is an example of “◯” showing a good state in which no surplus portion is generated in the long side portion. FIG. 13B is an example of “□” indicating that a surplus has occurred at the end of the short side. Moreover, (e) of FIG. 13 is an example of “□” indicating that a surplus has occurred at the end of the long side. As shown in (b) and (e) of FIG. 13, even if a surplus occurs, if the surplus portion can be corrected by further pressing, it was determined that “the surplus surplus”.
On the other hand, (c) of FIG. 13 is an example of “black □” which indicates that excessive surplus has occurred at the end of the short side. FIG. 13 (f) is an example of “black □” indicating that excessive surplus has occurred at the end of the long side. As shown in FIG. 13C, for example, when the end is folded, or when buckling or wrinkle occurs as shown in FIG. Is difficult, it was determined that “there is much excess meat”.

  The measurement results and evaluation results are shown in Table 3 below. In addition, when “L” is written in the right corner of each evaluation index, it indicates that the evaluation is performed on the short side portion. Further, when “Z” is added to the right corner of each evaluation index, it indicates that the evaluation is for the long side portion.

As shown in Table 3, “ ( L ₁ × N ₁ ) / ( L ₂ × N ₂ ) ”, which is a ratio of the total line lengths of the short side portions of the pre-press formed body and the present press formed body, is 0.75 When “Z ₁ / Z ₂ ” which is the ratio of the line length of the long side portion is not less than 1.3 and not more than 1.3 and is not less than 0.75 and not more than 1.3, “Δ”, “□” The evaluation was either “◯”, and it was confirmed that even if the processing height h / W was high, a reduction in the plate thickness was suppressed, and a metal plate that could hardly cause necking, cracking, and excess meat could be produced. In particular, “ ( L ₁ × N ₁ ) / (L ₂ × N ₂ ) ” is in the range of 0.91 to 1.13, and “Z ₁ / Z ₂ ” is in the range of 0.91 to 1.12. In this case, it was shown that a metal plate in which the evaluation of both the short side portion and the long side portion was good was obtained.

On the other hand, as shown in Table 3, when “ ( L ₁ × N ₁ ) / (L ₂ × N ₂ ) ”, which is the ratio of the total line lengths of the short sides, is as low as 0.62, “Z _In the range of “ ₁ / Z ₂ ” from 0.61 to 1.52, cracks occurred at the long side portion. In addition, even when “ ( L ₁ × N ₁ ) / (L ₂ × N ₂ ) ” was 0.71, necking occurred at all long sides. In addition, when “ ( L ₁ × N ₁ ) / (L ₂ × N ₂ ) ” was 1.31 or more, the result was that the surplus portion was increased in the long side portion.

Further, as shown in Table 3, when “Z ₁ / Z ₂ ”, which is the ratio of the line lengths of the long side portions, was as low as 0.61, all the short side portions were cracked. In addition, when “Z ₁ / Z ₂ ” was 1.32 or more, the result was that the surplus portion increased in all of the short sides.
Although the said Example is a test example at the time of performing press molding twice, it confirmed that the same effect was acquired even when press molding was performed 3 times or more.

DESCRIPTION OF SYMBOLS 1 Plate type heat exchanger 2 Fixed frame 3 Movable frame 4 Guide bar 5 Upper carrying bar 6 Post 7 Tightening bolt 8a, 8b High temperature side fluid piping connection port 9a, 9b Low temperature side fluid piping connection port 10 Metal plate 11 Short side Concave part 12 Short side convex part 13 Center line 14 Long side convex part 16a, 16b Upper part and lower part of mold A 17a, 17b Upper part and lower part of mold B

Claims (7)

A method of manufacturing a metal plate, comprising:
A step of pressing the original plate of the metal plate n times using a mold (n represents an integer of 2 or more);
The metal plate has a plurality of recesses and projections extending in one direction, and a recess or projection in a direction orthogonal to the one direction,
L _n × N _n (L represents the line length per one of the plurality of recesses and projections, and Represents the total number of the plurality of recesses and projections), when the line length of the orthogonal recesses or projections is Z _n ,
A method for producing a metal plate, wherein the original plate is formed with the mold so that the metal plate satisfies the relationship of the following formulas (1) and (2).
0.75 ≦ (L _n−1 × N _n−1 ) / ( L _n × N _n ) ≦ 1.3 Formula (1)
_{0.75 ≦ Z n-1 / Z} n ≦ 1.3 Equation (2)   The height of the concavo-convex formed by the plurality of concave portions and convex portions extending in one direction is h, and the wave width or the concave portion between the convex portions and the convex portions adjacent thereto in the plural concave portions and convex portions, and the concave portions adjacent thereto. The metal plate manufacturing method according to claim 1, wherein h / W is 0.1 or more and 0.4 or less, where W is the wave width between the two.   The said press work is a manufacturing method of the metal plate of Claim 1 or 2 performed by the bumping motion to which a slide descend | falls, moving up and down several times from a process start position. 4. The method of manufacturing a metal plate according to claim 3, wherein the number of times C _{1 in which} the slide moves upward from the processing start position and the number of times C _{2 in} which the slide moves downward are both even numbers of 4 or more.   The said original plate is a manufacturing method of the metal plate as described in any one of Claims 1-4 which consists of a metal selected from steel, titanium, aluminum, or these alloys.   The said original plate is a manufacturing method of the metal plate as described in any one of Claims 1-5 which is a ferritic stainless steel plate. Use of a laminated plate component obtained by laminating metal plates produced by the production method according to any one of claims 1 to 6 in a plate heat exchanger.