JP2769352B2 - Manufacturing method of thin flat tube - Google Patents
Manufacturing method of thin flat tubeInfo
- Publication number
- JP2769352B2 JP2769352B2 JP1103992A JP10399289A JP2769352B2 JP 2769352 B2 JP2769352 B2 JP 2769352B2 JP 1103992 A JP1103992 A JP 1103992A JP 10399289 A JP10399289 A JP 10399289A JP 2769352 B2 JP2769352 B2 JP 2769352B2
- Authority
- JP
- Japan
- Prior art keywords
- tube
- flat
- flat tube
- manufacturing
- section
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Description
【発明の詳細な説明】 産業上の利用分野 この発明は、自動車のラジエータ用チューブ、ヒータ
ーコア用チューブ等に使用されるようなアルミニウム等
の金属材料よりなる薄肉扁平チューブの製造方法に関す
る。Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a thin flat tube made of a metal material such as aluminum used for a radiator tube, a heater core tube and the like of an automobile.
なお、この明細書において使用される「アルミニウ
ム」の語は、その合金を含む意味において用いられる。Note that the term “aluminum” used in this specification is used to include its alloy.
従来の技術 この種の薄肉扁平チューブは、これまで主として高周
波接合法とロールフォーミング法との組合わせによる電
縫管として製造されていた。2. Description of the Related Art A thin flat tube of this type has been manufactured as an electric resistance welded tube mainly by a combination of a high frequency bonding method and a roll forming method.
ところで、最近では、チューブの軽量化、性能向上等
を図るために、一層の薄肉化が要請され、0.15〜0.2mm
の超薄肉の扁平チューブの製造も検討されるようになっ
ている。このような超薄肉扁平チューブの製造方法とし
ては、（イ）従来の高周波接合法とロールフォーミング
法との組合わせによって電縫管として製造する方法、
（ロ）押出丸パイプを引抜きにより薄肉化する方法、等
が考えられる。By the way, recently, in order to reduce the weight and improve the performance of the tube, further thinning is demanded, and 0.15 to 0.2 mm
The production of ultra-thin flat tubes is also being considered. As a method of manufacturing such an ultra-thin flat tube, (a) a method of manufacturing an electric resistance welded tube by a combination of a conventional high-frequency bonding method and a roll forming method;
(B) A method of drawing out an extruded round pipe to make it thinner can be considered.
発明が解決しようとする課題 ところが、上記（イ）の電縫管として製造する方法に
おいては、超薄肉の素材に対する高周波接合の安定実施
が困難であること、素材の突合せ部に段差を生じ易く、
得られた接合部に漏れ等の原因となる品質的な欠陥が発
生する危険性が高いこと、高周波接合法による場合は本
来的に接合部の耐食性に問題があるが、薄肉化に伴いそ
の問題が一層顕著なものとなり、接合部の耐食信頼性が
極めて低いものとなること、また管壁の薄肉化をせいぜ
い0.3mm程度までしか実現しえないこと、等の問題があ
る。Problems to be Solved by the Invention However, in the method for producing an electric resistance welded pipe of the above (A), it is difficult to stably perform high-frequency joining to an ultra-thin material, and a step is easily generated in a butt portion of the material. ,
There is a high risk that quality defects that cause leakage etc. will occur in the obtained joint, and the high frequency joining method inherently has a problem with the corrosion resistance of the joint, but with the thinning, the problem Are more remarkable, there is a problem that the corrosion resistance of the joint is extremely low, and the wall thickness of the pipe wall can be reduced to about 0.3 mm at most.
一方、上記（ロ）の引抜法による場合は、押出によっ
て製造できる丸パイプの肉厚はせいぜい0.4mmで、これ
を0.15〜0.2mmの厚さにまで引抜くには多くのパス数
（通常は５〜７）が必要となり、しかも各パスごとにパ
イプに加工硬化が惹起されるのでそれに対処すべく繰返
し焼鈍処理を実施する必要があり、結果的に製造コスト
の大幅な上昇を招くという問題がある。因みに、試算に
よると、前記電縫管として製造する方法に比べ約20倍も
のコスト高となる。On the other hand, in the case of the drawing method of (b) above, the thickness of a round pipe that can be produced by extrusion is at most 0.4 mm, and a large number of passes (usually, 5 to 7) are required, and work hardening is caused in the pipe at each pass, so that it is necessary to repeatedly perform annealing treatment to cope with the hardening, and as a result, the production cost is significantly increased. is there. By the way, according to the trial calculation, the cost is about 20 times higher than the method of manufacturing the electric resistance welded pipe.
この発明は、上記のような従来の欠点を解消すべく、
特に超薄肉の扁平チューブを高品質にかつ低コストにて
製造しうる薄肉扁平チューブの製造方法を提供すること
を目的とする。The present invention has been developed to solve the above-mentioned conventional disadvantages.
In particular, an object of the present invention is to provide a method for manufacturing a thin-walled flat tube capable of manufacturing an ultra-thin flat tube with high quality at low cost.
課題を解決するための手段 上記目的を達成するために、この発明は、押出加工に
よって所定肉厚を有するものに形成されたアルミニウム
等の金属材料よりなる断面円形の押出管を素材として用
い、該素材を断面扁平板状に圧潰しかつ管壁が所定肉厚
に減少されるまで圧延したのち、得られた板状圧延管材
をその内部に流体圧を導入することによって断面円形に
膨管し、次いでロールフォーミング加工を施すことによ
り両側部に外方突出状の耳部を残在せしめた所定の求め
る扁平管形状に成形することを特徴とする薄肉扁平チュ
ーブの製造方法を要旨とする。Means for Solving the Problems In order to achieve the above object, the present invention uses an extruded tube having a circular cross section made of a metal material such as aluminum formed into a material having a predetermined thickness by extrusion, as a material. After crushing the material into a flat cross section and rolling until the tube wall is reduced to a predetermined thickness, the obtained plate-like rolled tubing is expanded into a circular cross section by introducing fluid pressure into the inside, Next, the gist of the present invention is a method of manufacturing a thin flat tube, which is formed into a predetermined flat tube shape desired by leaving a protruding lug on both sides by roll forming.
実施例 以下、この発明の薄肉扁平チューブの製造方法を図示
実施例に基づいて説明する。EXAMPLES Hereinafter, a method for manufacturing a thin flat tube according to the present invention will be described based on illustrated examples.
第１図に示されるように、この製造方法は、 （ｉ）押出加工によって所定肉厚を有するものに形成さ
れたアルミニウム等の金属材料よりなる同図（イ）に示
されるような断面真円形の押出管（１）を素材として用
い、該押出管（１）を断面扁平板状に圧潰しかつその管
壁が所定肉厚に減少されるまで圧延することによって同
図（ロ）に示されるような板状圧延管材（２）に加工す
る圧潰・圧延工程と、 （ii）該板状圧延管材（２）をその内部に流体圧を導入
することによって同図（ハ）に示されるような断面真円
形の膨管材（３）に膨管する膨管工程と、 （iii）該膨管材（３）にロールフォーミング加工を施
すことにより同図（ニ）に示されるような扁平チューブ
（４）に成形する成形工程 とによって構成されている。As shown in FIG. 1, this manufacturing method comprises the following steps: (i) A cross-section of a perfect circular shape as shown in FIG. (B) by using the extruded tube (1) as a raw material, crushing the extruded tube (1) into a flat cross section and rolling until the tube wall is reduced to a predetermined thickness. (Ii) a crushing / rolling step of processing into such a plate-shaped rolled tube (2), and (ii) by introducing a fluid pressure into the plate-shaped rolled tube (2). (Iii) a flat tube (4) as shown in FIG. 3 (d) by subjecting the expanded tube (3) to roll forming to expand the expanded tube (3) having a perfectly circular cross section; And a forming step of forming into a.
上記において、押出管（１）の肉厚t0は例えば0.4〜
0.3mmである。かゝる押出管（１）は、第２図に示され
るように、所定の押出機（５）から上記肉厚t0を有する
ものに押出され、該押出機（５）の前方位置においてコ
イル状（６）に捲回される。In the above, the thickness t 0 of the extruded tube (1) is for example 0.4
0.3 mm. Such extruded tube (1), as shown in Figure 2, is extruded predetermined extruder from (5) to those having the thickness t 0, the coil in front of the extruder (5) It is wound in shape (6).
上記圧潰・圧延工程で得るべき板状圧延管材（２）の
管壁の肉厚t1は例えば0.1〜0.2mmである。かゝる板状圧
延管材（２）は、第３図に示されるように、前記押出管
（１）を圧潰・圧延用ロール群（７）に通して上記肉厚
t1に圧延し、該ロール群（７）の前方位置においてコイ
ル状（８）に捲回される。ここに、得られた板状圧延管
材（２）の両側縁には、第１図（ロ）に部分拡大によっ
て示されるように、板厚の中間に合わせ面をもたない外
方突出状の耳部（９）（９）が形成される。これは、圧
潰によって折返し状態にされた両側縁部が圧延に付され
ることにより外方に延伸されることによる。この耳部
（９）（９）の幅ａは例えば管壁の肉厚t1の２〜2.5倍
である。Thickness t 1 of the tube wall of the plate-shaped rolled tubing to be obtained by the above crushing-rolling step (2) is 0.1~0.2mm example. As shown in FIG. 3, the plate-like rolled tube material (2) passes the extruded tube (1) through a group of crushing / rolling rolls (7) and has the above thickness.
rolled to t 1, it is wound into a coil (8) at the forward position of the rolls (7). Here, as shown by partial enlargement in FIG. 1 (b), outwardly projecting shapes having no mating surface in the middle of the sheet thickness are provided on both side edges of the obtained sheet-like rolled tube material (2). Ears (9) and (9) are formed. This is because both side edges turned into a folded state by crushing are stretched outward by being subjected to rolling. Width a is 2 to 2.5 times the example tube wall thickness t 1 of the ear portion (9) (9).
上記膨管工程は、第４図に示されるように、板状圧延
管材（２）の一端から内部に例えば空気等の気体、ある
いは水、油等の液体を高圧状態で導入することにより行
う。なお、膨管を行う場合、一般に同図に示されるよう
な圧力遮断用ロール（10）が使用される。この圧力遮断
用ロール（10）は板状圧延管材（２）の中途部を閉塞す
るもので、該ロール（10）によって、管内の流体圧がロ
ール（10）と流体導入部との間の空間に集中されるもの
となり、もって板状圧延管材（２）を所期するところの
断面真円形に確実に膨管しうるものとなる。なお、得ら
れた膨管材（３）はコイル状（11）に捲回される。ここ
に、前記板状圧延管材（２）の両側縁に形成された耳部
（９）（９）は膨管による作用を受けないので、第１図
（ハ）に示されるように、結果的に膨管材（３）の両側
部に外方突出状の耳部（９）（９）が残存顕在化され
る。As shown in FIG. 4, the inflating step is performed by introducing a gas such as air or a liquid such as water or oil from one end of the plate-like rolled tube material (2) in a high pressure state. In addition, when performing inflation, a pressure-blocking roll (10) as shown in the figure is generally used. The pressure-blocking roll (10) closes a middle part of the plate-shaped rolled tube (2), and the roll (10) reduces the fluid pressure in the pipe between the roll (10) and the fluid introduction section. Therefore, the plate-shaped rolled tube (2) can be surely expanded to a desired circular cross section at the intended position. The obtained expanded tube material (3) is wound into a coil shape (11). Here, since the lugs (9) (9) formed on both side edges of the plate-like rolled tube (2) are not affected by the expansion tube, as a result, as shown in FIG. Then, outwardly protruding ears (9) (9) remain on both sides of the inflatable material (3).
また、ロールフォーミング加工による上記成形工程
は、第５図に示されるように、複数対前後方向に配設し
た成形用ロール（12）…に前記膨管材（３）を通し、最
終的に例えば幅ｂが13〜16mm、高さｈが1.3〜1.5mmの扁
平チューブ（４）になるように、徐々に扁平化していく
ものである。この過程で管材は加工硬化するものとな
り、得られる扁平チューブ（４）の強度が向上される。
なお、最終の成形用ロール（12）通過後は、適宜切断機
（13）により所定の長さに切断される。また上記膨管材
（３）の両側部における耳部（９）（９）は、そのまま
扁平チューブ（４）の両側部に同様の耳部（９）（９）
として残存させるものとする。In addition, as shown in FIG. 5, in the above-mentioned forming step by roll forming, the expanded tube material (3) is passed through a plurality of forming rolls (12). It is gradually flattened so that b becomes a flat tube (4) having a length of 13 to 16 mm and a height h of 1.3 to 1.5 mm. In this process, the tube material becomes work-hardened, and the strength of the obtained flat tube (4) is improved.
After passing through the final forming roll (12), it is appropriately cut by a cutting machine (13) to a predetermined length. The ears (9) and (9) on both sides of the inflated tube material (3) are similar to the ears (9) and (9) on both sides of the flat tube (4).
It shall be left as.
発明の効果 以上の次第により、この発明の薄肉扁平チューブの製
造方法は、押出加工によって所定肉厚を有するものに形
成されたアルミニウム等の金属材料よりなる断面円形の
押出管を素材として用い、該素材を断面扁平板状に圧潰
しかつ管壁が所定肉厚に減少されるまで圧延したのち、
膨管、成形するものであるから、従来の電縫管に製造す
る方法の場合のような接合部が存在せず、そのため超薄
肉の板状の両側縁を高周波によって接合することに起因
する製品の品質面での問題を生じることがなく、高品質
の超薄肉扁平チューブを製造できる。また同時に、従来
の引抜法におけるような引抜きと焼鈍処理との繰返しに
起因する製造コストの上昇を招くこともなく、低コスト
にて超薄肉扁平チューブの製造を行うことができる。Effect of the invention As described above, the method for manufacturing a thin-walled flat tube of the present invention uses, as a material, an extruded tube having a circular cross section made of a metal material such as aluminum formed into a material having a predetermined thickness by extrusion. After crushing the material into a flat cross section and rolling until the tube wall is reduced to a predetermined thickness,
Since it is an inflated tube, it is molded, there is no joint as in the case of the conventional method for manufacturing an electric resistance welded tube, and therefore, it is caused by joining both side edges of an ultra-thin plate with high frequency. It is possible to manufacture a high-quality ultra-thin flat tube without causing a problem in terms of product quality. At the same time, an ultra-thin flat tube can be manufactured at low cost without increasing the manufacturing cost due to the repetition of drawing and annealing as in the conventional drawing method.
加えて、圧延によって得られた板状圧延管材について
は、まずその内部に流体圧を導入することによって一旦
断面円形に膨管し、次いでロールフォーミング加工を施
すことにより所定の求める扁平管形状に成形するものと
しているから、成形工程において管材に加工硬化が惹起
されるものとなり、従って超薄肉にして高強度の扁平チ
ューブを得ることができる。即ち、板状圧延管材を直接
扁平状に膨管することも考えられるが、完成品の精度、
強度等の観点から必ずしも満足いくものを得ることがで
きないことが実験的に判明しており、かゝる問題点を上
記工程の結合により有効に解決しうる。In addition, the plate-like rolled tube material obtained by rolling is first expanded into a circular cross section by introducing a fluid pressure into the inside, and then formed into a predetermined flat tube shape required by roll forming. Therefore, work hardening is caused in the tube material in the forming step, and therefore, a flat tube having an ultra-thin wall and high strength can be obtained. In other words, it is conceivable to directly expand the plate-like rolled tube material into a flat shape, but the accuracy of the finished product,
It has been experimentally found that it is not always possible to obtain a satisfactory product from the viewpoint of strength and the like, and such a problem can be effectively solved by combining the above steps.
また、従来の方法によって製造された扁平チューブ
は、その上下の管壁を連接する左右両側部が上壁から下
壁へと滑かに大きく湾曲する断面横Ｕ字状管壁となされ
ており、そのためこのチューブを例えば第７図に示され
るように、フィン（54）と組合わせて自動車用ラジエー
タ（51）のチューブ（52）として適用したような場合、
ラジエータ（51）の前面部に上記のようなＵ字状管壁部
（53）が位置するものとなり、これに直接外部からの衝
撃、例えば小石や小枝等が当たると、その衝撃でチュー
ブ（52）そのものが変形したり、甚だしくは管壁が破れ
て孔が開くというような危険性がある。これに対し、本
発明の方法によれば、押出管に対する圧潰・圧延によっ
て得られる板状圧延管材の両側縁に外方突出状の耳部が
延伸形成され、かゝる耳部が後の膨管工程、成形工程を
経たのちもそのまま残存されるので、このようにして製
造された扁平チューブを、例えば第６図に示されるよう
に、フィン（23）と組合わせて自動車のラジエータ用扁
平チューブ（21）として使用した場合、ラジエータ（2
2）の前面部にチューブ（21）の耳部（９）が位置する
ものとなり、これが補強リブとしての役目を示すととも
に、外部衝撃に対するバンパーないしはプロテクターと
しての役目を示すため、前記従来品のようにチューブ
（21）が外的衝撃によって容易に大きく変形したり、ま
たチューブ壁面が破れて孔が開くといった事故の発生を
大幅に減少し、一層耐久性に優れたものとすることがで
きる。In addition, the flat tube manufactured by the conventional method has a horizontal U-shaped tube wall in which the left and right both sides connecting the upper and lower tube walls smoothly and greatly bend from the upper wall to the lower wall, For example, when this tube is combined with a fin (54) and applied as a tube (52) of an automobile radiator (51) as shown in FIG.
The U-shaped pipe wall portion (53) as described above is located on the front surface of the radiator (51). When an external impact such as pebbles or twigs directly hits the tube wall (53), the tube (52) is applied by the impact. There is a danger that the tube itself may be deformed or the pipe wall may be broken and a hole may be opened. On the other hand, according to the method of the present invention, outwardly projecting lugs are formed on both side edges of the plate-shaped rolled tube material obtained by crushing and rolling the extruded pipe, and such lugs are formed to expand later. The flat tube manufactured as described above is left as it is after the tube process and the forming process. For example, as shown in FIG. 6, the flat tube for an automobile radiator is combined with a fin (23) as shown in FIG. When used as (21), the radiator (2
The ear part (9) of the tube (21) is located at the front part of (2), which serves as a reinforcing rib and also serves as a bumper or a protector against external impact. In addition, the occurrence of accidents such as the tube (21) being easily deformed greatly by an external impact and the tube wall being broken and opening a hole is greatly reduced, and the durability can be further improved.
第１図ないし第５図はこの発明の実施例を示すもので、
第１図（イ）〜（ニ）は扁平チューブの各製造工程にお
ける横断面図、第２図は押出工程を示す概略側面図、第
３図は圧潰・圧延工程を示す概略側面図、第４図は膨管
工程を示す概略側面図、第５図は成形工程を示す概略側
面図である。第６図はこの発明方法によって製造された
扁平チューブを適用した自動車用ラジエータの一部を示
す断面図、第７図は従来の扁平チューブを適用した自動
車用ラジエータの一部を示す断面図である。 （１）……押出管（素材）、（２）……板状圧延管材、
（３）……膨管材、（４）……薄肉扁平チューブ。1 to 5 show an embodiment of the present invention.
1 (a) to 1 (d) are cross-sectional views in each manufacturing process of a flat tube, FIG. 2 is a schematic side view showing an extrusion process, FIG. 3 is a schematic side view showing a crushing / rolling process, and FIG. The figure is a schematic side view showing the inflating step, and FIG. 5 is a schematic side view showing the forming step. FIG. 6 is a sectional view showing a part of an automotive radiator to which a flat tube manufactured by the method of the present invention is applied, and FIG. 7 is a sectional view showing a part of an automotive radiator to which a conventional flat tube is applied. . (1) ... extruded tube (material), (2) ... plate-shaped rolled tube,
(3) ... expanded tube material, (4) ... thin flat tube.
Claims (1)
形成されたアルミニウム等の金属材料よりなる断面円形
の押出管を素材として用い、該素材を断面扁平板状に圧
潰しかつ管壁が所定肉厚に減少されるまで圧延したの
ち、得られた板状圧延管材をその内部に流体圧を導入す
ることによって断面円形に膨管し、次いでロールフォー
ミング加工を施すことにより両側部に外方突出状の耳部
を残存せしめた所定の求める扁平管形状に成形すること
を特徴とする薄肉扁平チューブの製造方法。An extruded tube having a circular cross section made of a metal material such as aluminum formed into a material having a predetermined thickness by extrusion processing is used as a material, and the material is crushed into a flat cross section and the pipe wall has a predetermined thickness. After rolling until the wall thickness is reduced, the obtained plate-shaped rolled tube is expanded into a circular cross section by introducing fluid pressure into the inside, and then outwardly projected on both sides by performing roll forming processing A method for producing a thin-walled flat tube, characterized in that the flat-shaped tube is formed into a predetermined desired flat tube shape in which an annular ear portion is left.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1103992A JP2769352B2 (en) | 1989-04-24 | 1989-04-24 | Manufacturing method of thin flat tube |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1103992A JP2769352B2 (en) | 1989-04-24 | 1989-04-24 | Manufacturing method of thin flat tube |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02284715A JPH02284715A (en) | 1990-11-22 |
| JP2769352B2 true JP2769352B2 (en) | 1998-06-25 |
Family
ID=14368795
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1103992A Expired - Lifetime JP2769352B2 (en) | 1989-04-24 | 1989-04-24 | Manufacturing method of thin flat tube |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2769352B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100537127C (en) * | 2007-12-21 | 2009-09-09 | 金龙精密铜管集团股份有限公司 | Production line for metal flat tube and method for manufacturing metal flat tube |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0972680A (en) * | 1995-09-05 | 1997-03-18 | Akutoronikusu Kk | Structure of porous flat tube and manufacture thereof |
| JP2019032119A (en) * | 2017-08-08 | 2019-02-28 | サンデンホールディングス株式会社 | Heat exchanger |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS49135874A (en) * | 1973-05-04 | 1974-12-27 | ||
| JPS5199657A (en) * | 1975-02-28 | 1976-09-02 | Furukawa Electric Co Ltd | USUNIKUCHOJAKUKANNOSEIZOHOHO |
-
1989
- 1989-04-24 JP JP1103992A patent/JP2769352B2/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100537127C (en) * | 2007-12-21 | 2009-09-09 | 金龙精密铜管集团股份有限公司 | Production line for metal flat tube and method for manufacturing metal flat tube |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH02284715A (en) | 1990-11-22 |
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