JPH01192425A - Manufacture of flare tube - Google Patents
Manufacture of flare tubeInfo
- Publication number
- JPH01192425A JPH01192425A JP1562988A JP1562988A JPH01192425A JP H01192425 A JPH01192425 A JP H01192425A JP 1562988 A JP1562988 A JP 1562988A JP 1562988 A JP1562988 A JP 1562988A JP H01192425 A JPH01192425 A JP H01192425A
- Authority
- JP
- Japan
- Prior art keywords
- tube
- frequency coil
- heating
- cycle
- frequency
- 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.)
- Granted
Links
- 238000004519 manufacturing process Methods 0.000 title claims description 12
- 238000010438 heat treatment Methods 0.000 claims abstract description 28
- 239000000110 cooling liquid Substances 0.000 claims abstract description 9
- 238000000034 method Methods 0.000 claims abstract description 8
- 238000001816 cooling Methods 0.000 claims abstract description 6
- 238000000465 moulding Methods 0.000 description 8
- 239000002826 coolant Substances 0.000 description 6
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000001125 extrusion Methods 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000002845 discoloration Methods 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 230000008961 swelling Effects 0.000 description 1
Landscapes
- Shaping Metal By Deep-Drawing, Or The Like (AREA)
Abstract
Description
【発明の詳細な説明】 （産業上の利用分野） 本発明は、フレアチューブを製造する方法に関する。[Detailed description of the invention] (Industrial application field) The present invention relates to a method of manufacturing flared tubes.
（従来の技術）
従来、フレアチューブの製造は、一般に液圧バルジ加工
によっていた。しかしながら、この液圧バルジ加工によ
れば、素管を液密に保持するための高精度な成形型を必
要とするばかりか、大型の油圧ユニットが必要で、設備
コストが高くつくいう問題があった。(Prior Art) In the past, flare tubes were generally manufactured by hydraulic bulging. However, this hydraulic bulging process not only requires a high-precision mold to hold the raw pipe fluid-tight, but also requires a large hydraulic unit, which raises the problem of high equipment costs. Ta.
ところで、最近、鋼管を局部的に円周方向に加熱した後
、両管端から圧縮荷重を加えて加熱部分を膨出させるこ
とを、鋼管の軸方向に所定のピッチで鰻り返すことによ
りフレアチューブを製造する技術が開発されている（特
開昭５９−１４４５２９号公報）。この方法によれば、
成形型を必要としないため、設備コストの低減を図るこ
とができると共に、任意の大きさや肉厚の素管を対象と
し得るという製造上の自由度が得られるようになる。By the way, recently, after heating a steel pipe locally in the circumferential direction, a compressive load is applied from both ends of the pipe to cause the heated portion to bulge. A technique for manufacturing tubes has been developed (Japanese Patent Application Laid-Open No. 144529/1983). According to this method,
Since a mold is not required, it is possible to reduce equipment costs, and it is also possible to obtain flexibility in manufacturing by being able to use raw pipes of any size and wall thickness.
（発明が解決しようとする課題）
しかしながら、上記新たなフレアチューブの製造方法に
よれば、先に膨出成形した山（既成形山）に現在の加熱
部分から熱が伝達されるため、成形ピッチを小さくしよ
うとすると、前記熱の影響により既成形出が座屈してし
まい、成形不能に落ち入り易いという問題があった。(Problem to be Solved by the Invention) However, according to the above-mentioned new flare tube manufacturing method, heat is transferred from the currently heated portion to the bulge-formed ridge (pre-formed ridge), so the forming pitch is If an attempt is made to make it smaller, there is a problem in that the already formed extrusion buckles due to the influence of the heat, and tends to become impossible to form.
また局部加熱−山の膨出成形−冷却のサイクルにより一
山を成形していくため、必要な山数だけこのサイクルを
繰り返さなければならず、思うように生産性を上げ得な
いという問題もあった。In addition, since each mountain is formed through a cycle of local heating, swelling of the mountain, and cooling, this cycle must be repeated as many times as necessary, which poses the problem of not being able to increase productivity as desired. Ta.
本発明は、上記従来の問題に鑑みてなされたもので、座
屈を発生することなく高能率にフレアチューブを製造で
きる方法を提供することを目的とする。The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide a method of manufacturing a flare tube with high efficiency without causing buckling.
（課題を解決するための手段）
本発明は、上記目的を達成するため、素管を、適宜離間
して設けた少なくとも一つの高周波コイルに挿入し、一
つの高周波コイルにより局部的に円周方向に加熱しつ一
両管端から圧縮方向の荷重を加えて加熱部分を膨出させ
、加熱終了とは（同時に前記荷重を加えることを停止し
て該加熱部分を冷却液で冷却し、その冷却途中から他の
一つの高周波コイルにより加熱を開始して前記サイクル
を実行させることを、素管の軸方向に所定のピッチで繰
り返すようにしたことを要旨とする。(Means for Solving the Problems) In order to achieve the above-mentioned object, the present invention inserts a blank pipe into at least one high-frequency coil provided at an appropriate distance, and locally uses one high-frequency coil in a circumferential direction. The heating is completed by applying a load in the compressive direction from both ends of the tube to make the heated part expand (at the same time, stop applying the load, cool the heated part with a cooling liquid, and then The gist is that heating is started by another high-frequency coil midway through and the cycle is repeated at a predetermined pitch in the axial direction of the raw pipe.
本発明において、上記他の一つの高周波コイルによる加
熱開始の時期は、先の一つの高周波コイルによる加熱部
分を冷却している途中であれば特に限定するものでない
が、その冷却を開始した直後に設定するのが望ましい。In the present invention, the timing of starting heating by the other high-frequency coil is not particularly limited as long as the part heated by the previous one high-frequency coil is being cooled, but immediately after the cooling starts. It is desirable to set this.
（作 用）
上記構成のフレアチューブの製造方法において、加熱部
分を冷却液で強制的に冷却するようにしたので、既成形
出に対する熱影響を些少に抑えることができ、結果とし
て成形ピッチを小さくしても既成形出の座屈が起こり難
くなる。(Function) In the flare tube manufacturing method with the above configuration, the heated part is forcibly cooled with a cooling liquid, so the thermal influence on the molded molding can be suppressed to a small extent, and as a result, the molding pitch can be reduced. However, buckling of the pre-formed extrusion becomes less likely to occur.
また加熱途中から圧縮荷重を加えるようにしたので、膨
出部分が高周波コイルの内面に漸次接近し、この結果、
経時的に加熱効率が増して素管の塑性変形能が高まるこ
ととなり、加熱終了とほぐ同時に膨出成形を終えても十
分満足する膨出量が得られるようになる。In addition, since a compressive load was applied during heating, the bulging portion gradually approached the inner surface of the high-frequency coil, and as a result,
As heating efficiency increases over time, the plastic deformability of the raw tube increases, and even if the expansion molding is completed at the same time as the heating is completed and the tube is loosened, a sufficient amount of expansion can be obtained.
しかも、一つの高周波コイルによる加熱部分を冷却して
いる途中に他の一つの高周波コイルによる加熱を開始す
るので、素管または加熱コイルを移動させることなく並
行的に複数の山の成形を完了させることができ、短時間
で所望の山数を得ることができるようになる。Moreover, while the heated part by one high-frequency coil is being cooled, heating by another high-frequency coil is started, so forming multiple peaks can be completed in parallel without moving the raw tube or heating coil. This makes it possible to obtain the desired number of peaks in a short time.
（実施例）
以下、本発明の実施例を添付図面にもとづいて説明する
。(Example) Hereinafter, an example of the present invention will be described based on the accompanying drawings.
第１図は、本発明にか〜るフレアチューブの製造方法を
実行する装置構造を示したものである。同図において、
ｌは加工対象である素管、２．３は前記素管１の管端に
係合し該素管１を挾持する一対のラムである。前記一対
のラム２．３ は、前記素管ｌを挾持した状態で一体的
に横移動できる他、一方のラム２が他方のラム３に対し
て相対的に移動できるようになっている。４．５は前記
一対のラム２．３間に適宜間隔を有して配設された二つ
の高周波コイルで、図示を略す支持フレームに支持され
ている。各高周波コイル４，５は、その内側に冷却液の
噴出孔を具備しており、該素管１に対して冷却液６を噴
射することができるようになっている。FIG. 1 shows the structure of an apparatus for carrying out the flare tube manufacturing method according to the present invention. In the same figure,
Reference numeral 1 denotes a raw pipe to be processed, and 2.3 denotes a pair of rams that engage with the ends of the raw pipe 1 and hold the raw pipe 1 between them. The pair of rams 2.3 are capable of horizontally moving together while holding the blank tube l, and one of the rams 2 is also movable relative to the other ram 3. Reference numeral 4.5 denotes two high-frequency coils disposed at an appropriate distance between the pair of rams 2.3, and supported by a support frame (not shown). Each of the high-frequency coils 4 and 5 is provided with a cooling liquid jet hole inside thereof, so that the cooling liquid 6 can be jetted into the raw tube 1.
か−る装置を用いて、いま一対のラム２．３間に素管ｌ
をセー７トし、先ず一方の高周波コイル４に所定の高周
波電流を供給して素管ｌの加熱を開始し、この加熱開始
かられずか時間経過後、ラム２を移動させて素管１に軸
方向の圧縮荷重を加える。この加熱および圧縮荷重の付
与により、素管１の加熱部分の塑性変形源が増すと共に
この部分に歪が集中し、該加熱部分は徐々に膨出変形す
る。その後、所定時間経過時点で、高周波コイル４に対
する高周波電流の供給を停止し、これと同時にラム２の
移動を停止し、その直後に高周波コイル４の噴出孔から
冷却液６を噴射して前記１膨出部を冷却する。これによ
って前記加熱部分には所定形状の一つの山７が成形され
るようになる。Using such a device, a blank pipe 1 is now inserted between a pair of rams 2.3.
First, a predetermined high-frequency current is supplied to one of the high-frequency coils 4 to start heating the raw tube 1, and after a while from the start of heating, the ram 2 is moved to heat the raw tube 1. Apply axial compressive load. Due to this heating and application of compressive load, the source of plastic deformation in the heated portion of the raw tube 1 increases, strain concentrates on this portion, and the heated portion gradually bulges and deforms. Thereafter, when a predetermined period of time has elapsed, the supply of high-frequency current to the high-frequency coil 4 is stopped, and at the same time, the movement of the ram 2 is stopped, and immediately after that, the cooling liquid 6 is injected from the jet hole of the high-frequency coil 4 to Cool the bulge. As a result, a peak 7 having a predetermined shape is formed in the heated portion.
しかして上記高周波コイル４の噴出孔から冷却液６を噴
射した直後に、他方の高周波コイル５に所定の高周波電
流を供給して素管ｌの加熱を開始し、その後上記と同様
のサイクルで素管１に圧縮荷重を付与しさらに冷却液６
を噴射する。これによって前記高周波コイル５による加
熱部分には他の山８が成形される。つまり、素管ｌを一
度セットした状態で二山７，８ が成形される。Immediately after injecting the coolant 6 from the jet hole of the high-frequency coil 4, a predetermined high-frequency current is supplied to the other high-frequency coil 5 to start heating the raw tube l, and then the same cycle as above is repeated. A compressive load is applied to the tube 1, and the cooling liquid 6
Inject. As a result, another peak 8 is formed in the portion heated by the high frequency coil 5. In other words, the two mounds 7 and 8 are formed with the blank tube l set once.
次に、素管ｌを挾持したま〜一対のラム２゜３を図の右
方へ所定のピッチだけ移動させ、上記と同様のサイクル
により２つの高周波コイル４．５に対応する部分に次の
二山を成形し、か−るサイクルを素管ｌの軸方向に所定
のピッチで縁り返し、これによって所望の山数を有する
フレアチューブが得られるようになる。Next, while holding the raw tube l, move the pair of rams 2°3 to the right in the figure by a predetermined pitch, and use the same cycle as above to move the parts corresponding to the two high-frequency coils 4.5 to the next position. Two ridges are formed and the cycle is repeated at a predetermined pitch in the axial direction of the raw tube 1, thereby making it possible to obtain a flared tube having a desired number of ridges.
第２図は、上記実施例における熱および荷重サイクルを
示したものである。同図中、Ｔｌは一方の高周波コイル
４に対応する部分の温度曲線を、Ｔ２は他方の高周波コ
イル５に対応する部分の温度曲線をそれぞれ表わしてお
り、またＰｌは一方の高周波コイル４に対応する部分の
荷重曲線を、Ｐ２は他方の高周波コイル６に対応する部
分の荷重曲線をそれぞれ表している。FIG. 2 shows the heat and load cycles for the above example. In the figure, Tl represents the temperature curve of a portion corresponding to one high-frequency coil 4, T2 represents a temperature curve of a portion corresponding to the other high-frequency coil 5, and Pl corresponds to one high-frequency coil 4. P2 represents the load curve of the portion corresponding to the other high frequency coil 6, and P2 represents the load curve of the portion corresponding to the other high frequency coil 6, respectively.
これより二山の成形が部分的にラップして進行し、この
サイクルが素管の移動に要する時間ｔをおいて順次繰り
返される様子が明らかである。したがって、全山数で見
ると、−山ずつ成形する場合に比し前記移動時間ｔは半
分となり、ラップ時間と合せて１本のフレアチューブ製
造に要する時間は著しく短縮されるようになる。It is clear from this that the forming of the two peaks progresses while partially lapping, and that this cycle is repeated sequentially after the time t required for the movement of the raw pipe. Therefore, in terms of the total number of ridges, the moving time t is halved compared to the case where the ridges are formed one by one, and the time required to manufacture one flare tube, including the lapping time, is significantly shortened.
以下、上記実施例を具体的に説明する。The above embodiment will be explained in detail below.
こ−では、使用素管として、ＪＩＳＳ丁ＫＭ目Ａ。In this case, the raw pipe used is JISS KM A.
外径３４■馬、肉厚１．０ｍ■、長さ１３０ｍｍのもの
を用い、１２山を有するフレアチューブを得るものとし
た・、この場合、一方の高周波コイル４が １山目に対
応した時に他方の高周波コイルが７山目に対応するよう
に、両高周波コイルの間隔を調整しておく、そして素管
１を一対のラム２．３間にセットし、先ず周波数４０Ｋ
Ｈｚ 、 ４０ＫＷの発振機に結ぶ高周波コイル４にて
、電圧４にＶ、電流７．５Ａの出力で１．８秒間加熱し
た。この加熱により膨出成形部の温度は最高８００℃ま
で到達した。また加熱開始直後からラム２を負荷１トン
、速度 １．８ｍｍ／秒の条件で移動せしめ、加熱終了
と同時にラム２の移動を停止し、その直後、高周波コイ
ル４の噴出孔から冷却液６を３０ＪＪ／ｓｉｎの条件で
噴射して１山目を成形した。A tube with an outer diameter of 34 mm, a wall thickness of 1.0 m, and a length of 130 mm was used to obtain a flare tube with 12 ridges.In this case, when one high-frequency coil 4 corresponds to the first ridge. Adjust the spacing between both high-frequency coils so that the other high-frequency coil corresponds to the 7th peak, then set the raw tube 1 between the pair of rams 2.3, and first set the frequency to 40K.
Heating was performed for 1.8 seconds using a high frequency coil 4 connected to a 40 KW oscillator at a voltage of 4 V and a current of 7.5 A. As a result of this heating, the temperature of the bulging molded portion reached a maximum of 800°C. Immediately after the start of heating, the ram 2 was moved under the conditions of a load of 1 ton and a speed of 1.8 mm/sec, and the movement of the ram 2 was stopped at the same time as the heating was completed. The first ridge was formed by spraying at a rate of 30 JJ/sin.
一方、高周波コイル４から冷却液６を噴射した直後に他
方の高周波コイル５により上記同様の条件で加熱を開始
し、さらに上記と同様の条件でラム２の移動、冷却液６
の噴射を行なって７山目を成形した０次に素管ｌを移動
して上記サイクルを繰り返し、一方の高周波コイル４に
対応する部分に２山目を、他方の高周波コイル５に対応
する部分に ８山目をそれぞれ成形し、その後、順次素
管１を移動して上記サイクルを繰り返し、１２山全部の
成形を終えた。このようにして得たフレアチューブは、
従来法（特開昭５９−１４４５２９号公報に示される方
法）で得たフレアチューブに比し、膨出量において損色
なく、一方、成形ピッチにおいて小ピツチとなることが
確認できた。On the other hand, immediately after injecting the coolant 6 from the high-frequency coil 4, heating is started by the other high-frequency coil 5 under the same conditions as above, and furthermore, under the same conditions as above, the ram 2 is moved and the coolant 6 is injected.
The 7th ridge was formed by the injection of Each of the 8th threads was molded, and then the raw tube 1 was moved one after another and the above cycle was repeated, completing the molding of all 12 threads. The flare tube obtained in this way is
Compared to the flare tube obtained by the conventional method (method disclosed in JP-A-59-144529), it was confirmed that there was no discoloration in the amount of bulge, and on the other hand, the molding pitch was smaller.
なお、上記実施例において、冷却液６の噴射機能を有す
る高周波コイル４，５を用いたが、各高周波コイルに冷
却コイルを付設することにより、この冷却コイル通じて
冷却液を噴出するようにしても良い。In the above embodiment, the high-frequency coils 4 and 5 having the function of jetting the coolant 6 were used, but by attaching a cooling coil to each high-frequency coil, the coolant can be spouted through the cooling coil. Also good.
また上記実施例において、ラム２．３を横方向に配し、
素管１を横移動させるようにしたが、ラム２．３を縦方
向に、配し素管ｌを上下方向へ移動させるようにしても
良い。Further, in the above embodiment, the ram 2.3 is arranged laterally,
Although the blank tube 1 is moved horizontally, the ram 2.3 may be arranged vertically and the blank tube 1 may be moved vertically.
さらに上記実施例において、高周波コイル４．５を固定
状態として素管１を移動させるようにしたが、素管１を
固定的にセットして高周波コイル４．５を移動させるよ
うにして良いことはもちろんである。Further, in the above embodiment, the raw tube 1 is moved with the high frequency coil 4.5 fixed, but it is also possible to set the raw tube 1 fixedly and move the high frequency coil 4.5. Of course.
（発明の効果）
以上、詳細に説明したように、本発明にか＼るフレアチ
ューブの製造方法は、素管の加熱部分を冷却液で強制的
に冷却するようにしたので、既成形出に対する熱形！を
些少に抑えることができて、成形ピッチの可及的縮小を
達成できる効果が得られた。(Effects of the Invention) As explained above in detail, the flare tube manufacturing method according to the present invention forcibly cools the heated portion of the raw tube with a cooling liquid, so Hot form! This resulted in the effect of reducing the molding pitch as much as possible.
また加熱途中から圧縮荷重を加えるようにしたので、加
熱糾了とほゞ同時に膨出成形を終えても十分満足する膨
出量が得られ、冷却液による強制冷却の効果と相まって
、−山の成形時間を著しく短縮することが可能になり、
しかも、一つの高周波コイルによる加熱部分を冷却して
いる途中に他の一つの高周波コイルによる加熱を開始す
るので、素管または加熱コイルを移動させることなく並
行的に複数の山の成形を完了させることができ、生産性
の大幅な向上を達成できる効果が得られた。In addition, since a compressive load is applied from the middle of heating, a satisfactory amount of expansion can be obtained even if the expansion molding is completed almost at the same time as heating is complete. It becomes possible to significantly shorten molding time,
Moreover, while the heated part by one high-frequency coil is being cooled, heating by another high-frequency coil is started, so forming multiple peaks can be completed in parallel without moving the raw tube or heating coil. The result was a significant improvement in productivity.
第１図は本発明にか覧るフレアチューブの製造、方法を
実行する装置の模式図、第２図は本発明における熱およ
び荷重のサイクル線図である。
１ ・・・ 素管
２．３・・・ ラム
４．５・・・ 高周波コイル
６ ・・・ 冷却液
特許出願人 トヨタ自動車株式会社FIG. 1 is a schematic diagram of an apparatus for manufacturing a flare tube according to the present invention and carrying out the method, and FIG. 2 is a cycle diagram of heat and load in the present invention. 1... Raw tube 2.3... Ram 4.5... High frequency coil 6... Coolant patent applicant Toyota Motor Corporation
Claims (1)
周波コイルに挿入し、一つの高周波コイルにより局部的
に円周方向に加熱しつゝ両管端から圧縮方向の荷重を加
えて加熱部分を膨出させ、加熱終了とほゞ同時に前記荷
重を加えることを停止して該加熱部分を冷却液で冷却し
、その冷却途中から他の一つの高周波コイルにより加熱
を開始して前記同様のサイクルを実行させることを、素
管の軸方向に所定のピッチで繰り返すことを特徴とする
フレアチューブの製造方法。(1) Insert the raw tube into at least two high-frequency coils installed at an appropriate distance, heat locally by one high-frequency coil in the circumferential direction, and apply a load in the compressive direction from both ends of the tube. The part is swollen, the application of the load is stopped almost at the same time as the heating ends, the heated part is cooled with a cooling liquid, and heating is started by another high-frequency coil in the middle of cooling, and the same process as described above is carried out. A method for manufacturing a flare tube, characterized in that the cycle is repeated at a predetermined pitch in the axial direction of the raw tube.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1562988A JP2504100B2 (en) | 1988-01-26 | 1988-01-26 | Flare tube manufacturing method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1562988A JP2504100B2 (en) | 1988-01-26 | 1988-01-26 | Flare tube manufacturing method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01192425A true JPH01192425A (en) | 1989-08-02 |
| JP2504100B2 JP2504100B2 (en) | 1996-06-05 |
Family
ID=11894007
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1562988A Expired - Lifetime JP2504100B2 (en) | 1988-01-26 | 1988-01-26 | Flare tube manufacturing method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2504100B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5711177A (en) * | 1996-06-27 | 1998-01-27 | Toyota Jidosha Kabushiki Kaisha | Method for corrugating a metallic pipe |
| CN111389986A (en) * | 2020-03-24 | 2020-07-10 | 上海交通大学 | Method for generating high-strength steel corrugated pipe |
-
1988
- 1988-01-26 JP JP1562988A patent/JP2504100B2/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5711177A (en) * | 1996-06-27 | 1998-01-27 | Toyota Jidosha Kabushiki Kaisha | Method for corrugating a metallic pipe |
| CN111389986A (en) * | 2020-03-24 | 2020-07-10 | 上海交通大学 | Method for generating high-strength steel corrugated pipe |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2504100B2 (en) | 1996-06-05 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EXPY | Cancellation because of completion of term |