JP2504100B2 - Flare tube manufacturing method - Google Patents
Flare tube manufacturing methodInfo
- Publication number
- JP2504100B2 JP2504100B2 JP1562988A JP1562988A JP2504100B2 JP 2504100 B2 JP2504100 B2 JP 2504100B2 JP 1562988 A JP1562988 A JP 1562988A JP 1562988 A JP1562988 A JP 1562988A JP 2504100 B2 JP2504100 B2 JP 2504100B2
- Authority
- JP
- Japan
- Prior art keywords
- tube
- heating
- frequency coil
- cooling liquid
- load
- 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
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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。FIELD OF THE INVENTION The present invention relates to a method of manufacturing flare 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は成形型を
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) Conventionally, the production of flare tubes has generally been performed by hydraulic bulging. However, according to this hydraulic bulge processing, there is a problem that not only a molding die is required for high precision for keeping the raw pipe liquid-tight, but also a large hydraulic unit is required, resulting in high equipment cost. It was
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繰り返すことに
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 flaring a steel pipe locally in the circumferential direction, applying a compressive load from both pipe ends to swell the heated portion is repeated at a predetermined pitch in the axial direction of the steel pipe to form a flare tube. A manufacturing technique has been developed (Japanese Patent Laid-Open No. 59-144529). According to this method, since a molding die is not required, it is possible to reduce the equipment cost and also to obtain the degree of freedom in manufacturing that the target can be a raw pipe of any size and 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山が座屈して
しまい、成形不能の落ち入り易いという問題があった。(Problems to be Solved by the Invention) However, according to the new flare tube manufacturing method described above, heat is transferred from the current heating portion to the bulge (the already-molded ridge) that has been previously bulged, so that the molding pitch is increased. If it is attempted to reduce the value, there is a problem in that the already formed peaks buckle due to the influence of the heat, and the molding cannot be performed easily and falls.
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 one mountain is formed by a cycle of local heating-bulge molding-cooling, this cycle must be repeated for the required number of mountains, and there is also the problem that productivity cannot be increased as expected. It was
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 conventional problems,
It is an object of the present invention to provide a method capable 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
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 Problem) In order to achieve the above-mentioned object, the present invention inserts a raw tube into at least one high-frequency coil provided at an appropriate distance,
While locally heating in the circumferential direction by one high-frequency coil, a load in the compression direction is applied from both tube ends to swell the heated portion, and at the same time as the end of heating, the application of the load is stopped and the heating is stopped. The heating portion is cooled with a cooling liquid, and heating is started by another high frequency coil during the cooling and the cycle is executed, which is repeated at a predetermined pitch in the axial direction of the raw pipe. And
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 it is in the process of cooling the heating portion by the previous high frequency coil, but immediately after starting the cooling. It is desirable to set.
（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
形山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山の座屈が起こり
難くなる。(Operation) In the method of manufacturing the flare tube with the above-mentioned configuration, the heating portion is forcibly cooled with the cooling liquid, so that the heat effect on the already formed mountain can be suppressed to a slight extent, and as a result, the molding pitch can be reduced. Even so, buckling of the already formed mountain is unlikely 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るようになる。In addition, since the compressive load was applied during heating,
The bulging part gradually approaches the inner surface of the high-frequency coil, and as a result, the heating efficiency increases with time and the plastic deformability of the base pipe increases, so it is fully satisfactory even if the bulging is finished at the same time as the end of heating. The amount of swelling 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, since the heating by the other high-frequency coil is started while the portion heated by the high-frequency coil is being cooled, the molding of a plurality of peaks can be completed in parallel without moving the raw pipe or the heating coil. Therefore, the desired number of peaks can be obtained 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 is described based on an accompanying drawing.
第１図は、本発明にかゝ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、１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１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線された二つの高周
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 an apparatus structure for carrying out the method for manufacturing a flare tube according to the present invention. In FIG. 1, reference numeral 1 is a raw pipe to be processed, and reference numerals 2 and 3 are a pair of rams that engage the pipe ends of the raw pipe 1 and hold the raw pipe 1. The pair of rams 2 and 3 can integrally move laterally while holding the element pipe 1 therebetween, and one ram 2 can move relative to the other ram 3. Numerals 4 and 5 denote two high-frequency coils wired between the pair of rams 2 and 3 with an appropriate interval, and are supported by a support frame (not shown). Each of the high-frequency coils 4 and 5 is provided with a cooling liquid ejection hole inside thereof so that the cooling liquid 6 can be ejected to the raw pipe 1.
かゝる装置を用いて、いま一対のラム2,3間に素管１
をセットし、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１の加熱を開始し、この加熱開始か
らわずか時間経過後、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能が増すと共にこ
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, the tube 1 is now between the pair of rams 2 and 3.
, First of all, a predetermined high-frequency current is supplied to one of the high-frequency coils 4 to start heating of the tube 1, and after a lapse of a short time from the start of heating, the ram 2 is moved to move the tube 1 in the axial direction. Apply compressive load. By the heating and the application of the compressive load, the plastic deformability of the heated portion of the raw tube 1 is increased and the strain is concentrated on this portion, so that the heated portion is gradually expanded and deformed. After that, when a predetermined time elapses, the supply of the high-frequency current to the high-frequency coil 4 is stopped, the movement of the ram 2 is stopped at the same time, and immediately after that, the cooling liquid 6 is injected from the ejection hole of the high-frequency coil 4 to expand the expansion. Cool the outlet. As a result, one mountain 7 having a predetermined shape is formed on 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１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１を
一度セットした状態で二山7,8が成形される。Immediately after the cooling liquid 6 is ejected from the ejection holes 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 1, and then the same cycle as described above is used. A compressive load is applied to the pipe 1 and the cooling liquid 6 is further sprayed. As a result, another peak 8 is formed in the heating portion by the high frequency coil 5. That is, the double ridges 7 and 8 are molded with the raw tube 1 set once.
次に、素管１を挾持したまゝ一対のラム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、かゝるサイクルを素管１の軸方向に所定の
ピッチで繰り返し、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, move the pair of rams 2 and 3 holding the tube 1 to the right in the figure by a predetermined pitch, and move the next part to the part corresponding to the two high frequency coils 4 and 5 by the same cycle as above. By forming two peaks and repeating such a cycle at a predetermined pitch in the axial direction of the raw tube 1, a flare tube having a desired number of peaks can be obtained.
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、T1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P1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。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、一山ずつ成形す
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。FIG. 2 shows the heat and load cycle in the above embodiment. In the figure, T 1 represents a temperature curve of a portion corresponding to one high-frequency coil 4, T 2 represents a temperature curve of a portion corresponding to the other high-frequency coil 5, and P 1 represents one high-frequency coil. 4 shows the load curve of the portion corresponding to 4, and P 2 shows the load curve of the portion corresponding to the other high frequency coil 6. From this, it is apparent that the forming of the two crests partially overlaps and progresses, and this cycle is sequentially repeated with the time t required for the movement of the tube. Therefore, when viewed in terms of the total number of peaks, the moving time t is halved as compared with the case of molding one peak at a time, and the time required for manufacturing one flare tube is remarkably shortened together with the lap time.
以下、上記実施例を具体的に説明する。 Hereinafter, the above embodiment will be specifically described.
こゝでは、使用素管として、JIS STKM11A,外径34mm,
肉厚1.0mm,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40KHz,40KWの発振機に結ぶ高周波コイル
４にて、電圧4KV,電流7.5Aの出力が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
1.6mm/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30/minの条件で噴射して１山目を成形し
た。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。次に素管１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ッチとなることが確認でき
た。Here, JIS STKM11A, outer diameter 34mm,
A flare tube having 12 peaks was obtained using a wall thickness of 1.0 mm and a length of 130 mm. In this case, the interval between the two high frequency coils is adjusted so that the one high frequency coil 4 corresponds to the first crest and the other high frequency coil corresponds to the seventh crest. Then, the raw tube 1 was set between a pair of rams 2 and 3, and first, a high frequency coil 4 connected to an oscillator having a frequency of 40 KHz and 40 KW heated an output of a voltage of 4 KV and a current of 7.5 A for 1.8 seconds.
Due to this heating, the temperature of the bulging-molded portion reached a maximum of 800 ° C. Immediately after starting heating, load 2 tons of ram 2 at speed
Move it under the condition of 1.6 mm / sec, and ram 2 at the same time as heating is completed.
Immediately after that, the cooling liquid 6 was jetted from the jet holes of the high frequency coil 4 under the condition of 30 / min to form the first crest. On the other hand, immediately after injecting the cooling liquid 6 from the high frequency coil 4, heating is started by the other high frequency coil 5 under the same conditions as described above, and the ram 2 is moved and the cooling liquid 6 is injected under the same conditions as above. The seventh mountain was molded. Next, the base tube 1 is moved and the above cycle is repeated, a second mountain is formed in a portion corresponding to one of the high frequency coils 4, and an eighth mountain is formed in a portion corresponding to the other high frequency coil 5, and then sequentially. The blank tube 1 was moved and the above cycle was repeated, and the molding of all 12 threads was completed. The flare tube thus obtained is
It was confirmed that, compared with the flare tube obtained by the conventional method (the method disclosed in JP-A-59-144529), the bulging amount was not discolored and the molding pitch was small.
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
冷却液を噴射するようにしても良い。Although the high-frequency coils 4 and 5 having the function of injecting the cooling liquid 6 are used in the above-described embodiment, a cooling coil is attached to each high-frequency coil so that the cooling liquid is injected through the cooling coil. Is 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１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 rams 2 and 3 are arranged in the lateral direction,
Although the base pipe 1 is moved laterally, the rams 2 and 3 may be arranged vertically to move the base pipe 1 in the vertical direction.
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-mentioned embodiment, the high frequency coils 4 and 5 are fixed and the element tube 1 is moved. However, the element tube 1 may be fixedly set and the high frequency coils 4 and 5 may be moved. Of course.
（発明の効果） 以上、詳細に説明したように、本発明にかゝるフレア
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、既成形山に対する熱影響
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 described above in detail, in the method for manufacturing a flare tube according to the present invention, the heated portion of the raw tube is forcibly cooled with the cooling liquid, so that it is possible to prevent the formation of a pre-formed mountain. The effect of being able to suppress the thermal influence to a slight extent and achieving the reduction of the molding pitch as much as possible was obtained.
また加熱途中から圧縮荷重を加えるようにしたので、
加熱終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、一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 the compressive load was applied during heating,
Even if the bulging molding is finished almost at the same time as the heating is completed, a sufficiently satisfactory bulging amount can be obtained, and in combination with the effect of the forced cooling by the cooling liquid, it is possible to significantly shorten the molding time of one mountain, and While the part heated by one high-frequency coil is being cooled, the heating by another high-frequency coil is started, so it is possible to complete the formation of multiple peaks in parallel without moving the raw pipe or heating coil. The result is that the productivity can be significantly improved.
第１図は本発明にかゝ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FIG. 1 is a schematic diagram of an apparatus for carrying out the method for manufacturing a flare tube according to the present invention, and FIG. 2 is a cycle diagram of heat and load in the present invention. 1 …… Element tube 2, 3 …… Ram 4,5 …… High frequency coil 6 …… Cooling liquid
Claims (1)
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. A blank tube is inserted into at least two high-frequency coils provided at appropriate intervals, and is locally heated in the circumferential direction by one high-frequency coil, and a load in the compression direction is applied from both tube ends. The heated portion is bulged out, and at the same time as the end of heating, the application of the load is stopped, the heated portion is cooled by the cooling liquid, and heating is started by another high frequency coil during the cooling, A method for manufacturing a flare tube, characterized in that the same 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 JPH01192425A (en) | 1989-08-02 |
| JP2504100B2 true 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) |
Families Citing this family (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
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01192425A (en) | 1989-08-02 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EXPY | Cancellation because of completion of term |