JPH0724857B2 - Manufacturing method of concentric different diameter double pipe - Google Patents
Manufacturing method of concentric different diameter double pipeInfo
- Publication number
- JPH0724857B2 JPH0724857B2 JP61052650A JP5265086A JPH0724857B2 JP H0724857 B2 JPH0724857 B2 JP H0724857B2 JP 61052650 A JP61052650 A JP 61052650A JP 5265086 A JP5265086 A JP 5265086A JP H0724857 B2 JPH0724857 B2 JP H0724857B2
- Authority
- JP
- Japan
- Prior art keywords
- pipe
- tube
- outer tube
- diameter
- manufacturing
- 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 - Fee Related
Links
Description
【発明の詳細な説明】 産業上の利用分野 本発明は、スピニング加工法によって、テーパー管や段
付管のように直径が長手方向の部分によって異る二重管
（本明細書では「同芯異径二重管」という）を製造する
方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double pipe (in this specification, "concentric" in the present specification, by a spinning method, such as a tapered pipe or a stepped pipe, the diameter of which varies depending on the longitudinal portion. It is referred to as "different diameter double tube").
従来の技術 従来、外管と内管とから成る二重管の製造方法には、溶
接による方法とスエジング加工法による方法とがある。2. Description of the Related Art Conventionally, as a method for manufacturing a double pipe composed of an outer pipe and an inner pipe, there are a welding method and a swaging method.
溶接による方法は、第11図に示すように、長手方向に開
かれた大径管を外管１として、その内側に小径管を内管
２として挿入し、この内管２を巻くような形で、外管１
の開放縁を溶接して二重管とするものである。As shown in FIG. 11, the welding method is such that a large-diameter pipe opened in the longitudinal direction is used as an outer pipe 1, and a small-diameter pipe is inserted as an inner pipe 2 inside the outer pipe 1, and the inner pipe 2 is wound. And the outer tube 1
The open edge of is welded to form a double pipe.
スエジング加工法による方法は、第12図に示すように、
外管１内に内管２と成形型（心型）３を挿入し、成形型
３に従って外管１に対しスエジング加工を行なって、内
管２と共に所定形状に成形するものである。The swaging method is, as shown in FIG. 12,
The inner pipe 2 and the molding die (core die) 3 are inserted into the outer pipe 1, and the outer pipe 1 is swaged according to the molding die 3 to be molded into a predetermined shape together with the inner pipe 2.
発明が解決しようとする問題点 前記、従来技術である溶接法による場合、製品の二重管
は、内管と外管との間にすきまが生じるため、補強手段
として不十分なものとなる。このすきまは、わずかであ
っても二重管の強度は不十分である。Problems to be Solved by the Invention In the case of the above-mentioned conventional welding method, the double pipe of the product is insufficient as a reinforcing means because a gap is generated between the inner pipe and the outer pipe. Even if this clearance is small, the strength of the double pipe is insufficient.
一方、スエジング加工法による場合、二重管の縮径され
た部分は厚肉となって材料の歩留を悪くする。これに対
し、あらかじめ偏肉加工してからスエジングすればよい
が、偏肉加工のコストは高い。またこの方法では、加工
時間が長くなる。更に、成形型を必要とするため、加工
長さに限度がある上、成形型が加工後、管から抜け出せ
ないような同芯異径の複雑な形状に成形する管に対し
て、この方法は適用できない。On the other hand, in the case of the swaging method, the reduced diameter portion of the double pipe becomes thick and the yield of the material deteriorates. On the other hand, it is sufficient to perform uneven thickness processing in advance and then perform swaging, but the uneven thickness processing cost is high. In addition, this method increases the processing time. Furthermore, since a molding die is required, the processing length is limited, and this method is suitable for pipes that are formed into complex shapes with different concentric diameters that prevent the molding die from coming out of the pipe after processing. Not applicable.
そこで、本発明の目的は、従来の技術における上記問題
点を解消し得る同芯異径二重管の製造方法を提供するこ
とである。Then, the objective of this invention is providing the manufacturing method of the concentric different diameter double pipe which can eliminate the said problem in a prior art.
問題点を解決するための手段 本発明による同芯異径二重管の製造方法は、内部に内管
を挿入した中空円筒外管を水平に両端で支持し、該外管
の軸方向に引張力又は圧縮力を加えながら該外管を回転
させ、内管を外管内面に圧接状態に保つとともに、成形
ロールを該外管に押付けながら外管の軸方向に移動させ
て、該外管を前記内管と一体的に所要形状に成形するこ
とを特徴としている。Means for Solving the Problems A method of manufacturing a concentric-diameter double-walled pipe according to the present invention is to support a hollow cylindrical outer pipe having an inner pipe inserted therein horizontally at both ends and to pull the outer pipe in an axial direction. The outer pipe is rotated while applying a force or a compressive force to keep the inner pipe in pressure contact with the inner surface of the outer pipe, and the molding roll is moved in the axial direction of the outer pipe while pressing the outer pipe to move the outer pipe. It is characterized in that it is formed into a required shape integrally with the inner pipe.
この発明の方法で用いる装置を図面を参照して具体的に
説明すると、第１図は上記装置の概要を示す斜視図、第
２図はその縦断面図である。The apparatus used in the method of the present invention will be specifically described with reference to the drawings. FIG. 1 is a perspective view showing the outline of the apparatus, and FIG. 2 is a longitudinal sectional view thereof.
１は中空円筒外管であり、内部に内管２が挿入されてい
る。４は成形ロールであって、外管１に対し接離自在に
かつ外管１の長手方向に移動自在に備えられている。５
は中間支持体で外管１を中間で支えている。Reference numeral 1 is a hollow cylindrical outer tube, and an inner tube 2 is inserted therein. A forming roll 4 is provided so as to be movable in and out of contact with the outer tube 1 and movable in the longitudinal direction of the outer tube 1. 5
Is an intermediate support that supports the outer tube 1 in the middle.
この装置によってスピニング加工するには、外管１の両
端にマンドレル６を挿入し、左端外側から駆動側チャッ
ク７で押え、右端外側から応力付加側チャック８で押え
る。外管１を回転させながら加工しようとする部分に成
形ロール４を押しつける。応力付加側チャック８には油
圧装置（油圧シリンダー）９のピストンロッド10が取付
けられており、この油圧装置９によって、応力付加側チ
ャック８に引張力あるいは圧縮力を加えることができ
る。To perform the spinning process with this apparatus, the mandrels 6 are inserted into both ends of the outer tube 1, and the driving side chuck 7 holds the mandrel 6 from the outside of the left end and the stress applying side chuck 8 holds from the outside of the right end. While the outer tube 1 is being rotated, the forming roll 4 is pressed against the portion to be processed. A piston rod 10 of a hydraulic device (hydraulic cylinder) 9 is attached to the stress applying chuck 8, and a tensile force or a compressive force can be applied to the stress applying chuck 8 by the hydraulic device 9.
この装置によって、テーパ状や段付状の同芯異径二重管
に製造する例を具体的に説明すると、第３図に示すとお
り、成形ロール４を最小径に絞り込む位置に当て、駆動
用チャック７によって外管１を回転させながら成形ロー
ル４を押し下げて所定の外径になるように絞る。外管１
を回転させた場合、外管１の内部に挿入された内管２は
回転の初期においては、自重により外管１の下面に接し
て外管１の回転方向と同方向に自転するが、外管１の回
転数が増すと、自重以上の遠心力が発生して外管１の内
面に沿って動く（自転しつつ外管１の内周面を公転す
る）ようになり、すなわち遠心力によって外管１の内面
に圧接状態に保たれるため、内管２を固定しなくとも外
管１側からの絞り込みに対して長手方向に動くことな
く、外管１と同時に絞り込まれる。更にこの加工中、第
１図および第２図に示した油圧装置９によって、応力付
加側チャック８に矢印の方向に圧力を加えると、外管１
と内管２共に絞り込み部分の肉厚が薄くならない。次に
成形ロール４を右方へ移動させながら、その位置を上げ
て、テーパー加工する際には、第４図の矢印に示すよう
に、外管１に引張力を加えると外管と内管は共に肉厚が
厚くならないでテーパ状に成形することができる。な
お、加工中には中間支持体５を可及的に成形ロール４に
接近させて成形ロール４と共に移動させるのが好まし
い。An example of manufacturing a tapered or stepped concentric-diameter double pipe by this device will be specifically described. As shown in FIG. While the outer tube 1 is being rotated by the chuck 7, the forming roll 4 is pushed down and squeezed to have a predetermined outer diameter. Outer tube 1
When the inner tube 2 is rotated inside the outer tube 1, the inner tube 2 inserted into the outer tube 1 contacts the lower surface of the outer tube 1 by its own weight at the initial stage of rotation and rotates in the same direction as the outer tube 1 rotates. When the number of rotations of the tube 1 increases, centrifugal force more than its own weight is generated and the tube 1 moves along the inner surface of the outer tube 1 (revolves the inner peripheral surface of the outer tube 1 while rotating), that is, by the centrifugal force. Since the inner tube 2 is kept in pressure contact with the inner surface of the outer tube 1, the inner tube 2 is squeezed at the same time as the outer tube 1 without moving in the longitudinal direction even when the inner tube 2 is not fixed. Further, during this processing, when pressure is applied to the stress applying side chuck 8 in the direction of the arrow by the hydraulic device 9 shown in FIG. 1 and FIG.
The inner wall 2 and the inner pipe 2 do not become thinner in the narrowed portion. Next, while moving the forming roll 4 to the right and raising its position to perform taper processing, when a tensile force is applied to the outer pipe 1 as shown by the arrow in FIG. Both can be formed in a tapered shape without increasing the wall thickness. During the processing, it is preferable that the intermediate support 5 is moved as close to the forming roll 4 as possible and moved together with the forming roll 4.
第５図は、最小径に絞り込んだまま、或る長さだけ同径
にすなわち直管に成形する例であり、第６図は２段階
に、縮径された同径部を形成する例であって、いずれの
場合も外管１に矢印のように引張力が作用するように油
圧装置９を作動させる。FIG. 5 shows an example in which the same diameter is formed for a certain length while narrowing down to the minimum diameter, that is, a straight pipe is formed, and FIG. 6 is an example in which the reduced diameter portion is formed in two stages. In any case, the hydraulic device 9 is operated so that a tensile force acts on the outer tube 1 as shown by the arrow.
前記のように、外管１と内管２共にその肉厚を一定に保
持してスピニング加工できるように、第１図及び第２図
に示した装置は、第７図に示すように、回転継手11を介
して油圧装置（油圧シリンダー）９のピストンロッド10
によって応力が加えられるようになっており、被加工材
である外管１の回転継手11の軸方向変位を変位量センサ
ー12によって検出し、該センサーによって検出される外
管１の伸び量あるいは縮み量に応じて、上記油圧装置９
を制御できるようになっている。As described above, the apparatus shown in FIGS. 1 and 2 is rotated as shown in FIG. 7 so that both the outer tube 1 and the inner tube 2 can be spin-processed while keeping their thickness constant. Piston rod 10 of hydraulic system (hydraulic cylinder) 9 via joint 11
Stress is applied by the displacement sensor 12 to detect the axial displacement of the rotary joint 11 of the outer pipe 1 which is the workpiece, and the amount of expansion or contraction of the outer pipe 1 detected by the sensor. Depending on the amount, the hydraulic device 9
Can be controlled.
制御の具体的方法は、軸方向変位量を電気信号に変え、
この信号を油圧装置の自動制御機構に指示して油圧を変
化させるのであるが、このような制御方法は通常の自動
制御手段としてあらゆる分野で採用されている手段を適
用すればよい。The specific control method is to change the axial displacement into an electrical signal,
This signal is instructed to the automatic control mechanism of the hydraulic device to change the hydraulic pressure. As such a control method, a means adopted in all fields as a normal automatic control means may be applied.
内管の外径は、外管の外径の約1/2まで細くても、本発
明の方法によって成形加工することができる。これは、
スピニング加工そのものが縮径率1/2までは、安定して
成形加工が可能な方法となっているからである。すなわ
ち、内管の外径をD1、外管の外径をD2、加工後の内管の
外径をｄとすれば、d/D2が1/2まで安定して加工可能で
あるから、D1/D2≦1/2まで安定して、この方法に適用可
能である。Even if the outer diameter of the inner tube is reduced to about 1/2 of the outer diameter of the outer tube, the molding can be performed by the method of the present invention. this is,
This is because the spinning process itself is a method that allows stable molding up to a diameter reduction rate of 1/2. That is, if the outer diameter of the inner pipe is D 1 , the outer diameter of the outer pipe is D 2 , and the outer diameter of the inner pipe after processing is d, d / D 2 can be stably machined up to 1/2. , It is stable up to D 1 / D 2 ≦ 1/2 and is applicable to this method.
ところで、第８図のａに示すように、内管２に対して、
外管１の方を長くして加工する場合、内管２の切れ目
（ア）部で段差が付くことがある。この場合には、同図
ｂに示すように、内管２の端部を絞り加工又は切削加工
して先細にしておくか、あるいは内管２の端部円周方向
に適宜の間隔をおいてスリットを入れておくと、この段
差の発生は防止できる。By the way, as shown in FIG.
When the outer pipe 1 is processed to be longer, a step may be formed at the cut (a) part of the inner pipe 2. In this case, as shown in FIG. 2B, the end portion of the inner pipe 2 is drawn or cut to be tapered, or the end portion of the inner pipe 2 is provided with an appropriate interval in the circumferential direction. If a slit is provided, this step difference can be prevented.
また、外管外径に対し、内管がかなり小径の場合でも、
前記するように、内管は自重ないしは遠心力によって外
管内面に対して圧接状態に保たれるから、長手方向に動
くことはない。しかし、第９図に示すように、内管２の
先端部が同心的に外管１にはめ込まれるように、外管１
をあらかじめその部分で縮径加工しておくことが好まし
い。In addition, even if the inner tube is considerably smaller than the outer diameter,
As described above, since the inner tube is kept in pressure contact with the inner surface of the outer tube by its own weight or centrifugal force, it does not move in the longitudinal direction. However, as shown in FIG. 9, the outer tube 1 is so arranged that the tip of the inner tube 2 is concentrically fitted into the outer tube 1.
It is preferable to reduce the diameter at that portion in advance.
更に、心金を使用する従来技術では、適用不可能な特殊
形状の二重管構造に対しても、本発明により成形加工す
ることができる。Further, according to the present invention, it is possible to form a double tube structure having a special shape, which cannot be applied by the conventional technique using the core metal.
このような二重管構造の一例を第10図に示す。これは、
照明ポールにおいて安定器などの電装部品を入れる部分
のものであって、ここは開口部13を付ける必要があり、
この開口のために補強手段として二重構造にしたもので
ある。An example of such a double tube structure is shown in FIG. this is,
It is a part of the lighting pole where electric components such as ballasts are inserted, and it is necessary to attach an opening 13 here.
This opening has a double structure as a reinforcing means.
発明の効果 本発明の方法により得られる効果は、以下に記載すると
おりである。Effects of the Invention The effects obtained by the method of the present invention are as described below.
１）成形型を必要とせずに、内管外管密着性の良好な同
芯異径二重管を所要形状に成形することができる。その
製造コストは安価であり、かつ製品の保全性が優秀であ
る。1) It is possible to mold a concentric-diameter double-walled pipe having a good inner-tube outer-tube adherence into a required shape without using a molding die. Its manufacturing cost is low, and the maintainability of the product is excellent.
２）長尺製品また大径製品でも容易に成形することがで
きる。2) Long-sized products and large-diameter products can be easily molded.
３）複雑形状品（例えば、従来技術の場合に使用する成
形型が抜き取れないような形状）に対しても成形が可能
である。3) It is possible to mold even a complicatedly shaped product (for example, a shape in which the molding die used in the case of the conventional technique cannot be removed).
４）内管を外管に固定しなくても、内管の自重ないしは
加工時の遠心力によって内管が抜け出ないため、付帯設
備（内管の固定装置など）が不要である。4) Even if the inner pipe is not fixed to the outer pipe, the inner pipe does not come out due to the weight of the inner pipe or the centrifugal force at the time of processing, so that auxiliary equipment (fixing device for the inner pipe) is not necessary.
なお、内管は固定しない方が、その縮径した部分の肉厚
変動部分が伸びとして挙動するので、加工上有利であ
る。It should be noted that it is advantageous in terms of processing that the inner pipe is not fixed, because the wall thickness varying portion of the reduced diameter portion behaves as elongation.
第１図は本発明の方法に使用する装置の一例を説明する
ための斜視図、第２図は上記装置の縦断面図、第３図な
いし第６図は本発明の方法によって、具体的に外管及び
内管を一体的にスピニング加工する原理を説明するため
の長手方向断面図、第７図は本発明の方法によって、製
品の肉厚を制御するための装置の一例を説明するための
長手方向断面図、第８図のａは外管の方が長い場合に発
生することがある段差の箇所を説明するための長手方向
断面図、同図ｂは段差を防止するために、その先端を加
工した内管の長手方向断面図、第９図は内管が特に短い
場合に、加工前に外管を縮径した状態を示す長手方向断
面図である。 第10図は本発明の方法が適用される製品の一例を示すも
ので、そのａは正面図、ｂは軸方向断面図、第11図は従
来の技術による二重管の製造例を説明するための斜視
図、第12図は別の従来技術による二重管の同様な斜視図
である。 １……外管、２……内管、３……成形型、４……成形ロ
ール、 ５……中間支持体、６……マンドレル、７……駆動側チ
ャック、 ８……応力付加側チャック、９……油圧装置、 10……ピストンロッド、11……回転軸手、 12……変位量センサー、13……開口部。FIG. 1 is a perspective view for explaining an example of an apparatus used in the method of the present invention, FIG. 2 is a longitudinal sectional view of the apparatus, and FIGS. 3 to 6 are specific examples of the method of the present invention. FIG. 7 is a longitudinal sectional view for explaining the principle of integrally spinning an outer pipe and an inner pipe, and FIG. 7 is a view for explaining an example of an apparatus for controlling the product thickness by the method of the present invention. FIG. 8a is a longitudinal sectional view for explaining the location of a step that may occur when the outer tube is longer, and FIG. 8b is the tip of the same in order to prevent the step. FIG. 9 is a longitudinal cross-sectional view of the inner pipe after being processed, and FIG. 9 is a longitudinal cross-sectional view showing a state in which the outer pipe is reduced in diameter before processing when the inner pipe is particularly short. FIG. 10 shows an example of a product to which the method of the present invention is applied, in which a is a front view, b is an axial sectional view, and FIG. 11 is an example of manufacturing a double pipe by a conventional technique. FIG. 12 is a similar perspective view of another prior art double tube. 1 ... Outer tube, 2 ... Inner tube, 3 ... Mold, 4 ... Molding roll, 5 ... Intermediate support, 6 ... Mandrel, 7 ... Driving side chuck, 8 ... Stress applying side chuck , 9 …… hydraulic system, 10 …… piston rod, 11 …… rotating shaft hand, 12 …… displacement sensor, 13 …… opening.
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 昭59−78715（ＪＰ，Ａ) 特開 昭57−177838（ＪＰ，Ａ) 特開 昭51−94459（ＪＰ，Ａ) ─────────────────────────────────────────────────── ─── Continuation of front page (56) Reference JP-A-59-78715 (JP, A) JP-A-57-177838 (JP, A) JP-A-51-94459 (JP, A)
Claims (1)
（１）を水平に両端で支持し、該外管（１）の軸方向に
引張力又は圧縮力を加えながら該外管（１）を回転さ
せ、内管（２）を外管（１）内面に圧接状態に保つとと
もに、成形ロール（４）を該外管（１）に押付けながら
外管の軸方向に移動させて、該外管（１）を前記内管
（２）と一体的に所要形状に成形することを特徴とする
同芯異径二重管の製造方法。1. A hollow cylindrical outer tube (1) having an inner tube (2) inserted therein is supported horizontally at both ends, and the outer tube (1) is applied with a tensile force or a compressive force in the axial direction. The tube (1) is rotated to keep the inner tube (2) in pressure contact with the inner surface of the outer tube (1), and the molding roll (4) is moved in the axial direction of the outer tube while pressing the outer tube (1). Then, the outer pipe (1) is integrally molded with the inner pipe (2) into a desired shape, and a method for producing a concentric different-diameter double pipe.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61052650A JPH0724857B2 (en) | 1986-03-12 | 1986-03-12 | Manufacturing method of concentric different diameter double pipe |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61052650A JPH0724857B2 (en) | 1986-03-12 | 1986-03-12 | Manufacturing method of concentric different diameter double pipe |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62212016A JPS62212016A (en) | 1987-09-18 |
| JPH0724857B2 true JPH0724857B2 (en) | 1995-03-22 |
Family
ID=12920726
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61052650A Expired - Fee Related JPH0724857B2 (en) | 1986-03-12 | 1986-03-12 | Manufacturing method of concentric different diameter double pipe |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0724857B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0745061B2 (en) * | 1987-10-30 | 1995-05-17 | 川崎重工業株式会社 | Method and device for manufacturing double pipe |
| JPH0741307B2 (en) * | 1987-11-02 | 1995-05-10 | 川崎重工業株式会社 | Method and device for manufacturing double pipe |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5194459A (en) * | 1975-02-18 | 1976-08-19 | FUKUGOKINZOKUZAIRYONO SEIZOHOHO | |
| JPS5926378B2 (en) * | 1981-04-24 | 1984-06-27 | 川崎重工業株式会社 | Double pipe manufacturing equipment |
| JPS5978715A (en) * | 1982-10-29 | 1984-05-07 | Toshio Yoshida | Production of double pipe |
-
1986
- 1986-03-12 JP JP61052650A patent/JPH0724857B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPS62212016A (en) | 1987-09-18 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |