JPS6049060B2 - Processing method for pipes, etc. - Google Patents
Processing method for pipes, etc.Info
- Publication number
- JPS6049060B2 JPS6049060B2 JP55091975A JP9197580A JPS6049060B2 JP S6049060 B2 JPS6049060 B2 JP S6049060B2 JP 55091975 A JP55091975 A JP 55091975A JP 9197580 A JP9197580 A JP 9197580A JP S6049060 B2 JPS6049060 B2 JP S6049060B2
- Authority
- JP
- Japan
- Prior art keywords
- processed
- tube
- pipe
- elastic body
- workpiece
- 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
Links
Landscapes
- Shaping Metal By Deep-Drawing, Or The Like (AREA)
Description
【発明の詳細な説明】
この発明は管等の端部を張出し成形するための加工方法
に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a processing method for stretch-forming the end of a pipe or the like.
従来、管や容器等の一部を張出し成形させるための加工
方法として、管や容器の内部に液圧をｆｉ用させて行う
液圧バルジ法や、管や容器の内部にゴム等の弾性体を入
れて行う工ラストフォーミング法等が知られているが、
これらの方法では被力！工物にあまり大きな変形を与え
ることができなりつた。Conventionally, as a processing method for stretch-molding a part of a pipe or container, there is a hydraulic bulge method in which hydraulic pressure is applied to the inside of the pipe or container, or an elastic material such as rubber is used inside the pipe or container. The last forming method is known, but
With these methods, you are under pressure! It was no longer possible to cause large deformations to the workpiece.
そこで最近では静水圧効果を利用して前高従来の成形方
法よりも大きな変形率が得られる対向液圧成形方法が開
発され、既にこの方法に基いた成形機が実用化されてい
る。この成形方法は、被加工物の内部にコム等の弾性体
を挿入して該弾性体をポンチ等で加圧変形させることに
よつて被加工物を外側へ張出し成形させるという点て従
来の工ラストフォーミング法と類似しているが、被加工
物の外側から静水圧をかけつつ該弾性体をポンチ等で加
圧変形させるので静水圧効果を利用でクき、従つて前記
従来の方法よりも大きな変形率を得られるという利点が
ある。この方法に基いて管の端部を拡管加工する場合、
従来は第１図に示す金型を用いて第２図及び第３図に示
すように加工を行つていた。Recently, a opposed hydraulic forming method has been developed that utilizes the hydrostatic pressure effect to obtain a larger deformation rate than the conventional forming method, and molding machines based on this method have already been put into practical use. This forming method differs from conventional methods in that it inserts an elastic body such as a comb into the workpiece and presses and deforms the elastic body with a punch or the like to stretch the workpiece outward. It is similar to the last forming method, but since hydrostatic pressure is applied from the outside of the workpiece and the elastic body is pressurized and deformed with a punch, etc., the hydrostatic effect can be utilized, and therefore it is more effective than the conventional method. It has the advantage of being able to obtain a large deformation rate. When expanding the end of a tube using this method,
Conventionally, the mold shown in FIG. 1 was used to perform processing as shown in FIGS. 2 and 3.
第１図は５前記の方法を拡管加工に適用する場合の金型
の一例を示したもので、金型本体１は被加工管Ｍの外径
と等しい内径の開口部１ａを有するとともに該開口部１
ａに連通する拡管用キャビティｌｂをその内部に有して
いる。該拡管用キャビティｌｂはフｏ金型本体１の下面
に固定された定盤２によつて閉じられるとともに定盤２
に設けられた液供給通路３に連通し、更に金型本体１に
設けられた液逃がし通路４に連通している。これらの液
供給通路３や液逃力化通路４には流量調整弁や絞り弁等
を設けた配管が接続されるが、第１図には示されて（゛
ない。また、液供給通路３及び液逃がし通路４は、互い
にその役割を兼ねさせてもよい。（なお、Ｓはシールも
しくはパッキンである。）前記の如き構造の金型を用い
て被加工管Ｍの拡管を行う時には、ます、被加工管Ｍを
第２図に示すように金型本体１内に挿入し、次にゴム等
の弾性体５を該被加工管Ｍ内に挿入する。この時、被加
工管Ｍの先端は定盤２の上面に接しており、また弾性体
５の先端面も定盤２の上面に接している。一方、弾性体
５の外径は被加工管Ｍの内径にほぼ等しいので、弾性体
５の外周面も被加工管Ｍの内面に接している。次で、ポ
ンチ６を少し降下させて弾性体５を少量変形させ、これ
によつて金型の開口部１ａの内周面に被加工管Ｍの外周
面を密着させる。次に図示されぬ弁等を開いて液供給通
路３から拡管用キャビティ１ｂ内に高圧液７を導入する
と、該キャビティ１ｂ内の被加工管Ｍの外側には高圧液
７によつて静水圧が作用することになる。この状態で拡
管用キャビティ１ｂ内の圧力を一定に保ちつつ、ポンチ
６を圧下して弾性体５を変形させると第３図に示すよう
に拡管用キャビティ１ｂ内にある被加工管Ｍの部分が拡
管されるが、更に被加工管Ｍの外周面が拡管用キャビテ
ィ１ｂの内周面に密着するまでポンチ６の圧下を；続け
る。前記の如き公知の加工方法に於ては、被加工管の外
側に静水圧をかけながら拡管するので、被加工管に静水
圧効果が働いて被加工管の延性限界を拡大することがで
き、その結果、従来公知のエラ５ストフォーミング法な
どよりも大きな加工率が得られるが、最近の調査による
と、この方法で拡管した製品には第５図に示すように拡
管された部分の外周面に軸方向に波形のしわｍが発生し
やすいことが判明した。FIG. 1 shows an example of a mold in which the above-mentioned method is applied to pipe expansion processing, in which the mold body 1 has an opening 1a with an inner diameter equal to the outer diameter of the pipe M to be processed, and the opening 1a. Part 1
It has inside thereof a cavity lb for pipe expansion which communicates with a. The tube expansion cavity lb is closed by a surface plate 2 fixed to the lower surface of the mold body 1, and the surface plate 2
It communicates with a liquid supply passage 3 provided in the mold body 1, and further communicates with a liquid escape passage 4 provided in the mold body 1. These liquid supply passages 3 and liquid escape passages 4 are connected to piping equipped with flow rate adjustment valves, throttle valves, etc., but these are not shown in FIG. and the liquid escape passage 4 may serve the same role as each other. (S is a seal or packing.) When expanding the pipe M to be processed using a mold having the structure as described above, , the tube M to be processed is inserted into the mold body 1 as shown in FIG. 2, and then an elastic body 5 such as rubber is inserted into the tube M. At this time, the tip of the tube M is in contact with the top surface of the surface plate 2, and the tip surface of the elastic body 5 is also in contact with the top surface of the surface plate 2.On the other hand, since the outer diameter of the elastic body 5 is approximately equal to the inner diameter of the pipe M to be processed, the elastic The outer peripheral surface of the body 5 is also in contact with the inner surface of the tube to be processed M.Next, the punch 6 is lowered a little to deform the elastic body 5 by a small amount, thereby forming a part on the inner peripheral surface of the opening 1a of the mold. The outer peripheral surface of the tube to be processed M is brought into close contact with the outer circumferential surface of the tube to be processed M. Next, when a valve (not shown) is opened and high pressure liquid 7 is introduced into the tube expansion cavity 1b from the liquid supply passage 3, the outside of the tube to be processed M in the cavity 1b is Hydrostatic pressure is applied by the high-pressure liquid 7 to the pipe expansion cavity 1b.In this state, while keeping the pressure inside the tube expansion cavity 1b constant, the punch 6 is depressed to deform the elastic body 5, as shown in Fig. 3. As shown, the portion of the pipe M to be processed inside the cavity 1b for pipe expansion is expanded, but the punch 6 continues to press down until the outer circumferential surface of the pipe M to be processed is brought into close contact with the inner circumferential surface of the cavity 1b for pipe expansion. In the above-mentioned known processing method, since the tube is expanded while applying hydrostatic pressure to the outside of the tube to be processed, the hydrostatic pressure effect acts on the tube to be processed, making it possible to expand the ductility limit of the tube to be processed. As a result, a larger processing rate can be obtained than the conventionally known Elastoforming method, etc., but according to recent research, products expanded by this method have a It was found that wavy wrinkles m tend to occur on the surface in the axial direction.
３そこで、このようなし
わｍの発生する原因について究明を行つたところ、次の
ようなことが判つてきた。すなわち、このような欠陥は
次のような二つの原因によるものであつた。第一の原因
は加工の初期に生ずるものであり、４簡単に言えば、加
工初期に於て被加工管Ｍの先端が定盤２に当接されてい
るために生ずるものである。3. When we investigated the cause of such wrinkles m, we found the following. That is, these defects were due to the following two causes. The first cause occurs at the beginning of machining. 4 Simply put, it occurs because the tip of the tube to be processed M is in contact with the surface plate 2 at the beginning of machining.
これを以下に更に詳細に説明すると次のようになる。
加工初期に於ては前記したようにポンチ６がやや圧下さ
れており、従つて弾性体５の外面は被加工管Ｍの内面に
密着している。This will be explained in more detail below.
At the beginning of machining, the punch 6 is slightly depressed as described above, so the outer surface of the elastic body 5 is in close contact with the inner surface of the tube M to be processed.
次に液体が拡管用キャビティ１ｂ内に満されてポンチ６
が大きく圧７下されると、被加工管Ｍは拡管用キャビテ
ィ１ｂ内でその容積を拡大し、そのため該キャビティ１
ｂ内の液体は液逃がし通路４から徐々に排出されるが、
一部は開口部１ａの壁面に沿つて上昇し、被加工管Ｍの
外周面と該開口部１ａの壁面との間クに侵入して被加工
管Ｍの外周面を潤滑する。その結果、開口部１ａに於て
被加工管Ｍと該開口部１ａとの間の摩擦係数が小さくな
るが、弾性体５の外周面と被加工管Ｍの内周面とは密着
しているのでポンチ６の圧下とともに被加工管Ｍは下方
に向ｊう軸方向力を受けることになる。このため、被加
工管Ｍは下方へ向けて移動しようとするが、この時点で
はまだ被加工管Ｍの先端が定盤２に当接されているため
、被加工管Ｍは圧縮され、その結果、前記の如きしわｍ
が発生することになる。 第二の原因は加工の中期に発
生するもので、これについて第４図を参照して説明する
。 拡管用キャビティ１ｂ内に液体が充填されることの
ない従来の工ラストフォーミング法に於ては、弾性体５
の下端面か定盤２の上面に強く圧接されていて弾性体５
の下端面と定盤２の上面との間には強い摩擦力が生じて
いるので弾性体５の下端部は定盤２によつて拘束されて
いて弾性体５の中央付近に比べ径の拡がり変形が遅れる
が、拡管用キャビティ１ｂ内に高圧液体が存在する図示
の加工方法に於ては、ポンチの圧下が進むにつれて、液
体が弾性体５の下端面と定盤２の上面との間に侵入して
弾性体５の下端面を潤滑してしまうので、弾性体５の下
端部の拘束が弱められ、その結果、弾性体５の下端部は
外側へ広がろうとする。Next, the liquid is filled into the tube expansion cavity 1b and the punch 6
When the pressure 7 is significantly lowered, the pipe M to be processed expands its volume within the tube expansion cavity 1b, and therefore the cavity 1
The liquid in b is gradually discharged from the liquid escape passage 4,
A portion rises along the wall surface of the opening 1a, enters the space between the outer circumferential surface of the tube M to be processed and the wall surface of the opening 1a, and lubricates the outer circumferential surface of the tube M to be processed. As a result, the coefficient of friction between the tube to be processed M and the opening 1a becomes smaller at the opening 1a, but the outer circumferential surface of the elastic body 5 and the inner circumferential surface of the tube to be processed M are in close contact with each other. Therefore, as the punch 6 is pressed down, the pipe M to be processed is subjected to a downward axial force. For this reason, the pipe to be processed M tries to move downward, but at this point, the tip of the pipe to be processed M is still in contact with the surface plate 2, so the pipe to be processed M is compressed, and as a result, , wrinkles as mentioned above
will occur. The second cause occurs during the middle stage of processing, and will be explained with reference to FIG. In the conventional last forming method in which the tube expansion cavity 1b is not filled with liquid, the elastic body 5
The elastic body 5 is strongly pressed against the lower end surface of the surface plate 2 or the upper surface of the surface plate 2.
Since a strong frictional force is generated between the lower end surface and the upper surface of the surface plate 2, the lower end of the elastic body 5 is restrained by the surface plate 2, and the diameter expands compared to the center of the elastic body 5. Although the deformation is delayed, in the illustrated processing method in which high-pressure liquid is present in the tube expansion cavity 1b, as the reduction of the punch progresses, the liquid flows between the lower end surface of the elastic body 5 and the upper surface of the surface plate 2. Since it enters and lubricates the lower end surface of the elastic body 5, the restraint of the lower end of the elastic body 5 is weakened, and as a result, the lower end of the elastic body 5 tends to spread outward.
一方、加工が進むにつれて被加工管Ｍの下端が上昇する
ため、弾性体５の下端部は被加工管Ｍから露出するが、
該下端部に対する拘束力が前記のように小さくなつてい
るので、弾性体５の下端″＄は第４図図示のように被加
工管Ｍの外周部よりＣ も更に外側へ張り出し、その結
果、被加工管Ｍのト端は増々上へ押し上げられ、被加工
管Ｍには更こ軸方向圧縮力が加わることになる。 以上
に説明したように、第１図乃至第４図に示−７た従来の
対向液圧成形方法では被加工管の拡管部位にしわを生じ
やすい欠点があつた。On the other hand, as the processing progresses, the lower end of the tube to be processed M rises, so the lower end of the elastic body 5 is exposed from the tube to be processed M.
Since the restraining force on the lower end has become smaller as described above, the lower end of the elastic body 5 extends further outward than the outer periphery of the pipe M to be processed, as shown in FIG. 4, and as a result, The top end of the pipe M to be processed is pushed upward more and more, and a compressive force in the axial direction is applied to the pipe M to be processed.As explained above, as shown in Figs. The conventional opposed hydraulic forming method has the disadvantage that wrinkles are likely to occur at the expanded portion of the pipe to be processed.
この発明は前記欠点を除くためになされたものてあり、
加工中を通じて被加工管の下端が定盤に接触しないよう
にするとともに、該弾性体の先端部の直径が被加工管の
内径よりも決して大きくならぬように該弾性体の先端部
を成形しておくことにより、被加工管にしわを生じさせ
ずに加工することのできる加工方法を提供するものてあ
る。This invention was made to eliminate the above-mentioned drawbacks,
The tip of the elastic body is shaped so that the lower end of the tube to be processed does not come into contact with the surface plate during processing, and the diameter of the tip of the elastic body is never larger than the inner diameter of the tube to be processed. The present invention provides a processing method that allows processing without causing wrinkles on the pipe to be processed.
以下に第６図を参照して、この発明の実施例について説
明する。第６図はこの発明の方法によつて被加工管Ｍの
管端を拡管加工する状態を示したもので、ポンチ６の圧
下がまだ行われていない時の状態を示している。An embodiment of the present invention will be described below with reference to FIG. FIG. 6 shows the state in which the end of the pipe to be processed M is expanded by the method of the present invention, and shows the state when the punch 6 has not yet been compressed.
この発明の方法では、加工開始前及び加工中を通じて被
加工管Ｍの下端と定盤とが接触せぬような状態を保つと
ともに、定盤２と接する側の先端部５ａの直径が被加工
管Ｍの内径よりも小くなるように成形された弾性体５を
用いることが特徴てある。従つて、加工初期に弾性体５
とともに被加工管Ｍが下向きに働いても被加工管Ｍには
軸方向の圧縮力が作用しない。In the method of the present invention, the lower end of the pipe M to be processed and the surface plate are kept in a state that they do not come into contact with each other before and during the processing, and the diameter of the tip 5a on the side that contacts the surface plate 2 is such that the diameter of the tip 5a on the side that contacts the surface plate 2 is equal to that of the pipe to be processed. A feature is that the elastic body 5 is formed to have a diameter smaller than the inner diameter of M. Therefore, the elastic body 5 is
At the same time, even if the tube to be processed M acts downward, no compressive force in the axial direction acts on the tube to be processed M.
また、加工中期に於て拡管用キャビティ１ｂ内の弾性体
５の横断面積が増大しても、弾性体５の先端部５ａの直
径は被加工管Ｍの内径よりも大きくならず、その結果、
被加工管Ｍの下端が弾性体５の先端部５ａによつて押し
上げられるような事態は発生しない。従つて、この発明
によれば、従来の対向液圧成形方法における欠点が除か
れ、不良品を生ずることなく大きな加工率で管等の端部
を張出し成形することができる。Furthermore, even if the cross-sectional area of the elastic body 5 in the tube expansion cavity 1b increases in the middle stage of processing, the diameter of the tip 5a of the elastic body 5 does not become larger than the inner diameter of the tube M to be processed.
A situation in which the lower end of the tube to be processed M is pushed up by the tip 5a of the elastic body 5 does not occur. Therefore, according to the present invention, the drawbacks of the conventional opposed hydraulic forming method are eliminated, and the end portion of a pipe or the like can be overhang-formed at a high processing rate without producing defective products.
なお、図示実施例では、弾性体５の先端部５ａが截頭円
錐形に成形されている場合のみを示したが、弾性体の先
端部の形状はどのような形状てあつてもよく、先端部直
径が加工中を通じて被加工物の内径よりも小さく保持で
きさえすればよい。In the illustrated embodiment, only the case where the tip 5a of the elastic body 5 is formed into a truncated conical shape is shown, but the tip of the elastic body 5 may have any shape; It is only necessary that the diameter of the part can be kept smaller than the inner diameter of the workpiece throughout the machining.
第１図は公知の対向液圧成形方法に使用する金型の一例
を示す縦断面図、第２図は公知の対向液圧成形方法にけ
る加工開始前の状態を示した図、第３図は前記従来の方
法が理想的に行われた場合の状態を示す図、第４図は前
記従来の方法に於て生じる欠点を説明する図、第５図は
前記従来の方法によつて被加工物に生じる欠陥を示した
図、第６図はこの発明の方法に於ける加工開始前の状態
）を示した図である。
図において、１・・・・・・金型本体、１ａ・・・・・
・開口部、１ｂ・・・・・・拡管用キャビティ、２・・
・・・・定盤、５・・・弾性体、５ａ・・・・・・先端
部、６・・・・・・ポンチ、Ｍ・・・・被加工管。Fig. 1 is a longitudinal sectional view showing an example of a mold used in a known opposed hydraulic forming method, Fig. 2 is a diagram showing a state before processing starts in a known opposed hydraulic forming method, and Fig. 3 is a diagram showing the state when the conventional method is ideally performed, FIG. 4 is a diagram explaining the drawbacks that occur in the conventional method, and FIG. 5 is a diagram showing the state when the conventional method is processed. FIG. 6 is a diagram illustrating defects occurring in an object (before the start of processing in the method of the present invention). In the figure, 1...Mold body, 1a...
・Opening part, 1b...Cavity for pipe expansion, 2...
... Surface plate, 5 ... Elastic body, 5a ... Tip, 6 ... Punch, M ... Tube to be processed.
Claims (1)
び該開口部に連通する大径の拡管用キャビティを有した
金型本体と、該金型本体の下端に固定されて該拡管用キ
ャビティを閉じている定盤と、からなる金型を用いて該
拡管用キャビティ内で該被加工物の外側から静水圧を作
用させつつ該被加工物内の弾性体をポンチで変形させる
ことによつて該被加工物を張出し成形させる加工方法に
於て、該定盤に接する側の先端部の直径が該被加工物の
内径よりも充分小さな弾性体を用いるとともに加工中を
通じて該被加工物の先端が該定盤に接触しない状態を保
持しつつ加工することを特徴とする、管等の加工方法。1. A mold body having a small-diameter opening that is approximately equal to the outside diameter of a workpiece such as a pipe, and a large-diameter tube expansion cavity that communicates with the opening, and a mold body that is fixed to the lower end of the mold body to expand the tube. deforming the elastic body within the workpiece with a punch while applying hydrostatic pressure from the outside of the workpiece within the pipe expansion cavity using a mold consisting of a surface plate that closes a cavity for pipe expansion; In a processing method in which the workpiece is stretch-formed, an elastic body is used whose end portion on the side that contacts the surface plate has a diameter sufficiently smaller than the inner diameter of the workpiece, and the workpiece is stretched during processing. A method for processing pipes, etc., characterized in that processing is performed while maintaining a state in which the tip of the object does not come into contact with the surface plate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP55091975A JPS6049060B2 (en) | 1980-07-02 | 1980-07-02 | Processing method for pipes, etc. |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP55091975A JPS6049060B2 (en) | 1980-07-02 | 1980-07-02 | Processing method for pipes, etc. |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5717329A JPS5717329A (en) | 1982-01-29 |
| JPS6049060B2 true JPS6049060B2 (en) | 1985-10-30 |
Family
ID=14041512
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP55091975A Expired JPS6049060B2 (en) | 1980-07-02 | 1980-07-02 | Processing method for pipes, etc. |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6049060B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6358U (en) * | 1986-06-20 | 1988-01-05 | ||
| JPH05176679A (en) * | 1991-02-20 | 1993-07-20 | Hodaka Kanko Shokuhin:Kk | Complex processed food and its production |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3829246A1 (en) * | 1987-08-28 | 1989-03-16 | Alps Electric Co Ltd | Electrical component |
| JP2780520B2 (en) * | 1991-07-10 | 1998-07-30 | 株式会社日立製作所 | Electric locomotive |
| CN106001291B (en) * | 2016-06-08 | 2018-02-23 | 广东鸿业机械有限公司 | The pattern that rises mould structure and crimping unit |
-
1980
- 1980-07-02 JP JP55091975A patent/JPS6049060B2/en not_active Expired
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6358U (en) * | 1986-06-20 | 1988-01-05 | ||
| JPH05176679A (en) * | 1991-02-20 | 1993-07-20 | Hodaka Kanko Shokuhin:Kk | Complex processed food and its production |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5717329A (en) | 1982-01-29 |
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