JPS61279327A - Upset working method for tube - Google Patents
Upset working method for tubeInfo
- Publication number
- JPS61279327A JPS61279327A JP12054285A JP12054285A JPS61279327A JP S61279327 A JPS61279327 A JP S61279327A JP 12054285 A JP12054285 A JP 12054285A JP 12054285 A JP12054285 A JP 12054285A JP S61279327 A JPS61279327 A JP S61279327A
- Authority
- JP
- Japan
- Prior art keywords
- upsetting
- wall thickness
- tube
- tube end
- pipe
- 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.)
- Pending
Links
Landscapes
- Forging (AREA)
Abstract
Description
【発明の詳細な説明】 ［産業上の利用分野］ 本発明は、鋼管等の管のアプセット加工方法に関する。[Detailed description of the invention] [Industrial application field] The present invention relates to a method for upsetting a pipe such as a steel pipe.
［従来の技術］
一般に、油井管等の長尺状管の接続方法として、管端の
外面およびまたは内面に形成されたねじ部に継手等を介
装することにより、管を順次接続する方法が用いられて
いる。上記接続方法が適用される管にあっては、その端
部に形成されるねじ部の強度を確保すべく、その端部に
増肉部を形成する必要がある。[Prior Art] Generally, as a method for connecting long pipes such as oil country tubular goods, there is a method in which the pipes are successively connected by inserting a joint or the like into a threaded portion formed on the outer surface and/or inner surface of the pipe end. It is used. In a pipe to which the above connection method is applied, it is necessary to form a thickened portion at the end in order to ensure the strength of the threaded portion formed at the end.
第２図（Ａ）は一般的なアプセット加工方法に゛おける
据込み開始前の状態を示す縦割断面図、第２図（Ｂ）は
同アプセット加工方法における据込み完了時の状態を示
す縦割断面図である。誘導加熱方式等によって高温に局
部加熱された管ｌの端部ＩＡは、その外径より大なる内
径部をなす割ダイス２の据込み領域２Ａに装入されると
ともに、その内径と略同−の外径を有し、割ダイス２内
に常時一定ストロークＳで進入するマンドレルバ−３の
据込み部３Ａによって据込まれ、増肉部４を形成可能と
されている。Fig. 2 (A) is a vertical cross-sectional view showing the state before the start of upsetting in a general upset processing method, and Fig. 2 (B) is a vertical cross-sectional view showing the state after upsetting is completed in the same upsetting method. FIG. The end IA of the tube l, which has been locally heated to a high temperature by an induction heating method or the like, is inserted into the upsetting area 2A of the split die 2, which has an inner diameter larger than its outer diameter, and is approximately the same as the inner diameter. The mandrel bar 3 has an outer diameter of , and is upset by the upsetting part 3A of the mandrel bar 3, which always enters the split die 2 with a constant stroke S, so that the thickened part 4 can be formed.
ここで、アプセット加工を施される管ｌの肉厚士、特に
その端部ＩＡにおいて管ごとに比較的大きく異なるばら
つきがある。Here, there is a relatively large variation in the wall thickness of the tube l to be subjected to upset processing, particularly in the end IA of the tube.
［発明が解決しようとする問題点１
しかしながら、従来のアプセット加工方法においては、
管端部ＩＡの据込領域２Ａへの装入長さ、すなわち割ダ
イス２のシ電ルダ一部２Ｂから据込領域ｚＡ内への管１
の突出長さＬが、連続してアプセット加工されるすべて
の管１に対して同一とされている。[Problem to be solved by the invention 1 However, in the conventional upset processing method,
The charging length of the tube end IA into the swaging area 2A, that is, the length of the tube 1 from the shield part 2B of the split die 2 into the swaging area zA
The protrusion length L is the same for all pipes 1 that are successively upset-processed.
すなわち、従来のアプセット加工方法にあっては、肉厚
の異なるすべての管１が、同一長さＬの部分を、同一ス
トロークＳで据込領域２Ａに進入するマンドレルバ−３
の据込部３Ａによって据込まれる。したがって、肉厚が
標準値より大なる端部ＩＡは、標準増肉体積より大なる
体積分が据込まれることとなり、第３図に示すように、
増肉部４の外面に、余肉が上下の割ダイス２の間にはみ
出したばり４Ａを生ずる。他方、肉厚が標準値より小な
る端部ＩＡは、標準増肉体積より小なる体積分が据込ま
れることとなり、第４図に示すように、増肉部４の内面
にひけ４Ｂを生ずる。ばり４Ａを生じた管ｌは、増肉部
４の外面へのねじ加工のために、ばり４Ａを除去する手
入れ作業が必要となる。また、ひけ４Ｂを生じた管１は
、強度的に不良品として排除され、歩留低下の原因とな
る。That is, in the conventional upset processing method, all the pipes 1 having different wall thicknesses enter the upsetting area 2A with the same stroke S through the same length L of the mandrel bar 3.
Upset by the upsetting section 3A. Therefore, the end portion IA whose wall thickness is larger than the standard value has a volume larger than the standard increased volume, and as shown in FIG. 3,
A burr 4A is formed on the outer surface of the thickened part 4, where the excess thickness protrudes between the upper and lower split dies 2. On the other hand, in the end portion IA whose wall thickness is smaller than the standard value, a volume smaller than the standard thickening area is uprooted, and as shown in FIG. . The pipe 1 in which the burrs 4A are formed requires maintenance work to remove the burrs 4A in order to thread the outer surface of the thickened portion 4. In addition, the tube 1 with the sink mark 4B is rejected as a defective product due to its strength, which causes a decrease in yield.
なお、上記増肉部４のばり４Ａ、ひけ４Ｂの発生を防止
するための方法として、特開昭５９−２１５２２１号公
報に係る技術が提案されている。Incidentally, as a method for preventing the occurrence of the burrs 4A and sink marks 4B in the thickened portion 4, a technique according to Japanese Patent Application Laid-Open No. 59-215221 has been proposed.
この技術は、管端部の肉厚、外径を実測することにより
、管端部の加熱長さを修正した上で、その修正された長
さを加熱の上、厚肉成形するものである。しかしながら
、この技術にあっては、アプセット加工ラインに、複雑
な設備となる肉厚測定装置、外径測定装置を設置するこ
とが必要となる。This technology corrects the heating length of the tube end by actually measuring the wall thickness and outer diameter of the tube end, then heats the corrected length and forms a thick wall. . However, with this technique, it is necessary to install a wall thickness measuring device and an outer diameter measuring device, which are complicated equipment, in the upset processing line.
本発明は、簡素な設備により所定肉厚形状の増肉部を安
定して得ることを目的とする。An object of the present invention is to stably obtain a thickened part with a predetermined thickness using simple equipment.
［問題点を解決するための手段］
本発明は、局部加熱された管端部を割ダイス内の据込領
域に装入し、割ダイス内に一定ストロークで進入するフ
ンドレルバーの据込み部によって管端部を据込み、管端
部に増肉部を形成する管のアプセット加工方法において
、（Ａ）増肉部の標準増肉体積を予め算定するとともに
、（Ｂ）管端部の加熱温度を測定し、（Ｃ）予め定めら
れている管端部の加熱温度と平均肉厚との関係に基づい
て、上記測定温度から管端部の平均肉厚を推定し、（Ｄ
）前記水準増肉体積と上記平均肉厚に基づいて、管端部
の据込み長さを演算し、（Ｅ）管端部の据込み長さ相当
部分を割ダイス内の据込領域に装入して据込むようにし
たものである。[Means for Solving the Problems] The present invention involves loading a locally heated tube end into an upsetting area in a split die, and using the upsetting section of a fundrel bar that enters the split die with a constant stroke to swage the tube. In a pipe upsetting method in which the end is upset and a thickened part is formed at the pipe end, (A) the standard thickened volume of the thickened part is calculated in advance, and (B) the heating temperature of the pipe end is determined. (C) Estimate the average wall thickness of the tube end from the measured temperature based on the predetermined relationship between the heating temperature of the tube end and the average wall thickness, and (D
) Calculate the upsetting length of the tube end based on the level increase volume and the average wall thickness, and (E) Load the portion of the tube end corresponding to the upsetting length into the upsetting area in the split die. It was designed so that it could be inserted and consolidated.
［作 用］
本発明によれば、管端部の加熱温度を測定するという簡
素な設備の使用により、標準増肉体積分の管端部を据込
むこととなり、所定肉厚形状の増肉部を安定して得るこ
とが可能となる。なお、管端部の肉厚のばらつきが５〜
８ｚに達することもあるのに対し、その外径のばらつき
はｌ＄以内であるため、据込み長さの決定にあたり、外
径のばらつきは無視可能である。[Function] According to the present invention, by using simple equipment that measures the heating temperature of the pipe end, the pipe end with the standard thickening volume is upset, and the thickening part with a predetermined wall thickness shape can be made. It becomes possible to obtain it stably. In addition, the variation in wall thickness at the end of the tube is 5~
8z, but the variation in the outer diameter is within l$, so the variation in the outer diameter can be ignored when determining the upsetting length.
第１図は本発明が適用されるアプセット加工装置の一例
を示す模式図である。FIG. 1 is a schematic diagram showing an example of an upset processing apparatus to which the present invention is applied.
本発明の実施において、管体１０は、その管端部を高周
波誘導加熱炉１１において局部加熱される。１２は、加
熱炉１１の入側において管体１０の端面に衝合し、加熱
炉１１による加熱長さを設定するストッパである。In carrying out the present invention, the tube end portion of the tube body 10 is locally heated in a high frequency induction heating furnace 11 . Reference numeral 12 denotes a stopper that abuts against the end surface of the tubular body 10 on the entrance side of the heating furnace 11 and sets the heating length by the heating furnace 11.
加熱炉ｌｌにおいて加熱された管体１０は、アブセッタ
１３に送られる。アプセツタ１３は、上下の割ダイス１
４とマンドレルバ−１５を有している０割ダイス１４は
、管体１０の外径より大なる内径部からなる据込領域１
６を備えている。マンドレルバ−１５は、管体１０の内
径と略同−の外径を有し、常時同一ストロークで据込領
域１６に進入可能とされている。マンドレルバ−１５は
、管体１０の端部を押圧し、増肉部を形成可能とする据
込部１７を備えている。１８は、管体ｌＯの管端挟持部
である。The tubular body 10 heated in the heating furnace 11 is sent to an absetter 13. Upsetter 13 is upper and lower split dice 1
4 and a mandrel bar 15, the 0-percent die 14 has an upsetting area 1 having an inner diameter larger than the outer diameter of the tube body 10.
It is equipped with 6. The mandrel bar 15 has an outer diameter that is substantially the same as the inner diameter of the tubular body 10, and can always enter the upsetting area 16 with the same stroke. The mandrel bar 15 includes an upsetting portion 17 that presses the end of the tubular body 10 to form a thickened portion. 18 is a tube end clamping portion of the tube body IO.
しかして、この実施例においては、加熱炉１１内の出側
よりに温度測定装置１９が設置されている。温度測定装
置１９は、管端部の最終加熱温度を炉内で測定する。温
度測定装！１１９は、管端部の複数位置の温度を測定し
、その平均値を出力可能とする。温度測定装置１９の出
力は、制御器ｚＯに伝達可能とされている。Therefore, in this embodiment, a temperature measuring device 19 is installed closer to the exit side of the heating furnace 11. A temperature measuring device 19 measures the final heating temperature of the tube end within the furnace. Temperature measuring device! 119 measures the temperature at a plurality of positions at the end of the tube and can output the average value thereof. The output of the temperature measuring device 19 can be transmitted to the controller zO.
上記高周波誘導加熱炉１１の周波数、電圧、管体ｌＯの
在炉時間は一定に保たれているので、管端部の最終加熱
温度は、平均肉厚に応じて上下する。したがって、上記
温度を実測することにより、管端部の平均肉厚を推定す
ることが可能となる。すなわち、制御器２０は、予め定
められている管端部の加熱温度と平均肉厚との関係に基
づいて、上記測定温度から管端部の平均肉厚を推定する
。Since the frequency and voltage of the high-frequency induction heating furnace 11 and the in-furnace time of the tube body 10 are kept constant, the final heating temperature of the tube end increases or decreases depending on the average wall thickness. Therefore, by actually measuring the temperature, it is possible to estimate the average wall thickness of the tube end. That is, the controller 20 estimates the average wall thickness of the tube end from the measured temperature based on a predetermined relationship between the heating temperature of the tube end and the average wall thickness.
他方、制御器２０は、管体１ｏの管端部に形成すべき増
肉部の標準増肉体積（割ダイス１４の据込領域１６にお
いて塑性変形を受ける部分の体ｙｉ）を予め算定してい
る。On the other hand, the controller 20 calculates in advance the standard increased volume of the increased thickness portion to be formed at the end of the tube body 1o (the body yi of the portion that undergoes plastic deformation in the upsetting area 16 of the split die 14). There is.
そ゛こで、制御器２０は、上記予め算定しである標準増
肉体積と、上記温度測定装置１９の測定結果から推定さ
れた平均肉厚に基づいて、管端部の据込み長さＬを演算
する。先端からの体積が標準増肉体積となる長さＬは、
管体１ｏの肉厚が標準値である場合には標準長さＬｏと
なり、管体１゜の肉厚が標準値より厚肉である場合には
標準長さＬｏ＞Ｌｌとなり、管体ｌｏの肉厚が標準値よ
り薄肉である場合には標準長さＬｏ＜Ｌ２となる。Therefore, the controller 20 determines the upsetting length L of the pipe end based on the standard increase volume calculated in advance and the average wall thickness estimated from the measurement results of the temperature measuring device 19. calculate. The length L at which the volume from the tip becomes the standard increased volume is:
When the wall thickness of the tube body 1o is the standard value, the standard length is Lo, and when the wall thickness of the tube body 1° is thicker than the standard value, the standard length Lo>Ll, and the length of the tube body lo. When the wall thickness is thinner than the standard value, the standard length Lo<L2.
これにより、制御器２０は、アプセッタ１３の入側に設
置しであるストッパ２１の駆動モータ２２を駆動制御す
る。ストッパ２１は、上記駆動モータ２２の駆動制御に
よって進退して所定位置に設定された状態下で、管体１
ｏの端面に衝合し１割ダイス１４の据込領域１６に対す
る装入長さを前記据込み長さＬ （Ｌｏ 、Ｌｌ 、Ｌ
２）に設定可能とする。Thereby, the controller 20 drives and controls the drive motor 22 of the stopper 21 installed on the inlet side of the upsetter 13. The stopper 21 moves forward and backward under the drive control of the drive motor 22 and is set at a predetermined position.
The charging length of the 10% die 14 into the upsetting area 16 that collides with the end face of the
2) can be set.
すなわち、上記実施例によれば、管端部の加熱温度を測
定するという簡素な設備の使用により、標準増肉体積分
の管端部を据込むこととなり、所定肉厚形状の増肉部を
安定して得ることが可能となる。なお、管端部の肉厚の
ばらつきが５〜８ｚに達することもあるのに対し、その
外径のばらつきはｌｚ以内であるため、上記据込み長さ
しの決定にあたり、外径のばらつきは無視可能である。In other words, according to the above embodiment, by using simple equipment that measures the heating temperature of the tube end, the tube end with the standard thickening volume is upset, and the thickening section with a predetermined wall thickness shape is stabilized. It becomes possible to obtain it by doing so. In addition, while the variation in wall thickness at the end of the pipe can reach 5 to 8z, the variation in the outer diameter is within 1z, so when determining the upsetting length above, the variation in outer diameter is Can be ignored.
なお、上記実施例は、本発明を管体の端部外径を拡径す
るアプセット加工に適用する場合について説明したが、
本発明は、管体の端部内径を縮径するアプセット加工に
も適用可能であり、また、管体の端部外径を拡径しかつ
端部内径を縮径するアプセット加工にも適用可能である
。In addition, in the above embodiment, the present invention is applied to upsetting processing for expanding the outer diameter of the end of a tube body.
The present invention can be applied to upset processing that reduces the inner diameter of the end of a tube, and can also be applied to upset processing that expands the outer diameter of the end of the tube and reduces the inner diameter of the end. It is.
［発明の効果］
以上のように、本発明は１局部加熱された管端部を割ダ
イス内の据込領域に装入し、割ダイス内に一定ストロー
クで進入するコンドレルバーの据込み部によって管端部
を据込み、管端部に増肉部を形成する管のアプセット加
工方法において、（Ａ）増肉部の標準増肉体積を予め算
定するとともに、（Ｂ）管端部の加熱温度を測定し、（
Ｃ）予め定められている管端部の加熱温度と平均肉厚と
の関係に基づいて、上記測定温度から管端部の平均肉厚
を推定し、ＣＤ）前記水準増肉体積と上記平均肉厚に基
づいて、管端部の据込み長さを演算し、（Ｅ）管端部の
据込み長さ相当部分を割ダイス内の据込領域に装入して
据込むようにしたものである。したがって、簡素な設備
により、所定肉厚形状の増肉部を安定して得ることが可
能となる。[Effects of the Invention] As described above, the present invention charges one locally heated pipe end into the upsetting area of a split die, and the pipe is swung by the upsetting part of the condorel bar that enters the split die at a constant stroke. In a pipe upsetting method in which the end is upset and a thickened part is formed at the pipe end, (A) the standard thickened volume of the thickened part is calculated in advance, and (B) the heating temperature of the pipe end is determined. Measure and (
C) Estimate the average wall thickness of the tube end from the measured temperature based on the predetermined relationship between the heating temperature of the tube end and the average wall thickness, and CD) Estimate the average wall thickness of the tube end from the above-mentioned measured temperature; Based on the thickness, the upsetting length of the tube end is calculated, and (E) a portion of the tube end corresponding to the upsetting length is charged into the upsetting area in the split die for upsetting. be. Therefore, it is possible to stably obtain a thickened portion having a predetermined thickness using simple equipment.
第１図は本発明が適用されるアプセット加工装置の一例
を示す模式図、第２図（Ａ）はアプセット加工方法にお
ける据込み開始前の状態を示す縦割断面図、第２図（Ｂ
）は同アプセット加工方法における据込み完了時の状態
を示す縦割断面図。
第３図は従来例における外面ばりの発生状況を示す断面
図、第４図は従来例における内面ひけの発生状況を示す
断面図である。
ｌＯ・・・管体、１１・・・高周波誘導加熱炉、１４・
・・割ダイス、１５・・・マンドレル／＜−，１６・・
・据込領域、１７・・・据込部、１９・・・温度測定装
置、２０・・・制御器、２１・・・ストッパ、２２・・
・駆動モータ。
代理人 弁理士 塩 川 修 治
第 １ 図FIG. 1 is a schematic diagram showing an example of an upsetting apparatus to which the present invention is applied, FIG.
) is a longitudinal cross-sectional view showing the state when upsetting is completed in the same upsetting method. FIG. 3 is a sectional view showing the occurrence of external burrs in the conventional example, and FIG. 4 is a sectional view showing the occurrence of internal sink marks in the conventional example. lO... pipe body, 11... high frequency induction heating furnace, 14...
...Split dice, 15...Mandrel/<-,16...
- Upsetting area, 17... Upsetting section, 19... Temperature measuring device, 20... Controller, 21... Stopper, 22...
・Drive motor. Agent Patent Attorney Osamu Shiokawa Figure 1
Claims (1)
装入し、割ダイス内に一定ストロークで進入するマンド
レルバーの据込み部によって管端部を据込み、管端部に
増肉部を形成する管のアプセット加工方法において、（
Ａ）増肉部の標準増肉体積を予め算定するとともに、（
Ｂ）管端部の加熱温度を測定し、（Ｃ）予め定められて
いる管端部の加熱温度と平均肉厚との関係に基づいて、
上記測定温度から管端部の平均肉厚を推定し、（Ｄ）前
記標準増肉体積と上記平均肉厚に基づいて、管端部の据
込み長さを演算し、（Ｅ）管端部の据込み長さ相当部分
を割ダイス内の据込領域に装入して据込むことを特徴と
する管のアプセット加工方法。(1) The locally heated pipe end is charged into the upsetting area of the split die, and the pipe end is upset by the upsetting part of the mandrel bar that enters the split die at a constant stroke, and the pipe end is In the method for upsetting a pipe that forms a thickened part, (
A) Calculate the standard increased volume of the increased thickness part in advance, and (
B) Measure the heating temperature of the tube end, (C) Based on the predetermined relationship between the heating temperature of the tube end and the average wall thickness,
Estimate the average wall thickness of the tube end from the measured temperature, (D) calculate the upsetting length of the tube end based on the standard increased volume and the average wall thickness, and (E) calculate the upsetting length of the tube end. A pipe upset processing method characterized by charging a portion corresponding to the upsetting length of the pipe into an upsetting area in a split die and upsetting the pipe.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12054285A JPS61279327A (en) | 1985-06-05 | 1985-06-05 | Upset working method for tube |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12054285A JPS61279327A (en) | 1985-06-05 | 1985-06-05 | Upset working method for tube |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS61279327A true JPS61279327A (en) | 1986-12-10 |
Family
ID=14788871
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12054285A Pending JPS61279327A (en) | 1985-06-05 | 1985-06-05 | Upset working method for tube |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61279327A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5956988A (en) * | 1994-10-19 | 1999-09-28 | Audi Ag And Fahrzeugwerk Werdau | Process for heading pipe ends and device for implementing it |
| JP2016073987A (en) * | 2014-10-03 | 2016-05-12 | 新日鐵住金株式会社 | Device and method for manufacturing end-thickened steel pipe |
| CN107249779A (en) * | 2015-02-18 | 2017-10-13 | 新日铁住金株式会社 | End upsetting metal tube and its manufacture method |
-
1985
- 1985-06-05 JP JP12054285A patent/JPS61279327A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5956988A (en) * | 1994-10-19 | 1999-09-28 | Audi Ag And Fahrzeugwerk Werdau | Process for heading pipe ends and device for implementing it |
| JP2016073987A (en) * | 2014-10-03 | 2016-05-12 | 新日鐵住金株式会社 | Device and method for manufacturing end-thickened steel pipe |
| CN107249779A (en) * | 2015-02-18 | 2017-10-13 | 新日铁住金株式会社 | End upsetting metal tube and its manufacture method |
| US10514113B2 (en) | 2015-02-18 | 2019-12-24 | Nippon Steel Corporation | Metal pipe having thickened end portion, and method of manufacturing same |
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