JPS6283610A - Measuring difference in outer surface level of weld of welded pipe - Google Patents

Abstract

PURPOSE:To measure the quantity of a difference in the outer surface level of a weld on-line by a simple instrument by detecting the quantities of displacement in a horizontal direction and of rotation in a circumferential direction and, in accordance with both of the quantities, correcting differences in the detected values of circumferential distances using the equation of an outer surface profile obtained from the group of the detected values of the distances in the circumferential direction. CONSTITUTION:Equations Y=FL(x), Y=FR(x) indicative of the profiles of outer surfaces in a circumferential direction on both sides of a weld are obtained from the group of the values of detected distances by displacing a distance detector D1 or D2 with a suitable step in a horizontal direction orthogonally intersecting the direction of the axis of a pipe P. Then, a coordinate transformation is applied to the equations of X and Y at a given measuring time in accordance with a horizontal displacement quantity dh and a rotational quantity dQ to be changed to Ya=FL(Xa) and Ya=Fa(Xa), respectively. When the X coordinates (l1, L2) of the measuring points S1a and S2a on the outer surface of the pipe in an X-Y coordinate system are transformed to l1a and l2a, respectively, in an Xa-Ya coordinate system, the quantity dWa of the difference in the outer surface level of the weld that is corrected in accordance with the displacement and rotational quantities dh and dQ, respectively, can be obtained by an accompanying expression, where L1a and L2a are the values of detected distances at the measuring points S1a and S2a, respectively.

Description

【発明の詳細な説明】 （産業上の利用分野） 本発萌は溶接管の溶接部段差を測定する方法に関する。[Detailed description of the invention] (Industrial application field) The present invention relates to a method for measuring the level difference in a welded part of a welded pipe.

（従来の技術） ａ装管の溶接部段差、即ち溶接前の素材側端の突き合わ
せ部の目違いによって生ずる溶接部段差は、管の溶接部
品質と大きな関係があり、溶接管製造工程における重要
な管理項目の一つである。(Prior art) The welded part level difference in a-packed pipes, that is, the welded part level difference caused by the misalignment of the butted parts of the material side ends before welding, has a great relationship with the quality of the welded part of the pipe, and is important in the welded pipe manufacturing process. This is one of the important management items.

この溶接部段差を溶接管製造工程中に測定する従来の方
法として、特開昭５７−１３７８０１号公報に記載の方
法がある。この方法は、管の溶接部にスリット光を照射
して得られる光切断プロフィール受像信号から、溶接部
のピード方向両端（溶接部境界）にそれぞれ連続する外
周面の多数点についてＸ−Ｙ座標を求め、この各点のＸ
−Ｙ座標から溶接部両側の外周面の円の方程式（Ｙ　＝
　ＧＬＦ）　ｍＹ　＝−ＧＲ，、Ｘ）　）　ｔ−求め、
両者の差（Ｄ＝ｌ　Ｇｌ、−ＧＲｌ　）から溶接部段差
を求める方法である＠ （発明が解決しようとする問題点） 上記従来の方法で溶接部段差を測定することは勿論可能
であるが、この方法では光学系及び信号処理装置を含め
て装置の構成が複雑で高価なものとな夛、またこの方法
では溶接ビードを切削した後では段差測定ができないの
で、溶接直後からビード切削までの間、すなわちスクイ
ズロールとビード切削機の間の狭隘な場所に光学基金設
置しなけｎばならないという困難性がある。さらに実際
のオンライン測定においては、管外表面の周方向形状は
必ずしも真円とは限らず、管が移送中に横振れや回転を
起こしたときに段差画定値に誤差が生じるという問題点
があった。そこで本発明は、比較的簡単な装置で溶衾部
段差金測定するために、従来鋼板など平坦な板の突き合
わせ溶接時の段差を検出するのに用いらｎているところ
の、画板面までの距離の差から段差金求める方法全応用
することとし、この方法を用いた場合の管の横振れや回
転による段差測定誤差を補正して正しい溶接部段差ｆ：
ｔｉｌｌ定する方法を提供しようとするものである。As a conventional method for measuring this welded part level difference during the welded pipe manufacturing process, there is a method described in Japanese Patent Application Laid-open No. 137801/1983. This method calculates the X-Y coordinates of multiple points on the outer circumferential surface that are continuous at both ends of the weld in the weld direction (weld boundary) from the optical cutting profile received signal obtained by irradiating the weld of the pipe with slit light. Find the X of each point
- Equation of the circle of the outer peripheral surface on both sides of the weld from the Y coordinate (Y =
GLF) mY = -GR,, X) ) t-calculation,
This is a method of determining the weld level difference from the difference between the two (D=l Gl, -GRl) @ (Problem to be solved by the invention) Although it is of course possible to measure the weld level difference using the above conventional method, However, this method requires a complex and expensive equipment configuration, including the optical system and signal processing device.Also, with this method, it is not possible to measure the level difference after cutting the weld bead, so There is a difficulty in that the optical base must be installed in a narrow space between the squeeze roll and the bead cutting machine. Furthermore, in actual online measurements, the circumferential shape of the outer surface of the tube is not necessarily a perfect circle, and there is a problem in that errors occur in the step definition value when the tube oscillates or rotates during transport. Ta. Therefore, in order to measure the height difference in the weld weld using a relatively simple device, the present invention aims to measure the height difference up to the screen surface, which is conventionally used to detect the height difference during butt welding of flat plates such as steel plates. We will apply all methods for determining the step height from the difference in distance, and correct the step measurement errors due to lateral vibration and rotation of the pipe when using this method to obtain the correct weld step step f:
The purpose of this paper is to provide a method for determining till.

（問題点全解決するための手段） 即ち、本発明は、管外面の溶接部境界近傍全指向する距
離検出器？管の移送経路中に配置し、管軸方向に移送さ
れてきた管の外周上の連接部両側の境界近傍までの距離
亡夫々検出し、該両距、・惟検出値の差から溶接部段差
を求める方法であり、この際、その被測定部近傍の外衣
面の周方向形状が必ずしも真円でない管が移送中に横振
れして水平方向に変位した場合、この水平方向変位によ
って前記距離検出値が変化して段差測定直に誤差紫生ず
るので、この誤差を補正するために管の水平方向の変位
量全検出すること、また管が移送中に外周方向に回転し
た場合、この回転によって前記距離検出値が変化して段
差１ｔ１１１定直に誤差を生ずるので、この誤差金補正
するために管の外周方向回転量を検出すること、及び、
被測定物の管軸方向と直交する水平方向に前記距離検出
器全移動させながら前記距離全検出し、得らｎた周方向
距離検出値群の連なりから溶接部両側の周方向外表面の
プロフィールを表す方程式を求め、前記水平方向変位量
と外周方向回転量の検出１ｉｉ！に応じ前記方程式を用
いて前記距離検出値の差を補正するようにしたｍｉに管
の溶接部段差測定方法である。(Means for Solving All Problems) That is, the present invention provides a distance detector that is oriented all around the boundary of the weld on the outer surface of the pipe. It is placed in the transfer path of the pipe and detects the distance to the boundary on both sides of the joint on the outer periphery of the pipe being transferred in the pipe axis direction, and determines the welded part level from the difference between the two distances and the detected values. In this case, if a tube whose circumferential shape on the outer surface near the part to be measured is not necessarily a perfect circle oscillates during transportation and is displaced in the horizontal direction, the distance can be detected based on this horizontal displacement. Since the value changes and an error occurs immediately when measuring the step, in order to correct this error, it is necessary to detect the entire amount of horizontal displacement of the tube.Also, if the tube rotates in the outer circumferential direction during transfer, this rotation will cause the Since the distance detection value changes and causes an error in the straightness of the step 1t111, it is necessary to detect the amount of rotation in the outer circumferential direction of the tube in order to correct this error, and
The distance detector is moved in the horizontal direction orthogonal to the tube axis direction of the object to be measured, and the entire distance is detected, and the profile of the circumferential outer surface on both sides of the weld is determined from a series of circumferential distance detection values obtained. 1ii! This is a method for measuring a step difference in a welded part of a pipe in which the difference in the detected distance value is corrected using the equation.

（実施例と作用） 以下本発明？′心縫溶接管の製造工程におけるａ接部段
差測定に適用した実施例にもとづき詳細に説明する。(Examples and effects) Is this invention the following? 'A detailed explanation will be given based on an example applied to the measurement of the level difference at the a-junction in the manufacturing process of a corrugated welded pipe.

第１図は本発明の実施例における被測定物と検出器の配
置関係を示す正面図であり、図においてＰは被測定物で
ある溶接管（以下単に管という）であシ、図では真円で
なｈことを誇張して全体を楕円で示しである。ＤＩおよ
びＤｚは管Ｐの上方に配置した距離検出器、Ｄ３及びＤ
４は管Ｐの両側方に配置した距離検出器、Ｄ５は管Ｐの
上方に配置した溶接位置検出器である。管Ｐは図示省略
の移送テーブル上にあって移送中心線ＣＬを中心にして
溶接部Ｂが真上になるようにして管軸方向に移送されて
いる。距離検出器Ｄ１及びり、は管Ｐの上方でかつ、移
送中心線ＣＬの両側に適宜の間隔をおいて配置し７、管
Ｐの溶接部Ｂの両側の外周面上の複数の点までの距離を
夫々検出する。但し、第１図では図面の輻輳とさけるた
めに溶接部中心から水平距離にしてｔｉｉ及びｔ２ｊの
点Ｓｘｉ及びＳ！ｊまでの距離り口及びＬ２ｊ　　を検
出する態様を示しＣある。尚、点８１１１　Ｓ２ｊは同
一外周面上の点でありことが計ｉ！１１１１度上望”ま
しいが、実際には彦の長手方向に極端に（例えば数１０
０−ａ以上）離れなければ実用上は同一外周面上の点で
なくても伍し支えない。距離検出器Ｄ３およびＤ４はａ
Ｐの側方でかつ移送中心線ｃＬの両側に適宜の距離ｔ、
及びｔａｃｔｓ＝ｔ−でもよい）全おいて配置し、摩Ｐ
の外周面までの距離Ｌ３及びＬ４全検出する。この距離
検出値Ｌ３とＬ４の差の１／／２が管Ｐの移送中心線Ｃ
Ｌ（／Ｃ対する水平方向変位量となる。即ち、水平方向
変位量ｄｈは次式で求められる。FIG. 1 is a front view showing the arrangement relationship between the object to be measured and the detector in the embodiment of the present invention. The entire area is shown as an ellipse to exaggerate the fact that it is a circle. DI and Dz are distance detectors placed above the pipe P, D3 and D
4 is a distance detector placed on both sides of the pipe P, and D5 is a welding position detector placed above the pipe P. The pipe P is placed on a transport table (not shown) and is transported in the pipe axial direction about the transport center line CL so that the welded part B is directly above. Distance detectors D1 and D1 are arranged above the pipe P and on both sides of the transfer center line CL at appropriate intervals 7, and measure distances up to a plurality of points on the outer circumferential surface on both sides of the welding part B of the pipe P. Detect the distances respectively. However, in FIG. 1, in order to avoid drawing convergence, points Sxi and S! of tii and t2j are expressed as horizontal distances from the center of the weld. C shows a mode of detecting the distance to j and L2j. Note that the points 8111 and S2j are points on the same outer peripheral surface. 1111 degrees is desirable, but in reality it is extremely extreme in the longitudinal direction of Hiko (for example, several tens of degrees).
0-a or more), it is practically acceptable even if the points are not on the same outer peripheral surface. Distance detectors D3 and D4 are a
An appropriate distance t on the side of P and on both sides of the transfer center line cL,
and tacts=t-), and
The distances L3 and L4 to the outer circumferential surface of are all detected. 1/2 of the difference between these distance detection values L3 and L4 is the transfer center line C of the pipe P.
This is the horizontal displacement amount with respect to L(/C. That is, the horizontal displacement amount dh is determined by the following equation.

ｄｈ−（Ｌｓ　−Ｌ４　）／２　　　　　　・・・・・
回（１）溶接立直検出器Ｄ５は管Ｐの溶接部Ｂ近傍を指
向してその上方に配録し、ｔｄ溶接部の移送中心；尿Ｃ
Ｌに対する水平方向の変位量全検出する検出器である。dh-(Ls-L4)/2...
(1) The welding upright detector D5 is arranged above the welded part B of the pipe P, pointing at the vicinity of the welded part B, and the transfer center of the td welded part; the urine C
This is a detector that detects the entire amount of displacement in the horizontal direction with respect to L.

ここで溶接部Ｂの水平方向変位針の検出１１ａには・θ
Ｐ自体の水平方向変位量と管Ｐの外周方向回転にもとづ
く水平方向変位４の両方が３まｎているので、溶接位置
検出器Ｄ５の検出値ｄＨがら前記水平））向変位量ｄｈ
（ｒ差し引いて管Ｐの回転にもとづく溶接部Ｂの移送中
心線ＣＬに対する水平方向変位量を求める。即ち、管の
回転にもとづく水平方向変位量ｄｒは次式で求めらｎる
。Here, the detection 11a of the horizontal displacement needle of the welding part B is ・θ
Since both the horizontal displacement amount of P itself and the horizontal displacement 4 based on the rotation of the pipe P in the outer circumferential direction are equal to 3, the horizontal displacement amount dh from the detected value dH of the welding position detector D5
(By subtracting r, the amount of horizontal displacement of the welded part B with respect to the transfer center line CL based on the rotation of the tube P is determined. In other words, the amount of horizontal displacement dr based on the rotation of the tube is determined by the following equation n.

ｄ、＝ｄＨ−ｄｈ　　　　　　　　　　・・・・・・・
・・（２）尚、本実施例では装置全簡単にするために・
ａＰの回転にもとづく溶接部の水平方向変位ｍ　ａｒ　
’；ｘ検出するのに間接的な検出方法を採ったが、これ
全直接検出するようにしても良いことは言うまでもない
。d,=dH−dh ・・・・・・・・・
...(2) In this example, in order to simplify the entire device,
Horizontal displacement of the weld based on the rotation of aP m ar
'; Although an indirect detection method was used to detect x, it goes without saying that direct detection may also be used.

第２図は溶接部段差を説明するための図である。FIG. 2 is a diagram for explaining the welded portion level difference.

この図では、便宜的に溶接前の管状成形素管ｐｋ、第１
図の管Ｐの代りに示してあり、この素管ｐの突き合わせ
部の口達ｂ（図は誇張しである）か溶接後の溶接部段差
となる。従って、溶接部段差とは図中のＷで示す溶接前
素管両端部の段差金いうのであるが、浴接仮にオンライ
ンにおいてＷの址全直接測定することは出来ないので、
実操業では、突き合わせ部から一定距離１１およびｔ２
離れた点Ｓ１およびＳ２の相互の高さの違い金もって管
理上の段差としている。この点Ｓ１と８２の高さの差は
、管Ｐ上方の基準位置から線点までの距離Ｌ＋　　’ｉ
びＬ２の差？求めることによって得らｎる。In this figure, for convenience, the tubular formed raw pipe pk before welding, the first
It is shown in place of the pipe P in the figure, and the mouth b (the figure is exaggerated) of the abutting part of this raw pipe p is the welded part step after welding. Therefore, the weld step is the step at both ends of the raw tube before welding, as indicated by W in the figure, but since it is not possible to directly measure the entire surface of W in bath welding on-line,
In actual operation, a certain distance 11 and t2 from the butt part are set.
The height difference between the distant points S1 and S2 is used as a management step. The difference in height between points S1 and 82 is the distance L+ 'i from the reference position above the pipe P to the line point.
Difference between L2 and L2? Obtain by asking.

即ち、本実施例では溶接部段差ｄＷは ｄＷ＝Ｌ１−Ｌ２　　　　　　　　　・・・・・・・・
・（３）として求められる。That is, in this embodiment, the welding part step difference dW is dW=L1-L2...
・It is obtained as (3).

ところで実際の製造工程では、前ｍｌ移送中心線ＣＬｉ
管Ｐの中心が通っているという保証はなく、一般には管
Ｐの振動や横移動等により移送中の管Ｐの中心が所定の
移送中心線ＣＬＫ対ｌ−で水平方向に変位１−ている事
が多く、又、・度Ｐの溶接部（づ―管Ｐの真上になく管
Ｐの中心に対し左右に回転している場合が多い。従って
、管Ｐの溶接部近傍の周方向外表面形状が真円でない場
合には、管中心の水平方向の変位や溶接部の周方向の回
転があると第２図で説明した方法で段差全米めた場合に
誤差金主するので、前述した方法により求めた変位ｔａ
ｂ及びｄｒに応じて（３）代金補正する必要がある。By the way, in the actual manufacturing process, the previous ml transfer center line CLi
There is no guarantee that the center of the pipe P passes through, and in general, due to vibration or lateral movement of the pipe P, the center of the pipe P being transferred is displaced 1- in the horizontal direction by a predetermined transfer center line CLK versus l-. In many cases, the welded part of degree P (Z) is not directly above the pipe P but rotates left and right with respect to the center of the pipe P. Therefore, the welded part of the pipe P near the welded part in the circumferential direction If the surface shape is not a perfect circle, there will be a horizontal displacement of the center of the tube or rotation of the welded part in the circumferential direction, which will lead to errors when the step is completed using the method explained in Figure 2. Displacement ta obtained by the method
(3) It is necessary to correct the price depending on b and dr.

この補正法金第３図及び第４図により説明する。This correction method will be explained with reference to FIGS. 3 and 4.

第３図は管Ｐの溶接部近傍の絢”方向外表面のノロフィ
ール全表わす方程式全米める方法全説明するための図で
あり、図においてＬｌｌ　＋Ｉｊ１２　ｊｌＪ１３＋Ｌ
　１４　ｒ　Ｉｊ　１５及びＬＺＩ・Ｌ’２２　＊　Ｌ
２３　Ｔ　”２４・Ｌ２５　は夫々距離検出器Ｄ！ある
いはＤｚをＩＰのａ軸方向と直交する水平方向に適宜の
ステラ！で移動させたとき（移動機構は図示してない）
に得られる距離検出値群（説明の庚宜上副接部の左右人
々の計測点の数音５個に止めた）である。この２つの距
離検出ｆｉｔ詳Ｌｌｌ”Ｌｉ５及びＬ　２１−Ｌ　２５
に夫々例えば最小自乗法全適用して溶接部間Ｂ１１１の
周方向外表面の！ロフィール全表す方程式Ｙ　＝　ＦＬ
ｊＸンｙＹ＝ＦａｔＸ）と求める。尚、これ等距離検出
全順次行めるに・わたり、距離検出器Ｄ１とＤｚ　’ｆ
ｒ：同時に移動させて溶接部間＄１１１に′ｇ″する距
ｐ進検出ｒ同時に行うようにしても良く、またいづれか
一方の検出４１金移動させ溶接部両側の距離検出全順次
行い曲刃の検出器は１ｍｌ定場せて管の上下振動に対す
る１１ｂ正用として用いることが出来る。又、距離検出
器Ｄ！あるいはＤｚ全水平方向に移動させるに際しその
移動範囲には、第２図に示したｇＰＯ外Ａｍ上の点Ｓ。Fig. 3 is a diagram for explaining the method of calculating the equation that completely expresses the slope of the outer surface of the pipe P in the direction of the weld near the weld.
14 r Ij 15 and LZI・L'22 *L
23 T "24 and L25 are when the respective distance detectors D! or Dz are moved in the horizontal direction orthogonal to the a-axis direction of the IP by an appropriate steller! (the moving mechanism is not shown)
This is a group of distance detection values obtained (for the sake of explanation, I have limited it to 5 measurement points of the people on the left and right of the subjunction). These two distance detection fit details Lll”Li5 and L21-L25
For example, apply the least squares method to each of the circumferential outer surfaces of B111 between welds! Equation Y = FL
jX-yY=FatX). In addition, while all these distance detections can be performed sequentially, the distance detectors D1 and Dz 'f
r: Detection of the distance p to 111 g between the welds by moving at the same time.Alternatively, either one of the detection plates may be moved to detect the distance on both sides of the weld, and the distances on both sides of the weld can be detected in sequence. The detector can be used as a 11b for vertical vibration of the tube by placing it in a fixed position of 1 ml.Also, when moving the distance detector D! or Dz in the entire horizontal direction, the range of movement shown in Figure 2 is as shown in Figure 2. Point S on Am outside gPO.

及びＳ２が含ま扛るようにし、且つ溶接部中心位置金よ
む一定範囲（図中ＸＶｒで示す範囲で溶接ビード部また
はビード切削部とそ゛の直近部に相当）は管外に面とは
異なるグロフィール全しているので計ｌ１Ｊｌｌ　＋−
ｊ’ｊｌ囲から除外ｒ゛ると管Ｐのｄ接部近傍の周方向
外表面プロフィールを表す方程式全精度よく求めるＩｔ
が出来る。即ち、＾１■記距離検出値群Ｌ　ｌ　１””
”’＋５及びＬｚｔ〜２５　　は前記Ｗｒ都の距離検出
器を除外した距離検出１直群である。and S2, and a certain range (the range indicated by I feel everything, so a total of 11Jll +-
j′jl Excluded from the enclosure r゛, the equation expressing the circumferential outer surface profile near the d-junction of the pipe P is determined with full accuracy It
I can do it. That is, the distance detection value group L l 1""
``'+5 and Lzt~25 are the distance detection 1 direct group excluding the distance detector of Wr.

第４図はａ自体の水平方向変位と外周方向回転とによっ
て生ずる見掛けの段差とその補正法金説明するための図
である。いま第・１図に示すよう（／（、Ｘ−Ｙ　座標
において管Ｐの中心が移送中心ｇｅＩ。FIG. 4 is a diagram for explaining the apparent step difference caused by the horizontal displacement and outer circumferential direction rotation of a itself and the amount of correction thereof. As shown in FIG. 1, the center of the tube P is the transfer center geI in the X-Y coordinates.

と一致しているときの管中心ｐｏの座標を原点とし、ｊ
送中の￥ＩＰの中心が移送中心２嵌ＣＬに対してＸ軸方
向にｄＸ／ｆ、け変位し、且つ管Ｐの溶接部位置（第４
図で（づ：省略している）がその中心Ｐｏａ　ｆ軸に１
＋、Ｆ計量りにｄＱ　（ラノアン）だけ回転したとする
と、この変位量ｄＸ々、び回転着ｄＱと前述のようにし
て求められた変’ｉ）’Ｌ　ｆｉ　ｔｉｈ及びｄ、との
関係は次のようになる。The origin is the coordinates of the tube center po when it coincides with j
The center of the IP being transferred is displaced by dX/f in the X-axis direction with respect to the transfer center 2 fitting CL, and the welded part position of the pipe P (the fourth
In the figure, (omitted) is 1 on the center Poa f axis.
+, F The relationship between the amount of displacement dX and the rotating force dQ and the variables 'i)'L fi tih and d obtained as described above is as follows. It will look like this:

ｄＸ＝ｄｈ　　　　　　　　　　川・・・・−（４）ｄ
Ｑ　＃　ｄ　ｒ／Ｒ、・−・−・−・（５）但し、Ｒは
管の公称又は目標外半径もしくは別の方法で計測された
縦軸でちる。縦軸とは溶接部とその相対する下面を挾む
長さの１／２である。dX=dh River...-(4)d
Q # d r/R, (5) where R is the nominal or target outer radius of the tube or the vertical axis measured by another method. The vertical axis is 1/2 of the length between the welded portion and its opposing lower surface.

そこである画定時点における溶接部両側の周方向外表面
プロフィールを表す方程式Ｙ＝ＦＬ（３）及びＹ＝ＦＲ
Ｑｃ）金前記水平方向変位着ｄｈ及び回転漬ｄＱに応じ
て座具変換してＹＩＬ　＝ＦＬ　（ｘａ）及びＹａ＝Ｆ
ａ（Ｘａ）となし、そして管外表面の計測点Ｓｌ＆及び
Ｓ２ａ　のＸ−Ｙ座標軸におけるＸ座標（ｔｔ及びｔ３
　）が、Ｘ１Ｌ−Ｙａ　　座標・紬においては／−１ａ
及びｔｔａ　　になったとすると、管の水平方向変位置
ｄｈ及び外周方向回転量ｄＱに応じて補正さｎた溶接部
段差ｄＷ、は、計測点Ｓｌ＆及び５ＡＩＬ　に対する距
離検出値をＬＩＩＬ及びＬｅ＆とすると、 ｄＷａ　”（Ｌｔａ−Ｌｚａ　）　−（Ｆｔ、（−６ｔ
ａ）　−Ｆａ（ｔｚａ）　）・・・・・・・・・（６） として求めらｎる。Therefore, the equations Y = FL (3) and Y = FR representing the circumferential outer surface profile on both sides of the weld at a certain point in time
Qc) Convert the seat according to the horizontal displacement dh and rotation dQ to yield YIL = FL (xa) and Ya = F
a (Xa), and the X coordinates (tt and t3
) is X1L-Ya coordinates /-1a in Tsumugi
and tta, then the welding part step dW, which is corrected according to the horizontal displacement position dh and the amount of rotation in the outer circumferential direction dQ of the pipe, is as follows: Let the detected distance values for the measurement points Sl& and 5AIL be LIIL and Le& dWa ”(Lta-Lza) −(Ft, (-6t
a) −Fa(tza) )・・・・・・・・・(6)

尚、実際の画定においては、管の外径の変化範囲や市離
検出器自体の測定距離範囲に応じて、距離検出益金上下
方向に可動にしたり、あるいは測定距離範囲（または測
定精度）の異なる検出益金組合せたりすることができる
。距離検出器としては、ンーデやマイクロ波を用いた測
長計、渦流式変位計、静電容置式変位計等の公知の距離
検出器を単独あるいは組合せて使用することができ、又
、溶接位置検出器としては測温弐位置演出益等の公知の
検出器を使用することができる。In actual demarcation, depending on the range of change in the outer diameter of the tube and the measurement distance range of the separation detector itself, the distance detection gain may be moved up and down, or the measurement distance range (or measurement accuracy) may be different. Detected profits can be combined. As the distance detector, known distance detectors such as a distance meter using a meter or microwave, an eddy current displacement meter, a capacitive displacement meter, etc. can be used alone or in combination, and a welding position detector can be used. For this purpose, a known detector such as a thermometer can be used.

（発明の効果） 以上述べたごとく本発明にょｎば、１６棲管の溶接部段
差を溶接管製造工程においてオンライン的に測定するの
に比較的簡単な装置によって測定することができ、また
移送中の管の水平方間変位や回転による周方向変位にも
とづく」１ｊ定、ＡＭｔ補正できて溶接部段差゛と隋度
よく画定できるという実用的に優れた効果がある。(Effects of the Invention) As described above, according to the present invention, the level difference in the welded part of 16 welded pipes can be measured online in the welded pipe manufacturing process using a relatively simple device, and also during transportation. This has a practical effect of being able to correct the 1j constant and AMt based on the horizontal displacement of the pipe and the circumferential displacement due to rotation, and the welded part step can be precisely defined.

【図面の簡単な説明】[Brief explanation of drawings]

第１図は本発明の実施例における検出器の配は関係２示
す正面図、第２図は溶接部段差を説明するための図、第
３図は本発明の実施例における溶接部近傍の周方向外表
面のプロフィールと表す方程式全求める方法を説明する
ための図、第４図は本発明の実施例における溶接部段差
の測定と補正法全説明するための図である。 Ｐ・・・溶接Ａ管、　　　　Ｄ１〜Ｄ４・・・距離検出
器、Ｂ・・・溶接部、　　　　　ｐ・・・素管、Ｄ５・
・・溶接位置検出器。 １・、、、、７　ｍ 代理人　　石　山　輝　雄１：”、、１．、ｊロ一 本　　多　　小　　平１′ じ−」 新　部　興　冶毛゛ ＼−−：ノ 第１図 第２図 ≧ レーＣＬ Ｄｒ、０２−距組検出葛 ｐ−，１蕾 第３図Fig. 1 is a front view showing the arrangement of the detector in the embodiment of the present invention in relationship 2, Fig. 2 is a diagram for explaining the step of the weld, and Fig. 3 is a diagram showing the circumference near the weld in the embodiment of the present invention. FIG. 4 is a diagram for explaining the entire method for determining the profile of the outer surface and the equations representing it. FIG. P...Welded A pipe, D1-D4...Distance detector, B...Welded part, p...Main pipe, D5.
...Welding position detector. 1.、、、、7m Agent Teruo Ishiyama 1: ``、、1. Figure ≧ Ray CL Dr, 02-Length group detection kudzu p-, 1 bud Fig. 3

Claims (1)

【特許請求の範囲】[Claims] 被測定物の外面の溶接部境界近傍を指向して配置した距
離検出器によって外周上の溶接部両側の境界近傍までの
距離を夫々検出し、該両距離検出値の差から溶接部段差
を求めるにあたり、前記距離検出器を被測定物の管軸方
向と直交する水平方向に移動させながら前記距離を検出
し、得られた周方向距離検出値群の連なりから溶接部両
側の周方向外表面のプロフィールを表す方程式を求める
とともに、被測定物の管軸方向と直交する水平方向の変
位量と被測定物の外周方向の回転量を検出し、該変位量
と回転量に応じ前記方程式を用いて前記距離検出値の差
を補正することを特徴とする溶接管の溶接部段差測定方
法。The distances to the boundaries on both sides of the weld on the outer periphery are detected by distance detectors arranged to point near the weld boundary on the outer surface of the object to be measured, and the weld level difference is determined from the difference between the two detected distance values. In this process, the distance is detected while moving the distance detector in a horizontal direction perpendicular to the tube axis direction of the object to be measured, and from the series of obtained circumferential distance detection values, the circumferential outer surface on both sides of the welded part is determined. In addition to finding an equation that represents the profile, the amount of displacement in the horizontal direction orthogonal to the tube axis direction of the object to be measured and the amount of rotation in the outer circumferential direction of the object to be measured are detected, and the equation is used according to the amount of displacement and rotation. A method for measuring a step difference in a welded part of a welded pipe, comprising correcting the difference in the detected distance values.