PIPELINE MATERIAL AND BENDING RADIUS MEASURING METHOD OF PIPELINE MATERIAL

To provide a measuring method capable of easily measuring bending radius of a curved portion of a pipeline material.SOLUTION: A corrugated pipeline material 1 is provided with a large diameter part 10 and a small diameter part 20 alternately and includes bending radius measuring means. The bending radius measuring means is composed of a first mark 100 of a first large diameter part 10A, a second mark 200 of a second large diameter part 10B and a central gauge part 300 of a third large diameter part 10C. The central gauge part 300 is provided with third marks 310, 320 between the first mark 100 and the second mark 200. The centre of the third marks 310, 320 is a reference point 500 separated from the third mark by a distance Y of the following formula 1. (Formula 1) Y=R(1-cosθ1) and (Formula 2) θ1=(90X)/(Rπ). "R" represents bending radius of a first curved straight line F1( arc AF1) when the pipeline material is bent at bending radius S of the central axis. "X" represents the lengths of the first mark and the second mark of the first curved straight line.SELECTED DRAWING: Figure 1 【課題】管路材の湾曲部位の曲げ半径を簡単に測定できる測定方法を提供する。【解決手段】大径部１０と小径部２０とが交互に設けられ、曲げ半径測定手段を備えた波形の管路材１。曲げ半径測定手段は、第１の大径部１０Ａの第１マーク１００と、第２の大径部１０Ｂの第２マーク２００と、第３の大径部１０Ｃの中央ゲージ部３００とから構成されている。中央ゲージ部３００には、第１マーク１００と第２マーク２００の中心となる第３マーク３１０、３２０が設けられている。第３マーク３１０、３２０の真ん中は、第３マークから下記式１の距離Ｙだけ離れた基準点５００となる。（式１）Ｙ＝Ｒ（１－ｃｏｓθ１）（式２）θ１＝（９０Ｘ）／（Ｒπ）「Ｒ」は中心軸の曲げ半径Ｓで管路材を湾曲させたとき、湾曲した第１直線Ｆ１（円弧ＡＦ１）の曲げ半径を示す。「Ｘ」は湾曲した前記第１直線の第１マークと第２マークの長さを示す。【選択図】図１