An On-Line Crook Measurement System of Long Size Rolling Stock

A new principle of on-line crook measurement for long size rolling stock while running is devised, instead of customary off line static measurement. Rolled steel beams and plates aretransferred on roller tables generally accompanied with the motion of traverse and rotation. Therefore, the following three measuring methodes are described. (1) For the case of both traverse and rotation are negligible, and the transfer can be regarded as parallel movement: The camber of the rolling stock can be expressed by processing the sampling measurement data of the rolling stock edge displacement at the fixed point beside the transfer table, with a costant interval of the transfer movement. (2) For the case accompanied with traverse, yet rotation is negligible: Traverse effect is eliminated by sampling measuerment of the stock edge displacement at the fixed two points with a constant interval length beside the transfer table. The camber is calculated by the fundamental camber equation. (3) For the case accompanied with both traverse and rotation: To eliminate the both effects, the method is introduced by sampling measurement of the edge displacement at the fixed three points with a constant length of intervals beside the transfer table. The camber is also calculated by the equation. This principle was applied to on-line crook measurement of steel beam just after rolled. The practical system was developed through the various analysis and experiments. The beam edge dispacement was measured by three detectors of photo-diode arrays. To compensate the vertical crook, ITV deflection detectors were also used. Digital filter processing was introduced to eliminate the short pitch noise of the detecting signal by the mini-computer, which was also used for camber calculation with the measured data. On-line test results of the developed system satisfied fully the aimed accuracy. This on-line crook measurement system may be generally applicable also to various long size stock other than steel beam.