Patent ID: 8230709

Claim:
A method of measuring straightness of an elongated rolled-rail, bar, or rod workpiece in a production system where treatment devices including a straightening machine move the workpiece longitudinally in a horizontal travel direction and at a generally constant travel speed along a horizontal longitudinal path and a control computer is connected to the treatment devices, the method comprising the steps of: gripping the workpiece at a pair of longitudinally spaced supports, supporting a longitudinally extending horizontal portion of the workpiece between the supports, and continuously moving the workpiece in the travel direction at the travel speed with a lower surface of the portion substantially unsupported such that the workpiece is downwardly deflected primarily by its weight; at least periodically measuring a vertical spacing between the portion and a straight longitudinal reference line extending in the direction between the supports parallel to the workpiece at the supports; and feeding the vertical-spacing measurement to the computer for use controlling the straightening machine.