| 摘要 |
PURPOSE:To elevate the magnetic detection accuracy at a weld joint, by applying an external magnetic field to the weld joint in the cooling process thereof to raise the magnetic anisotropy. CONSTITUTION:With a welder 5, the tail of a preceding steel strip 1A is welded on the tip of a following strip 1B. After the welding, as a welding current is cut off, the entry of the weld joint 2 into the cooling process is checked with an electromagnet controller 7 by a welding current cutting signal from a welder controller 6 and an exciting current is allowed to flow to an electromagnet 3 through the controller 7 to cut the exciting current to the electromagnet 3 after a specified time passes. The application of a magnetic field starting during the heating can further raise the magnetic anistropy. Then, a weld information signal through the controller 7, a length detection signal from a rotary type length meter 8, a detection signal of the weld joint 2 from a magnetic detector 9 are used as input signal to compute the number and the position of weld joints 2 per the required length of the steel strips and thus, a management data can be obtained at the output terminal 10a of a unit 10. |
