Geometric in-line inspection of profiled strips and welding seams

In this paper two in-line measurement systems for the geometric inspection of welded or profiled steel strips are presented. For the first case, the welded strips, the paper presents a light sectioning based measurement system for the in-line inspection of the welding seam. The system measures the vertical and angular misalignment of the welded parts in-line, right after the welding station. Based on the calculated offset of the two welded parts on one hand the welding adjustment can be optimized. On the other hand, quality relevant data is collected. The inspection of the vertical offset is done with an accuracy of ±5μm (±2σ). In addition to the measurement of the vertical and angular offset, the system also inspects the width of the welding seam and the seam's shape and depth, all three with an accuracy of ±15μm (±2σ). The second system presented in the paper is a measurement system for the inspection of the cross section of profiled strips. The system consists of three light sectioning based measurement heads and is mounted right after the profiling plates. Regarding the measurement precision, the shape of the profiled strip can be measured with an accuracy of better than ±10μm (±2σ). The paper for both applications describe the sensor setup, geometric conditions, the used hardware and the calibration and registration approaches.