Development of a Camber Measurement System in a Hot Rolling Mill

Camber is one of the most significant defects in a hot rolling mill. This kind of defect may cause the clogging of finishing mill and producing some defects such as strip edge folds, edge cracks, holes, and scrapes etc. The environment conditions in a hot rolling mill are characterized by hot objects, dust and dense steam. Conventional methods for characterizing product parameters fail in these unfavorable measurement conditions. An alternative is optical measurement technique. It is non-contact and can be positioned in a safe location. The design and implementation of an image-based on-line camber measurement system in a hot rolling mill will be described in this paper. As the actual values are almost impossible to obtain, the relationship among measured camber and center-line deviation that measured by width gauge at the same position was studied to validate the results. The system has been currently installed and working in the hot rolling mill for ten months without any problem. By comparison with the measured results, the system has proved to be reasonably accurate.