AUTOMATIC QUALITY-CONTROL OF CONTINUOUSLY CAST SLABS FOR HOT-ROLLING USE

Plant and production range of the Linz Steelworks. Original quality co ntrol based on a production specification file. Requirements placed on the computer-assisted quality assurance system. Development of a new system using computerized specifications and automatic defect forecast ing. Implementation of the system in several steps between 1983 and 19 93. Key features ensuring system reliability include monitoring of mea suring equipment, use of statistical process control, and collection o f feedback data from the rolling mill. Accomplished production and qua lity improvements: 83% of slabs produced require no inspection or trea tment, 72% reduction in scarfing loss, 80% decrease in strip re-inspec tions necessitated by metallurgical defects.