A new automated system installed in the ArcelorMittal Asturias steel plant in Aviles, based on novel image treatment, aims at performing an on-line inspection, with feed-back to the process, verifying the effectiveness of scarfing. It detects remaining defects as well as new ones introduced by this operation, thus allowing a quick and reliable assessment of final surface quality.

EMF in a blast furnace can be used to predict liquid level variations into the hearth. After the strong influence of some process parameters has been minimized, the variation of the EMF at the end of consecutive castings can be used as a criterion of liquid level variations. Currently this criterion is integrated in a mathematical model that sends messages to an on-line advisory tool.

Results of industrial converter operation have been analyzed with several approaches, based on statistics or on the kinetics of the various reactions. Cogent results have also been obtained through the follow up of gas emissions. The kinetics models that have been developed constitute a significant contribution to the implementation of new strategies for converter operation.

Up to now, no model or contactless sensor has been available for on-line control of the effectiveness of the flow of the stirring gas in the ladle in secondary metallurgy. A new method, based on the use of conoscopic holography, has been developed by Arcelor-Aceralia. It measures on line the vibrations in the walls of the ladle and relates them to the argon flow rate. This method is useful for determining the real state of the stirring process, obtaining an accurate index of the process of melt agitation that influences the composition homogeneity and cleanliness.

A new technique for automatic assessment of centre line segregation based on image analysis is presented. This innovative tool can detect both centre line segregation and centre line cracks from digitalized sulphur prints giving an objective result. A data base containing process data from the caster and the new index for segregation measurement have been created. First analyses of this data base by data mining tools have been performed showing very promising results.

The mechanism of slag rim behaviour and flux infiltration in the CC mould is reported based on industrial characterizations and on fluid dynamics modelling of the effect of oscillation and shell velocity.Lubrication is not stable as the slag film happens to be broken down and renewed several times during casting. A mechanism of slag infiltration is put forward and the main factors for oscillation marks formation are pointed out.

A new, advanced and breakthrough technology has been developed for hot slab on-line surface inspection and installed in Aceralia (Spain). This innovative inspection system, integrating novel Conoscopic Holography, CCD cameras, a complex mechanical system and intelligent tools, operates in the real environment of a continuous casting facility, allows on-line hot slab surface inspection of 100 % of the production, detecting cracks -without removing the surface scale- and inclusions (peeling a narrow strip on the surface).

This ECSC Draft Final Report completes the activities carried out by Aceralia (Coordinator; Spain), CSM (Italy) and Universidad de Oviedo (Spain) from July 1.998 to June 2.001 During the development of this project, all the activities, realised according with the work-plan, were aimed to the final target of the project: put in operation an Inspection System that working in real time can perform an on-line inspection of the surface of each slab produced in the Continuous Casting Machine of the LDA Steel-plant of ACERALIA, the platform for the trials. According with the aim of the project, and most precisely with the scheduled activities, it was developed the Functional and Technical Specifications concerning the project, as the basis for further activities, as well as the strategy for laboratory and field trials with the kind of slabs to be treated in this project. Functional and Technical Specifications deal about different topics and objectives; three are these objectives: definitions of cracks, definition of inclusions and definitions of the characteristics of the detection devices to be used. A very important role was played by the Mechanical Structures and Communications Nets. The study of the theoretical classification of the defects leads to the definition of the optical equipment to be used, the hardware and software, and finally to the design of the Mechanical Structure where all the equipment is housed. The Expert System needs a detailed classification of the cracks and inclusions with which it must to deal, as well as the rules to assess them. The Technical and Production Departments has supplied these rules. Thus, the main activities at the beginning of the development of the project were not only to define and to characterise the cracks to be detected and qualify them, but also the definition of the inclusion: single ones size, clusters, steel grades affected, etc. All topics regarding the cracks are described in detail in a specific chapter. The most important aspects to be considered are their position in the slab, orientation and shape. The three dimensions that characterise a crack are not independent, in the sense that the longer is the crack, the greater is its wide and depth. The location of the different classes of cracks is not uniform. It means that there are preferences in the formation of cracks of each class depending of the position in the surface, i.e., there is a relationship between type of crack and its position and orientation. In this line, trials were performed in the steel plant, as well with hot and cold slabs. Hot slabs must be understood as those with a temperature in the surface ranging in the interval [700 , 900] °C and cold slabs when their surface temperature is lower than 100°C. Trials for real inspection are made with slabs covered with the scale formed during the casting process. The main idea was to do these tests in the worst case, and so verify the goodness of the optical devices and algorithms to be used in the detection and evaluation of the different kinds of defects. The most important target in each test was that oriented to analyse the shape of the cracks. These trials were focused in optical topics, leading to a precise definition of the power of the cameras to be used and the most accurate distance to the slab under observation.