Steel rolling technology has achieved such fantastic progress in the 20th century that it might be considered to have come to maturity.Actually, it remains nowadays the object of intense development thataffords further impressive improvements. The progress of rollingtechnology is fostered by a drastic global growth of the number ofrolling equipments on the order of 40% over the last 15 years. Itbenefits from a dedicated R&D effort based upon a large scope ofscientific knowledge. The 9th Steel Rolling Conference illustrates thispotent innovative approach and it offers a unique opportunity forfruitful exchanges between steel producers, equipment suppliersand steel users.

A new SSMR process to produce ultra-fine-grained hot strip is introduced,featuring: closely spaced rolling stands, continuous highspeed rolling with moderately large reductions rolling, rapid interpasscooling and rapid finish rolling cooling. An ultra-fine-grained CMnsteel strip (1μm) is obtained with a 700 MPa yield stress. Aproper choice of the work roll diameter and a careful control of thefriction coefficient should make it possible to keep the rolling forceat a level compatible with the design capacity of a conventional rollingmill.

Strip width necking may be quite significant on cold rolling mills. Tocompensate for this unpredicted phenomenon, hot strips are oftenordered with an over-width with resulting substantial over costs, fortrimming in particular. Based upon numerical simulation supportedby rolling trials, the main factors that effect strip width variation havebeen quantified: edge drop, transverse stress relaxation, thermalcontraction. Potential width actuators to be implemented on industrialcold rolling lines have been identified.

The cooling of working rolls is a critical factor of the hot rolling process,to limit roll surface wear and to control roll thermal deformation.An inverse heat conduction approach and an experimentalmethod for measurement of heat transfer coefficient are presented.Heat transfer in the sprayed area is dependent on a large number offactors, such as surface temperature, roll velocity, local pressure,coolant jets inclination and interference of multiple sprays. The experimentalapproach is the only reliable method to get a precise descriptionof the cooling of industrial working rolls.

Dynamic modeling, as an effective decision support tool, is illustratedby the coupling of two continuous lines. The method stands outas general and easily transferable. Modeling makes it possible toassess the impact of various managerial decisions within a globalindustrial environment. Modeling is a preferred tool to extract knowledgefrom data bases, to formulate and to test new ideas.

In 2000, ACB decided to double the capacity of the thin slab casterand of the hot strip mill with a view to substitute ultra thin hot stripfor conventional cold strip on the market. To cope with the extra tonnage,a new pickling line had to be installed. The main features of thenew pickling lines that makes it possible to process thin gauges atreduced total costs, are presented.

CST has supplied 1.5 million tons of tin plate slabs to the world marketsince 1997 for several final applications, including D&I, DrawCans, Double Reduction, Easy Open End. After CSTs hot strip millwas commissioned in September 2002, the Company has suppliedhot coils for the foreign market tin plate production since March2003. In partnership with its customers, CST defined criteria for slabapplication based on continuous casting quality events and continuouscasting parameters, and their relationship with the qualityresults on the final product.