Increasing demands on cold strip quality place a growing requirement on good flatness. Traditional flatness measurement systems are contact based systems, which can cause scratching of the strip surface, and require extensive maintenance work. The SI-FLAT method developed by Siemens uses a contactless measuring principle. It minimizes the risk of scratches and reduces operating and maintenance costs. The system is less sensitive to tension variations and mechanical misalignments, and provides best resolution at the strip edges because of narrow sensor stacking and integrated strip edge detection. SI-FLAT is proven for steel, stainless steel, non-ferrous material and aluminium.

This article describes an innovating measuring device to continuously assess the powder coverage on the whole surface of the mould in a continuous casting process. The measurement is based on the use of a thermal imager device moved along the mould. With adequate translation and rotation of the camera, it is possible to view up to 72 % of the surface of the mould. A dedicated program for images acquisition and processing displays coloured maps of the mould on which areas with poor powder coverage are clearly highlighted. With this technique, the control of the powder addition in a closed loop way, by using the analysis of the image, is possible.

CST has among its priorities the sustainable development and basedon it the sinter plant unit has a commitment to reduce the atmosphericemissions, by developing actions that assure the continuousimprovement on process and the development of equipment linkedwith environmental control, and also with raw materials consumed inthe process. This paper aims at showing all evolutions on theenvironmental control at the sinter plant, with reference to dust andSO2 emissions, and also the visibility of the plume stack.

Considerable changes of the blast furnace have occurred during the last 250 years including technology changes (dimensions, ancillaries, charging, casting) as well as operating parameters (fuels, ores, blast temperatures, productivity). Such evolutions have led to a better description of the reactor through internal measurements and more and more precise heat and mass balances and to the formulation of the final blast furnace theory in the late fifties. From the 17th to the 20th century, a number of Scientists have brought their contributions to the blast furnace theory up until the final paradigm shift in the fifties. This paper highlights French contributions to this scientific history, in relation with the advances of blast furnace theory in other countries.

EU regulations to be proclaimed will insist on product life cycle, Health-Safety-Environment issues and they will further enforce new ecotaxes. Anticipating these demands would afford Steel a competitive advantage and would further improve its image. The objectives of coated steel products, both in terms of process and properties are presented. The new developments of high performance steel surfaces are highlighted.

A fast quenching equipment, the TWICE, has been installed on the continuous annealing line of Kessales in May 2002, to satisfy the ever increasing demand for high strength steels with a good formability. After more than two years of industrial operation, the TWICE has proven all its excellent properties, in terms of reliability of the equipment and quality of the steels produced, making of the C.A.L. of Kessales the reference tool for the HSS production in the Arcelor Group.

Through process control, from BOF down to finishing lines, has been developed and implemented. It features real time on line control of defects, risk assessment and the prediction of the mechanical properties. This innovative process control makes it possible to reduce drastically the standard work load of the Metallurgy and Quality Department. The experienced staff can then be appointed new ambitious objectives towards the industrial excellence: “The right product at the right time for the right cost”, “Meeting customer needs” and “Respect the firm's economic objectives”. To achieve this, business organization must be adapted. Key factors are intelligent listening to the final customer needs and process route optimization from the BOF to our customer facilities, paying particular attention to synergies between the hot and the cold mills.

The 4th Daughter Directive to the Air Quality Directive sets, for year 2012, a target value of 1 ng/m3 for the concentration of benzo(a)pyrene in ambient air. This target cannot be met at present in the ambient air of numerous coke plants. Operators are thus requested to take every reasonable measure in order to come closest to the desired air quality standard. Technical measures for minimizing benzo(a)pyrene emissions will focus on optimizing the pressure conditions in the oven chamber as well as on improving the sealing capabilities of coke oven closure facilities. The techniques for reduction of benzo(a)pyrene emissions, developed by Deutsche Montan Technologie GmbH, are presented.

The slag corrosion resistance of MgO-MgAl2O4, MgO-MgAl2O4-ZrO2, MgO-MgAl2O4-TiO2 and MgO-ZrO2 materials has been studied according to the slag corrosion extent and the change of slag chemical composition. The results were compared to those of the MgO-Cr2O3 refractory used for the RH low vessel. It can be concluded that, among the chromium-free materials tested above, the MgO-ZrO2 refractory will be better for the RH vacuum vessel.

In this study the microstructural characterization and the abrasion resistance of a series of Ni based alloys containing 10 at. % Cr, 5-15 at. % B and 5-20 at. % Si are presented. The formed hard components are borides of chromium and nickel (CrB, Cr5B3, Ni3B) and a silicon nickel compound (Ni5Si2) in a <Ni> matrix. These phases appear either in primary solid solution form or in biphased eutectic form or in secondary fine precipitates form. The loss of mass, the abrasion factor and the microhardness of the various phases versus time were measured. The best results are obtained for 10 at. % B and Si contents of about 10 at. %.

The increase of the demand for hot metal made it necessary toanticipate the relining of Rogesa No. 4 blast furnace. At the sametime, the furnace has been enlarged in order to reach a dailycapacity of 6,400 t. The work has been carried out under a consortium of Paul Wurth and SMS Demag with many subcontractingcompanies. The performances on the site have been verysuccessful so that the original schedule could be reduced from 99to 90 days. At maximum there have been more than 600 peopleworking on the site and above al1 without any accident. The totalbudget amounted to 60 M Euro for the furnace itself and to 20 M Euro forthe slag granulation system.

The zero-waste pilot plant was erected in Vítkovice (Ostrava, CZ) and 9 test campaigns have been performed to date (January 2004). The feasibility of the process with various by-products from carbon and stainless steel production, and from other important activity sectors (power plants, car dismantling companies) was positively assessed. Two different mineral products have been produced according to targets: clinker substitutes for cement production and metallurgical powders for secondary metallurgy. Attractive economic figures were calculated, especially for the treatment of stainless steel by-products.

To assess the impact of particulate emissions from Port Talbot Works on local air quality, a detailed mathematical analysis of ambientparticulate data collected in the borough over several years has been completed, with a special focus on the period following the stoppage ofn° 5 Blast Furnace in 2001. This work was done following the declaration of an Air Quality Management Area (AQMA) adjacent to PortTalbot Works, in order to tackle the high incidence of exceedances of the 24 h PM10 objective in this area.

On the galvanizing line in Desvres, Arcelor has implemented an innovative low temperature preheating cycle for the hot rolled strips. This made it possible to increase the line output without any major process modification but for the preheating that is carried out at a temperature on the order of 500°C. The arrangement of the direct fired preheating has been adapted accordingly, with new burners and the last zone is set at a higher temperature, to limit the oxidation of the strip.

Capacity of the ladles is in way to be increased in several steelplants for flat carbon steel products (Dunkirk, Florange). The new steel ladles have been designed, taking into account several key points: the stiffness and the service temperature of the steel shell, which is controlled by the geometry of shell reinforcements and by the efficiency of the thermal insulation layer; the stiffness of the lip-rings, which can be greatly improved by using steel plates protected by refractory concrete; the wear of the slag line in MgO-C bricks, which can limit the ladle campaign if vacuum tank degassing process is used for ULC steels production. Slag control is required. Numerous trials are also in way to limit the wear of the bottom impact zone of the steel ladle, including pre-shaped alumina-spinel cast bottom, in Arcelor Dunkirk.

Several parts of degraded organ pipes belonging to some organs produced in different periods (from the 18th to 20th century) and from different Italian geographical areas have been examined and investigated in order to identify the possible causes of the degradation phenomena. An analysis through DSC-DTA measurements has been performed to define the crystallographic transformation of the studied alloys and a metallographic analysis has been realized to point out the microstructural characteristics. The morphological analysis has been improved by SEM equipped with an EDS device which permits a quantitative chemical characterization of the intact zones and of the degraded ones. The presence of chlorides has been identified as the starting factor of the degradation phenomena.

Due to the new European Regulations and to the new material tests prescribed by the European Acceptance Scheme, most current materials for domestic distribution of drinking water will have to be substituted for. Performances of stainless steel, as compared with other materials, are highlighted considering sanitary aspects and fitness for purpose as well. The new press-fitting technique makes it possible to join stainless steel plumbing easily, thus alleviating the only difficulty with stainless steel installation. This opens the way for the development of stainless steel in drinking water distribution.

The Integrated Pollution Prevention and Control Directive (IPPC) published in the EU in 1996 is presented within an approach based on source-targeted measures. The Directive implementation is based on the granting of permits and it introduces new concepts like Best Available Technique (BAT), Best Reference Document (BREF) and Level Playing Field (LPF). The consequences for the EU steel industry are discussed.

An experimental study has been performed at CRM with impinging burners to heat quickly low carbon steels without oxidizing their surfaces. The thermal performances of various burners (maximum heat transfer of ~370 kW/m2 on impinged surface) were studied and compared to data collected from classical direct flame furnaces. Simulations permit to consider an interesting reduction of furnace size. The surface characterization indicates the possibility to heat steel strip without oxidizing up to 840°C. It would then be possible to anneal steel strips at higher temperature than it is actually performed in the direct flame furnaces.

The VAI Variable Speed Descaler takes full advantage from the use of variable speed pumps powered by inverter driven AC motors. Integration with strip tracking and feed forward pump control, together with direct application, allow to optimize the energy savings, to improve pumps life and to simplify the layout. Integration with flow and pressure feedback measurements at headers allows headers pressure tuning, nozzle wear compensation, process control with different “descaling recipes” as function of steel grade and main strip parameters, bar-to-bar adaptation of descaling parameters in case in-line surface inspection is present. Specific “descaling recipes” and pumping station design, together with proper mill scheduling, result in a new maintenance concept allowing to run the system without a stand-by pump, saving investment cost. First two references of this new system are at the hot strip mills of Ilva Taranto (HSM No. 1) (Italy) and of Duferco La Louvière (Belgium).