The technology of slag processing by rotary cylinder at Baosteel has many advantages, such as short flow, higher efficiency, more safety, lower consumptions etc. Processed slag has stable properties and small but symmetrical granules, lower contents of free-CaO, and it can be used directly in many areas.

Over the last decades the steel industries worldwide haveevolved more or less independently from each other, inthe EU and in North America in particular. A competitivecomparison of two different Basic Oxygen Furnace (BOF)maintenance operations is presented, discussing various costfigures in a theoretical case study.

The newly developed VAI-CONR Chem system allows to determine continuously the chemical composition of liquid steel in any metallurgical vessel. It represents an enormous potential for process improvements. After extensive laboratory testing, the system was sucessfully tested at an industrial vacuum degassing plant. At the beginning of 2003, it will be installed at a new AOD converter.

A new filler material, a stabilized ferritic welding wire, has been developed for the joining of the stabilized ferritic stainless steel sheets increasingly used in automotive exhaust systems. The joints obtained in the GMAW and GTAW processes behave at least as well in service as those obtained with austenitic filler wires. The new welding grade can also be applied to produce heterogeneous assemblies.

Low temperature degradation (LTD) of iron oxides was investigated with the aim ofunderstanding how natural iron ores degrade under different conditions. Minimisation ofthis degradation would increase the acceptance level of natural iron ores as feedmaterials without prior beneficiation. In addition to temperature and reduction gascomposition, sample positioning in the reduction furnace and sample’s original weight werealso found to influence LTD. Samples placed in the top reaction zone of the furnace, whichhave the first contact with the reducing gas, were found to degrade 1.5 times more thanthose in the middle and bottom reaction zones. In addition, they presented a wide range ofsize in the disintegrated particles than those in the middle and bottom reaction zones.Furthermore, the samples with an original weight equal to or greater than 5 g, had adisintegration extent of less than 10%. Therefore, if the reduction gas comes into contactwith a certain material first, before contacting the iron oxide, it may serve to reduce onLTD during reduction. Furthermore, in laboratory conditions, the occurrence of lowtemperature breakdown of the natural iron oxides can be minimised by using samples with anoriginal weight equal to or greater than 5 g.

The principle of mass flow AGC of tandem cold mill as wellas advanced mass flow AGC are introduced and analyzed.Based on advanced mass flow AGC, the effect of laservelocimeters to jointly control strip's thickness is analyzed.On the basis of the advanced mass flow AGC systemof tandem cold mill in Baosteel, the characteristics andmerits of advanced mass flow AGC in application of laservelocimeters are analyzed in detail.

High strength steel is an interesting alternative for making steel structures more competitive. Its production and use in Europe is small compared to markets as Japan and USA. It would be of mutual benefit for producers and users if the use increased. The paper gives examples of successful use and a state of art concerning design of such structures. Possibilities for further development and obstacles to be overcome are also discussed.

Recent studies have shown that in certain situations, usually described by mixed lubrication models, a continuous ultra-thin film could separate two solids, even at the scale of asperities. In this paper, the consequences of this assumption are examined in the case of cold rolling geometries. The tribological behaviour is derived from the resolution of the Reynolds equation. The influence of the rheological parameters of the lubricant and of the existence of a cavitation zone is discussed.

A new on-line guidance tool has been implemented to help the mill operator with the achievement of a thickness performance that meets the ever more stringent requirements for DWI material. The tool makes it possible to analyse the causes of thickness defects that are originated by the HSM or by the tandem mill.

The European Waste Framework Directive (2008/98/EC) explicitly specifies the hierarchyfor waste management: prevention, preparation for re-use, recycling, other recoveryactions, disposal. When selecting waste management options, this waste hierarchy should befollowed. A deviation can only be justified by Life Cycle Thinking (LCT) on the overallimpacts. The application of this principle in the Flemish waste management practicetriggered the need for evaluation of treatment options for several waste streams.Alternative treatments were evaluated for waste batteries, used frying oils and waste oil.The evaluation methodology combined life cycle assessment with technical and economicalviability criteria. These cases show that LCT does not allow to establish a “generalpriority order”. In each case reasons for deviation from the standard waste hierarchycould be given, but also none of the evaluated options can be considered as the best. Theevaluation showed that the priority is largely dependent on location-specificcharacteristics of inputs, outputs, processes and installations and that the establishmentof local and global environmental priorities always implies a value choice. In thispresentation, we will present the results of the three cases and provide a methodologicalframework for life cycle thinking in waste management policy.

Deposition of Ni3P nano-scale layer on B4C nanoparticles in fourcontents of sodium hypophosphite as reducing agent including 5, 10, 15 and 30 g/l viaelectroless coating were done to investigate the effect of reducing agent content on thecoating thickness of deposited Ni3P. The bath pH and temperature was 5.5 and 85°C, respectively and the coating time was 25 min. The powders were characterized bytransmission electron microscopy (TEM) and the phases present were revealed by X-raydiffraction (XRD). Nickel and phosphorous contents of the coatings were measured byinductively coupled plasma analysis (ICP). The results revealed that by increasing thereducing agent content from 5 g/l to 30 g/l the average coating thickness increased from19 nm to 28 nm. Although the increasing effect of adding sodium hypophosphite content waspreserved, there is a critical amount for sodium hypophosphite content to increase thecoating thickness.

To precede the energy and environmental demands, a follow-up ofthe coke oven batteries was made, to identify the probable causesof pollutants generation and thermal losses. The results of thefollow-up of the in/out gases of the coke ovens led to a change ofthe traditional operational practices, aiming at reducing the airemissions and the energy consumption of the coke ovens.

The mechanical properties of a 10.5% chromium stainless steel striphave been determined as a function of the cold rolling reductionratio. The best formability properties after annealing are associatedto the higher cold deformation. This is a consequence of the texturedevelopment and through thickness homogeneity. The recristallizedgrains mis-orientation has been studied with the CSL approach andthe coincidence index.

A novel web-based Decision Support System (DSS) for condition monitoring and continuousimprovement of steelmaking production efficiency is presented in this paper. Productionefficiency was measured and modelled through Key Performance Indicators (KPIs), which areassigned on-line to a single product (coil) and identified at different facilitiesthroughout the integrated route. The systemic nature of the DSS system boosts theintegration of every agent included in the decision chain of the company. It assuresmulti-agent decision convergence and the transformation of process information and expertknowledge into profitable results. The first case study is presented.

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.

Stainless steels have sustained a continuous growth for these 50 years, based on their outstanding corrosion resistance properties. Their corrosion performance has been ever improved for a large range of environments. New grades with higher static or dynamic mechanical properties afford high quality parts at lower cost with modern fabrication technology. In the future, stainless steel should find further application in the transportation and in the water distribution industries. This growth might be impeded by the EU classification of alloys with over 1% nickel. Attention that is focused nowadays on nickel, may later on be drawn upon all metallic alloys, whose distinctive features should rather be acknowledged and which should benefit from the support of a common strategy to be agreed upon by all stakeholders.

Oxygen usage has played a crucial role in the ongoing EAF processimprovement and has enabled furnace operators to optimize thechemical energy input, reaching unprecedented efficiencies and productivity.This article will present the fundamental principles governingthe design of an optimized chemical energy system throughscrap oxy-cutting and melting, decarburisation, post-combustionand slag foaming. It will be illustrated with industrial results obtainedat the Vallourec Mannesmann Saint-Saulve site, where a PyreJetTM and ALARCTM PC system, using the newly designed DRAGON Panel, has been recently commissioned.

Une démarche de développement d’un modèle probabiliste à deux échelles pour la fatigueHCF des aciers est proposée. Elle est basée sur l’utilisation de mesured’auto-échauffement sous chargements cycliques et est validée sur la base de la prévisiondes courbes de Wöhler d’un acier dual-phase pour différents rapport de charge.

Pour améliorer la tenue mécanique à la fatigue polycyclique des matériaux de fonderie, laCompaction Isostatique à Chaud (CIC) peut être utilisée. Elle consiste en un traitementthermomécanique des pièces moulées afin de refermer, complètement ou partiellement, lesdéfauts initiaux qu’elles contiennent. On propose ici d’utiliser des mesuresd’auto-échauffement sous chargements cycliques et un modèle associé pour caractériser legain en tenue à la fatigue apporté par le procédé CIC sur un alliage cupro-aluminium defonderie.

As regards conditions in the mould, Continuous Casting of 400mm thick slabs can differ from conventional slab casting. Specificfeatures of thick slab casting are reported, concerning heat fluxes,both integral and local. Local heat flux has been determinedthrough an instrumented mould along with thermal modeling ofthe copper plate. Integral heat withdrawal data are compared withdata from conventional slab casting. The effect of steelcomposition on integral and local heat extraction has beenevaluated and interpreted in relation to residence times in themould and to the relevant thermal resistances. The influence oftundish temperature on superheat in the mould and on heatremoval was quantified. Oscillation mark depth and mould powderconsumption have been related to heat withdrawal. Crackingdefects were characterized in dependence on mould heat fluxdensities.