Welcome to Sestao

1994/03/01 Rodriguez Ibabe, Jose Maria Iturria: Elhuyar aldizkaria

• Materialak

Finally, the metamorphosis of Altos Hornos de Vizcaya, the AHV, is being diluted. Much debate and doubt remained behind, but in the future they still appear dark. However, analyzing this metamorphosis should take into account some criteria. For many years the AHV factory has been considered as the example of the Biscayan industry. Thanks to the number of workers, the production of tons, the history of a century, etc., for many the horneros were considered as strength thermometers of an industry. However, almost 25 years ago the giant began to weaken.

In the new plant there will be no horneros or mineral or coke. On the contrary, the new raw material will be scrap, that is, as in the rest of the mills of the Basque Country, in Sestao electric furnaces will be used to obtain steel. However, compared to other plants, in Sestao a completely new technology is going to be launched. This system will reduce the price of steel production, but at the moment there will be difficulties in the daily production of this technology. Therefore, the road will not be easy, but we are convinced that the advantages that will be obtained in this workshop in the short term will be of great help for the renewal of the rest of the mills of the Basque Country.

Until now the steel and its subsequent forming have been separated. In conventional boilers, liquid steel solidifies into ingots, with relatively large weight and dimensions for each ingot. Steel is not sold as ingot and to have a suitable size and shape hot forming is applied. For this it is necessary to reheat the ingot (up to about 1200ºC).

In order to reduce this process, a few years ago a continuous lamination was developed. The steel does not solidify in ingot and the dimensions of the hardened billet with another system are much lower than those of the ingot. To obtain a product of the same dimensions, compared to conventional pouring, this procedure is cheaper, so in most factories in the Basque Country there is this system in operation. However, the billet is cooled in the air and then heated to have the proper dimensions and shapes to apply the hot forming.

The new plant, both the pouring and the hot forming, which will be installed in Sestao, will be carried out successively, that is, before solidifying completely will begin the forming of the steel. The system, called "intensive procedure", will be one of the first in Europe. It can undoubtedly be considered one of the most significant advances in steel production in the last twenty years. However, it also has its disadvantages. Labour will be significantly reduced and the social importance of this new workshop will not be compared to the old AHV.

Finally, another point should be taken into account. The "intensive procedure" technology is being developed entirely outdoors (especially in Germany). To master and adapt all this, the technicians here will have enough work, but if not achieved, technological dependence can be a danger for the future.