Freedom Beams

I was asked to accompany the Web TV team for part of the episode, filmed in Luxembourg. They all were great people to work with. The idea of the episode was to give a view of the entire industrial process from the scrap yard to the shipment. Differdange is where the jumbo beams for the Freedom Tower and the corresponding beam blanks are produced. A few shots were also made in the AOB site in Esch-sur-Alzette where the R&D, sales and technical advisory departments are based. The selection of the Differdange site to produce the sections of the Freedom tower is a fantastic achievement. This is the merit of all those people who, in the past and presently, built and run that plant.

To create the Jumbo Beams that are ultimately used to construct the famous Freedom Tower there are several steps ….
- selection of the raw material (the mix of scrap among the qualities available) that will constitute the base of the steel alloying
- loading of the electric arc furnace with the scrap
- melting process: the scraps are heated at ~1600°C, the temperature at which the steel is in liquid phase
- ladle furnace-purification and alloying: at this stage the steel is purified by removal of some impurities which are detrimental for the material properties. Alloys are also added: some carefully selected chemical elements are necessary for the expected material quality
- continuous casting: the liquid steel is poured in an open ended mould in which the solidification process will be initiated. After completion of the solidification the semi-finished products are cut to length for further processing. These semi-finished products are called beam blanks and have the shape of a dogbone.
- hot rolling: the beam blanks are reheated to 1250°C and deformed in rolling stands to obtain the final shape of the jumbo beam. A precise thermal path is defined for the rolling and cooling of the jumbo beam: this will allow to obtain the expected material quality.
- testing: the product is controled (dimensions, surface and internal soundness, chemical composition, mechanical properties,…) and compared with the requirements
- shipment of the certificated material