Product Code: ICA13_2101

Laser-Welded Sandwhich Floor for Marine Container
Authors:
Jukka Siltanen, Rautaruukki Oyj; Hämeenlinna Finland
Ville-Matti Nurmela, Ruukki Metals Oy; Uusikaupunki Finland
Ilpo Maaranen, Ruukki Metals Oy; Uusikaupunki Finland
Presented at ICALEO 2013

A new type of floor structure for marine containers utilizes both the excellent properties of wear-resistant and high-strength steels produced by Finnish steel maker Rautaruukki and the advantages of laser welding. Wear-resistant steel has excellent properties that protect it against wearing and impacts. The high-strength steel can carry heavy loads even with small material thicknesses. Laser welding as a low heat input welding method, causes only minor distortions and a high welding speed is possible. In the study, two different laser-welded steel flooring types a closed steel sandwich structure and an open steel sandwich structure were manufactured and tested. The closed floor structure consisted of three main parts: a top plate, V-shape cores and a bottom plate. The open floor structure consisted of a top plate and V-shape cores. The top plates and the bottom plate of the floor structures were laser welded with a butt joint from two cut-to-length steel plates. The joint type for the cores was a lap joint. The weight of the marine container with the new floors was only 10% greater than the weight of a traditional container floor with steel beams and plywood plates on top of those. This is quite remarkable because the floor material has been changed from plywood to steel. Where applicable, the actual performance testing of the marine container has been carried out according the testing procedure of standard ISO 1496/1.