Shaping the quality
| Ravenna and Casalmaggiore (Italy). Here the global manufacturer Marcegaglia has located two production centres in which it processes high-value quality steel products dedicated to applications including building & construction, automotive and pressure equipment. Both these units have been recently upgraded with new state-of-the-art mills to widen further the productive range. We have visited the two plants. It’s a snowy day in Casalmaggiore (Northern Italy) when we arrive at the local Marcegaglia plant, the first large-scale carbon tube manufacturing centre established by the group, a few minutes’ drive from its Headquarters, whose covered surface was recently doubled. The very first feature of the plant is an integrated photovoltaic roofing (employing Marcegaglia PV panels) generating 2.1MW (corresponding to 2.000.000 kWh/year) electrical power to partially supply the manufacturing process. The unit here is dedicated to the processing of carbon steel hot rolled strip for the production of certified welded tubes and hollow sections, round, square, rectangular and of special shapes. We are here to visit the latest equipment additions. First of all, the new slitting line that allows to process high-thickness coils (up to 16 mm) increasing the whole manufacturing capacities up to 700,000 t/y (thanks to 5 lines). The new line is characterized by the presence of a robot-controlled blade changing station with pre-loader and blade depositer that allow to better manage the slitting program. Besides, counting on the new slitter, 3 tube mills for new dimensional range capacities have been added for diameter up to 406,4 mm and thickness up to 16 mm. Today the complete production range is manufactured within 11 lines reaching a manufacturing capacity of 700,000 t/y. Tube production has several certifications including CE marking and AD2000 for applications such as structures, pressure purpose, naval construction, automotive industry. The very latest addition is the ISO/TS 29001 quality system certification for the oil&gas sector. In addition to several chemical and mechanical tests on materials, the mills are equipped with state-of-the-art technology of in-line controls during the manufacturing process. A new heat treatment furnace has also been added to the plant and today the capacity of normalization, annealing and stress relieving in Casalmaggiore has been incremented to 200,000 t/y. Logistics plays a key role for Marcegaglia on a global level. According to this vision, Casalmaggiore plant was completed by an automated warehouse that spreads over 14 hall aisles and allows the automated storage and preparation of bundles to ship, avoiding the operator’s access to the loading bays. Moving to Ravenna (on the Adriatic coast) we are immediately astonished by the great area occupied by a well-organized coils storage system where raw materials is stacked and registered before being processed. Logistics plays a key role, here. Marcegaglia Ravenna is the group’s main hub: besides the coil storage area, the plant can count on a huge facility for receiving, storing, moving and shipping metal materials including 700 metres of harbour docks, privately owned and managed, finished with state-of-the-art concrete floor and coil cradles served by 5 cranes and an internal railway line. In Ravenna, the flagship equipment is the new galva-painting line: 200 metres of installation for cold rolled low carbon and HSLA steel processing with a manufacturing capacity of 350,000 t/y and capable of rolling strip 900–1,550 mm wide and 0.25–1.50 mm thick. The line carries out the complete paint coating process (pretreatment, primer & top finish) performing galvanized painted zinc coating from 60 up to 450 g/sqm total. Hydraulic automatic gauge control eliminates not only disturbances caused by the backup rolls, but also those caused by work rolls. This new line came in addition to the other 2 pickling lines, 3 cold-rolling mills, 50 annealing furnaces, 1 skinpass, 3 hot dip galvanizing lines and 1 pre-painting line. Focusing back on the galva-painting line, the system configuration allows to bypass the painting section when needed, in a way that is quick efficient and cost-effective. As well as flexibility which is, above all, the most important advantage coming from the installation of a combined line for galvanizing and pre-painting steel coils. Obviously, space optimization (only 200 mt instead of 360 mt required for 2 uncombined lines) and investment cost containment complete the advantages panorama. Focusing on technical requirements, the group chosen the NIR-system technology: a combination of: special Near InfraRed heat sources, extreme energy densities and special process and systems engineering allowing the fastest solution for the cure of finish coatings. Marcegaglia Ravenna technical laboratory has researched and developed more than 25 standards of resin organic coating on both sides of the steel coils: New solutions can be engineered based on new requirements. |
