Extremely flexible cooling of heavy plate to expand product portfolio

The X-Roll^® MultiFlex-Quench is part of a new, energy-efficient heat treatment line SMS supplied to the subsidiary of Salzgitter AG. Commissioning of the X-Roll^® MultiFlex-Quench, which is designed to implement extremely flexible cooling strategies, now permits Ilsenburger Grobblech GmbH to expand its product portfolio by particularly demanding heavy plate grades, among others.

The new heat treatment line will process more than 200,000 tons of heavy plate per year, with the main focus on the production of wear-resistant and high-strength quenched plates. The line is designed for plates with thicknesses between 5 and 175 millimeters and widths of up to 3,550 millimeters. With plate lengths between 4 and 26 meters, the plates have a maximum weight of 32 tons. The material grades to be processed include high-strength carbon steels, highly wear-resistant steels, steels for offshore and pressure vessel applications as well as case-hardened and quenched/tempered steels.

With the X-Roll^® MultiFlex-Quench, SMS has established in the market an innovative cooling technology that provides distinctly more options than conventional cooling lines and allows any cooling strategy from extremely slow cooling to quenching with freely selectable cooling-stop temperatures to be implemented by means of switchable pressure ranges. Thanks to the variable settings, the MFQ can handle a much wider product range than conventional quenches can. The plates are hydraulically clamped by roller guides thus ensuring optimal flatness, especially of thin plates. This is confirmed by the excellent results of manual flatness measurements at Ilsenburger Grobblech, which are based on flatness measurements of a plate taken at different measuring points in the process.

The most important requirement for homogeneous cooling and optimum product properties of the plates is high temperature uniformity during both plate heating and the tempering process that follows quenching. For this purpose, SMS supplied two state-of-the-art roller hearth furnaces equipped with energy-efficient heating systems and modern low-NOx burners for low-emission operation.

SMS also supplied an X-Roll^® MultiFlex-Leveler T for the heat treatment plant. While providing proven functions, this latest type of leveler sets new standards in terms of final flatness and residual stress distribution in the material. Among other components, new back-up rolls for maximum load transfer were developed specially for this machine type and tested on SMS group’s own test stand. In addition to variably selecting the strategy to remedy even complex flatness deviations, the quick-acting leveling roll adjustment system offers the advantage of E-mode operation (Extended Roll Mode) which greatly increases the leveling range of the machine. A bending system suited for specific leveling gap adjustment, a load balancing system for the individually driven main drives and a highly dynamic main adjustment system complete the machine profile of the X-Roll^® MultiFlex-Leveler T.

Besides the X-Roll^® MultiFlex-Quench, the X-Roll^® MultiFlex-Leveler T and the two furnaces, SMS group supplied a shot blaster, a primer line and a water treatment plant, all complete with X-Pact^® electrical and automation systems. Powerful X-Pact^® process  models, including a material model, ensure the correct setting of the equipment and the achievement of the desired material properties. The scope of supply also includes ancillary equipment such as plate conveyor system, cooling beds and plate feeding and centering equipment.