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Air Products' new technology brings quality
and productivity improvements to cold rolling industry
23rd March 2004 — Today, Air Products unveils its new technology, Air Products cool rolling technology, to the European Metals Processing industry. Developed in partnership with C. D. Wälzholz, in Hagen, Germany, this new process help strip metal cold rollers to increase surface quality and productivity as well as to reduce scrap, during the final pass of rolling metal strip. It also brings significant improvements on safety standards and the working environment.
Air Products cool rolling technology uses spray bars to distribute liquid nitrogen (or other industrial gases) at low temperature, preferably between –170°C and –196°C, over the metal strip as it enters the rolls. In conventional cold rolling processes, emulsions or oils also work as a lubricant, reducing heat generation by reducing friction. Liquid nitrogen, in contrast, has little lubricating effect; instead it removes frictional heat thanks to its very high heat capacity. Liquid nitrogen then evaporates, leaving no residue. It therefore creates a less oxidising atmosphere around the rolling nip.
Cold rolling technology can be retrofitted to existing mills or integrated into new installations.
Results from C.D. Wälzholz have shown that conversion to Air Products cool rolling technology has reduced the costs of final-pass rolling by around 25%, thanks to an increased line speed of up to 200%, and reduced rejects, due to rust, to zero.
“This new technology is a significant step for the cold rolling operation. We have been using it successfully on our production lines for the last two years. During this period, we have realised cost savings and increased productivity as well as enhanced surface finish,” said Mr. Dr.-Ing. Hans-Toni Junius, managing director, C. D. Wälzholz.
Erwin Esser, customer technology manager metals, Air Products Germany, explains: “Air Products cool rolling technology is an environmentally sound technology, presenting an alternative to both wet and dry rolling during the final roll. Compared with wet rolling processes, benefits include improved working conditions, reduced rejects and lower capital outlay and running costs. Cold rolling with nitrogen, as experienced at C.D. Wälzholz , can eliminate the need for post cleaning of the strip, thus allowing significant increases in productivity and reductions in downstream processing costs. Compared with the dry rolling process, the adoption of Air Products cool rolling technology brings significant increases in rolling speeds without roll sticking or surface quality problems.”
Air Products, the world’s only combined gases and chemicals company, has been a significant player of the metals industry for over 50 years. With experience in ferrous casting foundries, production and processing of iron and steel as well as non-ferrous metals industry, Air Products focuses upon a wide range of innovative, technical solutions to maximise efficiency and reduce costs. |
