Abstract
Coiler drums are integral components of the Steckel mill reversing hot strip rolling
process. A Steckel mill produces hot rolled strip steel from cast slabs, which are heated
before being converted, via roughing, to a transfer bar, of which the thickness is
subsequently reduced to the desired gauge by means of a reverse rolling process
performed by the Steckel mill. Coiler drums are located inside two Steckel furnaces,
which are positioned on both sides of the mill stand. As the strip thickness is reduced
during each pass, the length increases. In order to obtain high rolling speeds and retain
temperature, the strip is successively coiled and uncoiled, under tension, onto and from
the heated coiler drums during processing.
As coiler drums have a high unit cost and a significant impact on the quality of the
finished product, coiler drum performance is important to Steckel mill operators. The
high cost is associated with the high alloy composition of the casting and the
specialised manufacturing process required for the production of coiler drums.
Deterioration of the coiler drum condition over its service lifespan can adversely affect
the quality of the final product, namely coiled strip. This investigation was therefore
undertaken to gain insight into coiler drum failure mechanisms, which will benefit
Steckel mill operators, mill suppliers and coiler drum suppliers.
Professor R.F. Laubscher