LONG PRODUCTS BULLETIN - SMS Meer GmbH

World record
40 Newsletter No. 3/2009
Long-product mills
Unique rolling mill for 700,000 tpy of rebars
Stefana, Italy: World record
for rolling of straight bars
The bar mill of Stefana S.p.A., Italy, built by
SMS Meer came on stream in mid-2008 and
is unique in view of productivity and product
quality. The mill reaches full capacity at all
dimensions of the product mix. Now, the
production line at Ospitaletto in northern
Italy has set a new world record on July 2009
for the rolling of straight bars on the cooling
bed: the new mill produced salable coils
made of rebars at a diameter of 8 mm and an
average real speed of 40 m/s over several
hours during shift operation.
This performance is equivalent to a production of single bars at
double speed, i.e. as if 80 m/s would have been achieved. A target
limit value which had formerly only been planned has now
actually been reached and further improvements can soon be expected.
At a production of 8-mm rebars with slitting and the two-strand
HSD ® system and at a rolling speed of 40 m/s billets are required
to such an extent that the maximum furnace capacity of 106 t/h
is almost reached.
VCC station. Coil bundling and tying system.
Two-strand HSD ® system for supreme performances. The facilities
for a high performance of this future-oriented mill are
mainly two slitting lines in combination with a two-strand HSD ®
system as well as the control system with software developed
by SMS Meer.
The basic principle of a two-strand HSD ® system is to finish-roll
bars in two six-stand and V-shaped finishing blocks and to cut
them with two state-of-the-art high-speed disc type dividing
shears. Then, the bars are processed over their entire length in
four braking pinch-roll units (two for each strand) and two dual-rotating
channels installed on top of the entry table of the cooling
bed. Only one bar per tooth is deposited on the cooling-bed
rakes to make sure that a clean layer is available for the bundling
and tying systems.
Largest furnace of its class. Other mill components worth mentioning
are a walking-hearth furnace for the heating of 16-m-long
square billets at a cross-section of 160 mm x 160 mm, which is
one of the largest of its class, as well as two of our patented VCC
(Vertical Compact Coiler) facilities.