RUSSULA NEWSLETTER No. 11

RECENT PROJECTS
Three consecutive projects at Gerdau Cartersville
Following the recent modernization of the DC drives
of the bar mill, Russula has won a contract for the 4
strand continuous caster and complete bar mill control
revamp at Gerdau Cartersville in GA, USA.
The projects will be implemented in two phases during
planned shutdowns. In the first phase, one strand of the
continuous caster and the bar mill will be
commissioned in September 2015. The second phase
consists of the revamping of the other three continuous
caster strands, scheduled for December 2015.
A multi-phase revamp approach allows mills to upgrade
obsolete control equipment and minimize mill
downtime, which reduces the impact on production.
Rolling mill drive upgrade completed in just six days
The first project, implemented in December 2014, consisted
of upgrading the main DC drives of the bar mill
from ABB DCS600 to DCS800. The entire mill downtime
for the uprade was only six days. Even though the
upgrade was from the same drive family, due to the
various sizes and configurations, it was necessary to
propose solutions for each case, seeking the best technological
improvement while minimizing the investment.
The proposed solution is based on using DCR upgrade
kits, which replace all electronic drive control while
keeping intact the power stacks. The kits are highly
modular, allowing the upgrade to be accomplished
quickly. The main benefits were:
- Gerdau Cartersville mill obtained the high
performance offered by ABB DCS800 drives
without having to change the power stacks, thus
optimizing the economic investment.
- Replaced obsolete equipment and software, which
was expensive to maintain due to the high price of
spare parts replacement for discontinued
equipment.
- Established a standard and transparent
communication path between the PLCs and
standard drives, expanding the communication
capabilities of these systems with other external
control systems.
Control system upgrade for bar mill and continuous
caster scheduled for September 2015
This second project is currently under development
and consists of the upgrade of the existing control
system and HMI architecture for the bar mill. The
current ABB AC450 PLCs with the ABB AS500 SCADA
operator inferface will be replaced with the ABB
AC800M series and Wonderware Intouch. Russula mill
control will be implemented for the entire line from the
first stand to the cooling bed.
New DC drives supplied by Russula for the sideguards and
screwdown of the DUO two high stand revamped in 2011
Gerdau Cartersville mill produces a line of angle bars,
profiles and flats with diameters from 150 to 300 mm
7 Russula Newsletter No. 11 April 2015 - Copyright © by RUSSULA S.A.