February
2006
High-emissivity
Coatings for Improved Performance of Electric Arc Furnaces
Paul C. Sheil (left),
senior application specialist — primary steelmaking,
North American Refractories Co., Middleburg Heights, Ohio
(paul.sheil@naref.com), and Thomas R. Kleeb (right), manager
— product technology, Harbison-Walker Refractories Co.,
Moon Township, Pa. (tom.kleeb@hwr.com)
High-emissivity
coatings based on NASA technology were developed to adhere
to all ferrous alloys and have been applied to several water-cooled
roofs on EAFs. Use of this coating can lead to energy savings,
higher productivity, lower maintenance costs and lower capital
costs.
Influence of Carbonaceous Materials on Slag Foaming
Behavior During EAF Steelmaking
Veena Sahajwalla (left),
Mahfuz Rahman (center), Lan Hong and N. Saha-Chaudhury (right),
School of Materials Science and Engineering, University of
New South Wales, Sydney, Australia (veena@unsw.edu.au); and
David Spencer, OneSteel, Rooty Hill, Sydney, Australia
This
study reveals the carbonaceous materials that generate the
most significant foam and, in turn, provides a guideline for
selecting materials for slag foaming in EAF steelmaking. Analysis
of the volume change during slag/carbon interactions is presented.
Optimization of Nucor Steel–Hertford County’s
Consteel® and DC EAF Operations
H. Mark Adjei-Sarpong (left),
melting and casting supervisor, Mike Fox (second from left),
melting and refractory supervisor, Bryson Trumble (second
from right), meltshop electrical maintenance supervisor, and
Jeff Powers (right), melting and casting manager, Nucor Steel–Hertford
County, Cofield, N.C. (msarpong@nucorhertford.com, mfox@nucorhertford.com,
btrumble@nucorhertford.com, jpowers@nucorhertford.com)
In
September 2000, Nucor Steel’s second Consteel® and
DC EAF melting facility was commissioned at the Hertford County
plate mill. The improvement projects are discussed, as well
as the optimization of the process and operation.
Recycling MgO-C Refractory in the EAF of Mittal Steel
Lázaro Cárdenas
R.G. Lule Gonzalez
(top left), process engineer — EAF and LMF, F. Lopéz
Acosta (top right), process engineering superintendent —
EAF, LMF and CC, and R. Rodriguez Tapia (bottom left), refractories
manager — EAF and LMF, Mittal Steel Lázaro Cárdenas,
Lázaro Cárdenas City, México (ruben.lule@mittalsteel.com);
and A.N. Conejo Nava (bottom right), professor, metallurgy
department, Morelia Technological Institute, Morelia, México
(aconejo@itmorelia.edu.mx)
Metallurgical
trials to define the effects of refractory recycling on energy
consumption, melting time, flux consumption and refractory
consumption are reported. The method of preparation as well
as the method of injection are also discussed.
Improved Bearing Design for the Electric Arc Furnace
at TAMCO Steel
Joel Reilly (left), manager
of maintenance and construction, TAMCO Steel, Rancho Cucamonga,
Calif.; Walt Kusnier (center), project manager — heavy
industry, NSK Corp. Ann Arbor, Mich.; and Carl Casanova (right),
manager — field services, NSK Corp., Santa Fe Springs,
Calif. (casanoc@nsk-corp.com)
When TAMCO’s EAF slewing ring bearing failed, steel production
came to a grinding halt. With smart planning and preparation,
however, TAMCOwas able to realize significant cost savings and
a reduced amount of lost production.
Simulation of Nozzle Clogging During the Continuous
Casting of Aluminum-killed Steel
Luis
Trueba Jr. and Kent D. Peaslee, Department of Metallurgical
Engineering, and Jeffrey D. Smith, Department of Ceramic Engineering,
University of Missouri–Rolla, Rolla, Mo. (kpeaslee@umr.edu)
Nozzle clogging is a common problem associated with the casting
of aluminum-killed steel. For this reason, a casting simulation
apparatus was designed to measure the effect of metallurgical
and refractory factors on nozzle clogging. Measurements taken
with the apparatus were used to calculate a clogging factor
(CF). The CF provides a quantitative method of evaluating
the rate of accretion formation. This paper evaluates the
effect of aluminum level, holding time before casting, and
nozzle diameter on clogging. Microscopy of nozzles used in
the simulation indicated that the accretions in the simulation
nozzles were reasonably similar to those found in industry. |
