NEW AREAS FOR APPLICATION OF REFRACTORIES AT THE NIZHNY
TAGIL IRON AND STEEL WORKS JOINT-STOCK CO.
É. A. Visloguzova,
L. V. Serova,
and A. G. Lyzhin
Translated from Novye Ogneupory, No. 4, pp. 98 – 99, April, 2004.
Effective operation of a metallurgical plant is determined
by many factors, chief among which are quality, durability,
and cost of the refractory materials used. Improving the qua
lity of metal products is impossible without the proper use of
high-performance wear-resistant refractory materials. How
ever, quality costs money, and the cost-to-quality ratio is an
issue of great concern for the manufacturer.
At present, the market offers for metallurgy a wide range
of refractory products available both from domestic and for
eign manufacturers. It is a gratifying fact that domestic
refractories, both in quality and service, are becoming more
competitive with foreign products; however, this is mainly
true of unshaped and vibrocast components. Available from
domestic manufacturers are low-cement and alumina-con-
taining mixtures which are used, as rammed or cast refrac-
tory components, for the lining of blast-furnace runners, vac-
uum degassing chamber branch pipes, blast-furnace bottoms,
steel-teeming ladles, intermediary ladles, etc.
Tuyeres and nested nozzles for argon blowing (available
from domestic manufacturers Dinur JSC and Ferro Balt Plus
JSC) have successfully undergone trials at the NTISW. These
facilities were found to conform nicely with the requirements
placed and their performance characteristic were not inferior
to foreign analogs, with the benefit of a lower cost.
However, domestic refractories for the lining of conver
ters, steel ladles, degassers, and stopper nozzles are inferior
in durability to those available from foreign manufacturers.
To a lesser extent this is a concern for converters considering
that, with the converter’s lining, emphasis is primarily placed
on maintenance measures and on properties of the refractory
material used to form the protective scull. At the NTISW, be
fore the slag blow technique was put in service, the durability
of the lining from a foreign manufacturer was typically
35 – 40% higher, occasionally by a factor of 2. The use of
slag blow technique and appropriate maintenance measures
(for example, local hot repair) made it possible to improve
the durability of the domestic lining to an extent comparable
with that of the foreign; at present, it is 2600 – 3000 heats.
When choosing materials for protection the lining from
wear, it is important to determine the service time, or durabi
lity, which, when exceeded, will incur higher maintenance
and repair costs. Normally, these differ from plant to plant; at
the NTISW, the durability of the lining has been 3000 –
3200 heats. There are routes which, properly implemented,
will make it possible to improve the lining durability and to
save refractory material costs.
Durability of the lining of steel ladles is mainly con
trolled by the quality of the refractory used and by the judi
ciously designed (differentiated) pattern of the lining. Cur
rently, linings prepared from foreign refractory materials
show better performance characteristics. The lesser durabi-
lity of domestic linings is mainly associated with insufficient
performance of the binder. Ethylene glycol and powdered
phenolic binder (PPB) showed a nonuniform distribution in
the refractory mixture and, consequently, failed to provide
the required stability of properties in full measure. Further-
more, PPB is sparingly soluble in ethylene glycol, which in-
creases the rejection rate. The binding properties of PPB and
candidates for its replacement will be considered elsewhere.
The properties of refractory components prepared using the
conventional binder and a new composite binder developed
in cooperation with Oksima Joint-Stock Co.) are compared
in Table 1. Pressure-molded components were neat in ap
pearance, with well-defined edges and faces.
The newly-developed composite binder was tested in the
lining of a ladle furnace and the results were compared with
those for the conventional binder. With the former binder, the
amount of wear was smaller (by 12 – 17%); however, the
cost increased by 2.2%. Currently, a commercial-scale batch
of components is under way at the NTISW to confirm these
Refractories and Industrial Ceramics Vol. 45, No. 4, 2004
1083-4877/04/4504-0277 © 2004 Springer Science+Business Media, Inc.
Nizhny Tagil Iron and Steel Works (NTISW) Joint-Stock Co.,
Nizhny Tagil, Russia.
Compressive strength, MPa 42.3 73.0
Open porosity, % 4.7 2.0
Apparent density, g/cm