PRODUCTION AND EQUIPMENT
USE OF BASIC COMPOSITION TORCRETE MIX IN CBCM TUNDISHES,
DEVELOPMENT OF NEW COMPOSITIONS
S. M. Aksel’rod,
V. V. Ryashin,
E. I. Pospelova,
and I. G. Maryasev
Translated from Novye Ogneupory, No. 5, pp. 16 – 25, May, 2013.
Original article submitted September 26, 2012.
The working layer of a CBCM tundish lining provides unit operation for ten hours of metal pouring. Develop
ment stages are provided for second generation torcrete mix compositions of the trade mark Dalgun. Results
are given for petrographic study of the working lining layer of periclase and periclase-forsterite compositions
Keywords: periclase, torcrete mix, tundish, CBCM.
CBCM tundishes have been considered for a long as a
vessel for distributing metal over channels and maintaining
steel pouring rate with replacement of a steel-pouring ladle.
Currently a tundish is a metallurgical unit destined for inde-
pendent functions. First it serves for metal refining. The
working layer of a tundish lining provides continuous pour-
ing without ladle replacement; the working layer of a lining
should not be a source of non-metallic inclusions in steel.
The advantages of a lining of unmolded refractories based on
magnesium oxide is generally accepted.
Since the end of the twentieth century in the stage of in
creasing CBCM productivity the lining layer of tundishes in
CIS metallurgical enterprises has been replaced by torcrete
mixes based on compositions produced by firms in Germany,
Austria, Turkey, Slovakia and other countries, instead of
pieces of aluminosilicate objects. A certain amount of
torcrete mixes has been manufactured in Russian refractory
enterprises, in particular OAO Kombinat Magnezit. Use of a
torcrete mix has made it possible to reduce labor expenditure
and time for preparing tundishes for pouring, and to reduce
the proportion of non-metallic inclusions in steel.
Recently there has been a rapid increase in multiple
pouring (melt on melt), and corresponding specifications for
a mix, especially for section CBCM. In 2008 series of more
than 20 melts was accomplished in more than 10% CIS met-
allurgical enterprise CBCM, but in 2011 it was already 30%
of these CBCM (we are talking about CBCM with
stopperless steel pouring and with use of a device for rapid
replacement for the lower nozzle dispenser in a steel pouring
channel). For a number of enterprises a requirement for pro-
viding multiple production of more than 40 or more melts is
the standard. World experience shows that from the point of
view of operating duration and resolution of the problem of
minimum inclusion formation in a tundish periclase compo
sition mixes are preferred; mixes of periclase and forsterite
composition are recommended with greater series produc
tion. The source of forsterite is normally olivine, and rarely
fired dunite, added to a periclase mix composition.
Within the set of specifications for lining from periclase
mixes, often torcrete mixes, there is also the possibility of
applying mixes to the strengthening layer of a lining (con
crete of repeated use with a life of 1000 melts or more) for
the minimum time, retention of its continuity in the drying
period, and warm-up for a lining and minimum time required
for drying a torcrete layer (normally up to 5 h), and mini
mum thermal conductivity in the working condition. In the
operating period of a torcrete lining (consumable lining) it
should not be sintered through the whole thickness, espe
cially with the strengthening layer of a tundish concrete lining.
Refractories and Industrial Ceramics Vol. 54, No. 3, September, 2013
1083-4877/13/05403-0169 © 2013 Springer Science+Business Media New York
Representative of OOO Gruppa Magnezit, Moscow, Russia.
Representative of OOO Gruppa Magnezit, Magnitogorsk, Russia.
OOO Gruppa Magnezit, Satka, Chelyabinsk Region, Russia.