PRODUCTION AND EQUIPMENT
PRODUCTION ASPECTS OF THE MANUFACTURE
AND OPERATION OF TORCRETE MIXES
V. I. Artamonov,
A. A. Kondrukevich,
O. V. Bogdan,
and Yu. L. Goloperov
Translated from Novye Ogneupory, No. 7, pp. 23 – 26, July 2009.
Original article submitted April 9, 2009.
Production aspects of the manufacture and operation of torcrete mix MAGMS 85 are considered together with
its main properties, i.e. transportability, efficiency during application to the surface of an intermediate ladle re
inforcing layer, and also torcrete layer life. Results are provided for practical industrial tests of a torcrete mix
with several versions of binder and the effect of them on the time for passage of a mix through an Engler
viscometer is determined.
Keywords: torcrete mix, lining working layer, reinforcing layer, intermediate ladle, steel continuous casting,
Improvement of metallurgical production technology, in
particular an increase in continuous steel casting, and also
toughening of the requirements for its quality, leads to an in-
crease in the demand for modern refractory materials for lin-
ing CBCM intermediate ladles. An important element of the
lining of an intermediate ladle is the working layer material.
In contemporary practice in order to manufacture the work
ing layer there is use of torcrete mixes, for whose service
strict specifications are laid down. It is necessary to obtain
quite a strong and porous heat insulation coating, and here
the coating material should not contaminate the metal being
poured with non-metallic inclusions, and in dismantling the
residual layer should be separated easily from the reinforcing
layer of the lining, without harming it. The main advantages
of torcreting are the high level of material used (~90%) and
simplicity of the process. A disadvantage of the method is the
fact that the thickness of the first layer is 20 – 30 mm. With a
low moisture content the coating separates, not managing to
form a dense layer and with a high moisture content it flows
away from the lining surface .
Currently OOO Metpromsnab provides four grades of
torcrete mixes MAGMAS 72, MAGMAS 78, MAGMAS 85,
and MAGMAS 87. The greatest demand by users is for
torcrete mix MAGMAS 85, that is intended for the working
layer of a lining of intermediate ladles during pouring of or-
dinary and alloy grades of steel. The application temperature
for the torcrete mix is up to 1700°C. A torcrete mix consists
of sintered periclase with an MgO content in the original
product of not less than 91%, olivine, plastifying and binding
additions in order to improve adhesion, transportability dur
ing torcreting, and a reduction in the possibility of creep and
peeling of the mix during application to the surface of a rein
forcing layer of the lining of an intermediate ladle. Introduc
tion of cellulose and expanded basalt fiber reinforces the
thixotropic and strength properties of the torcrete layer
formed during drying under natural conditions for the pri
mary stages of heat treatment , and it also reduces thermal
conductivity and softens the drying conditions for the
torcrete mix that considerably reduces crack formation. After
torcreting intermediate ladles may be held in reserve without
a limit on time and temperature of the surroundings.
Torcrete mix life is determined by the quality of the orig
inal periclase, i.e. the MgO content within it, the degree of its
sintering, the content readily-melting components, and also
the grain size composition. With torcrete application thick
ness of 60 – 80 mm its life is 15 – 20 h of continuous pour
ing, that is provided by monitoring indices, and also the sta
bility of the grain size composition and MgO content in the
MAGMAS 85 torcrete mix (Fig. 1).
Theoretical research, laboratory studies and test-indus
trial work has shown that the optimum grain size composi
Refractories and Industrial Ceramics Vol. 50, No. 4, 2009
1083-4877/09/5004-0258 © 2009 Springer Science+Business Media, Inc.
OOO Metpromsnab, Kolomna, Moscow Region, Russia.
OOO Ogneupor-Komplekt, Moscow, Russia.