REFRACTORIES FOR THE GLASS INDUSTRY
OF REFRACTORY COMPOSITE MATERIALS FOR GLASS PRODUCTION
G. S. Rossikhina,
M. P. Shchedrin,
and N. N. Shcherbakova
Translated from Steklo i Keramika, No. 5, pp. 26 – 28, May, 2008.
When a lining consisting of large refractory parts is put into a working regime, it is important to know the in
crease in the temperature of the material in order to determine the assembly gaps and be confident that fracture
as a result of structural transformations will not occur during operation when the temperature gradient over the
thickness of a part increases. Comparative studies of the thermophysical properties of conventional fired fire
clay materials (tamped beam for the bottom of the melt tank, semi-dry pressed ShSU beam) and low-cement
concrete materials with VShS fireclay filler have been performed at the Semiluki Refractory Works. The ma-
terials BShBS and VShBO showed negligible change of the CLTE with increasing temperature in the operat-
ing range 600 – 1300°C.
There are indisputable advantages to using refractory
concrete parts in the lining of commercial high-productivity
furnaces for producing glass. First and foremost, these are
great freedom in designing parts with different shapes and
sizes, fewer seams in the refractory masonry because large
beams are used, mechanization, and continuity of the assem
bly of the lining as a result of the accuracy of the geometric
dimensions of even the largest parts.
In spite of all this, however, the main user problem,
which, as a rule, arises because of the properties of the bind
ing system of composite materials such as low-cement con
crete, is obtaining the correct setting of the apparatus govern
ing the heat – moisture regime when a lining made of unfired
concrete parts is put into and taken out of the working re
gime, since the heat-treatment temperature for such parts at
the manufacturer does not exceed 400°C.
Characteristically, when a refractory material is heated
its volume changes: a temporary change, which vanishes on
cooling, as a result of the thermal expansion of the material
and a residual change which occurs as a result of chemical
and physical transformations and, as a rule, happens when
the operating temperature of the material is higher than the
firing temperature of the material or when during firing of
the part the required holding time at maximum temperature
was not reached. The character of the volume changes de-
pends on the nature of the refractory material. Thus, positive
growth is characteristic for dinas-clay parts and negative
growth is characteristic for fireclay parts.
When equipment lined with large parts, such as the bot
tom beam in a glass-making furnace and the beam for the lin
ing at the bottom of the tin melt tank, is put into a working
temperature regime, it is very important to know the growth
indicator for the material in all directions in order to deter
mine the assembly gaps and be confident that the masonry
will not fail as a result of structural transformations during
operation with an increase of the temperature gradient over
the thickness of the part. Conventionally, such parts have
been made of fireclay by manual tamping or semi-dry press
ing followed by firing up to a temperature of at least 1300°C.
For refractory parts to be used in the lining of a float
tank, it is also necessary to combine low permeability for
gases and tin, i.e., low open and channel porosity, with good
thermal stability and the required thermal conductivity, since
the temperature differential over the thickness of the refrac
tory masonry at the bottom reaches 800°C.
It is known that the proneness of a refractory to crack
during temperature changes is a direct function of the CLTE
and an inverse function of elasticity and thermal conducti
Glass and Ceramics Vol.65, Nos.5–6, 2008
0361-7610/08/0506-0162 © 2008 Springer Science+Business Media, Inc.
Semiluki Refractory Works JSC, Semiluki, Voronezh Oblast,
Russia; Ogneuporkomplekt JSC, Moscow, Russia; Saratov Insti
tute of Glass JSC, Saratov, Russia.