Page 68 - Glass Machinery Plants & Accessories no. 4/2018

REFRACTORY MATERIALS
Refractory materials

FURNACES AND CHECKER
BRICKS
Fuel-fired furnaces in the glass
industry typically utilize checker
brick to improve efficiencies by
taking advantage of the excellent
heat exchange properties inherent
in ceramic materials. As the fur-
nace exhausts through the check-
er pack, the bricks are preheated
by the waste gases, providing a
source of energy to preheat the
combustion air when the cycle is
reversed. Regenerator efficiencies
can be affected by a variety of fac-
tors, from pack design to regen-
erator size. The materials utilized
in regenerators must be able to
withstand many different forms
of attack, including corrosion by
alkalis, silica, and sulphates, as
well as thermal shock and creep.
The selection of refractory materi-
als is critical to the operation and
life cycle of the regenerator.

Top checkers
This zone has an atmosphere
laden with alkali vapours and
solid batch carryover (CaO,
SiO2). High temperature cycling
and oxidizing/reducing effects
are also considered. HWI prod-
ucts for this area:
®
t 5VnJOF 98 DM High alumi-
na (corundum) with excellent
thermal shock resistance
®
t /BSNBH 98B Burned 98%
MgO with a forsterite bond
®
t /BSNBH VZ Mag-zircon com-
position with a forsterite bond
Middle checkers
5IJT [POF IBT UFNQFSBUVSF nVD-
tuations that are considered rela-
tively mild. Solid carryover is low
and less reactive because of the
lower temperature. The atmos-
phere is rich in alkali vapours and
some deposition can occur.
®
Super Narmag B Burned 96%
MgO with improved creep resist-
®
ance and Narmag B Burned
95% MgO re the products that
HWI provides for this zone.

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