A new manufacturing
process at its Gloucester
production facility meant the
abrasives division of a
manufacturer of
advanced ceramic
materials needed to
replace large raised
hearth furnaces that
had reached
the end of
their useful
life.

The
application
called for a
rapid cycling
batch furnace
capable of de-binding and
sintering 100kg of graphite
matrix with a ceramic
powder inclusion at up to
1000°C, under a reducing
atmosphere of nitrogen and
hydrogen.

The solution provided by
Carbolite did not need an
afterburner; a 600 x 1200mm
Inconel 601 retort was used
to contain the nitrogen/
hydrogen atmosphere.

Inconel-coated catch
trays were added to the
retort to capture any
process
material that
might fall
from the
load. The
nitrogen/
hydrogen
reducing gas was premixed
and below the
explosive limits for
hydrogen.

As uniform heating of the
load was critical, a 3-zone
control system compatible
with NADCAP 2750 D, Class
2, was installed.