5.2 Heater Assembly
The heater is a made of fiber ceramic insulating material with imbedded heat-
ing. The heater is made up with twohalves, each with a separate heating ele-
ment. The heating elements are wired in parallel.
The heater is primarily a radiating device and is rated for a maximum furnace
operating temperatureof 1100°C. Realize,however, that the higher the operat-
ing temperature, the lower the lifetime of the heater.Limiting th e number of
hours atthe extreme high end of the temperature range to only the time re-
quired for calibrationsincreases the longevity of your furnace heating element.

5.2.1 Equilibration Block Assembly

The Equilibration Block Assembly consists of 1) thetest well, 2) access tubes
and end plate, 3) the frontand rear guard blocks, 4) insulation on each end and
5) the center block. The center block is intended to stabilize the temperature
fluctuationsand to conduct heat between the test wells in order to equalize
them. The guard blocksshunt heat to the various probes to reduce heat loss out
the ends. The whole assembly is supported by a fused silica tube. All heated
materialsare fused silica, ceramic fiber, or Inconel (alloy 600).
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5 Parts and Controls
Heater Assembly
CutoutProbe
Back
IsothermalBlock
QuartzTube
Front
GuideTubes
ControlProbe
Figure2 Sectional Side View