Crushing, Grinding and Screening Equipment
REBUILDING AND HARD-FACING CRUSHER
Initial Rebuild and Hard-face of Shells
To relieve stress before hard-facing, new Manganese
shells should be operated for a short period of time.
After this brief initial period, during which wear
should be limited to approximately 3/16 in., a regular
schedule of roll upkeep should be established. If rolls
are worn less than 3/1 6 in.. they can be hard-faced with
recommended alloys. If excessive wear has occurred,
FIGURE 2-62. Wear Measurement
the worn rolls must be rebuilt to size and contour
of Crusher Roll Shells
before hard-facing. The amount of wear can be
measured (Figure 2-62).
There are certain procedures that are common to roll
rebuilding whether welding is done manually,
semi-automatically or automatically; the success of the
rebuilding and hard-facing operation is as dependent
upon them as upon subsequent welding techniques.