The
use of gravity casting into permanent moulds
overcomes the major problems of sand casting,
contamination, poor finish and low dimensional
tolerances. However, the chilling effect of the
mould leads to cold laps, shuts and misfeeding
becasue the metal cools too quickly. Again only
by adequate gating and riser can this be
overcome resulting in a lower yield.
Substituting the metallostatic head by means of
pressure or centrifugal action solves the yield
loss problem and gives castings with a superior
finish and dimensional accuracy.
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 The
Centracast System
In 1984 we commenced
the design and development of a machine that
involved centrifugally spinning gravity dies.
Centracast Westside Engineering have proven that
for the castings weighing between 100g - 8kg,
vertical centrifugal casting offers several
distinct advantages over the traditional methods
of low, high pressure and gravity die casting.
|
 The
graph shows a graph of production rate (castings
per hour) vs. cast weight (kg) using CENTRACAST
technology. The figure presented compares
favour-ably with a low pressure diecaster,
particularly as the yields are in excess of 95%.
The technology not
only produce high production rates, but the tool
change over time is one third that of a
camparable low pressure die. Production runs of
up to 10,000 unit have demonstrated that the
tooling cost for the vertical centrifugal
technology are substantially less than that of a low
pressure die, both in capital and maintenance. |
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