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COVEREX - 707
An exothermic
powder, which is applied to the feeder head. When the
exothermic reaction of the COVEREX-707
is complete, the burnt out materials
expands three times and has a strong insulating effect
which reduces heat loss by radiation. Used for all grades
of Iron and Steel castings / Ingots especially when feeder
heads indicate a requirement for a medium sensitivity
exothermic Anti-piping compound.
FUNCTIONS
Anti-piping compounds are used to prevent the considerable
heat loss to atmosphere that can take place from uncovered
risers. As long as the surface of the open topped feeder
remains liquid, atmospheric pressure exerts its powerful
influence in the feeding of casting. Unfortunately often
it is lost when skulling of the metal acts as a barrier to
atmospheric pressure and the riser then, only has its own
gravitational mass to promote feeding.
THERMAL PROPERTIES
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Final
Insulations Value At 40 min : 0-40-0-16 Cal/Cm²/Sec
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Net
Heat Loss at 20 min : 80 Cal/Cm²/Sec
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Peak of
Exothermicity 4 to 5 minutes
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Max.
Temp. attained : 1600 to 1650°C
INSTRUCTIONS FOR USE
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Pour
casting to within approximately 25mm of the riser.
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Place
required quantity of COVEREX-707
on the top of the riser so as to
provide a cover of about 25 mm in depth.
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allow
the exothermic reaction to proceed.
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top up
with more metal if necessary.
ADVANTAGES
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Better
feeding hence sound castings.
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Easy
applications COVEREX - 707
is supplied in ready for used
conditions.
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Reduction in scrap more that offsets small cost
involved.
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Particularly useful where box parts or casting design
makes risering difficult.
STANDARD PACKING
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