Distributed
in the UK by ROBOTECH DEVELOPMENTS Ltd
& HEWITT JEWELLERY EQUIPMENT LTD
VACUUM PRESSURE
CASTING MACHINES
for
PLATINUM &
PALLADIUM (Gold & Silver)
Designed around GALLONI'S unique patented High pressure
"PRESSOVAC" casting system giving the very best casting
quality results with minimal cost.
Pressovac
Pressovac Max
GALLONI'S electronic induction casting
machines for dental applications go back to 1948. Since then
continuous development for both dental and jewellery industries has
lead to the PRESSOVAC platinum, palladium casting machines,
which today gives jewellery manufacturers state of art technology for
platinum casting, which is generally known to be the most testing
jewellery precious alloy to cast.
GALLONI VIDEO
http://www.galloni-aseg.com/video/gseries/pressovac3deng.html
TECHNOLOGY - it is well known that electronic
induction melting is the best way for melting metals and with vacuum
melting a greater degree of homogenity and purity is achieved, thereby
exploiting all the metallurgical properties of the alloys.
Castings of high quality are formed under vacuum,
as molten alloys can reach the thinnest parts of the model and
solidify under pressure.
The results of this advanced technology can be
summarised as follows:
* higher casting purity
* greater melt homogeneity
* higher corrosion resistance
* easier casting of thin section items
* less reaction of molten melt with investment
* reduced shrinkage and gas porosity
CASTING MACHINE
RANGE
PRESSOVAC Casting
Machine - 120 grams pt , up to 200 grams silver capacity
& 150 grams gold capacity
Tabletop
machine, ideal for small volumes producing very high quality casting
of CAD designed and prototype produced waxes in any precious
metal, silver, gold, platinum, palladium and non-precious metals. High product yield of 50%+ (of the total weight of metal used), are typically achieved, thereby reducing money tied up in expensive
precious metals to a minimum. By a simple change of crucible and
machine settings, the
machine can cast platinum & palladium (silica crucible) or gold
and silver (graphite crucible). The machine's casting cycle is perfectly
calibrated to ensure good quality castings are achieved every time by
any operator for all metals. This is a very easy machine to use for anyone new to
casting.
Max
temperature - 2100 C
2.5
Kw single phase
max
flask size - 76 mm dia x 70 mm tall
Click
here to download the Pressovac PDF sales leaflet
PRESSOVAC MAX Casting
Machine - 350 grams pt , 500 grams
silver
800
grams of gold capacity
The
ideal production plant machine, with a 350 gm platinum capacity,
allowing a large number of pieces to be cast in one cycle. The machine
also has a large melting capacity for other precious alloys including silver, gold, palladium.
This
model comes with "touch" screen control making it
easy to change from one alloy to another, all alloy casting parameters
can be saved and re-used time and again to give very consistent
casting results.
Max
temperature - 2100 C
4
Kw single phase
max
flask size - 100 mm dia x 150 mm tall
Click
here to download the Pressovac MAX PDF sales leaflet
CONSUMBLES
Each machine comes with a comprehensive range of
crucibles, heating coils and accessories for each metal alloy.
Different crucibles, coils and accessories are
used for,
Platinum - high temperature ceramic
Palladium, Stainless steel - silicon carbide
Gold, Silver - graphite
TECHNOLOGY
Please follow this link to see further details
on the PRESSOVAC MAX from GALLONI -
http://www.galloni-aseg.com/en/prodotti/pressovacmax.html
Spruing - is designed to ensure the best
possible casting result is achieved using the Pressovac machines and
to minimise waste metal.
A typical conical type rubber sprue base needs to
be used, with sprue wax no thicker than 7mm diameter. This
combination will allow the best possible flow of metal, particularly
for platinum.
Very thin items should be mounted vertically (not
on a tree) using a 5 mm thin wax disk as the base.
If a two - part investment is used, the mould
will need to be dried out using absorption paper before the burnout
operation. Below can be seen the "Yoshida" system for
spruing using this powder.
Waxes are added to special sprue design, which is
positioned on absorption paper with a solid flask placed over the
assembly when completed.
After casting only the product and a small amount of
base are cast in platinum metal
This amount of sprue (shown in green wax) has been saved from
metal casting
Investing - can be carried out in a
specially designed "Vacuvest #3", which is designed
to mix the two part chemical binder/water with powder (link to
VacuVest web page).
Burnout - a special burnout cycle has been
created by GALLONI to ensure the best conditions for casting.
Casting technology - is based around the unique
GALLONI vacuum high pressure casting system, which ensures gases from
within the platinum and palladium alloys are expelled during melting
and pouring of the metal, thereby minimizing porosity.
The 3 bar pressure pouring system ensures the
metal pours quickly before freezing into the mould.
The casting operation is simple for
platinum, for example:
- before switching on the machine, ensure the
machine is set-up with the correct heating coil, and crucible assembly
for platinum, ensure the platinum cycle on the machine (Pressovac Max)
has been selected
- switch on machine, making sure the cooling
pump/system, compressed air, and inert gas are connected and
functioning correctly
- then load the crucible with 40 g of pt alloy
and melt until molten, then add further amount to maximum to be
melted, do this only when the flask has been added to the machine from
burnout furnace and start the Vacuum once pressure chamber has
been closed
- as soon as platinum has reached the required
casting temperature by visually observing along with the optical
pyrometer, press the "Cast" button, and the metal
will automatically be poured into the flask under 3 bar pressure.
Heating power will switch off automatically after 10 seconds.
- metal will solidify under inert gas pressure,
until the pressure is released automatically, allowing the pressure
chamber to be opened
The whole process takes only a few minutes to
complete and gives very consistent high quality results.
- retrieve flask for quenching
After quenching a Power blaster such as the Robo
Midi Blast can be used to remove most of the investment powder. (Link
to Robo Midi Blast page)
Before
After
