stories on hard material matters - Ceratizit S.A.

World innovation: machining of
aluminium wheels now
without coolant
Benefit from savings with the new MAC tool from CERATIZIT
One of the special fields of the carbide expert CERATIZIT
is aluminium wheel machining. The recently developed
MAC system now allows the complete dry machining of
wheels without refitting machines. In this way CERATIZIT
once again is able to support their customers in the
automotive industry when it comes to the decisive topic
of cost reduction.
Conventional cooling in the field of aluminium wheel
machining through cooling lubricants is cost intensive.
Both the recycling of the chips and the coolant causes
considerable costs. While machining a wheel between
four and six kilos of swarf are produced. The recycling
costs are about 20 cent per kilo or approximately one
euro per wheel. For tens of thousands of aluminium rims
where dry machining is applied instead of wet machining
attractive saving is realized very quickly. With the latest
world innovation MAC from CERATIZIT, aluminium rim
producers can save money, optimize their profit and
distinguish themselves from competitors.
Ingenious: MAC cools utilizing the Joule-Thomson effect
“There were already various external air cooling
systems available in the market, however, their effect was
satisfactory to a limited degree. The nozzle was too far
away from the tool, too much cold air was lost,” explains
Michael Steiner in charge of the development of
the new MAC tool at the CERATIZIT development
department.
With MAC the CERATIZIT research department has
solved this problem. The cooling unit is directly integrated
into the CERATIZIT tool. The compressed air from the
machine goes through the tool into the MAC unit and is
then cooled to minus temperatures through a physical
effect known as Joule-Thomson effect. Then it imme-
diately hits the insert and the work piece.
This causes the air to be divided into a warm and a cold
stream (depending on the setting). The cold air exits on
the front of the insert through the lateral holes on the
tool. The air temperature on the cutting edge is then in
sub-zero range and efficiently cools both work piece
and tool. About 6 bar and 400 l/min capacity are the
prerequisite
MAC
The cold air reduces the temperature of the swarf and
enabling the tool to decrease and in a lot of cases
ideally avoids the tendency of adhesion of aluminium.
The cooling intensity depends on the quantity of air
supplied, its entrance temperature, the quality of the air
and the tool settings of MAC.
The CERATIZIT programme for dry machining
Currently the following grades are available for dry
machining of aluminium wheels:
• CTP4115 (PVD –TiAlN lubricating layer; K10)
• CTD4110 (medium fine diamond grains; DP-K01)
CTP4115 is a tried and tested PVD coating with good
low-friction properties. Its advantages can mainly be
seen when machining aluminium alloys with low silicon
content (Si ≤ 3 %) in combination with strong built-up
edge.
In grade CTD4110, PCD (polycrystalline diamond) being
an extremely hard cutting material is characterised
by high abrasion resistance and long service life. This
grade is particularly suitable for aluminium alloys with
increased silicon content (Si ≥ 12 %), for polish turning of
mirror faces and the machining of high-quality wheels
and components in aluminium.
The newly developed MAC system from CERATIZIT now allows the
complete dry machining of wheels without refitting machines.
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