TOOLING CUSTOMISED CUTTING FOR HEAVY DUTY MACHINES
method and has a hardness of up to 85
ShC. The outer shell is 50 to 90 mm thick,
while the rest of the roll consists of a core
material that is much softer, having a
hardness of between 38 and 45 ShC. This
mixture of hard roll and soft journal material
also required the use of a variety of cutting
materials, such as silicon nitride, mixed
ceramic, carbide and CBN, all of which are
standard in the Ceratizit product portfolio.
Machining involved a wide range of
machining operations, such as turning,
grooving, milling, drilling, deep hole drilling
and thread cutting.
The Weingärtner mpmc series is designed
speci cally for these applications and this
horizontal turn-mill centre can be used to
machine components with diameters of up
to 2,000 mm, machining lengths up to 15 m
and a maximum weight of 80 tonnes.
Equipped with a turn-mill head and fully
automatic interchangeable machining units,
enabling complex parts to be produced on a
single machine in a cost-effective manner.
“One of the features of the mpmc for roll
machining is its two CNC workpiece loading
aids,” notes Exenberger. “Apart from these
loading aids, it also uses a CNC-controlled
steady rest.”
Another feature of the machine that has
a direct impact on the tool design is its
B-axis. “The B-axis enables the angle of the
tools and the required cutting depth to be
continually adapted to the current machining
situation, allowing us to obtain very high
feed and productivity gures. This advantage
Milling of a key face using
the MaxiMill A271 face-mill
is driven home by the fact that the turning
tools can be moved as required in both
directions. In addition, the likewise existing
Y-axis allows us to position the cutter over
the tool axis, which signi cantly increases
tool stability,” Ceratizit’s Hofegger explains.
The extreme hardness of the material
and cutting depths of up to 20 mm are the
main challenges faced by the tools when
machining the rolls. The non-homogeneous
nature of the material can also play a role.
The machining times, service life and high
degree of process security are clearly the
decisive factors, as far as machining is
concerned. Against this background,
Ceratizit assembled a tooling package that
includes turning, grooving and milling tools,
as well as systems for drilling, thread milling
and tapping – with all the tools coming from
the agship brands Cutting Solutions by
Ceratizit, Komet, WNT and Klenk.
The cutting inserts LNMR 50, SCMT 38
and SN 25, with cutting lengths of 50, 38
and 25 mm, respectively, are available for
users involved in heavy duty turning. For
grooving, the HX system with groove widths
of between 16 and 60 mm is used, so that
the required contours can be produced.
Among the areas that require milling are key
faces and bore radii. “For these applications
we use tools from the AHDM series for
heavy duty cutting and AHFC for high feed
cutting, as well as the MaxiMill A271 facemill
and special radius milling cutters,”
reports Peter Stebele, process manager for
heavy duty machining at Ceratizit Austria.
The MaxiMill high feed milling cutter
(HFC) is a key tool in this area, due to its
excellent productivity. Fitted with 10 inserts,
this cutter offers extremely high feed rates
per tooth, paired to shallow cutting depths
to achieve a high level of productivity. And
because of these shallow cutting depths,
the roughing operations performed by the
HFC milling cutter give the optimum
preconditions for the nishing of transition
radii on key faces. For the nishing of key
faces, Ceratizit employs its VHM end-mills
and CBN-equipped nish milling cutters.
When it comes to drilling, Ceratizit can
produce diameters up to 155 mm and
depths up to 60xD, with the range split
between its MaxiDrill MD900 indexable
insert drills, which are used across the
entire range of diameters from 12 to
63 mm, and solid carbide tools for
smaller holes.
With the initial turnkey package accepted
by Weingärtner’s customer, the mpmc
machines will be dismantled and shipped to
their destination, where the customer will
install them before carrying out nal
acceptance trials. Specialists from
Weingärtner and Ceratizit will be in
attendance, as both companies agree that a
comprehensive, machining-oriented and
professional service offering is vital
nowadays in regional markets. Especially as
a complete provider for heavy duty
machining applications that is looking for
follow-up projects.
The B-axis in the mpmc allows the approach
angle to be adapted to the required cutting
depth when turning, thus increasing the
feed speed
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