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aerospace industry l engineering
Optimal machining for resilient materials
WALTER milling tools set new
standards in the aerospace industry
Walter M3255 porcupine
milling cutter for roughing titanium
Aluminium alloys have played a crucial
role in aerospace production for a long time. New requirements and attempts to
reduce the weight of components as
much as possible has led to innovations in
aluminium machining and alloy types. The
main challenges in the sector are the large
volume of removed material, which for
many components can be up to 90 %, as
well as new, extremely light, yet robust
aluminium alloys that are difficult to machine. It is also necessary to take material
costs into consideration. Although aluminium alloys are cheaper than CFRP materials, their cost is still a major factor in calculating the cost per component.
Aluminium alloys – still in vogue d
"Until recently, many industrial experts
predicted that carbon fibre reinforced polymers (CFRP) will become ever more important for aircraft production. The advantages of these materials are clear - they
are light, yet astonishingly strong. That
makes them ideal for use in a branch of industry that needs to handle both incredible growth and increasingly strict requirements for energy consumption and
pollutant emissions," explains Dirk Masur,
Walter's aerospace component manager.
"However, CFRP materials also introduce
problems, since their machining is difficult
and expensive. The search for alternatives
brought aluminium alloys back to the
centre of attention. Current forecasts are
based on the assumption that the volume
of machined components will grow considerably until 2020."
The aerospace industry is on the rise. With revenue of
around EUR 40 billion, this branch of Germany's industry
reached its highest total in history in 2017, a 6 % increase
compared to 2016. German aircraft manufacturers have
invested 10 % of their turnover into research and
development (source: BDLI). The aerospace industry
counts among the pioneers of new materials and
machining processes. Tool manufacturers, such as
machining specialist Walter, keep in step with the
dynamism and innovativeness of this branch of industry.
To that end, Walter maintains a strong partnership with
research institutions such as the Institute for Technology
and Innovation Management at Hamburg University
of Technology. This cooperation has led to the
development of BLAXX M3255 porcupine milling cutter
for titanium-aluminium alloys. Another addition to the
product range is the M2131/M2331 ramping milling
cutter, which allows users reliable, precise and efficient
machining of aluminium alloys.
special 2020
T+T Technika a trh
Designed for high-speed cutting d
In the majority of structural components,
the large volume of removed material is
caused by the complexity of the shape. It
is typically the result of the need to create
pockets of various sizes and depths,
which must be machined directly into a
"raw" blank. The only economically viable
processing method is high-speed cutting
(HSC), where materials are milled at speeds of up to 3,300 m/min. Lower cutting
speeds lead to a build-up on the cutting
edge which makes milling tools wear
down faster until the machine eventually
overloads and stops. The total cost per
part ends up increasing as a result. In order to achieve the cutting values required
by suppliers of components in the aerospace industry, however, which are much
higher than average cutting values, it is
necessary to design special machines and
tools. Walter, a specialist in machining,
has introduced special ramping milling
cutters designed to meet these requirements: the M2131 and M2331, with the
latter being designed specifically to meet
the requirements of Makino machines
with speeds of over 30,000 rpm. The ability to choose between two sizes of indexable inserts allows users to achieve a 15
or 20 mm depth of cut - ideal for ramping
milling and pocket milling. Thanks to the
extra hard, yet smooth PVD coating, there
is nearly no build-up on the insert's cutting
edge, making the edge extremely resilient
to wear. The unique design of the insert
seat protects the insert from the high centrifugal forces created during high-speed