is that tools maximize process reliability and
support a high-quality finish.
The production of new wheels, particularly
roughing and finishing operations, can be
completed with Dormer Pramet’s standard
assortment of RCMX inserts. Numerous sizes,
grades and chip breakers provide options for
every workpiece material and cutting condition.
As well as the manufacture of new wheels,
there is a continuous need for wheel reprofiling
through a wide assortment of machining centres
from various manufacturers.
Dormer Pramet’s range of holders are suitable
for some of the market leading manufacturers,
including Hegenscheidt and Rafamet machines.
Since 1950, Hegenscheidt-MFD has installed
more than 2,000 wheelset reprofiling machines
around the world.
Both companies use special-purpose wheel
lathes for railways, metro, tram, and other lightrail
transit systems, along with heavy-duty single
and double-column vertical turning lathes, large
bridge-type milling machines, horizontal lathes
and special machines.
Dormer Pramet’s historical cooperation with
machine producers and rail repair services has
enabled the company to develop a wide range
of standard and custom solutions for increasing
productivity and reducing costs typically
associated with these processes.
This means that the renovation of railway and
tramway wheels can be achieved with their
standard assortment of inserts (LNMX, SNMX,
CNMX), grades and chip breakers. Also, it offers
a range of cartridges with pocket protection,
allowing for a comprehensive and versatile
solution for depth of cuts between 1.0-16.0mm.
A Dormer Pramet customer in Ukraine, for
example, required support with the re-profiling
of railway wheels made of steel with a high
hardness of 450 – 615HB. The LNMX30 insert
with RF chip breaker and T9315 grade achieved
a high level of durability and was significantly
more productive than an equivalent supplier,
machining 12 wheels compared to the
competitor’s five.
Another success was with a specific machine
builder for wheel set reprofiling in Poland. The
customer wanted to resolve a chip breaking
issue when machining hardened steel 800 –
900mpa. Once again, the LNMX30 insert was
used, this time with the TF chip breaker and
T5315 grade. This combination achieved 50%
longer tool life compared to competitors, but
also significantly improved chip breaking on the
perpendicular surface.
Dormer Pramet’s T5315 grade is a versatile
option designed for turning grey and ductile cast
iron, as well as various steels, including hardened
steel. It is suitable for roughing and finishing with
medium to high cutting speeds and capable of
both continuous and interrupted cut. This makes
it a very versatile option in challenging machining
conditions.
Base plates and coupling machining
Another area of activity is the machining of
bearing or base plates - the connecting element
which ensures the rail is attached to the railway
tie or sleeper. This operation requires profile
milling of this part where customers demand
high productivity, while at the same time,
respecting specific production limitations and
materials. Milling cutters and drills are ideally
suited to base plates production.
Finally, a coupling or coupler is a mechanism for
connecting rolling stock to a train. The design of
the coupler is standard, and almost as important
as the track gauge. It needs to offer flexibility and
convenience for all rolling stock to be coupled
together. The equipment that connects the
couplings to the rolling stock is known as the
draft gear or draw gear.
The manufacture of couplers is an example of
the type of niche cutting tools available to wagon
producers from Dormer Pramet. Its many years
of experience has resulted in various levels
of support for the manufacture of axle boxes,
center plates, bogie frames and fenders.
Dormer Pramet’s approach to systematically
work in partnership with producers of these
parts has allowed them to further refine and
develop their cutting tool offer.
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