STEEL + TECHNOLOGY 04/2019 EXTRACT

STEEL PROCESSING | 77
functions which used to be performed in
separate steps on different machines.
Thus non-productive times are significantly
reduced.
Besides a turning tool holder, the carriage-mounted
tool unit can accommodate
an ultrasonic testing probe, and drilling
and milling heads. With these
attachments the sleeve can firstly be finish-turned,
followed by ultrasonic testing
of the individual ring segments. This
assures that whenever a portion of a
sleeve does not meet the required specifications
this will be identified at a very
early stage and the corresponding material
can be stopped from being further
processed
Boris Marcukaitis, sales engineer at
Dango & Dienenthal, sees great benefits
for his customers: “Sawing instead of turning
alone provides tangible benefits in
terms of material saving, quality and efficiency
improvement, and cost reduction.
On top of this, our new machine is able to
perform further process steps without
having to reclamp the workpiece. In this
way, we enable our customers to manufacture
rings on just one single machine,
while in the past they usually needed three
separate ones.”
The functional principle
The sleeve is firstly positioned on the
turntable and clamped. At the top end –
where the first ring is to be cut – the sleeve
is fixed by means of height-adjustable
clamping arms. Thanks to this arrangement,
the height of the sawing kerf is held
precisely constant throughout the cutting
process.
Simultaneously, the outside of the
sleeve can be finish-turned and inspected
over its entire height. Then the first ring is
sawed off. It will not drop back onto the
sleeve rim because it is securely held in
place by the clamping arms. From there
the ring can be lifted up and removed by a
crane with ease. Afterwards, the clamping
arms will be lowered to the position of the
next ring to be cut.
Milling, drilling and testing can be executed in the same clamping position (Picture:
Dango & Dienenthal)
The use of a turntable provides the
advantage that the rings can be cut while in
a horizontal position. This makes the loading
of the machine and the removal of the cut
rings much safer. Even while performing
the last cut, the ring remains securely fixed.
Technical data
The clamping equipment can handle
sleeves with diameters between 800 and
more than 3,000 mm, and heights of up to
1,000 mm. It can accommodate sleeve
weights of up to 20,000 kg and cut ring
weights of up to 3,000 kg. By cutting with
a sawing blade, a radial cutting depth of up
to 550 mm can be achieved.
What is more, by sawing, rings with
heights of only 15 to 20 mm can be produced.
Such small ring heights cannot be
produced by groove turning. By means of
special clamping devices, such as “lost”
jaws, it is even possible to cut rings of less
than 4.5 mm height.
• Dango & Dienenthal Maschinenbau
GmbH, Siegen, Germany
The prototype at Klaaßen Maschinenbau
with that time exposed circular saw blade
(Picture: Dango & Dienenthal)
STEEL + TECHNOLOGY 1 (2019) No. 4