Which advantages offers chipless
cutting of tubes
Chipless cutting of tubes and pipes means
deletion of washing procedures. Thereby tremendous cost
Keywords: No chips when
cutting tubes and pipes
30.000 to 80.000 cuts with one
can be realized, e. g. reduction of working time during transportation,
placing the tube cuts into
the washing plant, unloading and
But also the washing plant as such
can be expensive: Service, washing medium, ecological duties, and
In addition chipless cutting saves raw
material. A sawing blade (1-2 mm) produces chips, which are lost
raw material. (30.000 x 1 mm are 300 meters !!)
knife rotating around the tube is the pre-condition for tearing and
breaking whereas the tube is not
cut through totally. Using
the tear/break-procedure there is, contrary to sawing, no inner burr.
that in many cases it is not necessary to de-burr.
With an aditionally rotating pressure roll the tube end may
Which advantages offers a processsing of coil-ware compared to rods?
There results a major material saving due to
the elimination of starting and end pieces. In addition
supplied in coils is in most cases less expensive. For copper tubes e.
g. the price may be
lower by up to 20%.
of rods is avoided, thus reducing the circle time by about 10 %.
a single shift operation based on copper tubes up to 3.000.000 tube
cuts may be produced (de-
pending on tube size and wall
A further advantage is the less
expensive storage of coils, its compact dimensions and no cases.
3. Which raw materials can be processed from coils?
For copper tube diameters of up to 35 mm
a wall thickness of 1,5 mm are possible.
tubes from AL-alloys can be processed from coils.
tubes, especially high grade, can be processed from coils if the
diameters are small.
4. How is uncoiling done?
The coils are placed on a driven
uncoiling unit. The uncoiling speed is stepplessly adjustable. For
set-up times in some applications a double uncoiler may be advisable.
The tube is not
directly supplied to the tube cutting
machine but is placed onto an air-suspended balancing roll.
balancing roll guarantees a smooth, secure uncoiling in interaction
with the servo drive of the
tube cutting machines' feeder.
5. What about the straightness and diameter tolerances of the
The tube coming
from the coil is calibrated and straightened by 18 straightening rolls.
meter tolerances after straightening will be at +
0,05mm, the straightness of tubes at 1 mm per meter.
tubes are very well processed with regard to uncoiling, in addition it
has an interesting
pricing. However, often a certain
hardness of the material is requested. Soft copper tubes can be
by straightening to a yielding point of R0 = 180 N/mm˛. Due to the
exact stepless adjustable
straightening rolls this hardening
procedure can be executed.
7. How are the
set-up times when changing the coils?
using the same diameter of tubes between the used coil and the new one,
the coil end and coil
start can be connected using a
crimper. This work including placing the new coil to the uncoiler needs
about 5 - 7 minutes. The connection between the coils is
recognized by the tube cutting device and can
be cut off
When using different coil diameters in
addition 3 chucks have to be exchanged and the cutting diameter
to be adjusted as well as the straightening rolls be exchanged. The
adjustment of the straightening
device to different
diameters is done very easily. Without loosenig any screws the
straightening rolls can be
drawn off and the new rolls
placed. The adjustable straightening rolls are provided with an
absolute scale so
that registered adjustment values can be
regulated without locking device pretty easily. The whole set-up time
reach about 10 - 12 mins.