TPT July 2017

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T E CHNOLOG Y
JULY 2017 61
Non-round is no problem for Bend Tooling
TAKING on a rotary draw bending
project involving square or rectangular
(non-round) tubing has often been
considered a risky proposition, but by
following a few simple guidelines and
using the correct tooling, favourable
results can be obtained. To ensure that
the CNC or NC tube bender has the
power to take on the required forces, it is
best to add one inch to the major width
of the material and choose a machine
with a capacity of that value or greater.
For example 2" x 3" rectangular x 0.12"
WT tubing would require a bender that
has a capacity to bend 4" diameter x
0.12" WT round tubing.
Furthermore, to avoid committing to
a dangerously tight bend radius, it is
usually wise to make sure the inside
radius (ISR) is not less than 1.5x the
tube’s horizontal width.
The use of a special bend die actuator
isacommondeterrent whenapproaching
non-round tubing applications, but with
the availability of ‘tapered leaf’-style
tooling, such actuators are no longer
a requirement. If necessary, mandrel
and wiper tooling may also be used in
conjunction with tapered-leaf tooling.
Bend Tooling Inc – USA
Fax:+1 616 454 9958
Email:
Website: Bending square tubes