TPT September 2013

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Technology News
September 2013 51
t-industry.de
for the industry
Bending process improvements
TEBUNUS Tube Bending, The
Netherlands, is regularly challenged
by customers requesting use of the
minimum of the required tube material.
Two recent projects resulted in the
development of improvements in the
company’s bending process.
The company developed the
capability to bend copper tube products
from a coil on its bending machines. No
extra material is required for overlength,
and less material is wasted. A customer
had requested the company to produce
copper tube spirals with a diameter
of 8mm, and 0.4mm wall thickness, in
large volumes.
Instead of loading the bending
machine manually or via a buffer, up
to 1.5km of material is available on
coil. For other projects, coil material is
possible with a diameter up to 22mm.
Tebunus bends 180° with high values
on wall thickness reduction and ovality.
This development allows the reduction
of costs and lead-time of tube products
with a total length of more than 6m. It
is possible to design very long tube
products without welds.
Another customer requested a needle
shaped heat exchanger tube for a green
energy project. The requirements on
the ovality (<8%) and wall thickness
reduction (<15%), in combination with the
tube material and radius of < 2D, were
demanding. To avoid expensive heat
treatment after bending, it was important
to keep the stress in the material as low
as possible.
Tebunus designed tooling with which
the product could be bent without welds.
The tooling was based on a bend block of
two parts, which enabled bending of the
180° product with the required accuracy
to meet all dimensions. The choice of the
bend radius was an optimum of hardness
of the tube after bending, minimised
tube material, machine possibilities
and dimensional requirements. After
preparing for six months, the project was
a success: on time and within budget.
Tebunus Tube Bending can bend pipe
and tubes in ferrous and non-ferrous
materials. The company can bend carbon
and stainless steel from 2 to 114.3mm
in diameter, and aluminium and copper
up to a diameter of 168.3mm. Tebunus
designs and produces its own bend
tooling, and has a wide range of tooling
in diameters and radii available on the
shelves, enabling immediate production
upon request.
Tebunus Tube Bending BV –
The Netherlands
Fax: +31 72 504 48 00
Email:
Website:
180° bends