TPT September 2016

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72 September 2016
T E CHNOLOG Y
High-output annealer for stainless steel tubes
PLASMAIT GmbH has introduced its
largest annealer for stainless steel tubes
to date.
The new HPA60 annealer features
60kW plasma power and is able to
anneal up to 250kg (550lb) of austenitic
stainless steel tubes per hour. It is
designed for OD range of 1/ 8" to 1/2".
The output of the annealer is
comparable to the outputs of similar
induction annealers, yet its power
consumption is up to three times smaller
for the same output.
The required power connection is
therefore also three times smaller when
compared to induction or conventional
furnace. This alone could represent a
considerable cost saving in terms of
peak power consumption and cabling
installation.
Efficient energy coupling also allows
accurate heat input and more uniform
recrystallisation, which is reflected
in homogeneous grain size in the
longitudinal and transversal direction.
The new annealer combines the
advantages of high speed bright
annealing and scratch-free surface
finish. Processed material does not
touch the plasma chamber when hot,
which reduces the risk of surface
scratching. This
is different to the
conventional strand
furnace where
tubes remain in
contact with the
furnace guiding
supports during the
maximum elevated
temperatures, when they are most
vulnerable to surface damage.
A feature of plasma annealing is that
heating is conducted in low-pressure
inert atmosphere, for which a vacuum
installation and accurate material
guiding is necessary. The advantage
of a vacuum system is that purging gas
(usually hydrogen) is supplied at low
pressure, which reduces overall purging
gas consumption.
The new facility occupies about
one third of the shop-floor area that
is required by a conventional multi-
line annealing furnace of the same
capacity. A single plasma line can
substitute around ten traditional lines
on a conventional strand furnace,
which reduces the investment required
for transport systems, take-ups and
payoffs.
Plasmait GmbH – Austria
Fax: +43 3182 52 4754
Email:
Website:
Plasmait’s HPA60
plasma annealer