Annealer for
Flat Stainless Steel
Wires and Profiles
Plasmait GmbH from Austria is seeing an
increasing demand for its high-output
plasma heat treatment lines for stainless
steel products especially in Asia. For example
Plasmait deployed a 30kW plasma annealer
to a renowned stainless steel wire producer in
South East Asia, who used plasma to replace
its traditional tube furnace for production of
flat ferritic and austenitic product with widths
up to 30mm. The HPA30 plasma annealer
with output capacity of 100kg per hour will
allow the manufacturer to half the energy
cost per kilogram of output whilst allowing
for a considerable cost saving in terms of
peak power consumption. Much lower power
connection requirements of plasma annealer
means also cheaper cabling installation for
connecting power.
The new annealer combines the advantages high
speed bright annealing and superior scratch-free
surface finish. Processed material does not touch
plasma chamber when at high temperature 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 also during the maximum elevated
temperatures when they are most vulnerable to
the surface damage.
A unique 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 vacuum system is that purging gas
(usually hydrogen or forming gas) is supplied at
low pressure, which reduces overall purging gas
consumption.
The new compact single-line production will have
the same output as the old multiline furnace and
will take just about one third of shop floor space.
A single-line production will also reduce material
manipulation and limit the investment into the
associated takeups, payoffs and transport system.
A typical plasma annealer installation
for stainless steel applications can
substitute around 10 traditional lines
on a conventional strand furnace.
Igor Rogelj, Commercial Director
Tel (Austria)+43-3182-52-475-0
Plasmait GmbH,
[email protected]
www.plasmait.com
Plasma annealer allows accurate
heat input and hence more uniform
recrystallization, which is reflected
in homogenous grain size in the
longitudinal and transversal direction.
The HPA30 annealer features also an
extended tempering zone to allow for
extended dwell time or slow cooling,
which is necessary for selected ferritic
grades of stainless steel.
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WN JULY 2017