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ALUMINIUM SMELTING INDUSTRY
Gautschi Engineering – An industry profile
O. Moos, Gautschi Engineering
Gautschi Engineering GmbH is one of
the world’s leading suppliers of casthouse
and heat treatment technology for the
aluminium industry since 1922. The wide
product range includes all necessary control
and automation equipment, and its
reliability and efficiency has been a major
contribution to the success of the company
over all those years. Gautschi has been
a supplier to all the
large aluminium
producers as well
as to many smaller,
independent companies
around the
world.
From the start, the
company has worked
to gain a thorough understanding
of its customers’
needs so that
together with them it
can develop comprehensive
solutions to
meet all their requirements.
This naturally
applied especially to
the beginning of its
operation, when the
commercial production
of aluminium had
just been established.
Gautschi’s head office
location in Switzerland certainly contributed
to the success in the aluminium industry, as
the first commercially operated smelter was
located just a few kilometres away. In addition,
the first aluminium cold rolling mill was
established in a neighbouring town.
As most components required to operate
the equipment were then not easily available,
Gautschi invested heavily in developing its
own technologies. In the early times, even
fuel and air line components were fabricated
in-house. For a period of time, Gautschi produced
part of the insulation material in its own
factory. Hydraulic equipment from valves to
cylinders was supplied by Gautschi. In addition,
the control systems are designed and
programmed in-house up to this day. Furthermore,
we still use our own design for blowers,
fans and burners (cold air, hot air and regenerative).
Nowadays, most components for combustion,
hydraulic, pneumatic and electric systems
are sourced from leading suppliers. However,
the profound experience from the past allows
Gautschi to understand basic principles
when designing the equipment supplied, and
to judge what components are most suitable
for a specific application.
Its history and wide product range allows
a system supplier such as Gautschi to offer all
Round top charged melting furnace with a melting capacity of 30 tonnes per hour
necessary expertise not only for a specific piece
of equipment, but also for its auxiliary components
and for equipment/processes adjacent
to the equipment within the whole working
area. For example, a casting machine can only
produce a certain quality if the casting process
already meets specific requirements.
Liquid metal furnaces
For many years, liquid metal furnaces for
standard applications were seen just as a necessity
in an aluminium casthouse. Main efforts
were put into the design of casting machines
(the heart of the casthouse) and the heat
treatment facilities. But in the second half of
the last century, the dramatic increase in energy
cost together with stringent environmental
requirements, and the demand for top quality
products, drove furnace suppliers and users
to take a new look at their furnaces. Nowadays
you can choose from numerous designs for liquid
metal furnaces according to the differing
requirements of modern casthouses.
Gautschi supplies a wide range of different
liquid metal furnaces with capacities between
10 to 140+ tonnes. Melting rates above 40 t/h
have been achieved in remelt facilities.
As mentioned above, Gautschi started to
develop its own technologies early on. This
was on the one
hand because certain
technologies
were not available
on the market, and
on the other hand,
because the available
technologies are
not always suitable
for specific applications.
Over the many
decades in operation,
the company developed
a wide range
of burners with a capacity
between 500
to 9,500 kW. These
burners either work
with cold air, or
with hot air (using a
central recuperator)
or they are regenerative,
with a heat
© Gautschi Engineering
exchanger module
directly attached to the burner head. In addition,
the burners can operate with different
fuels according to the customer’s needs.
Gautschi is especially proud having a regenerative
combustion system at hand (the Varega
Regenerative Combustion System), bringing
the thermal energy consumption down to
rates as low as 465 kWh th /t Al . Naturally, this
depends on a lot of factors, starting with good
house keeping practices (what kind of charging
material is available and how is separated and
stored), and including the kind of furnace used
as well as the level of maintenance done on
the equipment. In addition to being the most
efficient combustion system on the market,
the Gautschi Varega Regenerative Combustion
System requires minimal maintenance.
Other systems on the market require costly
maintenance at intervals of a few weeks to a
couple of months. For example, the ceramic
balls in the regenerator must be removed and
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