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Feature
Steel wire,
cable & rod
T
he needle-makers credited with the development of steel wire were custom craftsmen
by the standards of any period. They worked for a select group of clients – themselves.
They perfected a single elegant mechanism – the aperture. They preserved the integrity of
their art by reposing their secrets in a guild.
The steel wire makers of today have a more complicated time of it. Even in the brief interlude between
rolling and drawing they must cope with a pair of colour-coded menaces: the magnetite (Fe
3
O
4
) blue
oxide that forms on the wire as it cools following the rolling process; and the maghemite (Fe
2
O
3
)
red surface oxide, or rust, that forms during shipping and storage. Decisions have to be made as to
the best scale-removal method. Is it to be acid pickling? If so, which kind: chemical – or electrolytic?
Perhaps mechanical descaling is preferable. Or abrasive blasting or sanding. Or shaving.
The latter-day artisan will already have confronted the challenges presented by the wire rod.
Any miscalculation or variation as to temperature or ferrous content – during pouring, rolling, or
treatment – will likely present as a defect which, magnified throughout the production process, means
major trouble with the drawing dies. The check-list may be very much longer. But the ideal served in a
modern steel wire making plant is traditional, and simply stated: that the product be perfect of kind.
The suppliers reviewed in this section of EuroWire are able partners in the enterprise.
EuroWire – September 2009
Photo courtesy of C M Caballé SA
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