EoW January 2009

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EuroWire – January 2009 47
wire drawing machines
“Two proven techniques, aluminium rod rolling from
Continuus-Properzi and steel rod drawing from OTT’s
wire machinery division, are united to bring synergy to
the process of dry drawing,” explains Mr R Contini, sales
director of the wire machinery division.
AS wire is produced by initially extruding aluminium rod
on a steel wire, and then reducing to the final size by
drawing. The drawing technique, known as dry drawing
by pressure dies, is designed to avoid stripping the
aluminium from the steel core during the operation.
The wire passing through special dies and bushings,
which guarantee the required lubrication, generates the
pressure needed to facilitate the drawing process.
The drawing of AS wire has undergone years of research
and development aimed to improve major process
variables in order to boost quality and productivity while
reducing operational costs.
The main requirements of the AS wire drawing process are
best met with a non-slip type drawing line that provides
efficient cooling of the blocks and dies, possesses the
most appropriate block profile, accurately synchronises
the blocks and facilitates easy alignment of the die
holders.
The high performance of the capstan and die cooling
technology, the lack of wire path deviation, improved back
tension control, a lack of wire torsion, and the use of the
most modern inverters and AC motors combine to maximise product quality while optimising machine performance. The drawing
line is composed of a drawing machine with vertical axis blocks of 670mm, a motorised pay off for single bobbin up to 1,800mm,
a cleaning unit, and a take up for single bobbin up to 1,250mm.
The number of blocks of the drawing machine depends on the desired reduction as well as the required final tensile strength of the
wire. The most common machine is composed of eight blocks, although machines with ten blocks have been supplied where there is
a requirement for different wire diameters and tensile strengths, or to provide flexibility.
The drawing machine is also equipped with completely sealed safety guards, internal lamps and an exhaust system to evacuate the
dust generated during the drawing process.
Continuus-Properzi SpA – Italy
Fax: +39 0298 10358 Email: Website:
Model TMD 8D670 drawing machine ❍ ❍
Dry drawing AS wire
Performance of the drawing line ❍ ❍
1) Material: AS WIRE ‘20SA’ Number of blocks: 8
Wire diameter Inlet: 7.35mm Outlet: 3.45mm
Tensile Outlet: 1400 N/mm2
Speed 3.8 m/s
2) Material: AS WIRE ‘20SA’ Number of blocks: 8
Wire diameter Inlet: 6.3mm Outlet: 2.89mm
Tensile Outlet: 1400 N/mm2
Speed 5.4 m/s
3) Material: AS WIRE ‘20SA’ Number of blocks: 8
Wire diameter Inlet: 4.4mm Outlet: 2.05mm
Tensile Outlet: 1400 N/mm2
Speed 7.2 m/s
4) Material: AS WIRE ‘20SA’ Number of blocks: 10
Wire diameter Inlet: 7mm Outlet: 2.2mm
Tensile Outlet: 1400 N/mm2
Speed 7.5 m/s
5) Material: AS WIRE ‘27SA’ Number of blocks: 8
Wire diameter Inlet: 6mm Outlet: 2.2mm
Tensile Outlet: 1060 N/mm2
Speed 4.5 m/s
6) Material: AS WIRE ‘40SA’ Number of blocks: 6
Wire diameter Inlet: 6.65mm Outlet: 3.5mm
Tensile Outlet: 680 N/mm2
Speed 3.5 m/s