WCA July 2013

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50 Wire & Cable ASIA – July/August 2013
Electroplating
made easy
Electroplating is the process of using
electrical current to coat an electri-
cally conductive object, in the case of
Sirio Wire, steel wire, with a relatively
thin layer of metal.
The primary application of electro-
plating deposits a layer of a metal having
some desired property, in particular, in
corrosion protection or lubricity on the
steel wire surface.
The wire works as cathode in a
conductive solution. The anode can
be the metal to be deposited itself
or insoluble anodes usually made of
activated titanium. A rectifier supplies
a direct current to the cathode causing
the metal ions in the solution to lose
their charge and plate out on the wire.
As the electrical current flows through
the circuit, the anode slowly dissolves
and replenishes the ions in the bath
or, in the case of insoluble anodes, the
metal to be plated must be periodically
replenished in the bath itself or in a
separate dissolution tank as they are
drawn out of the solution.
Sirio Wire electroplating lines have the
following features:
• Lines are composed of a set of
polypropylene working basins and a
set of tanks, made of polypropylene
welded plates
• Collecting pipes feed the working
basins; the bath is pumped from
the storage tank located below by
vertical pumps
• Preferably using insoluble anodes
and a separate dissolution tank
• Covers with counterweight systems
and aspiration caps are ideal for
containment of fumes
• PLC-based control system with
touch screen panel for control of
the elements of the line and for the
automatic calculation and supply of
intensity for the coating thickness
in function of the speed and wire
diameter
• Before entering the plating section,
the wire needs to be perfectly clean,
free of any soap residuals and
oxide coming from the previous
drawing and heat treatment
process in order to have a perfect
adhesion of the metal on the steel.
In particular, Sirio Wire supplies very
efficient electrolytic H2SO4 pickling
baths.
Sirio Wire Srl – Italy
Website:
Four types
of furnace
Wuxi Xinrun Industrial Furnaces offer four types
of gas open fire heating furnaces for annealing
steel wire. The main features of the furnaces
include high heating efficiency, patented pre-
mixed combustion technology, high speed
convection burners, branded main control
components, and user-friendly and safe function
designed to facilitate on-site operation and
maintenance.
The whole furnace is of counter-flow open
fire type. The furnace body is combined in several
sections. Each heating section is relatively
independent, but also affects the others.
The furnace temperature and heating atmosphere
can be set according to the requirements of heat
treatment process, and re-oxidation of wires can
be efficiently avoided.
The temperature and heating atmosphere of each section
of the furnace can be controlled independently, using the
technology of pre-mixed gas heating. The gas and air will be
pre-mixed to the required ratio by the mixer before going into
the nozzle for burning. The high-speed heated atmosphere
ejecting into the furnace cavity would produce gaseous
circulation.
The structure is designed so that the temperature of
the heating section will keep stable and without partial
overheating. As the burning is inside the nozzles, there is no
visible fire inside the furnace cavity.
The de-carbonisation and oxidation of wires can effectively
be avoided when the temperature and heating atmosphere
are set according to the technical process requirements.
The supply of gas is controlled by a pressure relief valve,
safety shut-off valve and diffusion valve. This system will only
work when the pressure of air and gas is stable. Only when
the pressure of air/gas and the electricity supply are all stable
will the gas supply be used.
Wuxi Xinrun Industrial Furnace Co Ltd – China
Website:
❍
❍ Counter-flow open type furnace from Wuxi Xinrun
❍
❍ Electro-galvanising line from Sirio Wire