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PROVEN
PERFORMANCE
Cablegard has been independently tested and approved by a number
of leading electricity suppliers and major conductor manufacturers.
Even more important is Cablegard's proven performance in actual usage
on conductors installed around various parts of the world. It has been
shown to give much greater protection from corrosion than the more traditionally
used hot-applied greases. In fact, not a single instance of failure
has been reported in over two decades.
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Most overhead power cables/conductors consist of aluminium strands,
sometimes reinforced by central strands of galvanised steel - Aluminium
Conductor Steel Reinforced (ACSRs).
Although aluminium is generally considered to be fairly corrosion
resistant, it is prone to crevice corrosion. A stranded conductor
inevitably presents many crevices, as each strand is in contact
with its neighbours. Importantly, the zinc of the reinforcing strands
of ACSRs is also prone to crevice corrosion.
The most corrosive atmospheres are generally encountered in salt-laden
coastal regions and in industrial areas with their atmospheric pollutants
such as sulphur dioxide. Given that much of the world's population
and its accompanying industry is concentrated in coastal regions,
both salt and acid pollutants are frequently found together. Clearly
the life of a conductor is determined by the degree to which it
can withstand this corrosive cocktail.
The traditional method of combatting corrosion has involved the application
of molten grease during the manufacture of the conductor. This entails
maintaining a fairly large thermally insulated reservoir of permanently
molten grease and pumping it into the point(s) of application. The
process is somewhat hit-or-miss and generally fails to completely
fill the crevices between conductor strands. In fact, specifications
call for only a 65% minimum of the theoretical fill - leaving as
much as 35% of the length of the conductor unprotected. A
chain is only as strong as its weakest link!
At least as important as filling the conductor is that the grease
should be an effective corrosion protective for aluminium, zinc
and steel, both individually and also in mutual contact, to prevent
galvanic corrosion. In tests - and in practice - most widely used
hot applied greases fail to come up to the highest standards in
this respect.
Cablegard
is the easily applied anticorrosive that reaches where others cannot
and performs where others fail. By this means it extends conductor
life, thereby offering the world's power generators and distributors
major cost savings.
UNIQUE
PATENTED FORMULATION
Cablegard consists of
a synergistic blend of corrosion inhibitors, penetrating aids, metals
deactivators and age resistors in a highly refined, gelled mineral
oil. It protects all major metals and alloys and is especially effective
on steel, aluminium and zinc.
COLD
APPLIED
Cablegard is applied during manufacture of the conductor at room
temperature - straight from the drum as received. The need for
the melting, storing, pumping and application of a molten grease is
entirely eliminated. Cold application makes for a much cleaner operation
than that of a molten grease where strict temperature control - and
therefore viscosity - is very hard to achieve, making the operation
both messy and difficult to control.
STAYS IN PLACE
Cablegard is fluid at room temperature during pumping and application.
However, once it has been applied to the conductor it immediately
re-gels and stiffens to a grease-like consistency (it is highly pseudoplastic)
to remain firmly in place.
FILLS THE CONDUCTOR COMPLETELY
Unlike hot-applied greases, Cablegard's unique viscosity and flow
characteristics enable the entire conductor to be 100% filled to ensure
complete protection. In this way, the crevice corrosion, which is
the main cause of failure, is eliminated.
WILL
NOT MELT OR DRAIN AWAY
Cablegard's unique gelling, or thickening, system imparts excellent
high temperature properties to the product. It will not melt, even
at temperatures as high as 200șC. In short, it stays where it is put,
regardless of the highest temperatures likely to be encountered.
SHORT
TERM
Naturally, the cost of the high performance Cablegard
anticorrosive is initially a little more than that of the relatively
crude hot-applied greases. However, this is largely offset by the savings
due to:
- Ease
of application
- Elimination
of heating and capital costs associated with storing and pumping
molten grease
- No
trace-heated pipework to install and maintain
- Cleaner,
less messy operation
- Improved
safety compared to the handling of hot molten grease.
LONG
TERM - "THE BOTTOM LINE"
The greatly superior protective properties of Cablegard, together with
the complete fill of the conductor, will considerably extend the useful
life of conductors. This, allied with reduced maintenance, offers long-term
savings many orders of magnitude greater than the (relatively tiny)
extra cost of the Cablegard which is infinitesimal when overall costs
are taken into account:
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The
cost of conductors themselves
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And,
greatest cost of all...replacement of corroded conductors.
For
further information, please contact Dr Alan Parkinson or Mr Colin Jones
at Vapor-Tek Limited.
Telephone +44 (0)1204 521795.
Please request a brochure/technical details by using our on-line enquiry
form
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