WCA January 2015

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58 Wire & Cable ASIA – January/February 2015
Developments in green
technologies for power
cables – using clean
materials in the
production process
By Sikora AG
Introduction
Green technology is a topic which plays an increasingly
important role worldwide, especially in light of greater
shortages of resources and increasing environmental
pollution. Industry has an obligation to develop products
and processes that are sustainable, energy saving and
environmentally compatible. At the same time, these
products and processes have to be highly profitable.
Crude oil is a basic irreplaceable resource. Oil is used in
the form of plastic materials for cable insulation. Sikora’s
understanding is to provide technical solutions for online
quality assurance of materials and cables to enable
economic and ecological production processes. By
integrating measuring and control as well as inspection
and sorting technologies in the production line, the scrap
rate can be reduced and consequently material saved.
Every litre of oil that can be saved due to lower rejection
rates and less material consumption also conserves the
less available resource.
This article introduces a novel technological solution that
inspects the purity of XLPE pellets that are used at the
insulation process of power cables. It is the first system
on the market that inspects pellets to 100 per cent and
automatically sorts out contaminated pellets before they
get into the extrusion process. By assuring absolute clean
insulation material, the system supports the requirements
of green technology within the process chain. The tech-
nology is the result of a development cooperation between
Sikora and Maillefer.
Necessity of clean XLPE compound
for power cables
The purity of the XLPE compound that is used for the
insulation of power cables plays a critical role. Perfectly
pure compound reduces the risk of a breakdown.
Metallic impurities of 50μm may cause damage to the end
product with high follow up costs that can easily run into
the millions.
The repair of a defective submarine cable, for example,
which has been damaged by contamination, can lead to
weeks of downtime.
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❍ Metallic contamination inside the pellet (X-ray)
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❍ “Black specs” on the pellet (big and small) (Optical)