The Comparison, Measuring & Labelling of Energy-efficient Textile Machinery
In the case of the belt ovens, the
energy loss through the surface also
tends to be minimized by an insulating
layer and specific design measures to
reduce thermal bridges.“High-qualityfibre
composites improve the
thermal stabilization of the
warp knitting elements and
reduce energy costs for air
conditioning to a
considerable extent.”Heat recovery
As already stated above in the
example of the drying process,
integrated air/air heat exchangers in the
ducting reduce the energy loss caused
by the exhaust air. In this way the heat
is intelligently used to heat the fresh
air for the drying process. As a result,
a heat recovery efficiency of about 30
% is usually reached. Air/water heat
exchangers are recommended (also
because they have a better heat
transfer and the associated benefits)
if there is a hot water demand in the
manufacturing environment.
Compared to a drying process, the
exhaust air volumes which are
available for heat recovery are
significantly lower but they often have
a much higher temperature. Both drying
and setting processes are suitable for
heat recovery. A payback analysis on
a case by case basis must be
undertaken using the volume of air flow
and the exhaust air temperature.
Main influencing factors
for the energy efficiency
and the resulting complexity
A textile machine is a link in a very
long production chain from the fibre to
the finished usable fabric. The
opportunities to pass through the textile
process chain to come to a similar end
product, are very numerous. Thus, the
choice of raw material, for example,
can strongly affect the process chain
with regard to energy. Furthermore, the
quality characteristics of intermediate
products such as yarn or fabric are
energy relevant.
The mechanical engineering and
technological design of the chain of
textile machinery also has a major
influence on the energy efficiency of
the process. The components used in
textile machinery, such as driveMatthias Arnold,
Vice President
Research and Development,
Karl Mayer
Textil-maschinenfabrik GmbH,
Warp Knitting Business Unit
technology, have a smaller – but not
negligible – impact on energy
efficiency. (Figure 5)
To obtain a sense of how complex it is
to assess energy efficiency throughout
the entire production process of a
textile product, the influencing
parameters and their effects are
explained using examples along the
process chain.
Influencing parameters common to
all process steps
There are parameters that affect the
energy efficiency of all process steps
throughout the entire process chain.Climate
example: climate strongly influences
the workability of the fibre during
spinning. Good workability of fibres
leads to higher productivity and thus
energy-efficient processes. climate
also affects energy flow in the heating
processes in the finishing of fabrics.
Raw material/materialComponents
Example : during carding and spinning,
polyester fibres require more energy
than cotton. even in subsequent
processes, such as in dyeing and
drying, the energy consumption in the
case of polyester is often higher. On
the other hand, the selection of the raw
material quality when buying cotton has
an effect on the specific energy
consumption.Machine components are replaceable
parts with technological effects that
are subject to wear or maintenance.
The maintenance status or degree of
wear influences energy efficiency.
examples: card clothings, spinning
components, bearings, seals. cheap
copies or no-name components which
degrade the energy balance are often
used.
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