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bobbins. The other clearing channel focuses on different reference lengths run parallel. This is
full-length monitoring of the bobbins and cuts helpful in defining the clearing limits for mélange
defects where shade variations are identified. yarns, which obviously contain more subtle
Mélange yarns Settings for this function can be input easily by Some customers have asked why such an excellent
variations in shade than single-colored yarns.
defining a clearing limit. The Shade Variation
feature is then activated as soon as the yarn is
feature was not available with previous generations
running, checking the color of the bobbin, to
ensure no mix-up has occurred. The initial Shade of yarn clearers. The answer is both simple and
important: Only the combination of the green and
Variation (SV) limit is set closer than the red LED light in parallel makes the great sensitivity
when the slightest Continuous Shade Variation (CSV) channel of detection and separation possible – and only this
combination works as a reliable fallback system in
setting, which now takes over and verifies the
shade variation matters whole length of yarn. With the CSV function, case of an operator failure.
Barré effect caused by a wrong colored bobbin Magnified part of the defective fabric
The growing market for colored and mélange A customer has defined the spinner’s
yarns brings a challenging requirement for requirement in a simple statement: “The clearer
spinners: shade variations are simply not has to detect any mix-up of shades when the
acceptable. Mélange effects typically involve operator fails.” With this objective in mind,
many different effects and unique designs – often USTER organized trials in a Turkish spinning mill
produced in small lots. This can lead to problems to challenge the new software feature in
when bobbins of different color shades are detecting very slight color deviations.
unwittingly mixed up. It can happen all too easily,
for example when an unwary operator is feeding Two different blends were used for this
spinning bobbins to the winding machine, a evaluation, as follows:
single bobbin falls down and is not correctly Type 1: 99% white viscose 1% black viscose
identified afterwards. Type 2: 98% white viscose 2% black viscose
Now, a new software feature called Shade As seen in the picture, there was virtually no
Variation (SV) – introduced with the USTER® difference to be seen in the packages. However,
QUANTUM 3 Anniversary Edition – aims to help at the next manufacturing stage, as the yarns
customers prevent expensive fabric claims were compressed in the knitting process, the
arising from mixed-up color shades. In many slightest color shade deviation would result in a
mills, especially those using stand-alone winders, dominant but uncontrolled barré effect, easily
the risk of operator error is high. It might be that affecting 4 to 5 kilograms of knitted fabric.
light conditions in the mill make it difficult to see
color differences properly, or an operator is not For the shade variation feature, the USTER®
aware of the serious negative impact that a single QUANTUM 3 yarn clearer uses two separate
bobbin of a different color can have. In short, clearing channels focusing on color deviations. In
even a single ‘wrong’ bobbin can cause the trial, the start-up channel detected mixed-up
hundreds of dollars of damage in customer bobbins after measuring just two meters of the
quality claims. yarn, and immediately ejected the defective Yarns of two different color shades
August/September 2017 August/September 2017

