First steps to consistent quality

The new USTER® CLASSIMAT 5 uses advanced sensor technology to detect potentially damaging outliers

The new USTER® CLASSIMAT 5 is a ground-breaking innovation, expanding the scope of the well-known CLASSIMAT® instrument beyond traditional classification – and identifying both foreign matter and polypropylene defects. As part of an integrated testing and monitoring regime from laboratory to finished package, it provides the essential framework for the production of consistent quality in spun yarns.

With latest-technology sensors and class-leading software, the new CLASSIMAT® can both measure and quantify a wider range of defects than ever before. It introduces automatic identification of disturbing defects – known as outliers – for all fault types. This feature helps spinners understand how to eradicate these defects using yarn clearing, so they can deliver the quality their customers require.

Taking quality assurance further, USTER® CLASSIMAT 5 also provides objective assessment of quality consistency, based on testing and quantifying outliers in a large sample size of 200 kilometers.

New and unique
The YARN BODY concept is now acknowledged to be the best approach for identifying disturbing defects. It was introduced with the USTER® QUANTUM 3 yarn clearer and has proved its reliability on extensive yarn varieties. USTER® CLASSIMAT 5 shows the YARN BODY alongside a numeric classification of thick and thin places. The degree of contamination is also profiled, showing up graphically as a dense area for colored foreign matter and vegetable matter, as well as numerically. For the first time, polypropylene defects are classified as either short or long.

USTER® CLASSIMAT 5 featuring the yarn body concept

Previous CLASSIMAT® generations used 23 different classes, giving good coverage of all detected faults. However, there has been enormous progress in yarn quality – yarns have become more even, with the result that smaller defects are now viewed as disturbing. These small faults can now be detected and classified by the USTER® CLASSIMAT 5, extending the existing classification table to include a total of 45 classes.

To support previous classification standards – well-established in yarn trading – and allow a gradual transition to the latest level, USTER® CLASSIMAT 5 also converts test values for thick and thin places to match earlier USTER® CLASSIMAT 3 and USTER® CLASSIMAT QUANTUM classes.

Outlier classification – a new standard
Even a few substandard bobbins can damage fabric appearance and seriously impact on productivity in downstream processes. Experience shows that poor quality in only a small percentage of a yarn lot can often cause an entire delivery to be rejected by the customer. These bobbins, containing defects outside the normal distribution in any fault category, are termed outliers. For the first time, they can be measured and quantified in the laboratory by USTER® CLASSIMAT 5. The outliers can then be effectively controlled using yarn clearing to remove them at the winding stage, using data from USTER® CLASSIMAT 5 to optimize clearer settings.

The ultimate goal of preventing these defects by pinpointing the root causes in the spinning process is critical to ensure consistent quality. And the first step here is to measure and quantify them with USTER® CLASSIMAT 5. “With a proper assessment of outliers using USTER® CLASSIMAT 5, and tools to eliminate them, spinners have a practical and sustainable method to ensure and verify quality consistency”, says Uster Technologies Product Manager Sivakumar Narayanan.