# Rieter

### Deterioration in evenness during processing

#### Index

In processing in the spinning mill, the unevenness of the product increases from stage to stage after the drawframe. There are two reasons for this:

• The number of fibers in the section steadily decreases. Uniform arrangement of the fibers becomes more difficult, the smaller their number.
• Each drafting operation increases the unevenness.

The contribution made by any one machine to the overall deterioration in evenness can be calculated. If, for example, a ring-spun yarn produced from a roving with a CV value of 4% has an unevenness of CV = 13.6%, then the contribution of the ring spinning machine is:

${CV}^2_{actual} = {CV}^2_{feed} +{CV}^2_{additional}$

for our example:

$CV_{additional} = \sqrt{{13,6}^2 -{4}^2} = 13 \%$