Two maxims of the experts - ‘The card is the heart of the spinning mill’ and ‘Well carded is half spun’ – demonstrate the immense significance of carding for the final result of the spinning operation. According to Dr. Artzt of the Research Institute in Denkendorf, Germany, the operation of the card shows:
- the highest correlation to quality;
- and also to productivity.
The importance of carding is even greater where new spinning systems are concerned. The considerable influence of the card on yarn quality arises from the very complex series of events in the process itself, and also from the pressure to adopt an extremely high production rate on economic grounds. This high production rate causes problems, since there is a close relationship between increases in production and reductions in quality:
- the higher the performance, the more sensitive the carding operation becomes
- and the greater the danger of a negative influence on quality.
One of several causes is that we are still operating according to a concept dating from 1770 and with a type of machine dating from 1850. On the other hand, since 1965 production rates have increased from about 5 kg/h to about 220 kg/h – a rate of increase not matched by any other textile machine except the drawframe.
When dealing with cards it has to be kept in mind that nowadays cards and blowroom form an integral, homogeneous, inseparable unit, coordinated to complement one another.
While in the case of an easy-to-clean cotton, for example, the blowroom line might assume most of the working load required, for hard-to-clean cotton this might be done by the card.