For wool worsted spinning, cards with rotating drums covered with needled clothing are used. The card has the task of cleaning, parallelizing and laying the fibres in form of a web (Fig. 9). The fibre feeding is at present completely automated.
The cards are equipped with computerized control systems which monitor each processing phase. The result of the process is entrusted to precise micrometric adjustments of the various machine members and this is the more important, the more valuable are the fibres to processed.
In these cases cards with up to 12 carding points are used, which ensure a mild and progressive opening and parallelizing action.
At the delivery from the machines, the web is taken-up in form of sliver which is made thinner by passing through a draft unit with pinned discs for a guided control of the fibres.
To increase production at same speed, the working width have been increased up to 3500 mm.
In this draft unit also autolevelling systems are installed.
