Considerable progress has been made in the area of workplace safety (owing to its structure, the card is, unfortunately, a highly dangerous machine): as a result, the carding units and the sides are now protected and fitted with safety devices. The widespread installation of automatic cleaning devices has made an important contribution to efforts to increase safety in the workplace, eliminating the need for manual intervention in this generally rather risky operation.
Technical characteristics of carding room equipment:
- working width: from 2,000 mm to 3,500 mm
- diameter of drums: from 1,500 mm to 1,650 mm
- diameter of comber rollers:1,280 mm
- number of working cylinders: up to 6 per drum
- number of cards: two or three
- number of quills: 8/12/16/20, depending on the working width and count
- number of rovings: max. 360
- production rate: max. 70 m/min, depending on the count and type of fibre
- range of yarn counts: up to 48 Nm

Settings and production

The main equipment settings concern the draft and production.

Adjustment of draft is important in order to obtain the required roving count, given that the draft imparted by the spinning machine in the woollen cycle has quite narrow limits. The mechanical draft can be calculated as follows

S = Vp / Va

in which Vp represents the speed of the comber roller and Va that of the feeders of the last machine.
Production, on the other hand, can be adjusted by increasing or reducing the speed of the comber roller in relation to that of the large drum, in other words by adjusting the condensation of the fibres for the formation of the web. The speed of the comber roller is thus limited by the evenness of the web, which must be uniform and not present thin places or tears
The divider output is expressed as:

P = Vp x T web

in which

T web = N° rovings /roving Nm

Considerable progress has been made in the area of workplace safety (owing to its structure, the card is, unfortunately, a highly dangerous machine):