Short staple spinning
Groz-Beckert supplies high quality card clothing for different types of cards and areas of application. The selection encompasses metallic card clothing for feed roller, licker-in, cylinder, doffer and stripping rollers. The product range is complemented by revolving tops, stationary flats and cleaning fillets.
Feed roller wires
This wire is responsible for uniform feeding of fibers into the card. Coarse wire is usually used to control thick fiber mats.
The Licker-in's task is to open the fiber tufts, clean and prepare them for the carding process.
Together with the revolving flats and stationary flats in the pre and post carding zones, the cylinder is responsible for main carding action, fiber separation and removal of short fibers and trashes.
The doffer wire takes over the fibers from the cylinder. A high rate of fiber transfer should be reached in addition to uniform web transfer.
Stripping roller wires
The stripping wire strips the web from the doffer wire. Web transfer should be gentle without forming additional variations in slivers. Only then uniform yarn can be produced in the spinning process.
Revolving tops consists of flexible wires which, along with the cylinder, take on the main carding action. In addition to carding, tops are designed to collect trash, dust and short fibers.
Revolving tops are available in different heights and with varying PPSI, selected in accordance with production level and spinning process.
Tops with high PPSI are recommended for fine ring-spun yarn; tops with low PPSI are primarily used for coarse ring-spun yarn and open-end yarn.
Stationary flats in the pre and post carding zone, along with the revolving tops, provide for additional carding.
In the pre carding zone the raw material should be prepared in such a way that the load on the flats is limited. Large fiber tufts are opened into smaller fiber tufts by the stationary flats.
In the post carding zone further carding takes place in which the fibers are again parallelized and individualized.
If cotton is being processed then the fiber of the stationary flats in the pre and post carding zone must be prepared in such a way that trash and dust can be removed by the mote knives.
Cleaning fillets are used for cleaning rollers for stripping rollers and for revolving tops.
The cleaning roller of the stripping roller prevents lapping of the stripping roller, while cleaning rollers for revolving tops remove the flat strips from the revolving tops. For good carding results and for keeping the card sliver clean, flat strips must be completely removed.
Raw materials arrive at spinning mills in compressed bales. They are opened and cleaned in the blowroom, which subjects the material to high stress.
The high speeds of the beater rollers can create neps which diminish yarn quality and therefore must be removed by the carding process.
Yet high beater speeds are beneficial to intensive cleaning of the cotton and require a compromise between cleaning efficiency and nep generation in order to achieve good results. It is thus linked to some fundamental considerations:
- The wires used must be adapted to the process sequence. The cleaning and opening positions in the blowroom should become finer.
- The front angle of the wire is crucial to cleaning efficiency. A larger angle implies more aggressive opening of fibers and hence more intensive cleaning. The use of less aggressive clothing is recommended for finer fibers.
- Wear on the wire lowers the intensity of the cleaning and opening process of the raw material. For consistent quality it is therefore important not to use worn wires.
Border wires are necessary to securely fasten the beginning and the end of card wires onto a roller and are embedded in the grooves at the edge of the rollers.
Border wires are removed and replaced when ever grinding of a roller is necessary.
Groz-Beckert also offers special accessories for cleaning, assessment and adjustment work.
The products range from setting and flat gauges, deburring and grinding stones to hand cards and brass brushes.