A card feeds opened fiber onto a large main cylinder, where worker and stripper rolls covered with fine wire teeth tease the fibers into individual strands, and a doffer lifts them off as a thin web. Carded webs have strong machine-direction orientation, often 5:1 or more in strength, unless randomizing rolls or cross-lapping are used. Card speed, web weight and evenness depend heavily on fiber crimp, finish and length.
Card three is running a 25 gram web at 250 meters a minute and it's starting to look cloudy.
Card settings are gauged in thousandths of an inch between wire surfaces, and a gauge that drifts after a grind shows up as neps and weight swings.
Also heard as
- card
Related terms
Staple fiber
Fibers cut to a fixed, finite length, as opposed to continuous filament, used in carded, airlaid and wetlaid webs.
Crimp
The waviness built into staple fibers so they cling together during opening and carding.
Cross-lapper
Machine that lays a light card web back and forth across a slower conveyor to build a wider, heavier batt.
Nep
Small, tight knot of tangled fibers that shows as a speck or pimple on the fabric surface.
Loading
Buildup of fiber and finish residue in card clothing, which clogs the teeth and spoils the web.