Roving Frame Drafting and Twist Insertion
topic
Roving frames draft sliver from approximately Ne 0.1 to roving counts of Ne 0.5 to 2.0 through 3-over-3 drafting systems with apron guidance in the main drafting zone, inserting 0.5 to 2.0 turns per centimetre of protective twist through a flyer rotating at 800 to 1200 rpm before winding the twisted roving onto a bobbin through a differential builder mechanism that maintains uniform winding tension.
Role
Produces the lightly twisted roving that bridges the count gap between drawn sliver and the ring frame feed requirement, with roving twist per unit length being the critical parameter governing roving strength adequate for creel handling without excessive twist that would resist drafting on the ring frame and cause yarn count variation and spinning ends down.