Rieter

Roving twist level

Index

Because of longer fibres and higher fibre-fibre friction, the twist level in man-made fibre roving has to be set lower than the twist level for cotton. Too high levels result in drafting difficulties in the ring spinning process, which are reinforced by high air-moisture levels because of the higher mutual adherence of the fibres. Certainly, the twist level still has to be high enough to avoid false drafts in the roving and ring spinning process.

In general, it can be said that the twist level must be higher with:

  • coarser fibres
  • shorter fibres
  • finer roving fineness.

Recommendations for the twist level of man-made fibre roving according to the fineness of the roving and to the fineness of the fibres can be seen in Fig. 42. For blended yarns the twist level should be set between those for cotton and those for synthetics in correspondence with the blend proportions.

Fig. 42 – Roving twist level recommendations