Dept. of Textile Technology
Sarvajanik College Of Engg. & Technology
Affiliated by Veer Narmad South Gujarat
University, Surat (Gujarat).
ABSTRACT
|
|
Since drafting at Ring Frame
is a major influence on yarn qualities & ultimately tells on even fabric
appearance, conversion of drafting to upgrade ring frame is a worthwhile
exercise. Casablanca drafting represents the first development to improve the
control over floating fibres. Drawbacks of this drafting lead to Top Arm
drafting thereby preventing slippage of back top roller. Though similar but
with further development to ensure provision for varying pressure on top
rollers came Second generation Top Arm drafting. Then aroused the need for
making changes in top rollers & cots, & now detachable types of top
roller with softer cot on front roller are available. Offset drafting &
Compact drafting represents the latest development in drafting system at Ring
Frame.
|
INTRODUCTION
Since drafting at Ring Frame is a
major influence on yarn qualities & ultimately tells on even fabric
appearance, conversion of drafting to upgrade ring frame is a worthwhile
exercise.
Among the various components of
ring frame, drafting has the maximum influence on yarn quality &ring
performance. Drafting at Ring Frame considerably influences not only evenness
and appearance of yarn, but also performance of yarn, appearance of fabric, and
rejections due to yarn faults. Therefore conversion of drafting is given a high
priority in the efforts to upgrade a Ring Frame and the payback from such
investments is attractive.
IRREGULARITY IN DRAFTING
Irregularity added in drafting is
mainly caused by:
1. Inadequate control over
the movement of short and floating fibres.
2. Slippage of strand and
fibres under the drafting roller.
3. Variations in speed of
drafting rollers.
4. Mechanical faults.
Developments in drafting have therefore
focused mainly on reducing the contribution from these factors.