Roller setting and drafting in the roving frame:
Table of Contents
Roller setting in the roving frame:
Roller setting is the process of positioning the machine’s rollers depending on the fiber length and the distance between the centers of the pair of rollers. The roller setting of the drafting zone in any machine usually depends on the staple length or effective length of the fiber being processed by that machine. https://bdfabric.com/description-and-working-principles-of-simplex-machine/
Types of Rollers Used in roving frames:
Two types of rollers are generally used in the drafting zone of the roving frame.
1. Top roller.
2. Bottom roller.
The upper part of the top roller is coated with rubber, called Cot. The surface of the top roller contracts and rotates.
Bottom rollers are of the following types.
1. Straight fluted.
2. Diagonal fluted.
3. Diamond fluted.
Diagonal fluted rollers are more commonly used nowadays.
Factors that influence roller setting of roving frame:
The roller setting of the roving frame depends on the following factors:
1. Effective length of fiber or staple length.
2. The weight of the previous product ie the thickness of the sliver.
3. On the hardness of the feeding material.
4. On the amount of the draft.
5. On the speed of the machine.
6. On the type of roller.
7. On fiber quality.
8. On the number of small fibers present in the fiber.
Drafting in the roving frame:
Roller setting and drafting in the roving frame. In the spinning line, the fibers are first made into laps, then into sliver roving, and finally into yarn. The elongation of fiber bundles by different methods is called drafting.
Roller setting in the drafting zone:
The distance between the gripping points of any 2 pairs of rollers is called the setting of the rollers. The roller setting of the drafting zone in any machine is usually set depending on the staple length or effective length of the fibers being processed in that machine. If the setting distance is long, various problems are caused in fiber processing, similarly, if the setting distance is too short, problems are caused.
The following points should be given importance for roller setting:
1. Additional allowance should be made in a rear zone as compared to a front zone.
2. The thicker the roving, the greater the allowance.
3. If the feeding weight i.e. fiber content is more, the setting will be more comprehensive.