Winding Tension, Bobbin Formation, Speed and Production

Winding Tension

If winding tension is selected properly, the following tensile properties are not affected
  • Tenacity
  • Elongation
  • Work- to- break
But excessive tension in winding will deteriarate the above said tensile properties.

Characterestics Of Bobbin Formation

Stretch Length

It is the length of the yarn deposited on the bobbin tube during each chase (one up and down movement of ringrail ) of ring rail. The length should be around 3.5 to 5 meters. It should be shorter for coarser yarns and longer for fine yarns.

Winding Ratio

It is the ratio of the length of yarn wound during the upward movement of the ring rail and the length wound during the downward movement of the ringrail.

Bobbin Taper

The ratio of the length of the upper taper of the cop (bobbin with yarn) to the diameter of the bobbin must be 1:2 or greater. 
 

Winding Speed

It depends upon the following factors
  • Count
  • Type of Yarn, (type of fibre, average strength and minimum strength)
  • Type and Charactersitics of Bobbin
  • Package Taper
  • Final Use of Package
The best winding speed is the speed which allows the highest level of production possible for a given type of yarn and type of package, and with no damage whatsoever to the yarn.(abrasion and breaks due to excessive tension)

Winding Production

It depends upon the following factors
  • Winding speed
  • Time required by the machine to carry out one splicing operation
  • Bobbin length per bobbin( both bobbin weight and tpi to be considered, because TPI will affect the bobbin length). This decides the number of bobbin changes
  • The number of faults in the yarn and the clearer settings, this decides the clearer cuts
  • Count
  • The number of doffs. It depends upon the doff weight. Higher the doff weight, lower the number of doffs
  • The time taken for each doff either by the doffer or by an operator
  • Down time due to red light. It depends upon, number of red lights, number of repeaters setting for red lights, clearer settings like off count channel, cluster setting which will result in red lights and others
  • Bobbin rejections, it depends on weak yarn, wrong gaiting, double gaiting, bobbin characteritics etc.