Yarn Tension Yarn Tension and and Balloon Balloon Geometry in Geometry in Ring SpinningRing Spinning

• Introduction• Yarn Tension– Objectives– Tension Zones• Winding Zone• Balloon Zone –

Spinning Zone– Influence of Various

parameters on Yarn Tension

• Balloon Geometry– Physics behind– Balloon Collapse

• Modifications in the configuration of Ring Frames

• Conclusions

• Ring Frame Design• Points to be noted in this path– Tension in the yarn– Ballooning of the yarn

• Process optimization – End Breakage Rate

FW = 2π2µMD(Ns)2/sin α

• Case I - weightless yarn and no air drag.

• Case 2 – R1TW = RTU sin αo

• Case 3 – R1TW > RTU sin αo

• Case 4 – R1TW < RTU sin αo

• In general, however, the centripetal force effects are greater than those of air-drag and the resultant configuration of the yarn will be as shown in Fig. D.

• The tension in the winding and balloon zone will be at equilibrium and hence

TW = TR eµθ

• According to Klein the value of the eµθ lies in between 1.2 to 1.8.

• Balloon tension will be on an average 50% of the winding tension.

In R/S, its not exactly a tensioned ring.

The yarn length is self-adjusting so that the balloon shape permits the net horizontal force on each element in the yarn just to provide the necessary centripetal force on that element. Air drag is relatively more important with fine yarns than with coarse yarns

• Neck of finite radius• To avoid neck formation R/P and H/P

must be small: i.e. P must be large. • The formation of a neck in the balloon

occurs gradually if unfavourable conditions arise, such an increase of H, or a reduction of traveller mass.

• Balloon collapse arises when the neck contacts the package significantly thereby causing a breakdown in the spinning process.

• Collapse would be most likely to occur when the yarn in winding on to the maximum package diameter with the longest balloon length, i.e. when H is at maximum and P is at a minimum.

• Automatic control of spindle speed

• Programmed control of spindle speed by cam designed

• A two speed drive

• Spinning being carried on with the yarn wrapped around the package spindle.

• The aim of such spindles is similar to that of the use of control rings

• Work required to rotate the balloon is now provided via the tip of the spindle and the winding tension is correspondingly reduced.

• The tension in the balloon and the spinning tension are also reduced.

• Tension and balloon geometry are two co-related phenomenon• End breakage rate• Process optimization for a minimum end

breakage rate• Apart from it we have also seen the newer

configurations that have been incorporated into the ring frame of the modern day

• De Barr, A.E and Catling, H. ‘The principles of ring spinning’ Manual of cotton spinning, Vol V, Textile Institute Manchester, 1965.

• Klein, W. ‘the technology of short staple spinning’, short staple spinning series. The Textile Institute Manchester.• Stalder, H. ‘increasing ring spindle speed in consideration of yarn quality and running condition’ Melliand

International (1994) 7-8, E140.• Schwap, R. ‘yarn tension in ring spinning process’ Melliand International.• Oxtoby, E. ‘spun yarn technology’ Butterworths & Co 1987.• References from the Journal of the Textile Institute.

– Application of theory of spinning – balloon part I– Controlled balloon spinning G. M. Bracewell– Measurements of balloon characteristics J. Gregory and C. Mack– A descriptive account of yarn tensions and balloon shapes in ring spinning A. E. De Barr– The physics of the yarn tensions and balloon shapes in spinning winding and similar processes A. E. De Barr

• References from the Textile Research Journal– The effect of yarn hairiness on air drag in ring spinning– Effect of geometry of ring spinning triangle.– Accurate identification of the shape the yarn balloon.