The most important factor affecting slub yarn smoothness, hairiness and yarn breakage rate is the matching of ring and traveller. This is because in the spinning process of slub yarn, the roughness and detail alternately pass through the traveler, the balloon convex shape fluctuates greatly, the yarn tension is very unstable, the wear between the traveler and the ring is large, if the traveler rotates very unsteadily, the yarn hairiness is more, the slub roughness and the broken ends increase. Therefore, slub yarn puts forward higher requirements for rings and travellers.
01
Selection of traveller type
The type of travelling ring is mainly selected according to the type of ring, that is, the geometric shape of travelling ring and the cross-section shape of wire should be compatible with the shape of ring cross-section, inner runway structure and side width. The common types of flat ring travellers are G, GO, OSS, 772, FO, 6802 and 6903. In spinning medium and fine slub yarn, FO, 6802 and 6903 travellers have fewer hairiness and less broken ends. G and GO travellers are suitable for spinning coarse slub yarn.
02
Selection of traveler number
The number of travellers represents the quality (weight) of travellers. It is based on the standard (metric system) of the quality (weight) of every 100 travellers. The larger the number, the heavier the travellers. When spinning slub yarn, the number of traveller should be selected according to the yarn variety, yarn density, ring diameter, spindle speed, new and old degree of ring, temperature and humidity in workshop, etc.
One
Selection of Slub Yarn Varieties
Common slub yarn varieties are pure cotton, pure polyester, pure viscose, polyester-cotton blending, polyester-viscose blending, linen-cotton blending and so on. Under the same special conditions, the number of travellers of spun chemical fiber slub yarn is 3-5 larger than that of spun pure cotton slub yarn, and the number of travelers of spun pure polyester slub yarn is 1-2 larger than that of spun pure viscose yarn. The number of travellers of polyester-cotton blended slub yarn is determined according to the blending ratio of polyester fibers and cotton fibers. The content of polyester fibers is more and the number of travellers is larger. The number of travelers of polyester-viscose blended slub yarn is similar to or slightly smaller than that of pure polyester slub yarn. The number of travellers of ramie-cotton blended slub yarn is close to that of pure cotton slub yarn or 1-2 in weight.
Two
Selection according to slub yarn density
Slub yarn density can be expressed by base yarn density and average yarn density. When determining the number of travellers, it is mainly determined by the average linear density of slub yarn. Considering that the breaking strength of slub yarn is lower than that of flat yarn with the same special number, the number of traveler numbers of slub yarn is 1-2 smaller than that of flat yarn with the same special number.
Three
Selection according to ring diameter
As the diameter of ring increases, the winding tension of yarn increases, and the number of traveller should be small (light) to master. In order to increase the winding capacity of tubular yarn and reduce the number of yarn dropping, large diameter ring is usually used in spinning medium-sized and extra-thick slub yarn. The number of traveler rings with diameter of 45 mm is generally 1-2 smaller than that with diameter of 42 mm.
Four
Selection according to ingot speed
The spindle speed is high, the traveller rotation speed is fast, the yarn tension is big, the traveller number should be small (light) to control, reduce the yarn tension, reduce the broken ends.
Five
Selection according to the old and new degree of steel ring
The friction coefficient on the surface of the new ring is large, the friction resistance on the travelling ring is large, the yarn tension is large, the number of travelling ring is small (light) and the number of travelling ring is 2-3. With the prolongation of the service time of the ring (3-4 months after the ordinary ring is used), the friction coefficient on the surface of the ring decreases, the yarn tension decreases, the balloon bulges, and the yarn hairiness increases. More, more broken ends, at this time should increase the number of (heavy) traveler.
Six
Selection according to workshop temperature and humidity
Workshop humidity is high, friction coefficient between traveller and ring is large, yarn tension is large, traveler number should be small (light) to master. Workshop humidity is small, air drying, friction coefficient between traveler and ring is small, yarn tension is small, traveler number should be large (heavy) to master. But for pure cotton slub yarn, the workshop humidity is small, the moisture regain of cotton fiber is low, the yarn strength is low, and the number of traveler is too large to increase yarn breakage, so the specific problems need to be specifically analyzed.
