Thesis Details

Thesis Title: An evaluation of sized filling with respect to stop levels in rapier weaving
Thesis Author: Ronald Timmons
Abstract: As textile weaving operations strive to obtain world class manufacturing status, the need for higher weaving efficiencies and better yarn quality is required today more than ever before. Weaving machine speeds are increasing with advances in technology and along with this comes an increase in machine price. Therefore, higher machine efficiencies are required to cover machine cost. Although this is an overview of what weaving operations are encountering today, increases in machine speeds place tremendous tension on both warp and filling yarns. These tensions break yarns and as a result, weaving efficiencies are lowered because of machine downtime. To eliminate machine downtime related to insufficient yarn strength, weaving operations will have to slow down their machinery or use yarns of higher quality. Therefore, the objective of this thesis was to reduce filling yarn stops by coating the yarn with size. In addition to coating filling yarns, determine the optimum size pick-up level that would produce maximum weaving efficiency. The final objective of this thesis was to determine whether it was economically feasible to size filling. Yarns of varied structural compositions were used to assess the effect of various size pick-up levels and tension on filling yarns. The Dornier Rigid Rapier machine at the Institute of Textile Technology was used as a sample loom for testing the theories of this thesis. Results of accelerated weaving (five times the normal tension) tests based on filling stops per ten thousand picks were used as an indication of weavability. Conclusion drawn from the results of this experiment were as follows: 1. Variations in size pick-up levels have various affects on weavability of different spun yarns. 2. There were few filling stops for Murata Air-Jet and Open-end yarns at 4% size pick-up. Ring yarns on the other hand, had few stops at 6% pick-up. Four and six percent appeared to be the best size levels for Open-end and MJS yarns during this research. 3. Size reduces filling stops; however, it is not economically feasible to size filling for an entire weaving operation. Under special circumstances where filling stops are excessive because of insufficient yarn strength, sizing filling may be practical.