Effect of pre-squeezing force in a single-sizing-roll triple-roll-type sizing machine on size pick-up and quality indexes of sized yarns

Cotton warp sizing is the precondition for guaranteeing smooth weaving. Pre-squeezing is one of the processes for sizing in modern multi-squeezing roll sizing machines, which plays a positive role in the rational distribution of sizing material in sized yarn. However, the effect of pre-squeezing force on the properties of sized yarn is not clear. In this study, the mixed size liquor of starch acetate and PVA 088-05 was modified to reduce its viscosity at room temperature; subsequently, the warp yarns were sized by a single-sizing-roll triple-roll-type sizing machine. The effect of pre-squeezing force on the size pick-up and quality indexes of sized yarns was investigated. The results revealed that there was a positive correlation between pre-squeezing force and the size pick-up of sized yarn. The breaking force, abrasion resistance, abrasion residual breaking force, and hairiness number of sized yarns first increased and then decreased as the pre-squeezing force was increased. The analysis of variance indicated that pre-squeezing force significantly affected size pick-up percentage, breaking force and elongation, abrasion resistance, and hairiness of sized yarns. This study clarifies the relationship between pre-squeezing force and sized yarn quality indexes, which can offer a beneficial reference for the selection of pre-squeezing force in sizing production.