Dimensional Stability Testing After Heat Setting
topic
Heat set yarn dimensional stability is verified by boiling water shrinkage measurement per DIN 53840 comparing skein length before and after 30-minute boiling water immersion, hot air shrinkage at service temperature, and by fabric knitting trials measuring the dimensional change after washing and drying cycles, with shrinkage below specification indicating incomplete heat setting requiring reprocessing or higher setting temperature.
Role
Verifies that heat setting has achieved the required level of dimensional stabilisation that will prevent unacceptable dimensional change during downstream wet processing and consumer care, with boiling water shrinkage being the standard acceptance test for heat set yarns where any residual shrinkage potential will cause dimensional change in fabrics during dyeing and finishing that cannot be corrected without significant reprocessing cost.