Response of Cotton Bale Moisture, Thickness and Force to Changing Environments

Abstract

Moisture transfer in cotton bales, the change in bale thickness, and the change in bale tieforces required to restrain the bale are strongly influenced by the density of bales, the storageclimate, and the permeability of the protective covering on the bales. These conclusions werereached based on a three-phase study. In Phase I, eight bales of cotton were packaged at universaldensity and stored without bagging at ambient conditions for 81 days. The bale thickness and tieforce were measured periodically and the bale weights were taken before and after the storageperiod. The same eight bales were randomly placed in four different types of bagging and stored at26.7 C (80 F) and 80% relative humidity (RH) for 100 days (Phase II). The bagging included twotypes of experimental bagging and two types of standard bagging. The experimental bagging wasless permeable than the standard bagging. Then, the same bales were stored for 305 days at 21.1C (70 F) and 50% RH (Phase III). For Phases II and III, the bales were weighed and theirthickness and tie force measured about twice weekly. The bales gained moisture for Phases I and IIbut lost moisture (weight) for Phase III. In Phase I, bale thickness and tie force increased initiallyafter storage and then responded to the fluctuations in climatic conditions. During Phase II at 80%RH, the bale thickness and tie force increased. However, during Phase III at 50% RH, the thicknessand the tie force decreased. The experimental bagging restricted the moisture transfer (change inweight) more than the standard bagging.