Cotton cleanability: part II: effect of simple random breakage on fiber length distribution

Authors: Robert Jr, Kearny; Price, John; Cui, Xiaoliang

Submitted to: Textile Research Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/5/1998
Publication Date: 2/1/2000
Citation: Robert Jr, K.Q., Price, J.B., Cui, X. 2000. Cotton cleanability: part II: effect of simple random breakage on fiber length distribution. Textile Research Journal. 70(2):108-115.

Interpretive Summary: This is the third work in a series devoted to development of a comprehensive understanding of cotton processing quality through a better scientific description of cleanability. The overall problem being addressed is to solve the optimization relationship between cleaning and fiber damage. The relevance to the cotton industry is that an optimum trade-off between cleaning and processing damage can improve the profitability of manufacturing, as well as the quality of the textile product. So an understanding of the balance between cleaning and damage is necessary in order to optimize the economic value and utilization of cotton. The first part of the project deals specifically with the damage side of the problem. Since the principal manifestation of processing damage to raw cotton is incremental fiber breakage, technology for measuring and interpreting fiber breakage is being sought as part of the solution. Previously, a practical method for quantifying fiber breakage was proposed and confirmed experimentally for the simplest form of fiber breakage. In the present part, the method is extended to more complex types of breakage which are more inclusive of mill processing environments. This model is of significant benefit to the cotton production and textile processing industries.

Technical Abstract: Following an approach reported earlier, random fiber breakage during processing and cleaning was studied by applying regulated degrees of random breaking damage in the form of fixed-gage cutting to an experimental cotton sliver substrate having a known fiber length distribution. A fiber-breakage model of cotton fiber length was used to simulate the changes in the shape of the fiber length distribution resulting from damage due to production and mill processing. In the last paper of this series, the method was applied to the case of simple random fiber breakage (long-gage cutting). The present work extends the model to complex types of breakage mechanisms (short-gage cutting) which are more dominant in textile mill utilization. It is shown that this model predicts a distinctly different response of some fiber length statistics to incremental damage depending upon whether the breaking gage for the incremental damage process is longer or shorter than the longest fibers in the distribution. This experiment demonstrated that upper quartile length, uniformity, and coefficient of variation had a discontinuous response to breakage probability at short gage lengths (multiple-break phenomena). Short fiber content was linear at long (single-break) gage lengths, but became nonlinear at shorter gages. Mean length varied linearly with damage over the entire range of long and short gages studied. It was concluded that the use of uniformity and upper-quartile length statistics to track fiber length quality during cotton processing may be misleading. Limits on the usefulness of specific cotton quality properties are suggested by the model.