Probability Model of Fiber Damage and Its Application in the Carding Process

The most intuitive manifestation of fiber damage is the change in fiber length distribution. The predecessors only considered the influence of the original length of the fed fiber on fiber breaking, calculated the average number of breakages on the fiber, and established a probability model of fiber breaking to estimate the fiber length distribution after processing. However, the number of fiber breakages is directly related to processing conditions, and the most direct influence is speed. This paper improves the original fiber damage probability model by considering the joint influence of fiber length and machine speed. The regression equation of key fracture parameters related to carding speed in the fracture probability model was fitted by the stepwise regression method. To verify the improved fiber damage model, three groups of single-factor experiments were designed for the carding process, and the length distribution of output fibers with different speeds of taker-in, cylinder, and doffer was tested by AFIS. The predicted fiber length distributions of the theoretical model are consistent with the measured results. Although the fiber damage model we established has limited ability to extrapolate, it still provides an effective empirical tool for the quantitative description of fiber breakage in the carding process.