On the capacity of prepared cane to penetrate grooved surfaces

Grooved rolls form a crucial part of current milling practice. They are required to enhance both friction between the bagasse blanket and roll surface and to allow a low resistance path for juice drainage. Current mill setting procedures are based on a definition of work opening which assumes that the bagasse penetrates to the bottom of the roller grooves. The resulting work opening is then used to calculate compaction, which is used in empirical models for roll load, torque and reabsorption factor. Results are presented from controlled uniaxial laboratory experiments, which suggest that bagasse does not penetrate to the base of grooves under typical milling conditions. The effect of a wide range of groove geometries and speeds of compression is reported. Practical implications such as the effect of groove geometry on energy required for compression are discussed.