The objective of this research was to study the design factors of the axial-flow corn shelling unit affecting losses and power consumption. The shelling unit was 0.90 m long with a diameter towards the end of the peg tooth of 0.30 m. Design factors comprised of five levels of peg tooth clearance (PC), 25.4, 50.8, 76.2, 101.6, and 127.0 mm, five levels of concave rod clearance (CR), 15, 20, 25, 30, and 35 mm, and five levels of concave clearance (CC), 10, 15, 20, 25, and 30 mm. The experiments were conducted based on response surface methodology and central composite design. The results of this study show that PC, CR, and CC were found to have significant impact on the shelling unit loss and power consumption, but not on grain breakage. Increase in PC and CC or decrease in CR had a trend to increase shelling unit loss. Increase in PC, CR, and CC resulted in less power consumption. Empirical models were constructed based on multiple linear models to define the behavior of the shelling unit loss and power consumption, with R2 of 0.92 and 0.72, respectively.
