Effect of Die Hole Diameter and Motor Speed on the Performance of Machine and Pellet Quality of Castor Shell

Abstract

The study evaluated the effects of die hole diameter and motor speed on machine performance and the pellet quality of castor shell. A flat die pellet machine was tested using three die hole diameters (6, 8 and 10 mm) and three motor speeds (1000, 1200 and 1400 rpm). The measured responses were pelleting capacity, pelleting efficiency, energy consumption, pellet bulk density and pellet durability. The results showed that the 8 mm die hole diameter produced the maximum pelleting capacity and pelleting efficiency, while energy consumption, pellet bulk density and pellet durability decreased significantly as die hole diameter increased from 6 to 10 mm. Increasing motor speed from 1000 to 1200 and 1400 rpm increased pelleting capacity, pelleting efficiency and energy consumption, but reduced pellet durability. Maximum bulk density was obtained at a motor speed of 1200 rpm. The combination of an 8 mm die hole diameter and 1400 rpm motor speed produced the highest pelleting capacity (42.45 kg/h) and pelleting efficiency (95.12 %). The lowest energy consumption (0.89 kW) was observed at the 10 mm die hole diameter and 1000 rpm motor speed. The highest pellet bulk density (456.60 kg/m³) was obtained at the 6 mm die hole diameter and 1200 rpm motor speed, while the highest durability (98.98 %) was recorded at the 6 mm die hole diameter and 1000 rpm motor speed. The findings indicate that die hole diameter and motor speed significantly affected machine performance and the quality of the pellets produced.