Design of the Transmission System for a Charcoal Briquette Molding Machine

Abstract

Biomass and organic waste can be utilized as alternative fuel through a briquetting process. A stable molding process requires a transmission system capable of transmitting power, controlling rotational speed, and providing adequate torque to the screw extruder. This study aims to design the transmission system of a charcoal briquette molding machine and evaluate the feasibility of the pulley through theoretical calculations and static simulation using SolidWorks 2025. The machine uses a 2 HP (1.5 kW) AC electric motor at 1400 rpm, a pulley–V-belt system, a WPA 60 A reduction gearbox, an AISI 1035 shaft, and an ASTM A36 Steel pulley. The design results show a system power of 149 W and a calculated motor power requirement of 169.8 W. The selected motor has a rated power of 1.5 kW and a rated torque of 10.17 Nm, while the required screw torque is 4.23 Nm. An effective 10:1 transmission ratio is used to reduce the motor speed from 1400 rpm to approximately 140 rpm at the screw. The pulley simulation produces a maximum von Mises stress of 8.048 MPa, a maximum displacement of 0.002 mm, and a minimum safety factor of approximately 6.8. These results indicate that the pulley design is safe under the simulated loading condition