Abstract:
In this project, a laboratory hammer mill has been designed and constructed with output
crushing force of 23 kN and average crushing strength 12 kN/mm2. The feed crushing
performance varies between 300 and 340 kg/hr of granite rock, depending on the type
of rock to be crushed and screen size. All the components of the machine such as the
hammers, hammer discs, shaft, pulley drive, belt drive and machine casing were
designed and constructed from locally sourced materials. The hammers are normally
made from manganese steel which is scarce locally, the hammer in this work has been
made based on improvisation of spring steel materials to reduce cost. A mild steel shaft
of θ70 mm, 495 mm long made of mild steel were machined using lathe machine down
to θ50 mm, 489 mm long. The power rating of the machine was determined to be 4.0
kW (5.3 Hp) electric motor requiring 415 volts and 50 Hz frequency.
