Optimization and Performance Evaluation of Palm Nut Cracking Machine

An electrically operated palm nuts cracking machine was optimized and its performance was evaluated. The machine was modified by introducing three pulleys with diameters as 82mm, 75mm and 69mm, which produced rotor speeds of 2200rpm, 2, 400rpm and 2600rpm respectively. The rotor speeds were then used to test the designed machine and its efficiency were evaluated. Also a curve casing that leads the materials (palm kernels) to the cracking chamber was introduced. The curve casing was to prevent splashing or flying back of palm kernels during cracking. The machine has cracking chamber, which flap the palm kernel nuts on the stationary hard surface. The designed machine was operated by a 4hp electric motor. The performance test was carried out using two different varieties of palm nuts [Dura and Tenera palm nuts] at three different speeds which include 2200rpm, 2400rpm and 2600rpm, using 80kg, 120kg and 140kg weight of both varieties of palm nuts. Each one was replicated three times. The results show that cracking efficiency of the machine increase as the rotor speed increases. The statistical analysis [ANOVA] for the effect of moisture content, speed of the rotor, feed rate and the interactions on the capacity and performance of the evaluated machine for both varieties of palm nuts at 5 % probability level was computed. The result of the analysis confirms that moisture content, speed of rotor and feed rate are significant processing parameters that affect machine efficiency on difference sizes of palm kernel cracking.