PHYSICAL AND MECHANICAL PROPERTIES OF PONKAN MANDARIN APPLIED TO GRADING MACHINE

Abstract

The aim of this research is to study some physical and mechanical properties of Ponkan mandarin, as promising fruits, to help the design of handling machines. The physical and mechanical properties are incorporated in the development of the grading machine as a case study. The main results in this study can be summarized in the following points: Physical properties of Ponkan mandarin fruits: diameter = 58.61 – 85.56 mm, height = 49.45 – 78.9 mm, mass = 70 - 128 g, volume = 60 - 120 cm3, projected area = 41.22 – 81.88 cm2, peel thickness = 2.18 – 3.73 mm, peel mass = 24.2 – 36.1 g, number of segments/fruit = 8 - 12, number of seeds/fruit = 4 - 9, juice volume/fruit = 23 - 34 cm3, and juice volume/fruit mass = 0.24 - 0.45 L/kg. Mechanical properties of Ponkan mandarin: The average of firmness distribution along Ponkan mandarin surface were: the maximum = 18.3 N/cm2 at the top of fruit and the minimum = 11 N/cm2 at the bottom of fruit. The deformation range increased from 2.75 - 3.09 to 8.52 - 10.02 mm by increasing loading from 1 to 5 kg. Meanwhile, the deformation range increased from 2.75 - 8.52 to 3.09 - 10.02 by increasing loading time from 15 to 60 s. Some application to grading machine is given also in the paper as a case study.