CALCULATION, DESIGN AND MANUFACTURE OF HIGH-EFFICIENCY SEED PADDY CLEANING MACHINE

Abstract

Rice is the main food crop in Vietnam, accounting for about 52.56 % of the total cultivated area. Furthermore, the production of rice seeds is one of the main economic activities of the rice growing industry and therefore, it is necessary to fully mechanize the seed processing on a large scale to meet the practical demands. Hence, the objective of this study is to introduce an industrial-scale rice sorting and cleaning machine for rice seed production. In the structure of the machine, there are main parts such as: grain sieve (for sorting), blowing part (for cleaning) and stone separator. Depending on the types of rice seed, the sieve hole size of the sieve unit can be changed accordingly. The performance of the machine is evaluated based on empirical studies at the production factories. The component of rice seed has either heavy or light impurities such as straw particles, mulch and rocks of different sizes. The main parameters of the sieve machine such as sieve area, speed/the number of rotations of the eccentric swing arm, or good aerodynami- efficiency air velocity. The corresponding values when they were surveyed are 1.12 m2, 400 v/min, 15,5-18,6 m/s respecticvely. The separation rate of large, light and same-sized impurities attains an efficiency of approximately 99.63 %, 99.87 %, 99.5 %,. With the aforementioned parameters, the effective productivity of the machine is 955 kg/h and the sorting efficiency of the sieve is about ≈ 99.86 % while the cleaning efficiency for impurities ranges from 99.56 -99.87 %.