Rice straw consider one of the main problems face agriculture production in Egypt and its assembly caused a bad effect on environment, , therefore use rice straw pieces in animal fodder as mixture with clover consider one of the most suitable solve of this problem.
The main aim of this study, developed and manufactured mechanism attached local rice straw cutting machine solving jamming of rice straw during feeding process to consequently irregular cutting process, resulting in similar rice straw pieces.
Developed mechanism tested with rice straw material; there are three variable factors to evaluate the ability of developed mechanism to cut rice straw into similar and small peaces. The first one, four ratios between feeding drums rotating speed (Sf) to cutting drum rotating speed (Sc), 1/2, 1/4, 1/6 and 1/8 respectively. second factor, number of knives on cutting drum (N) 2 and 4 knives. Third factor the concave clearance between cutting drum and concave of its housing (Cc) 2, 4 and 6 cm. To evaluate the influence of previous factors there were theoretical study done to calculate the length of straw pieces at previous factors under study, and then compare the theoretical calculated and actual rice straw pieces after cutting process to estimate the factors that gives the similar and smallest rice straw pieces. The final results of this study can be summarized as follows:
The problem of jamming solved after modifying feeding device attached the cutting machine with new technique. the smallest length of rice straw pieces (1.8 cm) obtained at number of (4 knife) on cutting drum and the highest value of ratio between feeding drum rotating speed to cutting drum rotating speed (Sf / Sc =1/8) with concave clearance (Cc = 2 cm).