In the procedure processes of Robusta coffee initial from bring the green coffee after dried and removed the outside shell and bring it to separating process. The sale price depends on the size of green coffee. If their size of still standard the sale price have been increased. Most of the separating process is majorly with the labor experience. Based on human experience the error with operating and working time is increased. In this reason we will study to the criteria of Robusta coffee for designing and creating the Robusta coffee bean separator machine for Robusta size standard testing. The separator machine consists of the three-layer cylindrical sieve set and the diameter of the layers was 4 6 and 7.5 mm. respectively. For the standardization of Robusta coffee bean is controlled by size of hole sieve. In this research considers to 4 importance parameters by the efficiency of sorting out standard of green coffee Specific Energy Consumption [SEC] and assessment way economic engineering. The result of research shows that the maximum efficiency of green coffee separating is 164.7 kg/hr under the condition of testing with 14.4 rpm at 4 angle incline. In term of standard it found that the machine can separated only for standard and smaller than standard size of green coffee and the maximum moistness are 9.9%. For the least Specific Energy Consumption [SEC] is 0.01631 MJ/kg and occur with the same condition of experiment. Based on this condition the Break-Even Point must be sorting out with 1070550 kilogram per year and Payback Period will occur at 3.598 years. However the quantity of separating or the efficiency of machine is mainly effect to Break-Even Point and Payback Period.

The aim of this research is to design and create the sorting machine within the engineering knowledge by using the three-layer sieve set cylindrical sorting machine under the various conditions of experimental. Furthermore the Specific Energy Consumption [SEC] of Robusta coffee bean separates the standard size of Robusta coffee bean the total of product separated are regarded. For the experiment condition rotation speed adjustable to 9.6 and 14.4 rpm. The raw material flow through to sieve and determination the standard size for calculating the [SEC]. The result of experiment found that the average of total of product separated was 165.1 kg/hr. and 164.7 kg/hr or 99.57% from that were passed the criteria of standard according to the ministry of agriculture cooperative. In order to the [SEC] the cylindrical sorting machine was 0.01631 MJ/kg at 14.4 rpm of rotation speed. However the values of [SEC] may be change from the effect of rotation speed of sieve set.