Penelitian ini bertujuan untuk menganalisis pengaruh variasi diameter puli terhadap kinerja mesin penepung tipe disc mill ffc-15, dengan bahan baku berupa 500 gram biji jagung kering yang digiling menggunakan tiga variasi diameter puli 6 inch, 7 inch, dan 8 inch. hasil penelitian menunjukkan bahwa peningkatan diameter puli secara signifikan mempengaruhi efisiensi penepungan. hasil penelitian ini pada efisiensi penepungan tertinggi dicapai oleh puli berdiameter 8 inch sebesar 86,10%, untuk puli 7 inch yaitu sebesar 50,34%, untuk puli 6 inch yang paling rendah yaitu sebesar 45,96%. pada efisiensi transmisi yang tertinggi yaitu pada puli 6 sebesar 99,88%, selanjutnya pada puli 7 inch yaitu 98,66%, untuk puli 8 inch yaitu 99,68%. dengan demikian, pemilihan diameter puli harus mempertimbangkan keseimbangan antara efisiensi penepungan dan efisiensi transmisi. kata kunci: biji jagung, disc mill ffc-15, efisiensi, puli

The purpose of this study was to analyse the effect of variations in pulley diameter on the performance of the disk mill ffc-15 type flouring machine, with raw materials in the form of 500 grams of dry corn kernels milled using three variations of pulley diameters of 6 inches, 7 inches, and 8 inches. the results showed that increasing the pulley diameter significantly affected the flouring efficiency. the results of this study on the highest flouring efficiency achieved by an 8 inch diameter pulley of 86.10%, for a 7 inch pulley it was 50.34%, for a 6 inch pulley the lowest was 45.96%. the highest transmission efficiency was on pulley 6 at 99.88%, then on a 7 inch pulley it was 98.66%, for an 8 inch pulley it was 99.68%. thus, the selection of pulley diameter must consider the balance between flouring efficiency and transmission efficiency. keywords: corn seed, disc mill ffc-15, efficiency, pulley