Effect of Moisture Content on the Angle of Repose and Coefficient of Kinetic Friction of Sago Trunk (Metroxylon spp.)

Starch is one of the food sources that can be extracted from cereals, roots, tubers and stem. Sago palm (metroxylon spp.) example starch source. The efficiency extraction process depends on mechanical properties material. This study was conducted to determine angle repose between grated sago kinetic friction contact surface material machine. (θ) determined by using a cone shape hopper attached an adjustable height bar. filled with 100g sample slowly adjusted upward direction release will form conical shape. base diameter were measured. Next, square block debarked trunk (8cm × 8cm 8cm) placed stainless steel plate rope at middle connected force gauges. pulling speed 1.27 mm/min result total load (F) recorded. repeated for materials different moisture content (MC) 60%, 50%, 40%, 30%. Based experimental results, (AoR= 47.000±0.31) coefficient (μ k) 0.88±0.005 MC= 60% showed decrease in value 43.610±0.34; μ k = 0.83±0.002) when MC 30% (P<0.01).