Authors : Basil Okafor , Steve Odi-Owei and P.P. Jombo
Abstract: Tests were carried out on carefully collected samples to determine the mechanical properties and chemical composition of the screws. This is aimed at recommending the best of tribological material for the system. The tensile test result shows that the ultimate tensile strength of the press screws is 1.26E07 KN m � with an overall per cent elongation of 19.1%. Hardness test indicated that the screw is of medium hardness, with a hardness number of HRC40.10. The chemical analysis shows that the screw is a carbon steel with a carbon content of 0.317%, alloyed with Silicon (Si) and Manganese (Mn) elements. A press screw made of silicon-manganese cast steel with 1.20% carbon content, 1.27% silicon and 1.30% manganese is recommended. It is suggested that the material be hardened by heating to 1050°C and quenched in oil. Tempering is at 240°C for 6 h to ensure adequate toughness and minimal loss of hardness.
Basil Okafor , Steve Odi-Owei and P.P. Jombo , 2007. Wear Control in Press Screws in Palm Oil Mill . Journal of Engineering and Applied Sciences, 2: 1058-1060.