Investigation of Foundry Properties of Oshogbo and Saki Silica Sand Deposits

Abstract

The quality of moulding sand used in foundry usually exerts significant influence on cast properties. It is therefore imperative that the moulding characteristics of a green sand deposit are established prior to its application. This work compares the foundry properties of moulding sand from River Osun and Saki with a view to determining their suitability for casting household utensils. In addition, it also investigated the effect of termite hill activities on moulding sand. Samples of the sands were obtained from different locations within the deposits in Oshogbo and Saki respectively. AFS sieve analysis was performed on the sand to obtain 600 µm grain sizes. These compositions were later mixed in different proportions and then subjected to green and dry compression strengths, shatter index, permeability and moisture content tests. The results obtained indicated that Oshogbo sand deposit has superior green and dry compression strengths values of 16.35 kN/m2 and 14.49 kN/m2 over that of Saki which exhibited 9.3 kN/m2 and 8.3 kN/m2 respectively. The highest permeability of 193 ml/min was demonstrated by Saki compared with 79 ml/min by Oshogbo deposits while the difference in their moisture contents is insignificant. The shatter index of 64 % and 72 % was obtained for Oshogbo and Saki sands respectively. These results demonstrated the possible utility of both sands for making of sand casting moulds. However, Oshogbo deposit is recommended for its higher fraction of the 600µm grain being the preferred size with demonstrable foundry sand desired properties.