Study of shaped castings using vertical centrifugal casting method

Abstract

Centrifugal casting is one of the casting techniques which is most widely used in the modern production of automotive and industrial components. The die casting is replaced with a shaped casting method using a centrifugal casting process, which will increase the properties of the final products. The present work is focused on the fabrication of shaped casting of three-wheeler Differential housing using Aluminium material by vertical centrifugal casting process by varying the Process parameters. Conventionally this part is produced in Cast iron / Steel by Gravity casting / Shell moulding process. The effects of casting parameters through the Vertical Centrifugal casting process are mould rotation speed and temperature of the mould etc, were analysed. The mould speed, pouring temperature, Die Coating for controlling the heat transfer and Microstructure and preheat of the mould are very important factors because at an optimised mould speed the centrifugal force and gravitational downward pull are balanced, and a perfect mould is extracted. After several trials, we have optimised the parameters to achieve a good quality differential housing part. Conventionally, the Centrifugal casting method is used for Axis-Symmetric part like Cylinder liners, tubes, etc. The Differential Case is a Cup-shaped part with a Flange for clamping the case in the gearbox. The Die and Mould were critically designed and manufactured to suit the Vertical Centrifugal Casting machine and appropriate Metal pouring spout is provided to have a uniform metal flow to have a better filling up of the metal inside the annular cavity of the mould. The trial results revealed an excellent filling nature throughout the mould shadow regions, the metallurgical parameters like hardness, porosity and strength were comparable to the specifications. The major advantage over the Differential housing made by Aluminium casting is that the strength to weight ratio of Aluminium Alloy is much better than Steel or Cast Iron and this is very important for the light-weight vehicles.