MANUFACTURING OF PISTONS USING CASTING PROCESS TECHNIQUES TO REDUCE DEFECTS

Casting pressure conditions have great influences on the casting defects, Such as gas porosity, shrinkage porosity and gas holes. A Mg cylinder head cover die casting is used to experimentally study the influences of casting pressure, the loading time and the piston position of pressure intensification on the variation of pressure and the quality of casting. The results show that casting pressure, the loading time and the piston position of pressure intensification have great influences on the pressure variations in the mold, the quality and performance of casting. The external quality, the density and the tensile strength of casting are improved with the increase of casting pressure and the piston position of pressure intensification and the decrease of the loading time of pressure intensification. In this first the metal from pre-turning is taken in to the holding cavities and dip these in to the heat treatment furnace up to 500 degree centigrade & maintained time is 5 hours, then here internal stresses will be relieved & then it is removed by using small proclaims& taken in to the quenching furnace for the atomized small grain particles which will be strong enough to bare the loads. In this the pistons from the furnace taken in to solution water which having B.P of 50-60 degree centigrade & maintained up to 30 seconds, then it is going to be further process.

 But now-a-days a new machine called drop quenching furnace is used. It is automatic sensory system. In this process aging& solution takes place one by one.