Abstract
The refractoriness is one of the essential properties of the moulding sand in steel castings.
It is supposed that the refractory skin of the mould is necessary to get better surface in the casting.
In the present investigation, it was found that this skin of the mould was within 1-2mm in the small steel casting of about 30mm thickness.
So it was found that the small steel casting could be produced by floor sand or river sand mould coated with high refractory materials.
Then, this idea will be developed to thicker castings by investigating the refractoriness and coating method.
