The cores are defined as sand bodies used to form the hollow portions or cavities of desired shape and size in the casting. Thus the sand used for making these cores is called core sand. It is sometimes called oil sand. It is the silica sand mixed with linseed oil or any other oil as binder.
The property which enables it to resist high temperature of the molten metal without breaking down o r fusing.
The property of sand to resist chemical reaction with molten metal is termed as chemical stability.
Dry Sand Moulding :
- Complicate designs required for engines and automobiles can be designed with relative ease
- Accuracy is terms of dimensions, size, designs, is the main benefit
- Though an expensive process, here accuracy is maintained in every respect
- A process is favored by large foundries.
Green Sand Casting :
Molds for sand casting :
- A reasonably priced process, green sand casting enables great flexibility in the choice of molds and patterns.
- This is an environmental friendly process where there mold aggregated can be treated and repeatedly used.
- This process enables speedy, economical and expeditious execution of the casting process
- Easily adaptable to automated and semi-automated machines for some process.
- The aggregate and adhesives are readily available at reasonable rates.