There are many casting processes, developed over hundreds of years. The most commonly used are continuous casting, sand casting, investment casting and centrifugal casting.
Continuous casting
Used in steelworks to produce large quantities of simple shapes, such as round bars, square billets, or rectangular blooms and slabs. It has also been developed to produce relatively thin sheets.
Sand casting
The oldest casting process, where a sand mould is made to cast an approximate shape. The surface finish from a sand mould is relatively rough, so it suits parts where the external finish is less critical. Common stainless steel and nickel alloy parts include pump bodies, valve bodies and bonnets.
Investment casting
Also known as the lost wax process, this is typically used to produce large numbers of smaller, more complex shapes with excellent finish and near-net shape. Creating the patterns and moulds can be expensive, which is why it fits longer production runs that amortise the investment.
Centrifugal casting
Used to form tubular products by pouring molten metal onto the inner surface of a rotating mould. It can cost-effectively produce longer or larger-diameter parts that would be expensive to machine from solid bar.