Moulding Sands:

Foundry sand consists primarily of clean, high-quality silica sand, consistently sized or lake sand that is bonded to make moulds for ferrous (steel and iron) and non-ferrous ( aluminum, copper brass) metal castings. Though these sands are clean prior to use. The automotive industry and its parts suppliers are the main generators of foundry sand.

In the foundry industry the most common casting procedure utilized is the sand cast system. Virtually all of sand cast moulds for ferrous castings are of the green sand kind. Green sand consists of high-quality silica sand, approximate 10 % bentonite clay (as the binder), 2 to 5 % water and approximate 5 % sea coal (a carbonaceous mould additive to develop casting finish). The kind of metal being cast determines that additive and what gradation of sand is utilized. The green sand utilized in the procedure constitutes 90 % of the moulding materials utilized.

Additionally to green sand moulds, chemically bonded sand cast systems are also utilized. These systems include the use of one or more organic binders (typically proprietary) in conjunction along catalysts and different hardening/setting process. Foundry sand makes up approximate 97 % of this mixture. Chemically bonded systems are most frequently used for "cores" (utilized to produce cavities that are not practical to create by normal moulding operations) and for moulds for non-ferrous castings.