There are many factors determined by sand in green. Many factors like casting surface finish, gas permeability of the mold and mold strength. As for the sand, there are also many requirements such like the ability to retain mold shape during packing and pouring in process. The sand also needs high temperature stability. In green sand casting industry, the sand should have permeability for the gases liberated from the mold and solidifying metal. Another ability the sand needs to have is collapsibility with which the sand to be shake out easily. Also there is silica sand with additives is used for green sand casting.
In the typical mold for a green sand casting there are many sets of channels through which a molten metal can flow to the mold cavity which we can call it the gating system of sand casting. The typical gating system involves a pouring cup and a sprue receiving the poured melt, runner is a channel through which the melt can be supplied to the gates through which the molten metal enters the mold cavity.
In green sand casting, there is a gating system which include a riser. When the system is shrinking while casting, the riser cavity which is linked to gating part can feed the casting. There also has a vent which can let the air go outside if air and gas formed in the mold cavity while the molten metal gets contact with the mold surface. So our green sand casting equipment is very efficient system for manufacturing foundry products.