Melting and pouring in sand casting is the process of heating solid metal to a fully molten state and pouring it into molds. This stage requires precise temperature control to ensure proper fluidity and avoid oxidation or contamination. During pouring, the molten metal must flow smoothly and at a controlled rate to completely fill the mold cavity. Proper melting and pouring practices help prevent defects such as misruns, cold shuts, and excessive porosity.