Sand castingis used to make large parts (typically Iron, Steel, but also Bronze, Brass, Aluminum). Molten metal is poured into a mold cavity formed out of sand (natural or synthetic). The processes of sand casting are discussed in this section, include patterns, sprues and runners, design considerations and casting allowance. Sand castings generally have a rough surface sometimes with surface impurities, and surface variations. A machining (finish) allowance is made for this type of defect. Lost foam casting, also known as real mold casting, is a new type of casting method that combines the foam model that is similar to the size and shape of the casting to form a model cluster. After the fire is painted and dried, it is embedded in the dry quartz sand to vibrate and shape. Under the negative pressure, the model is vaporized, the liquid metal occupies the model position, and the new casting method is formed after solidification and cooling. Lost Foam Casting (EPC) is a new technology with near no margin and precise molding. It has no need to take mold, no parting surface and no sand core. Therefore, the casting has no flash, burr and draft angle, and the dimensional error caused by core combination is reduced. The surface roughness of castings can reach ra3.2-12.5 μ m; the dimensional accuracy of castings can reach ct7-9; the machining allowance can be up to 1.5-2mm, which can greatly reduce the cost of machining, and can reduce the machining time by 40% to 50% compared with the traditional sand casting method. Main advantages of Lost Foam casting process. 1. The casting has the characteristics of precise size and shape, good repeatability and precision casting; 2. The surface finish of casting is high; 3. The casting has no flash and burr, which reduces the cleaning and grinding workload by more than 50%; 4. The machining allowance and machining cost are reduced; 5. It is easy to realize mechanized automatic assembly line production, and the production line has great flexibility. It can realize the production of castings of different alloys, shapes and sizes in one production line; 6. The draft angle can be cancelled; 7. The shape of the parts is not limited by the traditional casting technology, which liberates the mechanical design workers and enables them to design the most ideal casting shape freely according to the service performance of the parts; 8. It can reduce the weight of casting; 9. Reduce the production cost; 10. EPC process is not only suitable for castings with simple geometry, but also suitable for castings with multiple open edges, multi cores and complex geometry which are difficult to be cast by ordinary casting; Process: Clay Sand casting, Resin Sand casting, Coated Sand casting, Lost Foam Sand casting. Material used: Steel&Alloy, Ductile Iron, Grey Iron, Iron Alloy, Aluminium, Bronze, Brass. Weight of parts: From Hundreds of grams up to Hundreds of Tons.