Sand casting is one of the most successful manufacturing techniques in the world. Sand casting uses temporary sand molds which are used to manufacture complex metallic or alloy parts. The sand mold is destroyed in the process, and the metallic component is subsequently extracted.
In typical sand casting, the molds are constructed out of the sand, and they are broken in order to retrieve the final metallic component. There are three basic components of sand casting: the furnace, the molten metal, the pattern, and the sand mold.
The metallic stock material is melted in the furnace and subsequently ladled and inserted into the cavity of the sand mold which is defined by the pattern. After the metal has solidified, the sand molding is separated, and the solidified metallic component is removed. The various advantages of sand casting are mentioned below.
Advantages of Sand Casting
The sand casting technique is one of the most popular manufacturing technique in the world because of the following advantages that it offers.
- It is the most inexpensive manufacturing processes delivering quality and reliability of manufacturing at a cost-effective rate.
- Sand molds are easily recyclable and thus can be reused.
- Parts created during sand molding can withstand extremely high temperatures without any major deformation.
- It is an extremely flexible process that offers a variety of complicated shapes and structures.
- It is a relatively simple process that doesn’t consume much time or resources.
Sand casting utilizes extremely high temperatures and is hence suitable for metals with high melting points such as steel, nickel, aluminum, and titanium. Due to its resistance to heat, low cost of operation and high reliability, sand casting is one of the most popular manufacturing techniques in the world.
The basic process involves pouring molten metal inside the cavity of the sand mold. The mold is subsequently cooled until the metal solidifies inside the cavity. The sand mold is broken, and the metal is extracted. There is additional bonding material present that increases the ability of the stock material to resist heat and retain its shape.
Important Properties of Sand related to Sand Molding
Some of the important properties of sand that determines the final product are mentioned below.Strength of the Material- The sand that is used to create the specific mold must be able to retain its geometric shape along with the cavities and cores that have been placed inside it. The shape must never collapse while the molten is being poured or during any kind of external pressure.
Sand Permeability- There are a lot of gases released during the sand molding process, the mold must be permeable enough to allow for the escape of these gases.
Flow and Grain Size- The grain size of each and every individual particle involved in the sand mold matters as it plays an important role in determining the final dimensions of the product. Flow matters as it determines the ability of sand to fill out all crevices in the pattern. A high flow rate of sand represents greater precision and in creating detailed features.