Sand casting is the oldest casting process that exists. It uses patterns made of metal, wood, or wax to create models of the desired object. The sand casting process is complicated and has a slow production rate. This is due to the destruction of the sand mold when removing the casting (the item produced). The process involves the use of patterns, sand molds, furnaces, and liquid metal.
Well, in this article, I’ll be discussing sand casting, its definition, process, applications, advantages and disadvantages.
What is sand casting?
Sand casting is a manufacturing process in which molten metal is poured into a sand mold containing a hollow cavity of the desired shape. The mold is made of sand particles held together with an inorganic binding agent. This casting is then allowed to cool at room temperature before the sand mold is broken and the object is removed.
Some of the materials involved in this process include metal, concrete, epoxy, plaster, and clay. Some of the tools used during the casting process are hand riddle, shovel, rammer sprue pin, mallet, etc. Well, you can read the full article on sand-casting tools here.
The foundry is the place where casting is carried out, and the process is called foundry work. Just as earlier mentioned, sand casting has been around for thousands of years. It was first introduced in 1000 BCE and has been adopted all over the world. Ever since, there has been improvement in process control, material options, tolerance capabilities, complexity in shapes, object size, and many more.
Despite the advancement of the sand casting process, the process remains the same, which includes pattern making, molding, melting, pouring, ejection, cleaning, fettling, and inspection. You can learn the step-by-step stages of how the sand casting is done here. Although defects are inevitable, some of them could even damage the entire casting. This is why all foundry workers are highly skilled, as the process also involves serious safety.
Despite being an old process, sand casting is still one of the most common and widely used. This is because it still offers great benefits in various fields, such as automobiles, agriculture, medical, construction, and marine. This is because sand casting is used for heavy equipment.
Sand casting is most frequently used to create intricate shapes that would be challenging or expensive to create using alternative techniques. Instead of constructing heavy equipment by combining numerous small pieces, large pieces of heavy equipment, such as machine tool beds and ship propellers, can be conveniently cast in the needed size.
Sand casting has advantages over other casting processes, even though several defects may occur. Sand casting offers great strength when clay is added to the mold, making the sand strongly bond.
Sand casting is designed to reduce the potential for cracking, tearing, and shrinkage during the cooling stage of the casting. Sand casting is used mostly in producing automotive products, such as engine blocks, casings, and housings. Some other advantages of the sand casting process include:
- Both ferrous and nonferrous metals are used for casting.
- Low cost of production.
- Low cost for post-casting tooling.
- Complex shapes can be produced.
Despite the excellent benefits of sand casting, some drawbacks still occur. Below are the disadvantages of a sand casting process in its various applications.
- A lower degree of accuracy
- It is a tedious process
- Rough surface finish
- Mold can only be used once
- Slow production rate
- Labor intensive
That is all for this article, where I have quickly explained the definition, applications, advantages, and disadvantages of sand casting. I hope it was helpful; if so, kindly share it with others. Thanks for reading, see you around!