Metal castings have many different applications in industrial settings. Castings are essential for producing various items required for end-product manufacturing. In addition, castings allow manufacturers to produce items to the exact specifications that they prefer.

For metal castings such as bronze to be produced in high quality, there are several basic processes that must be carried out in sequential steps. Each of the following processes will be necessary to produce a bronze casting of unique dimensions and characteristics.

1. The pattern-making technique

All bronze castings begin with pattern making. The pattern is essentially the outline that will define the final dimensions of the casting itself. It defines the shape, contraction and expansion capabilities, and machining methods that will be used.

The pattern also defines the final characteristics of the casting once it finished, influencing its use in any final products. It is important to select the right pattern as a starting point for any metal casting.

2. Moulding

After a pattern is prepared, it should be moulded to achieve the 3-dimensioanl shape of the actual casting. In most cases, an impression of the pattern is taken (using a binding material) and placed in a mould core. The mould core is the housing that contains the exact dimensions needed for the casting itself.

Additives are normally incorporated into the moulding to keep its structural integrity. A coating may also be added to the mould to achieve a desired finish on the surface.

3. Melting

Melting is often carried out to create metal alloys that can improve the usability of the casting itself. Melting is typically done in electric furnaces, where all constituent metals are first analysed for their purity.

Machines are used to prepare the specific ingredients of the metal alloy, after which melting is carried out in a highly controlled environment.

4. Shot blasting

Shot blasting is an intermediate process where the melted alloy from the previous step is cleaned from impurities. During shot blasting, sand and other debris are removed from the mould after it is allowed to cool and solidify.

Other materials that are adhered to the casting can be removed through the use of pedestal grinders.

5. Heat treatment

Before any metal casting can be used in a final product, it must first be heat-treated. Heat treatment ensures structural integrity, proper composition, and stress resilience of the metal casting.

Heat treatment involves a variety of processes, such as normalising the metal, annealing, and precipitation hardening.

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