Casting is a complex concept, so understanding the basics is necessary before you can look at the disadvantages. Of the many types of casting processes,such as aluminum die casting,investment casting,and stainless steel investment casting, all depend on the materials in question. Some of these techniques include sand casting, investment casting, die casting and metal mold casting. Metal casting is used in a variety of industries, such as automotive, tools, mechanical parts, pipes and valves. The disadvantages differ greatly depending on the casting techniques.
Three major defects are associated with metal casting. Holes are a major area of a concern, which consist of either sand holes or air holes. These appear as small holes or pits on the surface or interior of the metal. Surface holes are not normally a problem, but interior ones make the final product unusable. The second problem is known as shrinkage, which also consists of holes scattered irregularly throughout the product. Unlike sand and air holes, shrinkage cannot be ignored and automatically renders the metal useless. The third defect is cracking. Specifically related to steel, cracking appears once the casting process is complete. Cracking also cannot be ignored.
A serious disadvantage of metal casting is its lack of universality. Although some of the casting methods could be used interchangeably, using the wrong one can be costly or provide an inadequate finished product. Some casting processes, such as mold casting, cannot be used on metals that contain iron. Consequently, this process costs more than other forms of casting. Sand casting is the cheapest process but also the least accurate, thus making it unsuitable for precise work. In short, metal casting requires a trade-off between quality and cost.
Another disadvantage of metal casting is that it is extremely dangerous. People involved in this industrial process must be highly trained, and even then, accidents happen. Molten metal can reach temperatures of over 1,000 degrees Fahrenheit, so one small mistake or equipment malfunction can lead to serious injury or death.
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