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Cheek (casting)
A core is a device used in casting and moulding processes to produce internal cavities and reentrant angles (an interior angle that is greater than 180°). The core is normally a disposable item that is destroyed to get it out of the piece.. They are most commonly used in sand casting, but are also used in die casting and injection moulding. For example, cores define multiple passages inside cast engine blocks. One model of GM V-8 engine requires 5 dry-sand cores for every casting. Materials required to make cores *Core sand *Bentonite clay *Pulverized coal *Resin oil Advantages and disadvantages Cores are useful for features that cannot tolerate draft or to provide detail that cannot otherwise be integrated into a core-less casting or mold. The main disadvantage is the additional cost to incorporate cores. Requirements There are seven requirements for cores: #Green strength: In the green condition, there must be adequate strength for handling #In the hardened state, it must b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Casting
Casting is a manufacturing process in which a liquid material is usually poured into a mold, which contains a hollow cavity of the desired shape, and then allowed to solidify. The solidified part is also known as a ''casting'', which is ejected or broken out of the mold to complete the process. Casting materials are usually metals or various ''time setting'' materials that cure after mixing two or more components together; examples are epoxy, concrete, plaster and clay. Casting is most often used for making complex shapes that would be otherwise difficult or uneconomical to make by other methods. Heavy equipment like machine tool beds, ships' propellers, etc. can be cast easily in the required size, rather than fabricating by joining several small pieces. Casting is a 7,000-year-old process. The oldest surviving casting is a copper frog from 3200 BC. History Throughout history, metal casting has been used to make tools, weapons, and religious objects. Metal casting history and de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
