Correct Answer - Option 4 : All of the above
Explanation:
Casting: It is a manufacturing process in which liquid material is filled into the mould, which contains a hollow cavity of the desired shape and then allowed to solidify. The solidified part is known as a casting, which injected or broken out of the mould to complete the process.
Mould
A mould is an assembly of two or more flasks (metallic) or bonded refractory particles with some cavities.
According to the material used in their construction, the moulds are of the following type
- Green sand moulds
- Dry sand moulds
- Loam sand moulds
Proper mould dressing is necessary for a better surface finish.
Pattern Finish:
- Pattern finish is a vital feature in pattern design as it affects the dimensional characteristics of the casting.
- Thus, when the pattern is produced, certain allowances must be given on the size specified in the finished component drawing so that casting with the particular specification can be produced.
Sand Compactness
- The method of compaction in sand moulding influences surface finish at all levels. Sand grains that are packed tightly produce a more uniform surface over which molten metal will eventually flow, mimicking the appearance of the sand itself.
- Hand ramming makes for the worst compaction. Blowing produces a smoother surface than hand ramming, while the jolt-squeeze method provides an even smoother, more compact mold than blowing. Automatic molding machines also generate superior surfaces.
