This set of Foundry Questions and Answers for Aptitude test focuses on “Type of Sand Moulds”.
1. _________________ is a container which when poured with molten metal produce a casting of the shape of the mould.
Explanation: Prepared molding sand is packed rigidly around a pattern and when the pattern is withdrawn, a cavity corresponding to the shape of the pattern remains in the sand and is called as the mould.
2. In Green Sand Mould, the molten metal is poured while it is in a wet state.
Explanation: The non-dried condition of the sand is called as the green sand condition. It is used in damp condition and contains free water. Hence the molten metal is poured while it is in the wet state to ensure better quality castings.
3. Dry Sand Moulds are used for small and medium sized castings.
Explanation: Dry Sand is nothing baked Green Sand. The moulds are filled with the green sand and then the entire mold is dried in ovens before molten metal is poured They have high strength and permeability. Hence, the dry sand moulds are used for large castings as they are not suitable for small castings.
4. _____________ Binders are used to harden the skin dried moulds.
a) Linseed Oil
b) Marine Oil
c) Vegetable Oil
d) Synthetic Resins
Explanation: Linseed oil is added with molding sand in the green condition and then the skin of the mould cavity is dried up with the help if gas or flame torches. The structure after drying appears to be like dried skin. Hence the name is Skin dried moulds.
5. ______________ is made by assembling a number of cores made individually in separate core boxes and baked.
a) Dry Sand Mould
b) Air dried Mould
c) Skin dried Mould
d) Core Sand Mould
Explanation: The cores are made with recesses and projections so that they can be fitted together to make a mould. Hence, a core sand mould is said to be an assembly of such components.
6. Metal Mould provide high dimensional accuracy.
Explanation: Metal Moulds are permanent moulds. It is manufactured by casting and consequent machining of the mould cavity. Hence the dimensional accuracy got is high. The Metal moulds retain their shape for longer time and provide dimensional accuracy.
7. _____________ is used to make a metallic die in Investment mould.
a) Sweep Pattern
b) Master Pattern
c) Single Piece Pattern
d) Skeleton Pattern
Explanation: The surface finish and the accuracy in dimensions of the castings are high in Investment mould. Hence, the master pattern is used in the Investment mould. The pattern is reusable as well.
8. _________ is produced with the help of heated iron/steel patterns.
a) Loam Mould
b) Shell Mould
c) Ceramic Mould
d) Metal Mould
Explanation: Shell mould is a mixture of fine sand and phenolic resin used to produce shells. Shells are assembled to form mould which is poured with molten metal. They give a good surface finish and dimensional accuracy. Hence they are produced with steel and iron.
9. A Ceramic Mould is used to produce thin sections of the high melting point metals and alloys.
Explanation: A ceramic mould can produce castings which do not need machining. They have an excellent ability to cast high melting point alloys to accurate dimensions irrespective of the thickness of the materials due to their ability to withstand high temperature.
10. IC Engine pistons are cast in ___________
a) Investment Moulds
b) Shell Moulds
c) Metal Moulds
d) Ceramic Moulds
Explanation: IC Engine pistons are made up of Aluminum alloy. The IC Engine piston requires a good surface finish and fine grain structure and hence they are made using metal moulds.
Sanfoundry Global Education & Learning Series – Foundry and Forging.
To practice all areas of Foundry for Aptitude test, here is complete set of 1000+ Multiple Choice Questions and Answers.