Improved civilization is due to improved quality of products, proper selection of design as well as
manufacturing process from raw materials to finished goods.
Classification of manufacturing processes:(a)
Metal Casting Process:Metal Casting is one of the oldest materials shaping methods known. Casting means pouring molten
metal into a mould with a cavity of the shape to be made, and allowing it to solidify. When solidified,
the desired metal object is taken out from the mould either by breaking the mould or taking the mould
apart. The solidified object is called the casting. The process is also called foundry.
Any intricate shape can be produced.
Possible to cast both ferrous and non ferrous materials
Tools are very simple and expensive
Useful for small lot production
Weight reduction in design
No directional property
Accuracy and surface finish are not very good for final application
Difficult to remove defects due to presence of moisture
Application:Cylindrical bocks, wheels, housings, pipes, bells, pistons, piston rings, machine tool beds etc.
Casting terms:Flask- It holds the sand mould intact. It is made up of wood for temporary application and metal for
long term use.
Drag- Lower moulding flask
Cope – Upper moulding flask
Cheek – Intermediate moulding flask used in three piece moulding.
Pattern - Replica of final object to be made with some modifications. Mould cavity is made with the
help of pattern.