Correct Answer - Option 4 : Sweep pattern
Explanation:
Loam Moulding: It used for making cast iron or bronze cannon and is still used for casting large bells. For some very large castings, moulding boxes and patterns cannot be used. Such large castings are made by the use of loam moulding.
- Loam is a mixture of sand, water, and a large amount of clay. It is in a paste form.
- First, a rough framework is made of bricks.
- The loam plaster is applied over the brickwork.
- A sweep pattern is used to get the required shape of the mould.
- Plates and bars can be used to reinforce the brickwork.
- This loam mould is then dried.
- Now the mould is ready for pouring.
- Cores can be made by this process.
- Loam moulds are also made by using skeleton patterns
Application of Loam Moulding:
- Large cylinders, large bells, round-bottomed kettles, chemical pans, large gears, and other machine parts are produced by loam moulding.
Advantages of Loam Moulding:
- Large castings can be made without patterns and moulding boxes.
- Castings will have a very good surface finish.
- Accurate castings can be produced.
