SHEET METAL OPERATIONS
The major sheet metal operations carried out in sheet metal work are as follows:
1. Cleaning
2. Measuring
3. Marking
4. Laying out
5. Hand cutting
6. Hand shearing
7. Hand forming
8. Edge forming
9. Wiring
10. Joint making
11. Bending
12. Drawing
13. Soldering
14. Circle cutting
15. Machine shearing
16. Nibbling
17. Piercing
18. Blanking
The measuring and marking operations carried over on sheet metal are discussed as under.
Measuring and Marking
The standard sizes of metal sheets available in the market are quite large. But the required sheet size for making a component may be smaller and hence a standard size sheet may have to be therefore cut into several smaller pieces. Each piece must be sufficient for making one such component as per the needed size. Smaller sizes of sheet metal part are first decided and are then marked on the larger metal sheet to cut the latter into small pieces along the marked lines. A little allowance for cutting is always incorporated to the required overall sizes. The overall dimensions of the required smaller sizes are marked on the larger sheet with the help of marking tools such as a steel rule, a straight edge, a steel square and a scriber. The sheet surface may have to be coated with a coloring media so that the scribed lines arc clearly visible. If circular pieces are needed, a divider or trammel may be used to mark the circles.
Source A Textbook of Basic Manufacturing Processes and Workshop Technology by Rajender Singh.