It is difficult to classify the exact number of various engineering manufacturing processes existing and are being practiced presently because a spectacularly large number of processes have been developed till now and the number is still increasing exponentially every year with the growing demands and rapid progress in science and technology in the manufacturing field.
However, all such manufacturing processes can be broadly classified into four major groups as follows:
(i) Shaping or forming process
Manufacturing a solid product of definite size and shape from a given material taken in three possible states:
- In solid state – e.g., forging, rolling, extrusion, drawing etc.
- In liquid or semi-liquid state – e.g., casting, injection molding etc.
- In powder form – e.g., powder metallurgical process.
(ii) Joining process
(iii) Removal process
It includes machining (Traditional or Non-traditional), Grinding etc.
(iv) Regenerative manufacturing process
Production of solid products in layer by layer from raw materials in a different form:
- Liquid – e.g., Stereolithography
- Powder – e.g., Selective sintering
- Sheet – e.g., LOM (Laminated Object Manufacturing)
- Wire – e.g., FDM. (Fused Deposition Modelling)
Out of the above-stated groups, Regenerative Manufacturing is the latest one which is generally accomplished very rapidly and quite accurately using Computer Aided Design (CAD) and Computer Aided Manufacturing (CAM) for Rapid Prototyping and Tooling.