Introduction

The aim of this chapter is not to describe the manufacturing processes in detail, but to provide brief information for the various processes that is relevant from the machine design point of view. A designer should have the knowledge of various manufacturing processes while selecting a suitable manufacturing process, as he or she needs to mention the process on the production drawing.

Sometimes a component can be manufactured with various possible methods. In such a case, the designer has to select the method by considering the following factors:

• • Cost of production • Material availability

• • Number of components to be made • Shape of component and

• • Surface finish required

Manufacturing Processes

Manufacturing processes can be mainly classified as under:

Selection of Processes

There are many parameters which decide the type of manufacturing process to be selected. Some processes are such that they finish in one go, while others may need many processes in series, one after the other. Single or multi processes depend on the product. Table 4.1 shows the processes, which follow one after the other.

The process for a product is based on many factors and experience is needed in selecting a process. However, the parameters given in Table 4.2 can give a rough guide line for the selection of a process.

Shaping Processes

Shaping processes involve heating of a material to its melting point and then pouring it into a cavity of the same shape as the component. If the cavity is made in sand boxes called mould, it is called Sand casting. Making a mould is time consuming and hence suitable only for small number of items to be produced.