milling machines,drilling and milling centers and sawing machines
Milling is a very similar cutting process to that of drilling.As in the case of drilling,the main rotary cutting movement is produced by the tool .However,the feed motion is not in the axial direction of the cutting tool,but mainly in a vertical direction.
The most important milling operations are illustrated in Fig 7.35. The roller milling and end-milling methods are mainly used for the production of flat surfaces.
Through the use of gang milling,a complete internal from may be milled in one operation.Gear wheels can be hob milled by carefully co-ordinating the rotational motions of both work and tool.For the production of slots and notches,from milling is applied.
When die sinking,the end mill can be moved in a two-dimensional mode and complicated internal shapes may be milled.On many milling machines,provision is made for drilling operations (drilling/milling centres)