L 2.1 Cutting Speed

Cutting speed of a cutting tool can be defined as the rate at which its cutting edge passes over the surface of the workpiece in unit time. it is normally expressed in terms of surface speed in metre per minute. selection of proper cutting speed is very important. 

  • if it is too high, the tool gets overheated and its cutting edge may fail. 

  • if it too low, too much time is consumed in machining and a full cutting capacity of the tool and machine are not utilise, which result in lowering of productivity and increasing the production cost. 

 

Fig. 2.1 Showing Speed, feed and DOC 

Cutting speed (V) = πDN/1000 m/min 

Where D = diameter of the workpiece (mm) 

N = rpm of the work 

Cutting speed depends upon the following factors: 

  • Tool material. 

  • Work material. 

  • Depth of cut. 

  • Tool geometry. 

  • Type of machine tool. 

  • Surface quality required.