A batch of 500 jobs of diameter 50mm and length 100mm is to be turned at 200rev/min and feed 0.2mm/rev The number of tool changes required to machine the whole batch is
Bars of 250mm length and 25mm diameter are to be turned on a lathe with a feed of 0.2mm/rev. Each regrinding of the tool costs is Rs.20.The time required for each tool chnage is 1 min. Tool life equation is given as VT02=24 (where cutting speed V is in /(m/min\) and tool life T is in min). The optimum tool cost per piece for maximum production rate is Rs (round off to 2 decimal places).
Linked Question A low carbon steel bar of 147mm diameter with a length of 630mm is being turned with an uncoated carbide insert. The observed tool lives are 24min and 12min for cutting velocities of 90m/min and 120m/min respectively. The feed and depth of cut are 0.2mm/rev and 2mm respectively. Use the unmachined diameter to calculate the cutting velocity. Neglect over-travel or approach of the tool. When too life is 20min, the machining time in min for a single pass is