l For a in particular in a particular turning operation the

l. For a in particular in a particular turning operation, the cost of the labor and machine time in resetting a cutting edge is $0.50, the cost of each throwaway insert having four cutting edges is $2.00, and the depreciation of the insert holder per insert is 8. The initial cost of the lathe was $30,000, which is amortized for 5 years. Machine running costs including labor and overhead but neglecting depreciation are estimated at $15.00/h.

Solution

1)taylors equation of tool life is

VT^n=C

for v=7.6 m/s and t=60 s

c=21.1519

2)total number of working hr for 40 hr.wk shift for 5 year is=5*40*50=10000 hr

3)where lathe depreciation per hr is given as

lathe depreciation cost=k1=30000/10000=3 dollar/hr

4)tool reseeting cost=K2=(2+.5+.08)*(number of tool failure per hr)

number oftool failure per hr=time/tool life=3600/60=60 tool

tool changing cost=K2=2.58*60=154.8 dollar/hr

5)operational cost=K3=15 dollar/hr

6)operating cutting speed for minimum cost is

Vo=C/((1/n-1)((K1+K2+K3)/K3))^n

Vo=8.7238 m/hr

7)tool life for minimum cost is

To=(C/Vo)^(1/n)=34.56 hr