
102 Fundamentals of Machining Processes
machining time for a single component. According to Taylor for-
mula, the tool life T can be expressed by
T
C
n
=
When machining cylindrical components of length l and diameter d
using a feed rate S, mm/rev, and a rotational speed N, the machining
time t
m
becomes
m
=
m
=
where
=
The prime and sharpening cost/component, C
t1
, becomes
t
T
1
=
t
1
=
C
CV
n
t
T
/
1
1
=
ϑ
It is clear from the preceding equation that the increase of cutting
speed raises the tool prime and sharpening cost C
t1
.
2. Tool changing cost, C
t2
: The tool changing time, t
ct
, is the time ta ...