These equations help you evaluate your shop's performance in terms of production rate and costs/part.
Once modeled, they permit you to quickly determine the effects of changes in your machining operations. The well-known Taylor equation, V X t" = c produces a straight-line relationship between the log of cutting speed and the log of tool life. The exponent n is a non~varying constant, and quantifies the way tool wear changes as cutting speed changes. On the other hand, the taylor equation intercept c changes as real-world machining conditions change.

For a turning operation, production rate maximum speed is:
vprmax=exp[n X in{n/((1-n) X tc)}] X c
vprmax= speed for maximum production rate in surface feel/min
n= exponent of the taylor equation for speed versus tool life
c= Taylor equation intercept ( speed for one minute of tool life )
tc= tool change time in minutes

Minimum cost speed is calculated from the following formula
vlocost= exp[n X in{(n X burden/60)/((1-n) X (burden/60 X tc + ct))}] X c
vlocost= speed for minimum machining cost
burden= overhead rate ( dollars/hour )
ct= tool cost ( dollars/edge )

At any cutting production speed, you can calculate production rate as follows:
pr= pe/tt X 60
pr= production rate ( parts/hour )
pe= tool life ( parts/edge ) =tl/mt
tl= tool life from the taylor equation ( min/edge )
mt= machining time ( min/part )
pc= part change time ( min/part )
idletime= noncutting time for each machining cycle ( min/part )
tt= cutting edge total time ( min/edge )=tl + tc + (pc + idletime) X pe

Machining cost, at any speed, becomes:
mcost= cr/pr X 60
mcost= machining cost in dollars/part
cr= cost rate ( dollars/minute ) = ( burden/60 ) + ( ct/tt )

These relations apply directly to turning, and can be adapted to other types of machining operations.

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