Rockwell Automation 8520 9/Series CNC Lathe - Manual (Page 545)

Single-Pass Turning Cycles
Chapter 22
22-5
G20 Taper O.D. and I.D. Roughing
A G20 block that includes an I-word generates a turning pass that produces
a taper.
Figure 22.3
G20 Taper Cutting Cycle
Cutting feed
Rapid feed
I
Z
X
The format for the G20 single-pass cycle to cut a taper is:
G20X__Z__I__;
Where : Is :
X__ the depth of cut for the X axis at the end point of the cutting move into the part.
In incremental mode specify the amount of infeed, in absolute mode specify the
coordinate position at the desired depth of cut. X may be programmed as either
a diameter or radius value.
Z__ the length of cut along the Z axis. In incremental mode specify the amount of
feed across the part, in absolute mode specify the coordinate position of the end
point of the cutting stroke.
I__ the amount of change in the depth of cut for the X axis. I is always an
incremental radius value. Figure 22.4 shows the relationship between the sign of
the I value and the way that the cycle is performed. The control adds the value
of I to the X depth to determine the start point of the cutting pass.