Rockwell Automation 8520-GUM 9/Series CNC Grinder Operation and Programming Manual Documentation Set - Manual (Page 426)

Axis Motion
Chapter 12
12-54
Figure 12.26
Programmed Feedrate Executed along the Effective Axis Path
Z Z
X X
Linear interpolation Circular interpolation
programmed
feedrate
X-axis
feedrate
start
point
Z-axis
feedrate
end
point
programmed
feedrate
end point
X-axis
feedrate
start
point
Z-axis
feedrate
12158-I
For example, if a feedrate is programmed as F100.0 millimeters per minute
and a linear move is made from X0, Z0 to X10., Z10. the feedrate along
that 45 degree angular path would be 100.0 mmpm. The actual feed rate of
each axis is approximately 70.7 millimeters per minute.
When the grinding wheel is offset from a programmed path (as in the case
of dresser/wheel radius compensation), the programmed feedrate is applied
to the center of the wheel radius for all linear and outside arc paths.
For linear paths, the result is not significant because the speed of the wheel
surface relative to the part surface remains the same as the programmed
feedrate.
For outside arc paths, the resulting speed of the wheel surface relative to
the part surface is less than the programmed feedrate. This generally
causes no problem and so the control does not take corrective action.
For inside arc paths, the resulting speed of the wheel surface relative to the
part surface would be greater than the programmed feedrate. Since this
could cause excessive wheel loading and poor grinding performance, the
control automatically takes corrective action.
12.7.1
Feedrates Applied During
Dresser/Wheel Radius
Compensation