Renishaw RCU10, Installation And User Manual, Page: 179 / 202

G-4 Reference
Workpiece thermal expansion compensation (µm) = ( AP
c
- AP
wce
- WO) .

w
. (20 - T
wc
)
This is the compensation for the linear thermal expansion of the workpiece in µm. It
includes the facility to provide additional compensation if the workpiece expansion origin is
not coincident with the point at which workpiece expansion compensation was enabled.
AP
c
= Current axis position (in m).
AP
wce
= Axis position (in m) at the instant workpiece compensation was enabled.
WO = Expected distance between the workpiece expansion origin and the cutting
tool tip (or processing point), when workpiece expansion compensation is
going to be enabled.
WO is measured parallel to the axis of motion and expressed in metres. WO
should be entered as a
negative value if the axis would have to travel in a
negative (reverse) direction to move the tool tip, from the point at which
workpiece compensation is enabled, to the workpiece expansion origin.
If the cutting tool tip is going to be positioned at the workpiece expansion origin
when workpiece expansion compensation is enabled, then WO should be set
to zero.

w
= Workpiece’s linear coefficient of thermal expansion (in µm/m/°C).
T
wc
= Current workpiece temperature (in °C).