Constant Cutting Rate (G96/G961/G962, G97/G971/G972, G973, Lims, Scc[Ax]) - Siemens SINUMERIK 840Di sl Programming Manual

Feedrate Control and Spindle Motion

7.11 Constant cutting rate (G96/G961/G962, G97/G971/G972, G973, LIMS, SCC[AX])

7.11 Constant cutting rate (G96/G961/G962, G97/G971/G972, G973, LIMS,
SCC[AX])
Function
When G96/G961 is active, the spindle speed – depending on the respective workpiece
diameter – is modified in order that the cutting rate S in m/min or ft/min remains constant at
the tool edge.
This increases the uniformity and thus the surface quality of turned parts, and also protects
the tool.
The constant cutting rate, activated with G96/G961/G962 can be cancelled again with
G97/G971/G972 with the active feed type (G94 linear feed or G95 revolutional feedrate).
Using G973 a constant cutting rate (G96) is de-selected without speed limiting being
activated as is the case for G97.
If any of the G96/G961/G962 functions are active, SCC[axis] can be used to assign any
geometry axis as a reference axis. If the reference axis changes, which will in turn affect the
TCP (tool-center-point) reference position for the constant cutting rate, the resulting spindle
speed will be attained via the set braking or acceleration ramp.
The command LIMS specifies a maximum spindle speed limitation for the master spindle.
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Programming Manual, 11/2006, 6FC5398-1BP10-2BA0
Fundamentals