Thread Interpolation: G331, G332 - Siemens sinumerik 808d Programming And Operating Manual

Programming principles
1.3 Axis movements
1.3.10

Thread interpolation: G331, G332

Functionality
A position-controlled spindle with position measuring system is required.
With G331/G332, threads without compensating chuck can be drilled, if the dynamic
response of the spindle and the axis allow this.
If a compensating chuck is used nevertheless, the position differences to be compensated
for by the compensating chuck are reduced. This allows thread grinding at higher spindle
speeds.
G331 applies for grinding, G332 for grinding in opposite direction.
The grinding depth is specified through the axis, e.g. Z; the thread lead through the
corresponding interpolation parameter (here: K).
For G332, the same lead is programmed as for G331. The spindle direction of rotation is
automatically reversed.
The spindle speed is programmed with S; without M3/M4.
Before thread grinding with G331/G332, the spindle must be brought into the closed-loop
position controlled mode using SPOS=... .
Right-hand or left-hand thread
The sign of the thread lead determines the direction of spindle rotation:
positive: right-hand (as with M3)
Negative: Left-hand (as with M4)
Axis velocity
For G331/G332, the velocity of the axis for the thread length results from the spindle speed
and the thread lead. The feedrate F is not relevant. It is, however, stored. However, the
maximum axis velocity (rapid traverse) defined in the machine data can not be exceeded.
This will result in an alarm.
Programming example
Metric thread 5,
lead according to the table: 0.8 mm/rev., hole already premachined:
N10 G54 G0 G90 X10 Z5
N20 SPOS=0
N30 G331 Z-25 K0.8 S600
N40 G332 Z5 K0.8
N50 G0 X10 Z5
N60 M30
48
; Approach starting point
;Spindle in position control
; Thread grinding, K positive = Clockwise rotation of
spindle, end point -25 mm
; Retraction
Turning Part 2: Programming (Siemens instructions)
Programming and Operating Manual, 05/2012, 6FC5398-5DP10-0BA0