HEIDENHAIN TNC 320 User Manual page 107

Cycle parameters
U
Nominal diameter Q335: Nominal thread diameter.
Input range 0 to 99999.9999
U Thread pitch Q239: Pitch of the thread. The algebraic
sign differentiates between right-hand and left-hand
threads:
+= right-hand thread
– = left-hand thread
Input range -99.9999 to 99.9999
U
Thread depth Q201 (incremental): Distance between
workpiece surface and root of thread. Input range
-99999.9999 to 99999.9999
U Threads per step Q355: Number of thread
revolutions by which the tool is moved:
0 = one 360° helical line to the thread depth
1 = continuous helical path over the entire length of
the thread
>1 = several helical paths with approach and
departure; between them, the TNC offsets the tool by
Q355, multiplied by the pitch. Input range 0 to 99999
U Feed rate for pre-positioning Q253: Traversing
speed of the tool in mm/min when plunging into the
workpiece, or when retracting from the workpiece.
Input range 0 to 99999.999; alternatively FMAX,
FAUTO
U Climb or up-cut Q351: Type of milling operation with
M3
+1 = climb milling
–1 = up-cut milling
U Set-up clearance Q200 (incremental): Distance
between tool tip and workpiece surface. Input range
0 to 99999.9999
U
Workpiece surface coordinate Q203 (absolute):
Coordinate of the workpiece surface. Input range
-99999.9999 to 99999.9999
U 2nd set-up clearance Q204 (incremental): Coordinate
in the spindle axis at which no collision between tool
and workpiece (fixtures) can occur. Input range 0 to
99999.9999
U
Feed rate for milling Q207: Traversing speed of the
tool during milling in mm/min. Input range 0 to
99999.999; alternatively FAUTO
HEIDENHAIN TNC 320
Example: NC blocks
25 CYCL DEF 262 THREAD MILLING
Q335=10 ;NOMINAL DIAMETER
Q239=+1.5 ;PITCH
Q201=-20 ;DEPTH OF THREAD
Q355=0 ;THREADS PER STEP
Q253=750 ;F PRE-POSITIONING
Q351=+1 ;CLIMB OR UP-CUT
Q200=2 ;SET-UP CLEARANCE
Q203=+30 ;SURFACE COORDINATE
Q204=50 ;2ND SET-UP CLEARANCE
Q207=500 ;FEED RATE FOR MILLING
107