Cycle parameters – HEIDENHAIN iTNC 530 (34049x-08) Cycle programming User Manual
Page 123

HEIDENHAIN iTNC 530
123
4.6 THREAD MILLING (Cy
cle
262, DIN/ISO:
G262)
Cycle parameters
Nominal diameter
Q335: Nominal thread diameter.
Input range 0 to 99999.9999
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
Thread depth
Q201 (incremental): Distance between
workpiece surface and root of thread. Input range
-99999.9999 to 99999.9999
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
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,
PREDEF
Climb or up-cut
Q351: Type of milling operation with
M3
+1
= climb milling
–1
= up-cut milling
Alternatively PREDEF
Set-up clearance
Q200 (incremental): Distance
between tool tip and workpiece surface. Input range
0 to 99999.9999; alternatively PREDEF
Workpiece surface coordinate
Q203 (absolute):
Coordinate of the workpiece surface. Input range
-99999.9999 to 99999.9999
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; alternatively PREDEF
Feed rate for milling
Q207: Traversing speed of the
tool during milling in mm/min. Input range 0 to
99999.999; alternatively FAUTO
Feed rate for approach
Q512: Traversing speed of
the tool during entry into the thread in mm/min. Input
range 0 to 99999.999; alternatively FAUTO
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
Q512=50
;FEED RATE FOR APPROACH
X
Z
Q203
Q253
Q239
Q201
Q204
Q200
Q355 = 1
Q355 > 1
Q355 = 0