
PROGRAMMING5. FEED FUNCTIONS
B–63514EN/01
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Feedrate of linear interpolation (G01), circular interpolation (G02, G03),
etc. are commanded with numbers after the F code.
In cutting feed, the next block is executed so that the feedrate change from
the previous block is minimized.
Three modes of specification are available:
1. Feed per minute (G94)
After F, specify the amount of feed of the tool per minute.
2. Feed per revolution (G95)
After F, specify the amount of feed of the tool per spindle revolution.
3. F1–digit feed
Specify a desired one–digit number after F. Then, the feedrate set with
the CNC for that number is set.
Feed per minute
G94 ; G code (group 05) for feed per minute
F_ ; Feedrate command (mm/min or inch/min)
Feed per revolution
G95 ; G code (group 05) for feed per revolution
F_ ; Feedrate command (mm/rev or inch/rev)
F1–digit feed
FN ;
N : Number from 1 to 9
Cutting feed is controlled so that the tangential feedrate is always set at
a specified feedrate.
X
End point
Starting
point
X
F
F
Center End point
Start
point
Linear interpolation
Circular interpolation
YY
Fig. 5.3 (a) Tangential feedrate (F)
After specifying G94 (in the feed per minute mode), the amount of feed
of the tool per minute is to be directly specified by setting a number after
F. G94 is a modal code. Once a G94 is specified, it is valid until G95 (feed
per revolution) is specified. At power–on, the feed per minute mode is
set.
An override from 0% to 254% (in 1% steps) can be applied to feed per
minute with the switch on the machine operator’s panel. For detailed
information, see the appropriate manual of the machine tool builder.
5.3
CUTTING FEED
Format
Explanations
D Tangential speed
constant control
D Feed per minute (G94)