Owner manual

19
f
n
h
ex
k
r
f
n
iC
Chip thickness
The chip thickness varies with round
inserts, and depends upon the entering
angle. With low a
p
/iC ratios, the feed can
be increased in order to raise the chip
thickness to a desired level.
Recommended chip thicknesses h
ex
for
HRSA are:
Carbide 0.1 to 0.35 mm
Ceramic 0.08 to 0.15 mm
Depth of cut to
diameter ratio
a
p
/iC
Depth of cut for insert diameter, in mm
Entering
angle k
r
Feed modi-
fication
value
Feed min/max
mm/r
h
ex
0.1
mm
h
ex
0.35
mm
6 mm diameter CoroCut RO insert.
Depth of cut 0.9 mm gives a maximum
entering angle k
r
= 46°.
To machine with:
Minimum 0.1 mm chip thickness the cor-
rect feed is 0.14 mm/r.
Maximum 0.35 mm chip thickness the
correct feed is 0.49 mm/r.
The surface finish generated has a direct
relationship to both the nose radius size
and the feed rate. To achieve a certain
surface finish, a small nose radius requires
a lower feed rate than a large nose radius
– which in practical terms means that small
nose radius inserts lead to lower productiv-
ity.
Therefore, for the highest productivity the
nose radius should be as large as possible
– the largest of all being round inserts.
Nose radius size mm Insert diameter mm
Maximum feed f
n
mm/r to achieve surface finish R
max
8.0 – R
a
1.6 µm – N7
Example
Surface finish
f
n
=
h
ex
sink
r
3 4 5 6 8 10 12 16
0.25 0.75 1 1.25 1.5 2 2.5 3 4 60° 1.16 0.12 0.41
0.2 0.6 0.8 1 1.2 1.6 2 2.4 3.2 53° 1.25 0.13 0.44
0.15 0.45 0.6 0.75 0.9 1.2 1.5 1.8 2.4 46° 1.4 0.14 0.49
0.1 0.3 0.4 0.5 0.6 0.8 1 1.2 1.6 37° 1.66 0.17 0.58
0.05 0.15 0.2 0.25 0.3 0.4 0.5 0.6 0.8 26° 2.3 0.23 0.81
0.4 0.8 1.2 1.6 8 10 12 16
0.17 0.22 0.27 0.32 0.5 0.57 0.62 0.7