Sandvik Coromant Silent tools - users guide - Manual (Page 8)

8
2) )
F
t = kc0.4
u
0.4
f
n
0.29
u
f
n
ua
p
1) )
F
t = kc0.4
u
m
c
u
f
n
ua
p
0.4
f
n
u
sin
N
r
Calculation of boring bar load
The load on a boring bar is mainly dependent on the
depth of cut, the feed and the workpiece material.
Maximum load for each boring bar is listed on page
26-28 and marked on each tool.
For entering angle kr 75° or
longer, sin kr ≈ 1. Use the
simplified formula 2.
k
c0.4
; Specific cutting force at feed 0.4 mm/r. See Main
catalogue for k
c0.4
value.
m
c
; Constant, depending on the material. Use 0.29 as
general value.
A rule of thumb; F
t
should not exceed 90% of maximum
load stated for de bar used.
In turning, the tangential
force F
t
can be calculated
with formula 1.