Sandvik Coromant Silent tools - users guide - Manual (Page 25)

25
M = g
u
((mbar × COGbar) + (mhead
u
COGhead))
Moment calculation
When using Silent Tools bars in machines with automatic tool
change (ATC) it is important to control that the moment given
by the tool is within the specification that can be found on the
machine or in the machine documentation.
For a bar with cutting
head mounted, the
moment M can be
calculated as:
m
bar
/m
head
= the weight of the bar and the head respectively
During tool change the tool acceleration will give an extra
addition to the forces. It is strongly recommended to slow
down the tool changing process if the tool weight or moment
is close to the machine limits or consider performing a manual
tool change.
Example:
Bar: C6-SL3C32352-CR
Weight of bar, m
bar
: 3.5 kg
COG
bar
: 0.15 m
Weight of head, m
head
:
≈
0.3 kg
COG
head
≈
Length of bar, l
1
: 0.352 m
M = 9.8
u
((3.5 × 0.15) + (0.3
u
0.352)) ≈ 6.2 Nm
Note. Even if the weight
of the head is small,
the additional moment
is not negligible due to
the long overhang.
CoroTurn SL dia. 16-60 mm ≈0.3 kg
CoroTurn SL-QC ≈0.5 kg
For long boring bars, COG
head
≈ length of the bar l
1
COG = centre of gravity
g = the gravity constance (
≈
9,8)
For cutting heads: Use m
head
:
COGbar
COGhead