Ba-Nr.: 930.50.02 E
Edition: 03/96
4.0 Working with the
gripping force meter
17 / 18
4.4.2 Example calculation
Power chuck type:
3 KTG 250
Max. actuating force Fax: 7000 daN
Jaw type:
hard top jaws
type
HB
12
Gripping diameter Dsp:
160 mm
Operating spindle speed n:
3000 rpm
Chuck constant C1:
909 mm
Chuck constant C2:
424 mm
Chuck constant C3:
0,4 kgm
Jaw overhang a:
45 mm
Number of jaws i:
3
How high is stationary gripping force Fspo ( n = 0 ), and how high is the gripping force
at spindle speed?
n = 3000 rpm
Dsp = 160 mm
Yab = 18,12 mm
Jaw weight G = 1,416 kg per jaw
Radius of centre of gravity of top jaws Ra
Ra
Dsp
Yab
mm
=
+
=
+
=
2
160
2
18,12
96,12
Total moment of top jaws Ma
Ma
Ra G i
kgm
=
=
=
1000
98 12 1 416 3
1000
0 417
,
,
,
Stationary gripping force ( n = 0 )
Fsp
C
C
a
Fax
0
1
2
=
+
Fsp
daN
kN
0
909
424
45
7000
13567
135 7
=
+
=
,
Dynamic gripping force at spindle speed n = 3000 rpm
(
)
(
)
Fsp
C
C
a
Fax
C
Ma
n
=
+
+
=
+
+
1
2
0 0008
3
909
424
45
7000
0 0008 0 4
0 417 3000
2
2
,
,
,
,
Fsp
daN
kN
=
=
13567
5882
7685
76 9
,
0
20
40
60
80
100
120
140
0
300
600
900
1200
1500
1800
2100
2400
2700
3000
n [1/min]
Fsp [kN]
Fsp0
Summary of Contents for SKM 1200
Page 19: ...Notes 1 19...
