SIEMENS
FLENDER Standard Couplings
Highly Flexible Couplings — ELPEX-S Series
11/7
Siemens MD 10.1 · 2015
General information
11
Torsional stiffness
The dynamic torsional stiffness of the silicone rubber elements is
load-dependent and increases in proportion to the load. The val-
ues specified in the selection table represent 100 % loading.
The following table shows the correction factors for different
rated loads.
C
Tdyn
=
C
Tdyn 100 %
⋅
FKC
Damping coefficient of the rubber versions
Torsional stiffness also depends on the ambient temperature
and the frequency and amplitude of the torsional vibration exci-
tation. More precise torsional stiffness and damping parameters
on request.
With elastic couplings the manufacturing process of the rubber
elements and their aging primarily influence the rigidity value
C
Tdyn
. For this reason calculation must be made with a tolerance
for the dynamic rigidity of
±
20 %. The specified damping coeffi-
cient
Ψ
is a minimum value with the result that the damping per-
formance of the coupling corresponds at least to the specified
value.
For fitting, a maximum gap dimension of S max. = S +
Δ
S and a
minimum gap dimension of S min. = S –
Δ
S are permitted.
Permitted shaft misalignment
The permitted shaft misalignment depends on the operating
speed. As the speed increases, lower shaft misalignment values
are permitted. The following table shows the correction factors
for different speeds.
The maximum speed for the respective coupling size and type
must be noted!
Δ
K
perm
=
Δ
K
1500
⋅
FKV
Rubber disk elements made of silicone rubber
Type
Size
Rubber
version
Rated
torque
Maximum
torque
Overload
torque
Fatigue
torque
Dynamic torsional
stiffness for 100 %
load
T
KN
T
Kmax
T
KOL
T
KW
(10 Hz)
C
Tdyn
Nm
Nm
Nm
Nm
kNm/rad
ESN .
220
NX
200
300
400
87
1.70
ESN .
265
NX
300
450
600
133
3.10
ESN .
290
NX
500
750
1000
213
5.40
ESN .
320
NX
770
1150
1530
320
12.0
ESN .
360
NX
1200
1800
2400
480
12.7
ESN .
420
NX
2000
3000
4000
800
30.0
ESN .
465
NX
3000
4500
6000
1200
53.0
ESN .
520
NX
4100
6100
8200
1600
75.0
ESD .
520
NX
8200
12300
16400
3200
150
ESN .
560
NX
5000
7500
10000
2200
83
ESD .
560
NX
10000
15000
20000
4400
166
ESN .
580
NX
6500
9750
13000
2667
113
ESD .
580
NX
13000
19500
26000
5867
226
ESN .
680
NX
10000
15000
20000
4000
225
ESD .
680
NX
20000
30000
40000
8000
450
ESN .
770
NX
15000
22500
30000
6000
480
ESD .
770
NX
30000
45000
60000
12000
960
Rubber version
Hardness
Damping coefficient
ShoreA
ψ
WN
50° … 55°
0.80
NN
60° … 65°
1.15
SN
70° … 75°
1.25
NX
55° … 65°
1.15
Load
T
N
/
T
KN
20 %
50 %
60 %
70 %
80 %
100 %
150 %
Correction factor
FKC
0.42
0.57
0.64
0.72
0.8
1
1.6
Size
Assembly
Permitted shaft misalignment at
n
= 1500 rpm
Axial
Radial
Angle
Δ
S
Δ
K
a
Δ
K
r
Δ
K
w
mm
mm
mm
degrees
220
1.3
0.2
1.2
0.5
265
1.3
0.2
1.2
0.5
290
1.5
0.2
1.2
0.5
320
1.5
0.2
1.2
0.5
360
1.5
0.2
1.2
0.5
420
1.5
0.3
1.3
0.4
465
1.7
0.3
1.3
0.4
520
1.7
0.3
1.4
0.4
560
1.7
0.3
1.4
0.4
580
1.8
0.4
1.5
0.3
680
1.8
0.4
1.5
0.3
770
2.0
0.5
1.5
0.3
Speed in rpm
500
1000
1500
3000
Correction factor FKV
1.2
1.1
1.0
0.7
© Siemens AG 2015