
10
6461
2
2022
-
SPS-B
MC_0207
Hull Forces
All calculated values are normalised, determined by equilibrium considerations and also that various coeffi cients are inaccurate as hull design etc will
affect the actual fi n effect.
Dynamic effects such as jumps/impacts with waves, back flow closing of valve etc could further increase the hull/shaft loads. Therefore all
dimensioning should account for this by using a safety factor.
The aft top face of the fi n is deliberately made weaker than the rest of the fi n so it will break easier in case of an impact with the hull.
It is advised to strengthen the hull or ensure it is manufactured with materials suitable to sustaining impacts over the total length of the fi n within an
area of approximately 10 degrees of fi n rotation in each direction from its centre.
(NB: This is a safety measure to ensure the fi n will not break through the hull in a collision situation.)
Sleipner curved Vector Fin design comes with additional benefi ts in hull safety. Any impact with the ground will not only bend the shaft backwards and
outward, allowing the fi n to break away with less stress on the hull.
MG_0284
Bending moment
(Mx and My
components)
Shear force
(FX and Fy
components)
Axial shaft
force (fz)
Torque
moment (Mz)
Outer surface
hull
MC_0253
Fin Loads on Hull
Fin size
Speed
Bending
moment
(Mx+My)
Twisting
torque
(Mz)
Axial
shaft
(Fz)
Shear
force
(Fx+Fy)
Shaft
breakaway
SPS66/67
VF1050
10 kn
5500 Nm
3400 Nm
5000 N
10200 N
350 kN
15 kn
6500 Nm
3400 Nm
6000 N
11200 N
350 kN
20 kn
8200 Nm
3400 Nm
7300 N
12200 N
350 kN
25 kn
9600 Nm
3400 Nm
8600 N
14200 N
350 kN
30 kn
10000 Nm
3400 Nm
9000 N
15500 N
350 kN
35 kn
10000 Nm
3400 Nm
9000 N
23300 N
350 kN
40 kn
10000 Nm
3400 Nm
9000 N
23300 N
350 kN
SPS92
VF1350
10 kn /
Min
10500 Nm
7000 Nm
6500 N
19000 N
940 kN
15 kn
12500 Nm
7000 Nm
10000 N
20000 N
940 kN
20 kn
15000 Nm
7000 Nm
12000 N
21000 N
940 kN
25 kn
17500 Nm
7000 Nm
13700 N
22500 N
940 kN
30 kn
18000 Nm
7000 Nm
14600 N
27500 N
940 kN
35 kn
18000 Nm
7000 Nm
14600 N
35000 N
940 kN
40 kn
18000 Nm
7000 Nm
14600 N
35000 N
940 kN
SPS93
VF1650
10 kn /
Min
11500 Nm
7000 Nm
8000 N
18000 N
940 kN
15 kn
13500 Nm
7000 Nm
10500 N
19000 N
940 kN
20 kn
17500 Nm
7000 Nm
12500 N
21000 N
940 kN
25 kn
20000 Nm
7000 Nm
14500 N
23000 N
940 kN
30 kn
20500 Nm
7000 Nm
15000 N
28000 N
940 kN
35 kn
20500 Nm
7000 Nm
15000 N
38000 N
940 kN
40 kn
20500 Nm
7000 Nm
15000 N
38000 N
940 kN
Fin size
Speed
Bending
moment
(Mx+My)
Twisting
torque
(Mz)
Axial
shaft
(Fz)
Shear
force
(Fx+Fy)
Shaft
breakaway
SPS95B
VFS1950
22%
SHAFT
POSI-
TION
10 kn /
Min
7800 Nm
7800 Nm
3800 N
18000 N
940 kN
15 kn
12600 Nm
7800 Nm
8500 N
31000 N
940 kN
20 kn
14600 Nm
7800 Nm
10600 N
34000 N
940 kN
25 kn
15100 Nm
7800 Nm
16500 N
37000 N
940 kN
30 kn
17000 Nm
7800 Nm
18200 N
41500 N
940 kN
35 kn
18350 Nm
7800 Nm
24800 N
43500 N
940 kN
40 kn
20000 Nm
7800 Nm
32000 N
47000 N
940 kN
SPS95B
VFS1950
26%
SHAFT
POSI-
TION
10 kn /
Min
7600 Nm
7800 Nm
3800 N
18000 N
940 kN
15 kn
16000 Nm
7800 Nm
8500 N
40000 N
940 kN
20 kn
19600 Nm
7800 Nm
10600 N
49000 N
940 kN
25 kn
20200 Nm
7800 Nm
16500 N
50488 N
940 kN
30 kn
22700 Nm
7800 Nm
18200 N
57000 N
940 kN
35 kn
24300 Nm
7800 Nm
24800 N
60000 N
940 kN
40 kn
26300 Nm
7800 Nm
32000 N
64200 N
940 kN
SPS95B
VFS1950
30%
SHAFT
POSI-
TION
10 kn /
Min
7500 Nm
7800 Nm
3800 N
18000 N
940 kN
15 kn
17000 Nm
7800 Nm
8500 N
40000 N
940 kN
20 kn
28600 Nm
7800 Nm
10600 N
64000 N
940 kN
25 kn
31700 Nm
7800 Nm
16500 N
81000 N
940 kN
30 kn
35900 Nm
7800 Nm
18200 N
92000 N
940 kN
35 kn
38200 Nm
7800 Nm
24800 N
99000 N
940 kN
40 kn
41100 Nm
7800 Nm
32000 N
105000 N
940 kN
Maximum 30 knots top speed for SPS55 / VF1050 combination