INCLINING EXPERIMENT RESULTS:
26 m TRAWLER
By Mazlan Muslim, BSc, MEng
UniKL MIMET
Owner : Asas Ombak Sdn Bhd
[Koperasi Pembangunan Rakyat Pahang Berhad for new
vessels]
Type : Trawler
GRT : + 95 (Based on Fisheries Dept. Rules)
LOA : 27.0 m
LBP : 23.8 m
B mld : 6.00 m
D mld : 2.5 m
T designed : 1.9 m
Freeboard Summer : 0.60 m
Gearbox Ratio : 7.5:1
Classification : China Classification Society
Main Engine : Cummins KTA 19-M3 500 hp
Auxiliary Engine : 250 hp
Generating Set : Cummins 50 kW x 1
V Trawl : Up to 5 knots
V Design : Up to 12 knots
: 171 MT
RECORD OF INCLINING TEST
Port : MSB (Majuikan Sdn Bhd) Complex, Kuantan, Pahang
Wind : Light Breeze
Water : Calm
S.g. of Water : 1.02 t/m3
T Aft : 2.45 m
T Fwd : 1.49 m
T Mean : 1.97 m
Shift of Inclining Wts. : 4.80 m
No. of Move Weight Moved (T) Direction Pendulum Deflection (deg.)
1 0.70 Port-Stbd 0.85
2 1.40 Port-Stbd 1.46
3 - Stbd-Port 0
4 0.70 Stbd-Port 1.26
5 1.40 Stbd-Port 1.34
6 - Port-Stbd 0
The average inclining in deg. was obtained for a movement of w (i.e. 0.7 T) through 4.8m. As w is moved across the deck the CG of the ship moves from G to G1 such that
Wh = x GG1
where
= Displacement of vessel in T
The centre of buoyancy B was originally under G, but it will move to B1 to be in the same vertical line as G1.
GG1 is parallel to the movement of w and since
Angle MGG1 = 900
GG1 = GM tan
Therefore wh = GM tan
GM = wh/ tan
= (0.7 x 4.8)/(166.03 x tan1.260)
= 0.92 m
SOUNDING & QUANTITIES
Tank No. Type of Tanks Quantity (T)
1 Fresh Water (FW) 8.00
2 Fuel Oil (FO) 2.67
FW Tanks : 5.4 m x 1.0 m Athwartships
FO Tanks : 6.0 m x 3.5 m Athwartships
After the value of GM had been calculated for the ship in the inclined condition a correction may be made for the presence of free surfaces in double-bottom or other tanks. The presence of free surfaces – the value of GM by an amount:
GG1 = (I x i)/( x s)
where
GG1 = the amount by which the CG of the ship is raised due to the presence of
each free surface;
i.e. the amount by which GM is reduced since M (metacentre) is constant.
I = the transverse moment of inertia of the free surface about its own centre
line;
= Vol. of disp. of ship;
i = density of liquid with free surface;
s = density of water in which the ship floats.
LIGHTSHIP FROM RESULTS OF INCLINING TEST
Item Tonnes VCG (m) Vert. Mom. (T.m) LCG (m) Moment (T.m)
Aft
Fwd
To come off:
Inclining weights 2.80 3.00 8.4 0.7 Aft 1.96
FW Tanks 8.00 1.60 12.8 6.6 Fwd 52.8
FO Tanks 2.67 0.23 0.614 0.37 Fwd 0.99
Men, tools, gear, staging 0.50 3.30 1.65 2.00 Aft 1.00
Total Off 13.97 23.46
As inclined 180.0
Lightship 166.03
T mean (1.97 m)
Centre of flotation
Free surface correction 0.114 m
T Fwd 1.49 m
T Aft 2.45 m
Attributes of the Prophet Muhammad SAW Praise be to Allah, the Lord of Creations, and Peace and blessings be upon our prophet Muhammad, the faithful and the honest. Oh, Allah, we know nothing but what You teach us. You are the All- Knower, the Wise. Oh Allah, teach us what is good for us, and benefit us from what You taught us, and increase our knowledge. Show us the righteous things as righteous and help us to do them, and show us the bad things as bad and help us to keep away from them. O Allah our Lord, lead us out from the depths of darkness and illusion, unto the lights of erudition and knowledge, and from the muddy shallows of lusts unto the heavens of Your Vicinity. Dear brothers, this is the first part of the introduction to our new series: “Ways of access and signs of acceptance”, inspired by Allah’s Words: "I am only a man like you. It has been inspired to me." [Al Kahf, 110] It is as if in this ayah Allah the ...
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