COMEUP Electric Winch (Ver:02) - Manual (Page 8)

6
Calculating Fleet Angle
● The winch should be mounted as close to centre
and as perpendicular as possible to the direction
of the line pull. This will keep the wire rope fleet
angle centre on the drum as small as possible.
● If the proper fleet angle is not maintained, the wire
rope could wind onto one side of the drum.
Experience has shown that the best wire rope service is obtained if the maximum fleet angle
is not more than 1.5° for smooth drum and 2° for grooved drum.
For example, the correct distance varies according to drum length.
D/d Ratio
It means ratio of pitch circle diameter of drum to the rope diameter.
In principle, a 12:1 D/d ratio is suggested for most pulling application and a 15:1 D/d ratio for
lifting and lowering applications. For example, a CP-200 comes with a 94 mm dia. drum and
a 6 mm x 30 m wire rope, therefore its D/d ratio is calculated as follow.
D/d ratio = ( 94 + 6 mm ) / 6 mm = 16.67 times
Rope Safety Factor
The working coefficient of the wire rope shall be determined from the ratio of the minimum
breaking force of the rope and the maximum possible lifting capacity.
In principle, a 3.5 times of rope safety factor is suitable for most pulling applications and a 5
times for lifting and lowering applications. For example, a CP-200 comes with a 6 mm x 30 m
wire rope with 2,010 kg minimum breaking force, therefore its rope safety factor is calculated
as follow.
Rope safety factor = 2,010 kg / 200 kg = 10 times
θ
θ
Correct Distance
Drum Length
Fleet Angle
Model
CP-200/250/300,
CWG-30075
CP-500/500T CWG-10077
CWG-10151/30151,
CP-750T/900T
Drum Length 110 mm 220mm 150 mm 240 mm
Correct
Distance
2.09 m
at least
4.18 m
at least
2.85 m
at least
4.56 m
at least
Model CWG-30375 CWG-30565 CWG-30750 CWG-31500 CWG-34000
Drum Length 230 mm 312 mm 312 mm 405 mm 680 mm
Correct
Distance
2.09 m
at least
5.92 m
at least
5.92 m
at least
7.7 m
at least
12.92 m
at least