Manitowoc National Crane NBT60L

2-10 Published 09-06-2019 Control # 691-01
SAFETY PRECAUTIONS NBT60L OPERATOR MANUAL
Calculation of Projected Wind Area (Ap):
Determining Wind Drag Coefficient (Cd)
Table 2-2 shows the typical Shapes and corresponding Wind
Drag Coefficient (Cd) values.
If the exact Wind Drag Coefficient of a shape is not known
,
use the maximum value of the shape’s range
(Table 2-2).
If the wind drag coefficient of the load cannot be estimated or
determined, it shall be assumed that (Cd)=2.4.
A
p
=24m
2
A
p
=8m
2
Wind
Wind
8m
1m
3m
8m
1m
3m
A
p
= 250 ft
2
A
p
=75ft
2
Wind
Wind
25 ft
3ft
10 ft
25 ft
3ft
10 ft
8384-1
FIGURE 2-2