
2-19
CD25
SAFETY INFORMATION
2
Published 1-06-2017 Control # 579-01
Example, wind speeds greater than 13.4 m/s is NOT
permissible to lift a load greater than 20,160 lb, even if the
wind resistance area of the load is less than 119 ft
2
.
Refer to the above crane configuration for the following load
conditions:
Load example 2.1:
With known Wind Drag Coefficient of the load
Cd
,
•
load to be lifted of 19,500 lb,
•
Projected Wind Area
Ap
= 70 ft
2
,
•
Wind Drag Coefficient
Cd
= 1.5
then the wind resistance area of load can be estimated as
Awr
(load)
=
Ap
x
Cd
=
70 x 1.5 = 105 ft
2
Refer to the above
Lifting
Limits at wind speed V(z) > 30
mph and
≤
45 mph
. Comparing the load and wind resistant
area to the allowable:
•
Is the load to be lifted less than allowable load?
19,500 lb
≤
20,160 lb
YES
•
Is
Awr
(
load)
less than
Awr
(allow)
?
105 ft
2
≤
119 ft
2
YES
Conclusion
: This load is permissible to lift in wind speed up
to 45 mph.
Load example 2.2:
With unknown Wind Drag Coefficient of the load
Cd
,
•
Load to be lifted of 18,000 lb,
•
Projected Wind Area
Ap
= 45 ft
2
,
•
Wind Drag Coefficient
Cd
= unknown
NOTE:
If exact Wind Drag Coefficient is not known, it shall
be assumed as 2.4.
the wind resistance area of load can be estimated as
Awr
(load)
=
Ap
x
Cd
=
45 x 2.4 = 108 ft
2
Refer to the above
Lifting Limits at wind speed V(z)
> 30 mph and
≤
45 mph
. Comparing the load and wind
resistant area to the allowable:
•
Is the load to be lifted less than allowable load?
18,000 lb
≤
20,160 lb
YES
•
Is
Awr
(load)
less than
Awr
(allow)
?
108 ft
2
≤
119 ft
2
YES
Conclusion
: This load is permissible to lift in wind speed up
to 45 mph.
Load example 2.3a:
With large wind resistance area of the load
Awr
(load)
,
•
Load to be lifted of 22,000 lb,
•
Projected Wind Area
Ap
= 180 ft
2
,
•
Wind Drag Coefficient
Cd
= 1.2
the wind resistance area of load can be estimated as:
Awr
(load)
=
Ap
x
Cd
=
180 x 1.2 = 216 ft
2
Refer to the above
Lifting Limits at wind speed V(z) >
30 mph and
≤
45 mph
. Comparing the load to the allowable:
•
Is the load to be lifted less than allowable load?
22,000 lb
≤
20,160 lb
NO
Conclusion
: This load is NOT permissible to lift in wind
speed up to 45 mph.
Refer to the above
Lifting Limits at wind speed V(z) up to
30 mph
. Comparing the load to the allowable:
Is the load to be lifted less than allowable load?
22,000 lb
≤
25,200 lb . . . . . . . . . . . . . . . . . . . . YES
The permissible wind speed for this load is 30 mph,
depending on the wind resistance area of the load.
•
Is
Awr
(load)
less than
Awr
(allow)
,?
216 ft
2
≤
149 ft
2
. . . . . . . . . . . . . . . . . . . . . . . . . NO
Conclusion
: This load is NOT permissible to lift in wind
speed at 30 mph, but permitted to lift at a reduced wind
speed calculated as follows:
Ratio =
1.45
From Table 2-7, the maximum permissible wind speed at
ratio of 1.45 (rounded to next higher table value of 1.6) is
23.7 mph.
Conclusion
: This load is permissible to lift in wind speed up
to 23.7 mph only.
Load example 2.3b:
With large wind resistance area of the load
Awr
(load),
•
Load to be lifted of 12,000 lb,
•
Projected Wind Area
Ap
= 125 ft
2
,
•
Wind Drag Coefficient
Cd
= 1.3
the wind resistance area of load can be estimated as:
Awr
(load)
=
Ap
x
Cd
= 125 x 1.3 = 162 ft
2
L i f t i n g L i m i t s a t w i n d s p e e d V ( z ) >
3 0 m p h
and
≤
45 mph
at this configuration:
•
Maximum load 20,160 lb
•
Maximum wind resistance area of load 119 ft
2
Reference Only
Содержание CD25
Страница 5: ...Operator Manual CD25 R e f e r e n c e O n l y ...
Страница 6: ...R e f e r e n c e O n l y ...
Страница 14: ...TABLE OF CONTENTS CD25 OPERATOR MANUAL TOC 6 THIS PAGE BLANK R e f e r e n c e O n l y ...
Страница 18: ...INTRODUCTION CD25 1 4 Published 1 06 2017 Control 579 01 THIS PAGE BLANK R e f e r e n c e O n l y ...
Страница 55: ...2 37 CD25 SAFETY INFORMATION 2 Published 1 06 2017 Control 579 01 8496 1 FIGURE 2 10 R e f e r e n c e O n l y ...
Страница 66: ...SAFETY INFORMATION CD25 2 48 Published 1 06 2017 Control 579 01 2 48 THIS PAGE BLANK R e f e r e n c e O n l y ...
Страница 100: ...CAPACITY CHART CD25 4 4 Published 1 06 2017 Control 579 01 THIS PAGE BLANK R e f e r e n c e O n l y ...
Страница 150: ...MAINTENANCE CD25 6 40 Published 1 06 2017 Control 579 01 THIS PAGE BLANK R e f e r e n c e O n l y ...
Страница 152: ...ADJUSTMENTS CD25 7 2 Published 1 06 2017 Control 579 01 THIS PAGE BLANK R e f e r e n c e O n l y ...
Страница 156: ...8 4 SPECIFICATIONS CD25 Published 1 06 2017 Control 579 01 Boom angle Maximum 80 Minimum 0 R e f e r e n c e O n l y ...
Страница 159: ...R e f e r e n c e O n l y ...
Страница 160: ...R e f e r e n c e O n l y ...