Zoomlion RT75, Operator'S Manual

Page: 41 / 178

05 - 2
RT75 Rough Terrain Crane
To make an estimate of the wind speed, use the table that follows:
Wind force Wind speed
Effect of the wind on the land
Beaufort
scale
Description
m/s
ft-in
/
s
0 Calm 0 - 0.2
0 -
8″
No wind, smoke rises vertically
1 Light air 0.4 - 1.4
1
′-4″ - 4′-7″
Wind direction shown by smoke drift but
not by wind vanes
2
Light
breeze
1.6 - 3
Wind felt on face, leaves rustle, vanes
moved by wind
3
Gentle
breeze
3.4 - 5.3
5′-3″ - 9′-10″
Leaves and small twigs in constant
motion, wind extends light flag
4
Moderate
breeze
5.5 - 7.8 18
′-1″ - 25′-7″
Small branches move
5
Fresh
breeze
8 - 10.6
26
′-3″ - 34′-9″
Small trees in leaf begin to sway
6
Strong
wind
10.8 - 13.7 35
′-5″ - 45′-0″
Large branches in motion; difficult to use
umbrellas, whistling heard in telegraph
wires
7 Near gale 13.9 - 17 45
′-7″ - 55′-9″
Whole trees in motion, difficult to walk
against the wind
8 Gale 17.2 - 20.6 56
′-5″ - 67′-7″
Breaks twigs off trees, impedes progress
9 Strong gale 20.8 - 24.5
68′-3″ - 80′-5″
Slight structural damage (roof tiles and
chimney covers, etc. blown off)
10 Storm 24.7 - 28.3
81
′-0″ - 92′-10″
Trees uprooted, considerable damage
occurs
G. Do not operate the crane until it is in proper operating condition.
11
′-2″ - 17′-5″