This document provides information on cranes and crane safety. It begins with objectives of becoming familiar with common crane types, rigging, and controlling hazards. It then outlines and describes industrial cranes like overhead, gantry, and jib cranes and construction cranes like mobile, tower, and derrick cranes. It discusses rigging components and the importance of sling angle. The document also covers controlling hazards through inspections, training, preventing power line contact, ensuring crane stability, and following load charts. It provides statistics on crane accidents and their leading causes.

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2. Objectives
 Know hazards associated with cranes
 Become familiar with common types of industrial and
construction cranes
 Understand rigging basics, including the importance
of “sling angle”
 Be familiar with methods of controlling crane hazards
and preventing accidents
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3. Outline
 Crane Hazards
 Crane types
 Industrial cranes
 Construction cranes
 Rigging (and “sling angle”)
 Controlling hazards
 Inspections and training
 Power lines
 Equipment failure and crane stability
 Other
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4. Crane Hazards
 Over 250,000 cranes in operation
 125,000 in construction
 80,000 general and maritime
 80 fatalities per year
 One death per thousand crane operators in their
working lifetime (45 years)
 Risk to citizens and other workers
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5. Causes of Crane Fatalities
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Electrocution 39%
Crane assembly/disassembly 12%
Crane upset/overturn 7%
Rigging failure 7%
Overloading 4%
Struck by moving load 4%
Manlifts 4%
Struck by counterweight 2%
Two-blocking 2%
Hoist limitations 2%
Other 6%
A. Suruda,et al, Crane-Related Deaths in the U.S. Construction Industry, 1984-94

6. Crane Types
 "Industrial cranes“
 Overhead
 Gantry
 Jib
 "Construction cranes“
 Mobile
 Tower
 Derricks
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7. Industrial Cranes
 Overhead Cranes
 Common in industrial facilities
 Supported by overhead rails
 Components
 Bridge
 Trolley
 Hoist
 Often pendant or remote operated
 Easy to use, little training required, no stability
problems
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8. Industrial Cranes
 Gantry cranes
 Similar to overhead cranes,
but supported by a mobile
frame which travels on the
ground
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Small (1000 – 10,000 pound
capacity) gantry crane
Large (600 ton capacity)
gantry crane

9. Industrial Cranes
 Jib cranes
 Pivot mounted boom
with trolley and hoist
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Wall-mounted jib crane
Floor-mounted
jib crane

10. Industrial Cranes
 Power hoist
 Usually electric or
air operated
 Chain hoist (or
"chain fall")
 Hand operated
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11. Construction Cranes
 Tower cranes
 Variable
height
“climbing
cranes”
 Used for
building
construction
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12. Construction Cranes
 Mobile cranes
 Crawler cranes
 Truck cranes
 Hydraulic cranes
 Boom telescopes
 May have jib
 Equipped with outriggers for
stability
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13. Hydraulic
Cranes
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14. Hydraulic Cranes
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15. Construction cranes
 Derricks
 Boom angle changes to
adjust horizontal
distance
 Often used in
shipyards, building
construction, etc.
 Gin pole
 Chicago boom
 Stiff-leg
 Etc.
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16. 16
Stiff-leg construction derrick
Mine-shaft rescue using a
gin pole derrick improvised
from an extension ladder

17. 17
Hay derrick

18. Rigging
 Rigging: The hardware and
equipment used to safely
attach a load to a lifting
device
 Wire rope
 Usually a "core" member to
increase flexibility
 Fiber Core (FC)
 Wire Strand Core (WSC)
 Independent Wire-rope Core
(IWRC)
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19. Rigging
 Fittings, sheaves
 Shackles
 Blocks
 Sockets
 Hooks
 May have safety latch
 Eyes
 Turnbuckles
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20. Rigging
 Always use rigging to connect the load to the
hook
 Materials
 Wire rope
 Fabric
 Chain
 Slings
 Straight (regular)
 Choker
 Basket
 Double, triple, etc.
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21. Rigging
Sling angle
 Stress on sling legs varies
with the angle
 Divide the load by the
number of sling legs, and
divide by sin of the angle
 For a two-legged sling, 2000
lb load and 60 degree,
stress = 1155 lbs on the
sling leg
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leg
lbs1155
60sin
1
legs2
lbs2000

leg
lbs2000
30sin
1
legs2
lbs2000


22. Controlling Crane Hazards
 Operators
 18 years old
 Physical exam
 Knowledge (training)
 Estimating load weight
 Signals
 Operation
 Skill (demonstration)
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23. Controlling Crane Hazards
 Inspection
 Frequent
 Daily, monthly
 Hooks, rope, crane operation
 Periodic
 At least annually
 Complete inspection - wear, damage, deterioration,
operation
 slings
 Testing
 Records
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24. Preventing Crane Accidents
 Contact with energized power lines
(45% of accidents)
 De-energize overhead lines
 Maintain minimum distance
 10 feet distance for 50 kv
 Over 50 kv, add 4 inches per 10 kv
 Use proximity alarms
 Warn when energized line is near
 “No fatalities” in 25 years, according to
mfg.
 Warning signs
 I-15 construction was a good example
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Sigalarm®

25. Warning label
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26. Preventing Crane Accidents
 Under hook lifting device problems
 Inspect, proper use, etc.
 Overturned cranes
 Assure a level and stable base for the crane
 Comply with load charts
 Weight
 Boom angle and extension
 Only vertical loads
 Wind can cause a significant side load
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27. Load Chart
 Load charts inside
the cab include
Structural
capacity and
tipping limits for
the crane
 Capacity is
highest for short
radius “over front”
loads with
outriggers
extended.
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28. Load Chart
Radi
us
Rear Over Over Side Over Front
18.8'
Boom
24'
Boom
29.8'
Boom
18.8'
Boom
24'
Boom
29.8'
Boom
18.8'
Boom
24'
Boom
29.8'
Boom
6 65,600* 65,600* 66,720*
8 57,250* 56,510* 57,250* 56,510* 61,150* 56,510*
10 50,760* 49,230* 47,060* 50,760* 49,230* 47,060* 52,520* 49,230* 47,060*
12 44,970 43,250* 41,310* 45,540* 43,250* 41,310* 46,390* 43,250* 41,310*
15 33,180 33,290 33,350 39,370 37,090 35,080 39,620 37,090 35,080
18 25,960 26,250 26,310 27,540 28,370 28,490 27,540 32,471 30,730
20 22,940 23,010 22,910 23,030 29,820 28,430
25 16,910 15,330 23,770
29 13,030 11,870 16,750

29. Preventing Crane Accidents
 Dropped loads
 Operating anti-two block device (upper limit switch)
 Proper rigging
 Inspection
 Boom collapse
 Inspection
 Stable base
 No overloading
 No horizontal loading
 Crushing by the counter weight
 Stay away from the rear of the crane
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30. Preventing Crane Accidents
 Proper outrigger use
 Level
 Fully extended
 Stable base
 Use cribbing to
distribute the load
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31. Outrigger Use
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Outrigger
with
cribbing

32. Preventing Crane Accidents
 Rigging failure
 Inspection
 Proper use
 temperature, angles, etc.
 Falls
 Fall protection for workers
suspended by crane "man basket"
or "suspended work platform“
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