crane safety for cranes and equipmnt.ppt

safety trainig for cranes

1. Crane and Hoist Safety

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

3. Outline
•Crane Hazards
•Crane types
–Industrial cranes
–Construction cranes
–Rigging (including “sling angle”)
•Controlling hazards
–Inspections and training
–Power lines
–Equipment failure and crane stability
–Other

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

5. Crane Hazards
•Major causes of crane accidents
–Contact with energized power lines (45%
of accidents)
–“Under hook lifting device”
–Overturned cranes
–Dropped loads
–Boom collapse
–Crushing by the counter weight
–Improper outrigger use
–Falls
–Rigging failure

6. Crane Types
•"Industrial cranes“
–Overhead
–Gantry
–Jib
•"Construction cranes“
–Mobile
–Tower
–Derricks

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

8. Industrial Cranes
•Gantry cranes
–Similar to overhead
cranes, but supported by
a mobile frame which
travels on the ground
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
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

11. Construction cranes
•Tower
cranes
– Variable
height
“climbing
cranes”
–Used for
building
construction

12. Construction cranes
•Mobile cranes
–Crawler cranes
–Truck cranes
–Hydraulic cranes
•Boom telescopes
•May have jib
•Equipped with
outriggers for stability

13. Hydraulic
Cranes

14. Hydraulic Cranes

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.

16. Stiff-leg construction derrick
Mine-shaft rescue using a
gin pole derrick improvised
from an extension ladder

17. Hay derrick

18. Rigging
•Wire rope
–Usually a "core" member to
increase flexibility
•Fiber Core (FC)
•Wire Strand Core (WSC)
•Independent Wire-rope Core
(IWRC)
•Classified by strand and wire
count
–6 x 31 IWRC is common rope for
overhead cranes, with 6 strands
of 31 wires each and a core

19. Rigging
•Fittings, sheaves
–Shackles
–Blocks
–Sockets
–Hooks
•May have safety
latch
–Eyes
–Turnbuckles

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.

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






leg
lbs1155
60sin
1
legs2
lbs2000

leg
lbs2000
30sin
1
legs2
lbs2000


22. •Operators
–18 years old
–Physical exam
–Knowledge
(training)
•Estimating load
weight
•Signals
•Operation
–Skill
(demonstration)
Controlling Crane Hazards

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

24. Preventing Crane Accidents
•Contact with energized power lines
(45% of accidents)
–De-energize 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 in SLC was a
good example

25. Warning label
  
                                                                   

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

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.

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

30. Preventing Crane Accidents
•Proper outrigger use
–Level
–Fully extended
–Stable base
•Use cribbing to
distribute the load

31. Outrigger Use
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“
–Secure fall protection “above the
hook”

33. Links
•Managing Mobile Crane Hazards
–http://www.cdc.gov/elcosh/docs/d0100/
d000104/d000104.html
•Crane, Derrick, and Hoist Safety
–http://www.osha.gov/SLTC/cranehoistsaf
ety/index.html