Material Handling

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Rigging Hazard Awareness
Between the trolley hook and the load is
RIGGING
Ropes, Slings, Chains
Slings inspected daily
Proper storage when not in use
Suitable protection of rigging when in use (items
with sharp corners, etc..)
Rules for Rigging Safety
Know the weight of the load
Know the center of gravity of the load.
Make load attachment above the center of
gravity of the load.
Select hitch that will hold and control.
Know the rated capacity of slings and
hardware.
Rules for Rigging Safety
Select sling best suited for load.
Inspect all rigging before the lift.
Protect sling from sharp surfaces
Proper calculation of increased tension
caused by sling angles (on all rigging
components!).
Rules for Rigging Safety
Allow for D/d ratio on all wire rope slings.
Calculate reductions when using choker
hitch.
Keep personnel clear from lift area.
Lift load a few inches then check rigging
Know limitations of all lifting devices used.
Lift slowly and stop slowly
Rigging equipment for material
handling
Rigging equipment inspections (By a
Competent Person)
– Prior to use on each shift
– As necessary during its use to ensure that it is
safe
– Defective rigging equipment removed from
service
Not be loaded in excess of its
recommended safe working load
Rigging equipment for material
handling
Custom design grabs, hooks, clamps, or
other lifting accessories, for such units as
modular panels, prefabricated structures
and similar materials
– Marked to indicate the safe working loads
– Be proof-tested prior to use to 125 percent of
their rated load
Rigging equipment for material
handling
Alloy steel chains
Welded alloy steel chain
slings
– Permanently affixed
durable identification
stating
Size
Grade
Rated capacity
Sling manufacturer
Rigging equipment for material
handling
Alloy steel chains
Job or shop hooks
and links, or
makeshift fasteners,
formed from bolts,
rods, etc., or other
such attachments,
shall not be used
Rigging equipment for material
handling
Four grades:
–
–
–
–
Grade 28 General Utility Chain
Grade 43 High Test Chain
Grade 70 Binding Chain
Grade 80 Alloy Steel Chain: The only one used for
overhead lifting
G 80
Rigging equipment for material
handling
Alloy steel chains
Inspections
– Frequent
Visual examination by the user
Periodic
– Complete link by link inspection of the entire sling and all
attachments.
– Documented
Rigging equipment for material
handling
Alloy steel chains
CP inspections made & based on
– Frequency of sling use;
– Severity of service conditions;
– Nature of lifts being made; and
– Experience gained on the service life of slings
used in similar circumstances.
Such inspections at least once a year
Documented & available
Rigging equipment for material
handling
Wire rope slings
Protruding ends of strands in splices on
slings and bridles covered or blunted
Wire rope shall not be secured by knots
Except for eye splices in the ends of wires
and for endless rope slings, each wire
rope used in hoisting or lowering, or in
pulling loads, shall consist of one
continuous piece without knot or splice
Rigging equipment for material
handling
Mechanical Splice
Rigging equipment for material
handling
Hand Tucked Eye Splice
Rigging equipment for material
handling
Swaged Forged Eye
Rigging equipment for material
handling
Mechanical Splice
Rigging equipment for material
handling
Wire rope slings
Shall not be shortened with knots or bolts
or other makeshift devices.
Legs shall not be kinked
Basket hitch shall have the loads balanced
to prevent slippage
Padded or protected from the sharp edges
Rigging equipment for material
handling
Wire rope
Hands or fingers shall not be placed
between the sling and its load while the
sling is being tightened around the load
A sling shall not be pulled from under a
load when the load is resting on the sling
Rigging equipment for material
handling
D/d Ratio
D - is diameter around
which sling is bent.
d - is diameter of the
sling.
D
d
Rigging equipment for material
handling
When U-bolt wire
rope clips used to
form eyes
– U-bolt shall be applied
so that the "U" section
is in contact with the
dead end of the rope
“Never saddle a dead horse”
Rigging equipment for material
handling
Synthetic webbing (nylon, polyester, and
polypropylene).
– The employer shall have each synthetic web
sling marked or coded to show
Name or trademark of manufacturer
Rated capacities for the type of hitch
Type of material
Rated capacity shall not be exceeded
Rigging equipment for material
handling
Synthetic webbing (nylon, polyester,
and polypropylene)
Remove from service immediately if:
– Acid or caustic burns
– Melting or charring of any
part of the sling surface
– Snags, punctures, tears
or cuts
– Broken or worn stitches
– Distortion of fittings
Rigging equipment for material
handling
Shackles and hooks
– Manufacturers’ identification
– Never weld on hooks or shackles
– Working safety latch on hooks
Rigging equipment for material
handling
Recommended
Screw Pin Anchor
Shackle
Not
Recommended
Recommended
Round Pin Anchor
Shackle
Bolt Type Anchor
Shackle
Rigging equipment for material
handling
Never replace a
shackle pin with a bolt.
The load will bend
the bolt.
Rigging equipment for material
handling
Avoid eccentric
loads.
Bad
Good
Proper chocking of
shackles.
Bad
Good
Rigging equipment for material
handling
Check wear
Check cracks,
bending and
twisting
Check wear and
straightness
Pin always seated
Check opening
width
Rigging equipment for material
handling
LOAD
Hooks are designed to
apply the load at the
bottom of the saddle.
Rigging equipment for material
handling
Check for Wear and
Deformation
Check for
Cracks and
Twisting
Signs of
“Opening Up”
15%
10º
Check that
Hook is Not
Twisted
Check for Wear and Cracks
Rigging equipment for material
handling
Rigging equipment for material
handling
Approximately 70%-80% of a straight pull
Rigging equipment for material
handling
90° basket hitch is approximately twice the capacity of a straight pull
90
1000 LBS
500 LBS
500 LBS
How horizontal angle
affects slings capacity
1000 LBS 1000 LBS
60°
45°
30°
1000 LBS
1000 LBS
1000 LBS
Note: A good operating practice is to keep sling angles
from going below 60 degrees
Rigging equipment for material
handling
Calculating the load on sling legs
– Divide the total load by the number of sling
legs
– This quotient is the load on each leg if vertical
– Measure the sling from the load attachment
point, to the point where it connects with the
hook or lifting device; this is ‘L’
– Measure the vertical height from the top of the
load to the hook or lifting device; this is ‘H’
– Divide the length of the leg by the height of
the sling
L
H
LOAD
Load  Number of legs) X (L  H) = Load each sling leg
Example
Load = 120,000 pounds
4 load legs ÷ 120,000
equals 30,000 pounds
each leg if vertical hitch
Sling legs are 20 feet
Height from top of load to
lifting device is 15 feet
20 ÷ 15 = 1.33
Load on each leg is 1.33 x
30,000 = 40,000 pounds
120,000 lb.
Center of Gravity
A load is stable when:
– The hook is directly above the center of gravity of
the load
Estimate the center of gravity
Lift the load just enough to clear the ground
If the hook is not over the center of gravity the
hook will travel to the center of gravity
CG?
Center of Gravity
If necessary, set the load down and adjust the
rigging
If the load tips more than 3°, the rigging should
be adjusted
The longer the sling legs, the more stable the
load will be
B
A
The longer set of sling
legs (B) will improve
load stability
Disposal of waste materials
Materials are dropped more than 20 feet to
any point lying outside the exterior walls of
the building
– enclosed chute
Disposal of waste materials
Disposal of waste materials
Disposal of waste materials
Debris dropped through holes in the floor
without the use of chutes
– Completely enclosed with barricades not less
than 42 inches high
– Not less than 6 feet back from the projected
edge of the opening above
– Signs warning of falling materials shall be
posted at each level
– Removal shall not be permitted in this lower
area until debris handling ceases above
Disposal of waste materials
Scrap lumber, waste material, and rubbish
– Removed from the immediate work area as the work
progresses.
Disposal of waste material or debris by burning
– Comply with local fire regulations
All solvent waste, oily rags, and flammable
liquids
– Kept in fire resistant covered containers until removed
from worksite
Questions
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