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Mobile Crane Inspection Guidelines for the Compliance Officers |
Printing Instructions
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Mobile Crane Inspection Guidelines
for OSHA Compliance Officers
Appendix C - Basic Crane Components
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In addition to reviewing the OSHA and American National
Standards Institute (ANSI)
standards/requirements for mobile construction cranes, it is important that
each inspector have a basic knowledge of crane components and their general
purpose. The following is a list of basic crane components which should be
included in any inspection. In addition to a description or purpose statement
photographs are provided to help the inspector recognize each item. The list
may not be inclusive, but is intended to be an aid for an inspector who may
not be a crane expert.
1. Manufacturer's Operating Manual
2. Machine Guarding |
INSPECTION ITEMS |
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1. Manufacturer's operating and maintenance manuals shall accompany all
mobile hoisting equipment. These manuals set forth inspection, operation,
and maintenance criteria for each mobile crane and not generally available
from any other source.
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1. Manufacturer's Operating Manual |
2. All exposed moving parts such as gears, chains reciprocating or
rotating parts are to be guarded or isolated.
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2. Machine Guarding |
3. Swing Clearance Protection
4. High Voltage Warning Signs
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INSPECTION ITEMS
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| 3. The swing radius of the counterweight shall be established and
guarded to prevent personnel or other equipment from being struck by the counterweight. Special attention shall be given to guarding of the swing
radius when near buildings or other structures. The swing radius guarding is
intended to simply be a warning device and not necessarily a barricade guard
rail. There are no strength requirements associated with swing radius
protection.
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3. Swing Clearance Protection
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| 4. High voltage warning signs shall be displayed on the exterior of the equipment on each side and on the counterweight of the crane.
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4. High Voltage Warning Signs
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5. Boom Stops
6. Jib Boom Stops |
INSPECTION ITEMS
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5. Boom stops are telescoping, shock absorbing, or hydraulic-type
safety devices designed and installed in a manner to stop or shut off
power to the boom controls. The purpose of the boom stops is to prevent
the boom from being raised to a point where the center of gravity is
shifted to the rear of the crane causing the boom to fall backwards from
to lack of resistance and/or control of boom movement.
Boom stops can be inspected and checked for proper function by raising
the boom very slowly until contact is made and power for boom movement is
stopped.
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5. Boom Stops
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6. Jib stops are restraints designed to prevent the jib from being
raised to the point that it overturns onto the boom sections. Jib stops,
like boom stops, are telescoping, shock absorbing, hydraulic devices,
designed to warn the operator that the jib load block has approached the
point at which overtipping/overturning is possible if raising the load
line continues.
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6. Jib Boom Stops |
7. Boom Angle
Indicator
8. Boom Hoist Disconnects |
INSPECTION ITEMS
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| 7. Boom Angle Indicators are required to indicate the angle of the
boom tip from the base section on a horizontal plane. They may be either
mechanical (activated by gravity) or electronic, with a display readout
in the cab. Accurate readout of boom angle determines load capacity and
working radius.
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7. Boom Angle
Indicators
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| 8. Boom Hoist Disconnects are designed to automatically stop the
boom from hoisting when the boom reaches a predetermined high angle
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8. Boom Hoist Disconnects |
9. Anti-Two Block
Devices
10. Power Controlled Lowering |
INSPECTION ITEMS
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| 9. Anti-Two Block Devices are designed to prevent a hoist block and/or
load from being hoisted into contact with the boom tip by putting
sufficient stress on the wire rope that it is either cut or stressed to
the point that the line separates and the load falls onto someone or
something. ANSI requires that all hydraulic cranes be equipped with anti-two block devices.
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9. Anti-Two Block
Devices
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| 10. All functions of hydraulic cranes feature "power controlled
lowering". Safety devices known as "holding valves" or
"counter balance" valves, which prevent uncontrolled decent in
the event of hydraulic pressure loss. To test the effectiveness of these
safety devices, retract the cylinders or lower the hoist drum with the
engine not running. This would apply to the boom lift and extension
cylinder as well as the outrigger cylinders and hoist drums. No movement
should take place without hydraulic pressure.
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10. Power Controlled Lowering
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11. Leveling Indicator Devices
12. Sheaves |
INSPECTION ITEMS
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| 11. Leveling of the crane is extremely important. If a crane is out of
level more than 1o it exerts a side load on the crane, and can effect
structural capacity. It also can increase the load radius when the crane
is rotated to another quadrant of operation.
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11. Leveling Indicator Devices
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| 12. All sheaves should be checked for cracks, grooving, or damage from
two-blocking. Undue looseness in the bearing or bushing should be noted.
The sheave's groove surface should be smooth and slightly larger than the
wire rope being used. It should be checked with a sheave gauge to be sure
it is the proper size for the wire rope being used. On most hydraulic
cranes, sheave guards which prevent the wire rope from coming off the
sheave, are removable pins. Be sure that all of these pins are in place.
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12. Sheaves |
13. Main Hoist and Auxiliary Drums
14. Main Boom, Jib and Boom Extensions |
INSPECTION ITEMS
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| 13.
Drum lagging and flanges should be inspected for cracks or
other deficiencies and winch mounting bolts should be checked. Any undue
movement of the drum on its bearings should be noted. The wire rope
anchoring to the drum should meet the manufacturers specifications
and must not be "overspooled". In other words, with the rope fully
spooled on the drum, the drum flanges must extend above the top wrap of
the rope. Any spoiling devices, such as rollers, or drum rotation
indicators, must be functioning properly.
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13. Main Hoist and Auxiliary Drums
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| 14. All components of the boom assembly should be checked for cracks,
bends, or other deformities. On hydraulic cranes, special attention should
be given to the topside of the boom where the extension sections exert an
upward force. All connecting pins and bolts should be checked. Wear
pads should be adjusted properly or replace if necessary.
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14. Main Boom, Jib and Boom Extensions |
15. Load Hooks and Hook Block
16. Hydraulic Hoses, Fittings and Tubing |
INSPECTION ITEMS
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15. Hooks should be examined to see if they are cracked or distorted
beyond allowable tolerances. No welding or heating should be done on hooks. Hooks and blocks should be labeled as to their capacity and
weight.
Connecting bolts on block cheek plates should be checked. Hook swivels and
sheave guards should also be checked.
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15. Load Hooks and Hook Block
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16. All hydraulic hoses, fittings, swivels, and tubings should be checked for
leaking. On flexible hoses, be sure that the working
pressure stamped on the hose is more than the working pressure it will be
exposed to.
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16. Hydraulic Hoses, Fittings and Tubing
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17. Outriggers
18. Load Rating Chart |
INSPECTION ITEMS
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| 17. Outrigger beams and housings should be checked for cracks or
distortions. Outrigger floats, or pads, should be checked for damage.
The floats must have the capacity to be securely attached to the outriggers.
Outrigger beams should be marked to indicate when they
are fully extended.
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17. Outriggers
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| 18. A durable load rating chart for the specific model and serial
number of the crane shall be accessible to the operator at his operating
or work station. All limitations, warnings, specifications and safety
data should be displayed
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18. Load Rating Chart |
19. Wire rope
20. Cab |
INSPECTION ITEMS
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| 19. Wire rope should be removed from service when the conditions listed
in 29 CFR 1926.550(a)(7) are found. They include outside wire wear,
reduction in diameter, broken wires, distortion, corrosion, or heat damage. Special attention should be given to standing rope, such as
pendants, at the end fittings. It should be determined that the wire rope
is the proper diameter, length, and type of construction for that
particular crane and it should be spooled evenly on the hoist drum.
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19. Wire rope
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| 20. The cab should be clean and free from clutter. All controls should
be labeled as to their function and free to return to the neutral position
when released, unless designed to do otherwise. All gauges and warning
lights should be operable and a fire extinguisher (at least 5-BC) should
be mounted in the cab. The seat should be securely attached and the cab
door should open outward and operate smoothly. Electrical and other
warning signs should be posted in the cab. All glass must be safety glass
with no cracks or distortions.
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20. Cab |
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