Manitowoc 999, Руководство по обслуживанию и ремонту

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Reference
Only
HOISTS 999 SERVICE/MAINTENANCE MANUAL
5-14
Published 05-16-17, Control # 233-03
Periodic Comprehensive Inspection
The comprehensive inspection must be done by a qualified
person. The inspection must include pulling all the rope off
the drum and carefully inspecting the entire length.
The inspection must include:
• All points listed under Daily Inspection .
• Inspection of rope diameter (see Reduction in Rope
Diameter ).
• Comprehensive examination for broken wires (see
Broken Rope Wires ).
• End connections: Check for broken wires or severely
corroded, cracked, bent, worn, or improperly applied
end connections.
• Areas subjected to rapid deterioration such as:
Sections in contact with saddles, equalizer sheaves, or
other sheaves where wire rope travel is limited.
Sections of wire rope at or near terminal ends where
corroded or broken wires may protrude.
• Inspection of boom sheaves, hook block sheaves,
gantry/mast sheaves, boom extension/jib sheaves, jib
strut sheaves, and hoist drums for wear.
NOTE: Damaged sheaves or hoist drums can accelerate
wear and cause rapid deterioration of the wire
rope.
Any damage of the wire rope found must be recorded and a
determination made as to whether to continued use of the
rope is safe. Refer to
Replacement Criteria .
Determining Frequency of Inspection
Intervals for comprehensive inspections may vary from
machine to machine. The inspection interval must be
determined by a qualified person and be based on such
factors as:
• Expected rope life as determined by experience on the
particular installation or similar installations.
• Size, nature, and frequency of lifts.
• Rope maintenance practices.
• Severity of environment, such as:
- Variation in temperature
- Continuous excessive moisture levels
- Exposure to corrosive chemicals or vapors
- Subjecting the wire rope to abrasive material
- Powerline contact
• Exposure to abuse and shock loads, such as:
- High-velocity movement, such as hoisting or
swinging of a load followed by abrupt stops.
- Suspending loads while traveling over irregular
surfaces such as railroad tracks, potholes, and
rough terrain.
- Moving a load that is beyond the rated capacity of
the lifting mechanism (overloading).
NOTE: Inspection intervals may also be pre-determined by
state and local regulatory agencies.
Replacement Criteria
The decision as to when a wire rope should be replaced is
the responsibility of the qualified person who is appointed to
review rope inspection records and evaluate rope condition.
The following are indications that the rope needs to be
replaced:
• Reduction in rope diameter and excessive broken wires.
See
Reduction in Rope Diameter and Broken Rope
Wires .
• Wear of one-third the original diameter of outside
individual wires
• Kinking, crushing, birdcaging, or any other damage
resulting in distortion of the rope structure
• Evidence of any heat damage from any cause
• Severe corrosion as evidenced by pitting
• Independent wire rope core (IWRC) or strand core
protrusion between outer strands
• Obvious damage exists from any heat source to include
—but not limited to—welding, power line strike, or
lightning
Reduction in Rope Diameter
A reduction in rope diameter is often the first outward sign
that the rope core is damaged. Reduction in rope diameter
can be caused by loss of core support, internal or external
corrosion, or wear of the outside wires.
DANGER
Falling Load Hazard
• As a wire rope approaches the end of its useful life,
inspections should be performed more frequently.
• All wire rope will eventually deteriorate to a point
where it is no longer usable.
• A comprehensive inspection of each wire rope must
be performed at least once a year.