Manitowoc MLC150-1, Руководство по техническому обслуживанию

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Manitowoc
Published 03-21-2021, Control # 264-01
5-49
MLC150-1 SERVICE/MAINTENANCE MANUAL HOISTS
5
Daily Inspection
The operating condition of the load block and the hook-and-
weight ball can change daily with use and therefore must be
inspected daily (at start of each shift). During operation,
observe for any defects which could affect their safe
operation. Correct all defects before using the load block or
the hook-and-weight ball.
Daily inspection and maintenance will include the following
points (see
Figure 5-34 and Figure 5-35 ):
• Clean the load block or the hook-and-weight ball.
• Lubricate the sheaves (if fittings provided), the hook
trunnion, the hook swivel, and any other part equipped
with a grease fitting at the intervals specified in the
“Lubrication Guide.”
• Tighten any loose tie-bolts, cap screws, and setscrews.
Check that all the cotter pins are installed with the legs
opened and trimmed.
• Check the sheaves for uneven wear in the grooves and
on the flanges. Check for loose or wobbly sheaves.
These conditions indicate faulty bearings or bushings.
• Check the fit of the wire rope in the groove of each
sheave.
- An oversize wire rope can crack the lip of the
sheave flange, causing rapid wear of the wire rope
and sheave.
- The groove must be larger than the wire rope, and
the groove must be free of rough edges and burrs.
• Check that the hook, the trunnion, and the swivel rotate
freely without excessive play. Faulty operation indicates
faulty bushings or bearings or inadequate lubrication.
• Check the swivel of the hook-and-weight ball for the
following conditions:
- Overloading—Spin the swivel by hand. If the motion
is rough or has a ratchet-like effect, the swivel
bearings are damaged.
- Side loading—This can cause the swivel to turn
freely in one spot and lock up in another.
This condition can also be checked by checking the
gap (see 4c,
Figure 5-34 ) between the barrel and
shank (to check, swivel must be removed from
weight ball).
If the gap is wide on one side and closed on the
other side, damage is present.
NOTE: The gap between the barrel and the shank is
normally 0.5 mm (0.02 in) to 1.3 mm (0.05 in). If the
gap increases, swivel-bearing failure is indicated.
• Check the load block for signs of overloading:
- Spread side plates
- Elongated holes
- Bent or elongated tie-bolts
- Cracks
• Check all of the welds for defects and cracks.
• Check the wire rope for wear and broken wires at the
point where the wire rope enters the dead-end socket.
Check the socket for cracks. Tighten the wire-rope clips
located at the dead end of the wire rope.
• Make sure that each hook has a latch and that the hook
latch operates properly.
Continued on next page.
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