Mitsubishi Electric UM 10t, Инструкция по эксплуатации

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Maintenance and Inspection
Hoist check items are described in details below. Crane Safety Code (Clauses 34, 35 and 36)
prescribes to carry out daily inspection and periodic self-imposed inspection. Be sure to carry
out the maintenance and inspection.
Daily Inspection of Hoist
Before starting the daily work, the person responsible shall operate the hoist without load, and
check the following points.
No. Daily inspection item Description
1 Check the hoist operator working range for obstacles. Ensure safety in the working area.
2
Look over the traversing rail on the floor to check for
abnormalities.
Check also the stoppers.
3 Check that the limit switches function correctly.
If pushbuttons are not wired correctly, the limit switches
may not be effective.
After releasing your finger from a pushbutton, check
that the hook block traveling distance is within 20 to 50
mm. If the traveling distance is in this range, the hoist
can perform operation properly.
Also check the operation and the time required for
starting. If it takes 1 second or more to start the
operation, or if operation is not smoothly performed,
judge that the hoist is defective.
4 Check for strange noise, odor and vibration.
5
Check whether the brake is effective.
(For Type UR, check whether the immediate
stoppage is possible during high-speed lifting
operation.)
6
Check that the
hoist smoothly
moves as
directed by the
pushbuttons.
●
Check that the hoist moves
correctly at low and high speeds.
●
Check that the speed can be
switched smoothly between low
and high speeds without
abnormalities.
●
Check that the hoist stops after
decelerating. Check that the
distance required to stop is uniform
as usual.
The time required for acceleration to the high speed (60 Hz)
should be 1 second, and the time required for deceleration
from the high speed (60 Hz) to stoppage should be 0.5
seconds. After releasing the pushbutton switch, if the hook
block traveling distance is in the range of 50 to 80 mm, judge
that there is no problem.
7
Check that the hook block sheave rotates smoothly.
Check that the hook rotates easily, and that the hook nut
has been secured normally. Check that the wire rope
cannot come off the sheave.
Prevention of drop of load
8
Check that the wire rope has been properly wounded on
the drum. Improper winding will result in reduction in service life and
wire breakage.
9 Check the slinging tools for defects.
10
Check the whole body for abnormal overheat and color
change.