Furukawa Unic URW376C4U -T Series, Operation & Maintenance Manual

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3-3
SAFETY PRECAUTIONS ON CRANE OPERATION
6
Pulling a cargo sideways, straight, or
obliquely is strictly prohibited.
★
These operation may cause slewing mem-
bers, booms, columns, and derrick cylinder to
be damaged.
7
When a cargo to be lifted is detached
from the ground, stop lifting it up tem-
porarily to confirm safety.
★
When a cargo to be lifted is detached from
the ground, stop lifting it up temporarily to
make sure that the cargo is kept horizon-
tally, the crane maintains its stability, and
the rope slinging up the cargo is positioned
properly.
Then lift it up again after making sure of the
safety.
★
For lowering a cargo, stop lowering it
immediately before it touches the ground
then lower it again gradually.
8
Do not leave from operating position
with a cargo hoisted.
★
Lower a hoisted cargo onto the ground
before leaving from the operation site.
10
Do not stay under a hoisted cargo.
9
Do not get up on a cargo being hoisted.
★
This may cause a fall from the cargo being
hoisted.
11
Pay attention that wire ropes will
not be paid out unnecessarily to
prevent ropes from being wound around the
drum irregularly.
★
Operation such as paying out wire ropes
further with a cargo placed on the ground,
retraction and/or lowering boom loosen the
ropes to cause them irregular winding which
results in remarkable shortening service life
of the ropes.
★
Wind the first layer of rope firmly and
regularly around the drum.
★
Correct kinks of rope immediately with a
mallet.
12
Pay extra attention to underground
crane work in which the hook must
be lowered further than the work on the
ground.
★
When paying out wire ropes, be sure that
more than 3 turns of rope must always be left
on the drum.
★
Oil temperature is apt to rise easily if
repeated operation of winding up and down
the hook, especially in a high lift, is required.
★
Excessive high temperature of hydraulic
oil damages high-pressure hoses and gaskets
being employed to cause the oil to spout out
so that a scald may result.
13
Stop crane operation when tem-
perature of hydraulic oil exceeds
176°F(80°C).