Furukawa Unic URW370C4U Series, Operation & Maintenance Manual

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11-17
HOW TO OPERATE CRANE
• Further paying out of the wire rope after the hook has reached the
ground causes the rope to be wound around the drum irregular-
ly.
Lifting up a cargo with the rope irregularly wound on the drum dam-
ages the rope which results in remarkable shortening of its service
life.
• When paying out wire rope longer such as down to underground
work site, make sure that more than 3 turns of wire rope shall always
be left on the drum.
• When the first layer of wire rope fails to be wound around the
drum firmly and regularly, ropes wound over the first layer
may dig into the inner layers to cause an irregular winding,
When the wire rope is unwound to or wound up from the first layer
of rope, wind it up/down slowly so that the first layer of rope can be
wound around the drum firmly and regularly.
• Stop the crane operation when hydraulic oil temperature exceeds
176°F(80°C).
Oil temperature is apt to rise easily if repeated operation of winding
up/down of the hook, especially in a high lift, is required.
CAUTION
To know approximate oil temperature by sense of touch:
158°F
(70°C)
You can touch the oil tank (Lower
part) with the palm of your hand
for 3~4 seconds.
176°F
(80°C)
You can touch the oil tank (Lower
part) with your finger tip for 1~2
seconds.
194°F
(90°C)
The moment you touch the oil tank
(Lower part), you will let the hand
off by reflex action.