Maeda CC423S-1, Operation Manual

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35
CAUTIONS ABOUT HIGH TEMPERATURE OIL WHEN OPERATING CRANE
When hydraulic oil temperature exceeds 80 °C, high pressure hoses and seals can be damaged by
heat, and it may cause burning to skin from oil spray.
If temperature of hydraulic oil exceeds 80 °C, stop the operation and wait until the oil cools down.
Hook raising/lowering operation at high lift or continuous crane operation with the accelerator pedal
depressed will increase the hydraulic oil temperature. Take special care during such operation.
CAUTIONS WHEN OPERATING WINCH
• Select a suitable number of wire rope falls to the hook and boom
length to the mass of hoisted load.
Refer to “Operation 4. Handling Wire Rope” for details.
• Do not allow persons to enter the area below the hoisted load.
• When hoisting a load, always stop once at the “takeoff” position
where the hoisted load leaves the ground. Check subjects such as
load stability and load force, then hoist up the load.
• Do not pull laterally, pull toward you or hoist diagonally. Such
attempt may cause the crane to trip or get damaged.
• Over-hoisting of the hook block may result in collision with the
boom, snipping the wire ropes and causing the hook block and
load to fall and may lead to serious accidents. Take care not to
over-hoist the hook block.
• Be careful to prevent the wire rope and/or hoisted load from
contacting an obstacle such as a tree or steel when hoisting a
load.
If caught by an obstacle, do not forcibly wind up the hoist load, but
untangle the caught part before winding up.
• Do not use the winch drum wire that is wound up irregularly. If
wound up irregularly, not only does the wire rope get damaged
and have its lifetime shortened, but it may break causing serious
accidents.
Observe the following precautions to avoid wire rope from winding
up irregularly.
• Do not let the hook block tumble on the ground.
• When lowering the hook block long distances for underground
work, be sure to leave 3 turns or more of wire rope on the winch
drum.
• When decelerating from high-speed hoisting, ease off the
accelerator pedal to lower the engine revolution, and then slowly
return the right-hand side machine operation lever. A sharp
returning of the right machine operation lever while leaving the
revolution at a high level causes the hook to jump up due to the
rapid deceleration shock, resulting in an irregular winding.
• If the wire rope is twisted and causes the hook block to turn, fully
eliminate the twist before work.
Refer to “Operation 4.3 Corrective Actions Against Twisted
Wire Rope”.