Kato SR-300L, Инструкция по эксплуатации

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When extending the boom, confirm that the
boom sections 2 is fully extended before going
on to extend the boom sections 3 and 4.
If you extend the only boom sections 3 and 4 and
proceed to lift a load, the boom could break.
When you extend the only boom sections 3 and 4
for periodic inspection such as greasing the boom
etc., do so with the outriggers fully extended and
no suspended load.
(541A-0222-1E)
・ If you extend or derrick the boom while the hydraulic oil is hot and then leave it to rest, the
extended cylinder may retract as the oil cools. This is because the volume of oil has reduced
and is not a malfunction.
The degree of cylinder retraction depends on the amount of change in the oil temperature and
the cylinder stroke position and can be as much as several percent of the cylinder's stroke. This
phenomenon is most pronounced in the long telescopic cylinder or derrick cylinder and can
lower the hook position, so take care to avoid problems due to this effect. Take necessary
precautions in the following situations.
(1) If you wait with a load suspended from a long boom, avoid extending the boom further than
necessary and correct the boom length (extend it) from time to time.
(2) If the boom angle is low and the load is close to the rated lifting capacity, correct the boom
angle (by derricking) before the ACS alerts you to danger.
・ When extending the boom, make sure the hooks are far enough below the boom top to avoid
overhoisting.
・
If it is not possible to retract the boom sections 3 and 4, move the boom extension/retraction
emergency switch to the "release" position, set the boom extension/retraction switch to the
boom sections 3 and 4 side and depress the boom extension/retraction pedal backward to
retract the boom sections 3 and 4.
(611A-0075-0E)
NOTE
Extension sequence for each boom length