Komatsu WA20-2, Operation & Maintenance Manual

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12.17 HANDLING THE TIRES
12.17.1 PRECAUTIONS WHEN HANDLING TIRES

CAUTION
If a tire has reached any of the following service limits, there is
danger that the tire may burst or cause an accident, so to ensure
safety, replace it with a new tire.
‡ Service limits for wear
fi When the remaining depth of the groove on construction
equipment tires (at a point approx. 1/4 of the tread width)
is 15% of the groove depth on a new tire.
fi When the tire shows marked uneven wear, stepped wear
or other abnormal wear, or when the cord layer is exposed.
‡ Service limits for damage
fi When there is external damage extending to the cord or
when the cord is broken
fi When the cord is cut or there is dragging
fi When the tire is peeling (there is separation)
fi When the bead is damaged
fi For tubeless tires, when there is air leakage or improper
repair
Please contact your Komatsu distributor when replacing the
tires. It is dangerous to jack up the machine without taking due care.
12.17.2 TIRE PRESSURE
Measure the tire pressure before starting operations, when the
tires are cool.
If the tire inflation pressure is too low, there will be overload; if
it is too high, it will cause tire cuts and shock burst. To prevent these
problems, adjust the tire inflation pressure according to the table
below.
12. OPERATION 12. OPERATION
WA20 WA30 WA40, 50
Air pressure
MPa (kgf/cm
2
)
0.18 (1.8) 0.2 (2.0) 0.18 (1.8)
WA20 WA30 WA40, 50
Air pressure 0.20 – 0.22 0.22 – 0.24 0.20 – 0.22
MPa (kgf/cm
2
) (2.0 – 2.2) (2.2 – 2.4) (2.0 – 2.2)
If the deflection of the tire is excessive, raise the inflation
pressure within the limits given in the table below to give a suitable
deflection.