Manitowoc Grove RT770E, Руководство по техническому обслуживанию

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UNDERCARRIAGE RT770E
8-4 Published 11/26/2014, Control # 447-05
Wheels And Tires
Description
The standard tire size for this unit is 29.5 x 25; also available
as an option, is a 29.5R25 tire.
Each wheel assembly (tire and rim) is mounted on the
planetary hub with 24 grade 8 lug nuts.
NOTE: The tire diameters, widths, and weights may vary
slightly depending on the tire manufacturer.
Off-highway tires are designed to operate with a certain
sidewall deflection or bulge. Correct air pressure ensures
prior deflection which, in turn, ensures proper traction,
flotation, support of load, and prevents excessive flexing of
the tire. Over inflation increases rim stresses, which results
in lowered rim life.
Refer to and adhere to the inflation pressures in the Load
Chart Book in the crane cab.
Maintenance
Mounting Wheel Assemblies
NOTE: Do not lubricate the wheel studs or lug nuts.
1. Raise the crane on outriggers so the wheels are off the
ground.
NOTE: Prior to wheel installation remove any dirt or grease
from wheel mounting surfaces.
2. Position the wheel assembly on the mounting studs.
Install the lug nuts and tighten them to 68 Nm (50 lb-ft) in
the sequence shown in Figure 8-2.
3. Ensure the wheel assembly is positioned properly on the
hub.
4. Continue to torque the lug nuts 461 Nm to 488 Nm
(340 lb-ft to 360 lb-ft) in the sequence shown in
Figure 8-2.
5. Lower the crane onto its tires. Retract and stow the
outrigger assemblies and the floats.
6. Road-test the tire, then retorque to 461 Nm to 488 Nm
(340 lb-ft to 360 lb-ft).
7. Maintain proper torque on wheel lugs and check for
proper wheel mounting. Retorque the lug nuts 80 km to
160 km (50 miles to 100 miles) after the wheels are
removed and reinstalled. This will reseat the lug nuts.
Check the torque every 800 km (500 miles) thereafter.
Typical Wear Patterns
Incorrect Tire Pressure
Too high air pressure Figure 8-3, View 1) gives rapid wear in
the middle of the tire. Too low air pressure (Figure 8-3, View
2) gives rapid shoulder wear.
WARNING
Possible equipment damage and/or
personal injury!
Driving the crane with a tire under inflated at 80% or less
of its recommended pressure can cause the wheel and/or
tire to fail. Per OSHA Standard 1910.177(f)(2), when a tire
has been driven under inflated at 80% or less of its
recommended pressure, it must first be completely
deflated, removed from the axle, disassembled, and
inspected before re-inflation.
CAUTION
Do not mix tires or rims from different manufacturers.
Vehicle stability can be affected.
DANGER
Do not attempt to demount or mount tires without proper
training. The high pressures involved can cause tire and
rim parts and tools to fly with explosive force, if proper
procedures are not used, causing severe injury or death
to personnel and damage to the crane and surrounding
area.
FIGURE 8-2