Manitowoc Grove TMS9000-2 Series, Руководство по обслуживанию

Страница: 296 / 408

8-22
Published 01-14-2021 Control # 707-01
CARRIER TMS9000-2 SERVICE MANUAL
pads with synthetic lubricant containing Teflon. Do
not lube the face of the wheel or rim.
1. Install the wheel assemblies on the mounting studs.
2. Place the mounting ring and hub cover over the hub and
studs.
3. Install the lug nuts and tighten until the nuts are just
snug. Position the nut that is to be tightened on top.
.
4. Tighten the lug nuts to a preliminary torque of 68 Nm
(50 lb-ft) in the sequence as shown in (Figure 8-13).
Torque the lug nuts 610 to 679 Nm (450 to 500 lb-ft) in the
sequence as shown, (Figure 8-13). Retorque lug nuts 80 to
160 km (50 to 100 mi) after the wheels are removed and
reinstalled. Check the torque every 804 km (500 mi)
thereafter.
AIR SYSTEM
Description
The air system (Figure 8-14) provides the air supply and
control to operate the service brakes, parking brakes, air
suspension system, inter-axle and optional cross axle
differential locks, and tire inflation.
The engine-mounted air compressor provides air system
flow. The air system components are operated by the air that
is stored in four reservoirs underneath the frame.
An air dryer with integral governor is mounted under the
center front decking behind the front bumper. It is connected
between the outlet of the supply dump valve and the supply
reservoirs. Oil, water, and contaminates are removed from
the air during the compression cycle and when the governor
is unloading, the contaminates are removed from the dryer.
The air system is split into a primary system and a secondary
system. The systems are isolated from each other so that in
the event of a failure in one system air is retained in the other
system. By means of pressure protection valves, spring
brake valves, a reserve of air pressure remains to operate
the brakes through normal use of the brake pedal. Any
unusual loss of pressure should be investigated immediately
and corrected, so as to restore the full backup capability of
the system.
Theory of Operation
Through reciprocating motion, the piston in the compressor
compresses air with every cycle. The compressed air passes
through the supply dump valve and air dryer and into the
supply reservoirs (Tank A). A 1030 kPa (150 psi) safety valve
is installed on the air dryer module for protection from excess
pressure. The pressurized air flows to the primary service
reservoirs and secondary service reservoirs. Both primary
and secondary air reservoirs provide the supply for the dual
brake and spring brake control valves. Air to the service
brakes on axles #3, and #4 is supplied by the primary
reservoirs. The secondary reservoirs provide the supply for
the service brakes on axle #1 and #2.
Pressure protection valves are set at 731 kPa (106 psi) and
are basically check valves. They open at 69 to 103 kPa (10
to 15 psi) above it’s closing pressure. These valves protect a
circuit if a line is ruptured to ensure a priority supply to the
brakes. Pressure protection valve for tire inflation is set at
586 kPa (85 psi).
The compressor which is mounted on and driven by the
engine, is regulated by an air governor which vents the
compressor when a pressure of 896 kPa (130 psi) is sensed
in the air system. When pressure drops to 758 kPa (110 psi),
the governor will allow the compressor to supply the air
system to maintain proper system pressure.
FIGURE 8-13
Fo
r
Reference
Only