axle incorporates single reduction gearing mounted in the axle center. A
park brake is installed on the front axle carrier and is controlled by a lever in
The crane incorporates a hydraulically controlled steering system, utilizing
hydraulic steer cylinders mounted to the axles. The front axle is provided
with full power steering. The rear axle utilizes full hydraulic control and is
operated independently of the front steer.
SERVICE BRAKE SYSTEM.
The service brakes are hydraulically activated by a power boost unit and are
applied on all four wheels. The power boost unit receives its power boost
from the hydraulic pump flow divider primary circuit. In the event power
boost hydraulic oil flow is lost, an electro-hydraulic pump on the boost unit
will be energized (if the ignition switch is in ON and the brake pedal is
depressed) to supply the boost power. If both of. these fail, the manual
braking system will actuate the brakes by transferring as much force to the
brake cylinders as the operator can apply to the brake pedal.
HYDRAULIC SYSTEM AND COMPONENTS.
The hydraulic system is designed to provide adequate pressure and volume
for simultaneous operation of various crane functions.
The hydraulic reservoir is a 40 gallon (151 liter) steel tank located on the
right side of the frame. A full-flow, return-type, 10 micron filter and a sight
gauge are installed in the reservoir.
The crane has a two-section hydraulic pump mounted on and driven by the
transmission. The pump provides a total of 60.9 gpm at up to 2,750 psi. Oil
pressure is developed in each stage by a matched set of gears driven by the
driveshaft. As the gears turn, the chamber volume of oil between the gear
teeth increases as the gears pass the oil inlet section. This results in a low
pressure condition which allows atmospheric pressure to suction more oil
into the chamber. In turning, the gear teeth transport the trapped oil to the
outlet section where the chamber volume decreases and the oil is forced out
into the hydraulic system.