TM 10-3930-675-100003 00-2THEORY OF OPERATION - CONTINUED0003 00STEERING SYSTEM1.The electro-hydraulic steering system provides three modes of steering control; two-wheel steer, four-wheel steer, andcrab steer.2.The variable rate steering system utilizes two front and two rear hydraulic steer cylinders and electronic wheel positionsensors connected to an electronic control module to maintain direction and control. The variable rate system allows thesystem to change or adjust to different modes of operation.3.An emergency steering pump is provided in the event the engine is inoperative. If the engine quits while operating theRTCH, the emergency steering pump provides sufficient hydraulic pressure to control the truck until it is brought to asafe stop.BRAKE SYSTEM1.The brakes are totally enclosed within the front and rear drive axle housings, next to the wheel ends.2.The brake system is a wet brake system that is comprised of three separate hydraulic circuits: service brake circuit, cool-ing circuit, and parking brake circuit.3.The brake system also includes six pressurized accumulators that provide adequate stored energy to stop the RTCH inthe event of engine shutdown.4.The service brake circuit is applied by depressing either the left or right floor-mounted hydraulic brake pedals. Brakepressure is applied to eight cylinders per side within the front axle and one cylinder per side in the rear axle.5.The brake system cooling circuit cools the brake disks using oil pumped from the main hydraulic system through brakechambers during operation.6.The parking brake assemblies are mounted at the input flanges of the front and rear axles. The brakes are applied byspring pressure and released hydraulically. A warning buzzer sounds if driver leaves seat without applying the parkingbrakes. In the event of an emergency the parking brake may be utilized to stop the truck.HYDRAULIC SYSTEMThe RTCH hydraulic system is comprised of the following major components that provide hydraulic power to operateand control the container tophandler, boom, steering, and brake systems. In addition the hydraulic system is used to place thecab and bogie wheels into transport mode.1.Three variable piston-type hydraulic pumps are driven by the transmission power take-off (PTO). The pumps providehydraulics for the steering system and tophandler.2.One double vane-type pump is driven by the transmission PTO. It provides hydraulics for the boom cylinders, service,and parking brake systems.3.One single-vane pump is driven by the engine. It provides hydraulics for a cooling fan.4.Main valves control the main hydraulics. The valves are controlled by an electro-hydraulic servo system from the joy-stick control in the operator’s cab.5.High-pressure oil filters clean hydraulic oil before returning oil to the reservoir. Breather filters allow venting of thehydraulic reservoir.6.Hydraulic system oil cooler and fan maintain and control hydraulic oil temperature. The cooling fan is powered byhydraulics from an engine-driven hydraulic pump.7.Emergency systems: one ground-driven hydraulic pump maintains steering control in the event of engine failure; a 24-volt electric hydraulic pump provides power to lower boom and release the twist locks in the event of engine failure.The electric pump also provides a means to place the operator’s cab into the transport mode.
Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business
