The new Cat® 374D hydraulic excavator, a direct replacement for the model 365C, combines added horsepower, stronger hydraulics and greater operating weight to boost overall performance, whether trenching, loading, lifting or handling attachments. Complementing these design basics are undercarriage improvements, a new range of buckets, operator-convenience features, safety enhancements and serviceability improvements. The fuel efficient 374D weighs 156,819 pounds (71,132 kg) and is designed for reliable, low-cost operation and long-life durability for optimum customer value.
More power, capable hydraulics
Rated at 476 net horsepower (355 kW), the Tier 3/Stage IIIA-compliant Cat C15 engine provides the 374D with 18 percent more power than its predecessor, the 365C. Cat ACERT™ Technology equips the C15 with advanced electronic control, precise fuel delivery and refined air management to deliver clean combustion and optimum fuel efficiency. The electronic engine controller, with flexible fuel mapping, allows the engine to respond efficiently to specific operating conditions, which means more work for each fuel dollar.
The C15 torque characteristics enable the engine to deliver full power at maximum rpm, resulting in efficient hydraulic pump operation and enhanced hydraulic response. In addition, the new titanium-alloy compressor wheel in the turbocharger increases reliability and performance at higher altitudes.
The 374D implement hydraulic system features a 10-percent increase in flow and a 9-percent gain in main pressure, resulting in a significant boost in hydraulic horsepower. The added hydraulic power combines with larger digging arm and bucket cylinders to yield 17 percent higher digging arm forces and 12 percent higher bucket forces on machines with the standard (reach) boom and arm configuration. For units in the mass excavation configuration, digging arm forces also are up by 17 percent and bucket forces by 5 percent. The net result is shorter cycle times and increased bucket fill factors.
Also new in the 374D implement hydraulic circuits are electrically controlled regeneration valves, which assure positive response from the boom and digging arm cylinders. In addition to further reducing cycle times, the new valves yield an estimated fuel saving of more than 2 percent. Also saving fuel is the hydraulically driven, variable-speed cooling fan.
Buckets, undercarriage, serviceability
A new line of buckets for the 374D are designed for added strength and durability to accommodate the higher digging forces of the new machine. Bucket types include general duty, heavy duty, severe duty and extreme duty. All Cat buckets feature K Series™ GET (Ground Engaging Tools). Work tools for the 374D extend the machine application into such operations as demolition, scrap processing and quarry work.
Undercarriage improvements include redesigned track links that operate with less stress, improved carrier rollers, longer recoil springs for extended service life and new forged idlers for improved durability. The new idlers are positioned lower to promote added stability, and a 6-inch (160-mm) track-gauge increase further enhances the stable work platform.
In addition, the carbody (the structure mounting the machine upper to the track assemblies) is reinforced at the roller-frame interface, and a new bolt pattern is used at the connection point. The boom foot, skirt and counterweight mounting area also have been strengthened for longer service life and increased durability.
To facilitate routine maintenance, the 374D uses protected fluid drain ports and self contained hoses, spin-on filters, an integral pre-cleaner in the air cleaner (with electronic restriction sensing), testing ports in all pressure circuits and pressurized fluid sampling ports to assure reliable samples. Also, the Electronic Power Control (EPC) is now located in the air-cleaner compartment, allowing the cab floor to be washed without risk of damage to the EPC, although the EPC and electrical terminals are weather-proof. For the operator’s convenience, fluid levels can be checked electronically at start-up.
Operator comfort and safety
For the operator’s convenience and comfort, the height of the joystick consoles is now adjustable, and the response of the joystick control levers can be adjusted to the operator’s preference through the monitor. The control pattern changer, also accessible through the monitor, allows operators to select preferred lever functions.
The monitor provides a full-color graphic display with comprehensive machine information (including fuel consumption) presented in either an English or ISO format. The monitor also displays images from the optional rearview camera.
To diminish heat and noise in the cab, the hydraulic control valve, pumps and reservoir are positioned away from the operator station. Metal-grating catwalks, 20-inches (500-mm) wide, are located on each side of the upper structure to provide safe access to maintenance points. The rear window, made of tempered glass, can be removed as a secondary exit.
Standard halogen lights provide exceptional jobsite illumination but can be replaced with optional High Intensity Discharge lights on the boom and upper cab if more illumination is required. Lights are time delayed to allow safe exit from the machine at night. As an added safety measure, travel, swing and implement functions are locked out when the counterweight removal system is activated.