This article also appears in
Subscribe now »

The exterior of the new M318F and M320F excavators has been completely restyled, including a completely new ROPS-compliant operator's cabin featuring higher pressurization, larger door with added glass, and new mirrors with a heated option.

Caterpillar's wheeled excavator design based on customer input

Caterpillar says it solicited customer input for characteristics considered important when it was designing its new M318F and M320F wheeled excavators. Heading the not-so-short list were initial quality and reliability, low operating costs, operator comfort and safety, simplicity of operation and maintenance, durability, and environmental friendliness.

The new models are designed around those goals, while retaining what Cat says are the best features of predecessor models, including the Cat Smartboom, ride control, load-sensing hydraulics, dedicated swing pump, hydraulically driven cooling fan, large working envelope, and configuration/work-tool versatility.

The exterior of the new models has been completely restyled, including a completely new ROPS (rollover protection structure) compliant operator's cabin featuring higher pressurization, larger door with added glass, new windshield with parallel wipers, new mirrors (with a heated option), new rain visor and light protectors, a larger skylight, and a standard rearview camera housed in the redesigned counterweight as well as a right-side camera with a separate in-cab monitor.

Entering and exiting the cabin is now easier with redesigned three access steps and a new design door handrail. Inside the cabin, the left-hand console tilts to facilitate entering and leaving the seat, and the console includes an integral safety lever. Also new is the steering wheel, which is height adjustable and features a tilting column. The new cabin has an interior sound level of just 71 dB(A), and vibration levels have been reduced.

The standard lighting package for the new models now includes a counterweight light (enhancing the rearview camera function at night), three cabin-mounted lights, and light on the boom. Standard LED lights replace the previous halogen lighting for enhanced illumination, lower power consumption, and longer life.

An automatic system, when enabled by the operator, senses machine parameters and locks the axle-oscillation function and sets the service brakes, readying the machine to dig. This feature reduces operator fatigue by removing the need to constantly press the brake pedal. Brake and axle lock are automatically released when the operator presses the travel pedal again. Also, a new travel-lock system, engaged via the switch panel, combines implement-stop and swing-lock functions. Cruise control is standard, allowing the operator to choose the machine's exact speed. It can be activated via the Quick-Access button on the monitor.

The M318F and M320F incorporate a PIN-code anti-theft system. During short breaks in production, the system remembers the last code entered before engine shutdown and allows that code to remain active for a period of time.

A new blade for the M318F and M320F has a redesigned profile, allowing the blade to remain parallel to the ground at any height and assisting material to roll more easily in front of the blade.

The engine in the new models, as in predecessor models, is longitudinally mounted with the cooling package forward of the engine, resulting in ground-level access to routine maintenance points. An electric fuel-priming pump eliminates filling filters before installation. All the radiators are now grouped in the same compartment and the condenser can be tilted with no tool for ease of cleaning. Electrical and hydraulic components are now grouped in specific areas for ease of service and an automatic centralized greasing device (Auto-lube) is standard .

The Cat C7.1 ACERT Tier 4 engine is rated at 169 hp (126 kW) and features refinements that yield added torque and faster response to changes in load. The field-proven engine now integrates an emissions aftertreatment system, which requires no attention other than periodically replenishing the diesel-exhaust-fluid (DEF) tank. Emissions technology includes the Cat NOx-reduction system, SCR, DOC, DPF, and high-pressure/common-rail fuel system. The DPF passively regenerates, requiring no intervention by the operator and causing no interruption in the work cycle.

The optional Cat Bio HYDO Advanced hydraulic oil and bio-diesel (up to 20% mixed with ultra-low sulfur diesel fuel can be used without reducing the life of the systems.

An engine-idle shutdown system saves fuel by shutting down the engine when it has been idling for a preset amount of time. In addition, eco modes have been refined and reduce the engine speed with no reduction of power providing reduced fuel consumption with no compromise in performance.

A new electronic control hydraulic system combined with new medium-pressure and fan pumps enhances hydraulic response and reduces overall load on the engine for greater fuel efficiency.

The design of the engine and the aftertreatment system results in low fluid consumption for new models, conserving both fuel and DEF to lower operating costs. Depending on the application, fuel consumption for the new models can be as much as 10% lower than that of predecessor models.

Continue reading »