After first appearing on jobsites in 2009, Caterpillar’s latest D7E dozers feature three new “productivity boosting” dozing features for optimized performance during grading work.
According to Caterpillar, Stable Blade Control complements operator inputs and auto adjusts the blade for smoother, more precise grades; Traction Control senses track slip and makes instantaneous smart blade adjustments to improve load consistency and maintain fuller blade loads, resulting in greater productivity with less undercarriage wear; and Slope Indicate provides a constant visual readout of the machine’s mainfall and cross slope for real-time grade and slope guidance without a dedicated grade control system.
What set the Cat D7E dozer apart from other dozers in 2009, and still in 2015, is its innovative diesel-electric powertrain, said to deliver up to 30% better fuel efficiency and 10% more production than its conventional D7R2 predecessor. Fuel savings, fewer mechanical parts to wear, reduced lubricant use, and increased production combine to lower owning and operating costs. The D7E meets U.S. EPA Tier 4 Final/EU Stage IV/Japan 2014 emissions standards.
Cat’s emissions reduction technology is transparent, requiring no action from the operator and no stopping for system regeneration. Engineers designed the SCR system such that its diesel exhaust fluid (DEF) could be refilled at refueling time. Across a variety of applications, the D7E typically has used DEF at a rate of 2 to 2.5% of fuel consumption with optimized fluid efficiency, defined as the amount of work done per unit of fuel and DEF consumed. In less aggressive applications, Cat says many operators will find they can complete multiple shifts on a single tank of DEF.
The D7E engine powers an electrical generator that sends current through armored cables to a solid-state inverter, which supplies dc current to accessories. The propulsion module, featuring state-of-the-art ac electric motors, delivers well-modulated torque via axles to the final drives. Electrical drivetrain components are sealed and liquid cooled with both oil and water to work efficiently in a wide variety of conditions and in high ambient temperatures.
A load-sensing hydraulic system continually adjusts hydraulic power to maximize work tool efficiency. Dozer blade choices include universal, semi-universal, straight, and angle blades. There are also special application blades to meet the needs for processing materials such as wood chips, coal, and waste. Rear attachment options include a multi-shank ripper, winch, drawbar, and counterweight. Purpose-built waste-handler and stockpile configurations equip the D7E for optimum service in such industrial applications.
The cab uses a center-post design for improved all-around visibility, an in-dash monitor for displaying real-time machine data, and a heating/ventilation/air-conditioning system that is self-contained and electrically powered. A speed recall feature allows pre-setting forward/reverse travel speeds, and then resuming set speeds by the touch of a button.
A tilt cab allows easy access to modular drivetrain components, and routine service points and sight gauges are grouped on the left side of the machine. A ground level service center houses the battery disconnect, hour meter, engine shutdown switch, and access lighting switches. An LED indicator in the service center, when illuminated, warns that powertrain and accessory systems are energized; when not illuminated, systems are safe to service.
In terms of other accessories that enable managers to make timely, fact-based decisions that can boost job site efficiency and productivity while lowering operating costs, Product Link helps fleet owners track location, hours, fuel consumption, idle time, and events by wirelessly reporting all via the online VisionLink user interface. Also, Cat’s AccuGrade is a dealer-installed grade control system that provides real-time in-cab guidance and automated blade movements to assist operators in efficiently attaining accurate grades in fewer passes, improving productivity as much as 50% over traditional methods.