Fri February 23, 2007
Aggregate Equipment Guide
Komatsu America Corp. has introduced the HD785-7 off-highway truck with Tier II engine. The new truck features a powerful, clean burning Komatsu SAA12V140E-3 turbocharged, aftercooled engine that provides a maximum net output of 1,178 hp (878 kW). The engine is EPA Tier II emission certified.
Special features of the HD785-7 include:
• High Performance for Enhanced Productivity
The truck’s engine performance delivers acceleration and travel speeds with high horsepower per ton. High torque at low speed, acceleration and low fuel consumption ensure maximum productivity, according to the manufacturer.
The mode selection with Variable HorsePower Control (VHPC) system selects the appropriate mode (either power or economy) based on the working condition. The VHPC system detects the truck’s load and selects the optimum horsepower setting, providing high production and low fuel consumption.
The fully automatic transmission selects an optimum gear according to the travel and engine speed. To reduce fuel consumption, the shifting point is automatically selected depending on the machine’s acceleration. The automatic retard speed control system (ARSC) with a large capacity retarder allows operators to set downhill travel speed at a constant level so the operator can concentrate on steering. Its cooling oil temperature is consistently monitored so the speed is automatically reduced if the retarder oil temperature rises.
The Komatsu-designed electronically controlled all clutch modulation system with K-ATOMiCS optimizes the clutch engagement oil pressure at every gear for smoother shifting with minimal torque shock.
The HD785-7 features an extra-long wheelbase, a wide tread and a low center of gravity to haul its load at higher speed for greater productivity and deliver improved driving comfort over rough terrain.
• Enhanced Cab Design for Optimal Operator Comfort and Safety
The HD785-7 is equipped with an ergonomically designed cab.
The cabs are mounted with Komatsu’s viscous mounts to keep noise at a minimum and provide a low-vibration operating environment.
A low effort body dump control level makes dumping loads easier. The pedal-operated secondary brakes activate the four-axle parking brakes. When hydraulic pressure drops below the rated level, the parking brake is automatically activated. The five-way adjustable operator seat and the tilt-telescopic steering column provide an improved driving posture for increased driving comfort and better control over the machine’s operation, according to the manufacturer.
• Durability and Reliability Provide Easy Maintenance
Flat face-to-face O-ring seals are used to securely seal all hydraulic hose connections and to prevent oil leakage. The main harnesses and controller connectors are equipped with sealed DT connectors that provide high reliability and dust and water resistance.
The fully hydraulic controlled wet multiple-disc brakes ensure reliable and stable brake performance. Wet disc brakes are fully sealed to keep contaminants out, reducing wear and maintenance.
Both the filters and greasing points are centralized for easier servicing. To minimize operating costs, oil change intervals are extended to 500 hours for engine oil and 4,000 hours for hydraulic oil.
The Vehicle Health Monitoring System controller monitors the health conditions of major machine components, enabling remote analysis of the machine and its operation.
For more information, visit www.komatsuamerica.com.
This story also appears on Construction Equipment Guide.