At the opening ceremonies of its new training center in Cartersville, Ga., Komatsu announced that it replaced the twin-engine PC1800 excavator/shovel with the single-engine PC2000LC-8, adding nearly 50 horsepower (a 5.5-percent gain). The first of these 445,000-pound excavators was on hand in the Cartersville demo area for trade journalists and Komatsu dealers to see how the single engine simplified the mining machine.
The PC2000 steps into the operating-weight gap between Hitachi's EX1900-5 BE and EX2500-5 BE. While the PC2000's dig depth is an impressive 3½ feet deeper than the EX1900, it's not deeper than the PC1800 that it replaced. Standard bucket size and engine horsepower remain about the same, if a little less than the smaller Hitachi's. Komatsu's Tier 2 power solution is its SAA12V140E-3 diesel, rated at 956 net horsepower.
Reducing the population of hydraulic pumps aboard the mountainous earthmover was a natural outgrowth of the single-engine design. Four much-larger pumps — a pair of twins — replace the PC1800's 10 hydraulic pumps, reducing power lost to heat and bringing about dramatic hydraulic-system simplification. For example, Komatsu did away with the dedicated swing pump, and the PC1800's dual drives in each track are replaced by single hydraulic motors.
The engine, hydraulic pumps, and cooling system (with enlarged oil cooler) are packed in a power module that can be lifted off the machine in one 22-ton load. The simplified power train also reduces required maintenance hours and the overall number of parts, which Komatsu says contributes to total cost reduction.
Boom-cylinder bore increased about 4 inches (from 280 mm to 300 mm) for faster cycle times. Paul Dawlearn, product manager for loading equipment with Komatsu mining, says that the unit, when swinging 30 to 40 degrees loading with a 15.7-cubic-yard bucket, clocks 25-second cycles. The PC2000LC-8 is designed to load a 100-ton truck in four to five passes.
A new, pressurized cab designed only for use in mining shovels is 30 percent larger than the predecessor's cab and cooled by a twin air conditioner. New damper mounts, in conjunction with power module packaging, attain car-like noise levels of 64.5 dB(A). Indeed, I had to turn down the air-handling fan in order to confirm that the engine had started when cranking the ignition, and had to listen closely to detect a sound difference when the engine revved to high idle. A new, 7-inch LCD monitor provides improved panel visibility to ensure a secure and smooth operation.
Suggested retail price on the Komatsu PC2000LC-8 is expected to be about $2.1 million.
