Machine Matters: Utility size crawler excavators balance size and function
| March 26, 2009 |
Tracked excavators in the 16- to less-than-21-metric-ton range sit on the cusp between compact models and medium size diggers. Utility size crawler excavators will earn your appreciation as they perform roadwork without taking up the entire street, tackle demolition projects, dig trenches and lay pipes.
Most machines in this size class are available in configurations that let you choose arm lengths ranging from 8 feet 6 inches to 10 feet 2 inches, track widths from 20 to 28 inches, and bucket sizes to fit your applications. Transportation widths and heights vary by state and municipality but utility size excavators are usually within DOT parameters.
Excavator intelligence is expanding, too. Cat’s E-ceiling function, for example, monitors a height limit set by the operator and halts vertical movement of the boom/stick if the bucket exceeds that height. Machine control systems in this size category distribute information to remote computers, and GPS systems put a virtual security fence around the machine. Greater coordination between the hydraulic system and the engine, as seen on Terex’s new e-POS function, optimizes the excavators’ productivity while minimizing fuel consumption.
Features in current models include:
· Low effort joystick control patterns, like those found on the new Gradall and JCB excavators, make operating the machine easier, which can be an important consideration for new operators.
· Power boost functions provide extra hydraulic muscle on demand. New Holland’s model allows you to use the power boost feature continuously with no time limits.
· Increased dump heights of up to 22 feet 11 inches rival those of larger machines, good for loading trucks.
· High flow hydraulics power attachments that require extra oomph such as breakers.
· Models with front end dozer blades, like Kobelco’s Blade Runner, do double duty allowing you to backfill and grade with one machine.
· Comfort features such as significantly more powerful air-conditioning, lower noise levels, wider cabs and fully reclining seats help keep operators fresh and alert.
· Daily maintenance and servicing is streamlined with better component placement, improved access swing out panels and hydraulic oil filters that, as one manufacturer says, keeps the oil cleaner than the day it was put in.
Operator comfort is a key priority on Doosan’s DX180LC, featuring a six-way adjustable seat, ergonomically designed cab and transparent roof section for improved visibility. The DX180LC electronic power optimizing system ensures power and fuel consumption are maximized in every work mode with functions such as an auto deceleration system and a cross-sensing pump system.
Volvo’s EC160CL’s advanced control system balances engine power with hydraulic pump output to provide maximum digging, lifting, and production with minimal fuel consumption. The transparent roof hatch opens and combined with a reduced engine hood size gives improved visibility. A new hydraulic main control valve and higher torque swing motor improve the machine’s speed during combined operations.
New Holland E175B
New Holland’s newly redesigned E175B now has a 6 percent longer undercarriage on the EL version for added stability. A rear camera gives the operator a continuous view of the work area behind the machine using a dedicated screen in the cab. The E175B has normal and maximum-working modes and two attachment modes for one and two-way pump flow.
Deere 160D LC
Deere 160D LC’s 8-foot 10-inch width allows easy transport between jobsites. The 160D LC’s hydraulic recirculation system delivers efficient flow to the boom and arm for faster multifunction operation and cycle times. The Powerwise II engine/hydraulic management system maximizes power output and saves fuel. Ergonomic short-throw pilot levers provide smooth and predictable low-effort controls that go from backhoe to SAE style.
JCB adds the JS160NLC to their line up and features a slim 8-foot 6-inch width for easy transport. The cab’s front screens slide out of the way to prevent damage. The advanced management system alerts operators to potential service or operation issues. JCB says their Plexus filtering system allows the JS160NLC to run up to 5,000 hours between hydraulic oil changes.
Kobelco ED195 Blade Runner
Kobelco’s new ED195 Blade Runner excavator combines the features an excavator and a dozer. The ED195 comes standard with an 11-foot 4-inch, heavy duty six-way dozer blade that can be angled +/- 25 degrees and tilts 17.7 inches for grading and backfilling. A high-capacity hydraulic system is adjustable from inside the cab. The heavy lift function provides 10 percent more lift and swing capacity without time limits.
Komatsu’s PC200LC-8 excavator has 10 percent less fuel consumption than its predecessor. Five work modes include the P-mode for maximum production power and fast cycle times. E-mode offers P-mode working speed and economical fuel consumption for light duty work. Lift mode increases hydraulic pressure by 7 percent. B-mode delivers optimum engine rpms for one-way breaker operation.
Caterpillar 315D L
Cat’s D-Series 315DL has a new cab design that allows the falling object guard system to bolt directly onto the cab, either at the factory or as a later retrofit. Operating the 315DL is easy because the work and power mode switches are gone, making full power available at all times. Cat’s tool control system stores hydraulic operating information for 10 different work tools. And, Cat says the 315DL offers additional hydraulic pressure for more lift and breakout force.
Three work modes on the Case CX160B – automatic, heavy and speed priority – are controlled on the right hand console. Auto power boost increases the CX160B’s standard bucket digging force 10 percent to 26,527 pounds. The speed assistance system uses a double-pump combination for boom lifting and lowering, regenerating hydraulic oil to save fuel and produce quick machine responses. Case’s B Series excavators store up to 10 auxiliary hydraulic flow patterns to quickly adapt to different attachments.
Gradall XL3200 III
The new XL3200 III features Gradall’s signature low profile telescoping and tilting boom, allowing work under bridges and other obstructions where a knuckle boom won’t fit. Using a radio remote transmitter, Gradall’s remote control industrial maintenance models allow the operator to move into position for a clear view of both the undercarriage and the working boom. Gradall says their full tilting boom positions attachments to maximize productivity.
The wide, viscous-mounted cab, improved ventilation and large windows on Hyundai’s R160LC-7 excavator give operators a comfortable work environment with less shock and noise. A new computer aided power optimization system features two power modes, three work modes and two user modes. Hyundai says their power boost control increases digging power up to 10 percent. An auto deceleration function reduces engine speed to save fuel and reduce noise.
Hitachi’s ZX160LC-3 model’s redesigned cab gives operators more legroom. Short-throw control levers and armrests mounted independently from the seat provide fingertip control with less effort and the in-cab LCD color monitor displays up to 14 maintenance intervals, letting the operator check any of 32 machine operating parameters.