Wheel Loaders Designed For Comfort
- Published: Wednesday, 01 December 2004 07:00
The Caterpillar 980H medium wheel loader is pushing the 980G Series II to the side of the service road, as the company boasts improved operator comfort for increased productivity.
The 980H maintains the Command Control Steering introduced on the 980G, which also has become standard on the smaller H-series units. This replaced the standard steering and is equipped with a tiltable, telescopic handle. CCS allows the operator to steer the vehicle with his left hand, leaving his right hand free for the bucket controls. Bryan Argo, Caterpillar manager for midsize wheel loaders, says it provides smooth control with quick response. He says the a standard steering wheel requires 5,000 to 10,000 revolutions a day for a tight truck loading schedule, whereas the CCS only requires 700 to 1,000 revolutions.
Finger switches installed on the handle allow the operator to switch gears and maintain one-handed controls. The bucket controls on the right-hand side also are controlled with finger motions. And they are attached to the seat to prevent jostling. Both the CCS and finger-controlled levers and switches are intended to enhance operator comfort.
ìA comfortable operator is a productive operator,î Argo says. ìLet the machine do some of the thinking.î
Auto-dig is an optional feature that does just that. It is an automated operating mode that fills the bucket and raises it to a full carrying position. The operator drives into the pile as hard as he can. Then auto-dig takes over and goes through the motions when triggered by sensors on the hydraulics. When the operator is aligned with the truck, he takes over the controls to raise and dump the load. Operators can use the standard settings or they can customize their own. An operator can regain control by touching the bucket controls.
Argo says this reduces operator fatigue and allows more freedom to watch the rear of the machine when backing. The 980H also has an 8-cubic-yard bucket, compared to the prior model's 7.5-cubic-yard bucket, which also decreases loading time. Argo says two passes can fill an on-highway truck.
The 980H is powered by a C15 engine with ACERT technology that is Tier-3 compliant. It has a displacement of 15.1 liters. The engine has five ratings from 440 to 595 horsepower at 1,800 rpm to 2,100 rpm. Argo says the engine provides precise control of the combustion cycle without fuel degradation. The ADEM 4 control module has increased speed and memory and, a 120-pin engine connector in addition to a 70-pin original equipment manufacturer connector for vehicle systems communications. It has 595 horsepower compared to the prior engine's 525 horsepower.
The 980H employs an Electronic Clutch Pressure Control for smoother transmission shifts. ECPC technology has solenoid valves that are on the top of the transmission housing for easy access, and the transmission filter change interval has been doubled to 1,000 hours. The filter porosity has been reduced from 33 to 6 microns.
The 980H radiator's cores are single-pass flow instead of the two-pass flow cores on the 980G. It also has brazed construction that provides a stronger joint for higher heat transfer. Also, the radiator has six fins per inch.
Argo says additional cab sound insulation has cut the number of decibels from 80 to 76 decibels. ì(That) is like going from an old clunky car that is loud and sticking you in a quiet Lexus,î he says.
The 980H includes many accessories and standard features that he calls no-brainers.
For instance the ladder was given a five-degree incline, making it easier to enter and exit the cab. The rear fenders also have a new design. They provide 180-degree coverage of each wheel to double the coverage and reduce mud splatter. A non-metallic hood is two layers thick for rigidity. And an electro-hydraulic actuation system tilts the hood as high as 70 degrees in 30 seconds; the 980G required more than a minute.
Additional factory options also are available. A windshield-cleaning package makes it easier to access the full windshield area. It has steps and handrails to help access the cab front.
The optional Lincoln Quicklube automatic lubrication system greases pins and bushings while the machine is in operation. The Product Link helps tracking and managing the wheel loader. High-intensity quartz halogen work lights, rear-vision cameras and high-ambient cooling packages also are available.
Idle Management Saves on Fuel
A new engine idle software package that was introduced on the G series and carries over to the H-series midsize wheel loaders helps maximize fuel efficiency.
The software has four idle control settings: hibernate, work, low-voltage and warm-up. The default setting for hibernate mode is 600 rpm for the models 938H to 966H Series II, with low-idle work mode set at a default of 825 rpm. The 972 has a similar hibernate mode of 600 rpm, and the work mode has a factory default of 800 rpm.
The hibernate mode engages when the transmission is in neutral and the parking brake is set. And it automatically resets to working idle when the parking brake is released and the machine shifts into gear. Technicians using the Caterpillar Dealer Software Tool can adjust the working low idle according to the application.
Warm-up mode is intended for cold weather applications, and low-voltage helps prevent battery discharge. This mode increases the low-idle engine speed to 1,100 rpm to generate additional engine heat. It also monitors the coolant and inlet manifold temperatures.
The low voltage mode will ramp up to 1,100 rpm to charge the battery when voltage drops below a customized setting. It is most active in applications where electrical-current drain is high due to loads from attachments such as lighting and air conditioning.
Recent tests on the 938G II machines, fuel savings were at 40% when the machine was in hibernate mode set at 600 rpm, compared with the same model without the software, the company says. The 966G II showed fuel consumption savings of 45% in hibernation mode. The same machine also reduced fuel consumption by 16% when working in low-idle mode. Caterpillar says results will vary according to machine model and working applications.
Information Provided by Caterpillar