Cat H-series embraces engine, hydraulic, control innovations

Caterpillar dealers around Australia will release five new H series wheel loaders, the 950H, 962H, 966H and the 972H this month. They replace the G series II introduced here in 2004.

Cat says the new range features key changes to enhance productivity and reduce owning and operating costs. New Cat engines feature ACERT technology and EU stage IIIa emissions compliance. Prototypes worked more than 100,000 hours in situ, principally to ensure the new engines did their stuff properly.

Also, a new load-sensing hydraulic implement system, which is proprietary to Caterpillar, works more efficiently for improved fuel benefits of up to 7% and a 20% increase in lift force over the previous models. This means faster cycle times and increased productivity.

Along with improved efficiency, the H-series also feature enhanced operator comfort, serviceability and reliability. Key changes include electro-hydraulic implement controls with simultaneous lift and tilt capabilities, a 5 0 forward-inclined left access ladder, a new cooling system, centralised hydraulic and electric service centres for improved maintenance and ground level access to daily and regular maintenance.

The 950H handles buckets of 2.7 to 4m 3, the 962H of 2.9 to 4.3m 3, the 966H of 3.5 to 4.8m 3 and the 972H uses buckets of 3.8 to 5.5m 3.

ACERT leveraged from trucks

Building on Caterpillar's truck record with on-highway ACERT engines, the 950H and the 962H leverage this technology with the Cat C7 engine, the 966H with the C11 engine and the 972H uses the new C13 engine. ACERT engines provide advanced electronic control, precise fuel delivery, and refined air management for outstanding engine performance and durability.

The technology builds on decades of Caterpillar experience in diesel engine design and manufacturing and takes advantage of a number of building block engine technologies. Some are recent innovations, while others have already proven themselves over millions of hours of use on the job.

Building blocks

Fuel delivery : The multiple-injection process introduces fuel into the combustion chamber in two precisely controlled microbursts. Injecting fuel in this way allows for precise shaping of the combustion cycle. For optimum performance, the multiple-injection process can be tailored for different applications and engine sizes.

Air management : Advanced air management also plays a critical role in reducing emissions. Stage IIIA off-road engines include crossflow heads and wastegated turbochargers. Advantages of wastegated turbos include higher boost levels over the entire operating range resulting in better low-end performance and response. Crossflow heads improve breathing for optimized combustion.

Electronics : The brain power comes from Cat ADEM 4 electronic controllers. They precisely govern fuel delivery and other engine processes and the ability to link machine performance directly with the engine.

The 7.2litre C7, the 11.1litre C11, and the 12.5 litre C13, are inline 6-cylinder engines with mechanically-actuated electronic fuel injection (MEUI) comprising four major components: injectors, a low-pressure fuel transfer pump, sensors to monitor speed, temperature and pressure, and the ADEM controller.

The controller is the brains behind engine responsiveness, self-diagnosis, emissions control and fuel economy. The system provides constant power through the operating range and a constant level of productivity, regardless of parasitic loads such as air conditioning.

For additional efficiencies, the H-series offers the new engine idle management system (EIMS), designed to maximise fuel efficiency by enabling customers to change idle speeds to best suit the application. EIMS has four idle control settings: hibernate (fuel economy), work (set idle per application requirements), warm up (cold weather operations) and low voltage mode. The system can reduce the fuel consumption up to 40%.

Hydraulics boost fuel efficiency A new load-sensing hydraulic implement system is a closed-loop system that automatically adjusts to operating conditions, to provide only the hydraulic flow required by the implement. The result again is optimum fuel efficiency. Additional benefits are found with a new proprietary valve, the M3PC priority proportional pressure compensated valve with integrated functions. The valve can adjust to changing power requirements on both the lift and tilt function to ensure no work stalls. With integrated functions on the valve, such as ride control and anti-drift, there are fewer line connections and less time required to retrofit.

Enhanced operator comfort The H-series electro-hydraulic implement controls feature soft detents. With electro-hydraulic controls and the M3PC valve, operators can simultaneously lift and tilt the bucket. The result is better bucket control and less spillage.

The control levers are detented in the kickout positions (tilt back or dump). When the lever is moved into soft detent, the operator will feel an increased resistance from the lever. Once the lever is in the detent, the operator releases it and the bucket continues to dump or tilt back until it reaches the angle that is preset by the kickout. Kickouts are programmable from within the cab for easy changes when the height of the target changes. An optional electro-hydraulic joystick is available with the same functionality.

The H-series features as standard, an air suspension seat that is 6-way adjustable, to accommodate all-sized operators. By managing normal machine vibrations, operator efficiency and productivity are improved. From the ground up, the H-series is designed with several features, both standard and optional, that reduce vibration.

The cab provides what Cat claims is best-in-class visibility to both the front and rear of the machine. Also, an optional rear vision camera is available. Reduced cab sound levels enhance operator comfort further while meeting the latest European Union sound regulations.

For easier operator access and egress, the new loaders each have a redesigned left-side ladder. The self-cleaning ladder features a 5 0 forward incline. A full-length ladder is standard on the right side of the machine as well.

As with the GII series, the H-series offers a choice of the standard steering wheel or the optional command control steering wheel. Turning the command control steering wheel about 70 0 from the centre point achieves full machine articulation. The system reduces operator effort in applications such as truck loading.