The new Caterpillar Cat CW34 pneumatic roller, which performs equally well on granular materials, as well as all types of asphalt mix designs, can be deployed on every compaction phase owing to its high contact pressures – consistently delivering density targets.

An eight wheel roller with an operating range of 10 t to 27 t, depending on the shedded or added ballast configuration, the CW34 provides an overall compaction width of 2 090 mm with 42 mm overlap.

This makes the machine well-suited for applications that include highway resurfac- ing, urban street lane additions, indus- trial sites, airport runways and other high production jobs.

Ballast choices include modular and non-modular steel, sand and water.

Machines supplied to the Southern African market will come standard with an open canopy, with the option of specifying a fully enclosed, air-conditioned cab.

“On the move, the oscillating front and rear tyres deliver vertical and horizontal forces that reduce air voids, ensuring surface uniformity, while the ‘air on the run’ feature allows the operator to automatically adjust tyre pressures to increase or decrease static loads for optimal surface quality,” explains Barloworld Equipment product manager Johan Hartman.

“The vertical suspension further improves results on uneven surfaces by uncovering voids and enabling consistent, even com-paction, so no unnecessary passes are required,” he says.

As with any compaction project, quality depends on keeping the tyres free of asphalt build-up. In this respect, Caterpillar has placed special emphasis on the CW34’s water spray, and optional emulsion systems, the latter providing additional protection against asphalt adhesion.

All eight tyres have dedicated spray nozzles and are fitted with self-adjusting scrapers.

Powered by a Cat C4.4 engine with ECO-mode for improved fuel consumption, the Cat CW34 operates efficiently at ambient temperatures up to 49 ºC under maximum engine load owing to the roller’s high-volume cooling system and large fan.

During operation, the CW34’s automatic speed control feature enables the operator to tune the system for increased speed within low, intermediate and high ranges.

When operating in intermediate and high, the system shifts smoothly through the speed ranges and offers a top speed of 19 km/h for quick movement around and between job sites. The system also has the ability to coast, leading to less fuel consumption and lower sound levels, an added benefit when working within urban areas.

“For extra precision, the optional Cat Compaction Control system provides an easy to use interface that keeps the operator informed of mat temperatures and rolling patterns,” Hartman adds.

Infrared temperature sensors, combined with mapping, keep the operator informed of current mat temperatures, machine position and where coverage has taken place.

“This intuitive system greatly enhances night-time performance, while also recording information for future data analysis and quality control documentation, another way that Caterpillar is supporting the road industry with best-in-class flexible pavement solutions,” he says.

Meanwhile, The Cat 6020B Hydraulic Mining Shovel is a new model in the extensive line of Cat hydraulic mining shovels. The clean-sheet design features a 22 t payload and 220 t operating weight and teams with the Cat 777G Off-Highway Truck for improved loading and hauling.

Designed for simplicity and reliability without compromising safety, the 6020B features a new cab and operator station with class-leading visibility provided by the large floor window and expansive windshield and side windows.

Unrestricted lines of sight to the crawler tracks and pit floor aid the operator when repositioning the shovel and when loading trucks. The cab design also includes two additional seats for a trainer and an observer. The 6020B three-seat cab design is the first in this size class of shovels.

Modular construction with a walk-through power module enables easy access to com-ponents and serviceability. Additionally, modular design facilitates shipping and field assembly of the 6020B. The single-engine configuration also simplifies maintenance. The 778 kW (1 043 hp) Cat engine powers advanced hydraulics, which deliver industry-leading system efficiency.

The new 6020B in backhoe configuration made a preview appearance at the inaugural bauma Africa 2013 and was made commer-cially available in the fourth quarter this year.