New milling technology from leading players

Two major manufacturers, Caterpillar and Wirtgen, are introducing new milling machines. Both firms say that these new, high-production units will offer increased output compared with earlier generation equipment

From 178 Caterpillar come the new PM820, PM822 and PM825 machines, which are half-lane milling machines able to handle full-depth removal of asphalt and concrete pavements in a single pass. The firm claims that these units are highly productive and highly manoeuvrable. In operation the machines weigh 36.1, 36.7 and 37.5tonnes respectively while for transport they tip the scales at 32.2, 32.8 and 33.6tonnes. These high-power models offer cutting widths of 2.01, 2.235 and 2.505m.

The machines are powered by the Cat C18 ACERT diesel, which delivers 563kW and meets the Tier 4 Final/ Stage IV emissions standards. The mounting of the engine is designed to minimise vibration while the machine features a cooling system with an on-demand, variable-speed fan.

The PM820, PM822, and PM825 are hydrostatically driven by two variable-displacement propel pumps. Four-mode steering is standard, with a true-tracking alignment function providing steering precision, smoother cornering, and reduced track wear. The machines use a four-post design, with each leg post featuring an auto-levelling function for precise height adjustment.

The rotor is equipped with three-piece, quick-release tool holders and carbide-tipped cutting bits. Optional rotor systems are available, as are Cat Diamond Bits for precision cutting in specific applications. The cutting chamber has a design that is said to improve material flow, reduce wear on the chamber, and allow flush-cutting.

Chamber side plates move by independent hydraulic cylinders equipped with position sensors, ensuring that the side plates float at the proper level and eliminate binding. The rotor drive is belt-driven and the machine has three cutting settings to match rotor speed/torque with the conditions.

Optional diamond bits last up to 80 times longer than conventional carbide bits, extending intervals between bit maintenance, increasing production and reducing operating costs. These also reduce maintenance needs, improve fuel economy and cut machine vibration.

The PM820, PM822, and PM825 can be equipped with the optional, integrated Cat Grade Control system, which is a 2D-capable/3D-ready grade-and-slope system that automatically controls a preset rotor depth and cross slope. The system can be upgraded for full 3D control with the addition of optional equipment.

Cat Grade Control can be configured with contacting or non-contacting grade sensors including Cat sonic sensors and mounting hardware, the side plate position or optional inboard ski.

Meanwhile, 2395 Wirtgen’s new W 210 XP is a new high-performance machine that combines high engine power with an application-optimised machine transport weight. The firm claims that it is the most productive unit in its class and the machine is driven by a six-cylinder diesel delivering 571kW. This is said to allow the user to handle a wide range of applications, from surface course rehabilitation to complete pavement removal and fine milling jobs.

The W 210 XP comes equipped with a 2m milling drum unit as standard. However units with milling widths of 1.5m and 2.2m are also available as options. The machine has Wirtgen's Flexible Cutter System Light (FCS Light), which is said to increase versatility and utilisation. Both the 2m and 2.2m milling drums are FCS Light-compatible. This allows milling drums of the same width but with different tool spacings to be fitted without difficulty as required for the job at hand. All the milling drums are fitted with Wirtgen's HT22 quick-change toolholder system. The robust upper part of the system can be easily and quickly changed directly on site. This is said to reduce machine downtime and increase the lifespan of the milling drum.

Compact dimensions and comparatively low machine transport weight allow the

W 210 XP to be easily moved from one site to the next. As a result, the high-performance milling machine can be up and running in no time. Without the 29tonnes of water in its tank, transport weight is low so the machine can be moved on a light low-bed truck. Customers can get their large milling machine to its next job at a fraction of the cost.

The machine has an ergonomically designed operator platform. Most functions can be controlled by the multifunctional joystick mounted in the armrest. In this way, the operating concept of the new W 210 XP, devised by the Wirtgen designers with great attention to detail, allows high daily production rates.