Asphalt compaction finishing

The new Volvo CE PT220 pneumatic tyred roller is now available as a fine finishing machine for asphalt surfacing operations in selected emergent markets, the Middle East and Africa. The firm has opted to offer this machine across these markets due to a growing need for high quality finishing work in road construction projects.

According to the firm, this machine has been designed to handle a variety of asphalt finishing compaction applications and is said to be both versatile and productive. Meanwhile, the PT220 is said to feature a fuel-efficient and powerful Volvo diesel engine, offering increased performance, while also providing customers with new safety features.

To meet the needs of these areas, the PT220 is powered by a Volvo D5 Tier 3/Stage IIIA-compliant turbocharged diesel engine that delivers 99kW. The engine also exceeds the emissions requirements of these markets, allowing it to meet coming legislation. The machine also includes safety features, such as a ROPS sunshade, reversing alarm and automatic engine shutdown.

The Volvo PT220 delivers its compaction forces using its weight. Depending on the specification and ballasting used, weight can vary from 10.6tonnes up to 24tonnes. The machine can be adapted to work in a variety of applications by adding or removing ballast or by adjusting tyre inflation pressure. The positioning of the tyres, four each at the front and at the rear, is said to help ensure uniform surface coverage while in operation, allowing a compaction width of 1.98m. The tyres delivers a kneading action against the material surface that provides the smooth compaction finish. An isostatic suspension is fitted to the front tyres that is said to help to keep the roller stable on irregular surfaces as well as maintaining uniform contract pressure.

Another highlight of the Volvo PT220 is the dual seat with sliding console, which allows the operator to adjust it for the best view of the working area. In addition to equal forward and reverse speeds, the hydrostatic drive also features a high-speed travel mode that allows operators to get to the work site without delay. For increased compaction versatility, the maximum weight of the machine can be increased using a number of ballast options, including water.

Drive is supplied by a closed loop hydrostatic parallel circuit, which is fitted with two heavy duty radial piston motors. Travel speeds range from 0-15km/h. Forward to reverse directional changes are smooth, using a simple control lever to reduce operator fatigue. To maximise effort and minimise service requirements, the transmission delivers power directly to the rear wheel motors.

The operator platform and ergonomic layout of the controls is also claimed to help provide a low-fatigue workplace environment.

Water flow control from the rust-proof water storage tank is said to be consistent due to the pressurised water system on the Volvo PT220. The operator can also adjust water flow to the tyres to prevent asphalt being picked-up by the tyres. Water usage is also minimised, extending the periods between refills. For improved safety, an operator-presence switch incorporated into each seat, the PT220 will also shut down its engine and apply the brakes if the operator leaves the seat.

The engine and hydraulic components are easily accessible thanks to a swing-up engine hood and access step. Daily checks on the engine, battery, radiator and filters can be reached from ground level, helping ensure maintenance is properly conducted. A lockable vandal cover protects the operator console, while the lockable engine hood, fuel cap, water fill cap and deck access doors help deter theft and vandalism. Water nozzles and screens can be quickly removed, cleaned or replaced. The water spray system is rust proof with rubber distribution lines and brass spray nozzles.