Compaction innovations from key firms
First publishedin World Highways
Ammann's Service Link tool will be offered on the larger compactors also
The major manufacturers are introducing an array of advanced asphalt compaction machines - Mike Woof writes
New compaction machines are coming to market from an array of manufacturers, aiming to increase output and efficiency for road contractors. One of the most notable developments is with Hamm’s launch of a production hybrid compactor model, while other firms say they are also working on similar systems. However, several manufacturers have introduced new and improved machines with superior performance to earlier designs.
From Ammann comes a new hardware upgrade for its lightweight compaction tools called Ammann ServiceLink. This offers a simplified digital, machine data monitoring tool for battery status and operating and maintenance times. It also reduces downtime caused by recharging or expensive battery changes. Low battery levels are identified, enabling charging processes to be adapted to operating requirements. A technician can mark replacement parts as missing on the machine – this information is then automatically available everywhere the next time the app is used. The Wi-Fi-aided system is said to offer additional benefits with regard to planning construction site operations and fleet management. The app provides a clear overview of stored data and users can plan maintenance intervals.
The ServiceLink relay has been an integral component of all new electric-start compactors worldwide since the beginning of 2018. ServiceLink can also be retrofitted to older machines equipped with a battery up to 30V. The system will also be offered in the firm’s heavy compactors in the future.
Meanwhile BOMAG is now offering split drums on its Tango4 oscillating asphalt compactor, as well as dual amplitude vibration on its small asphalt compactors. The split drum feature on the oscillating drum machine allows the unit to turn tighter corners without damaging the road surface. According to BOMAG, the firm is seeing an increase in demand for its oscillating type rollers as these machines are well-suited to compaction jobs of thin wearing course materials, without risking damaging aggregates. The split drum design further increases the capabilities of the machines by allowing them to operate in urban areas with narrower streets, without risking damaging the newly laid road surface.
Hamm's innovative hybrid machine is now available as a production model
The new version of the Tango technology benefits from a direct drive system, without drive belts. As a result, the firm claims that its novel gear-driven system is maintenance-free and allows for the oscillation system to work on split drums, which was not possible before. In addition, the new rollers have wear-resistant drums made of special steel, which are said to allow a service life of 6,000 hours.
And the compact asphalt rollers in the 3-5tonne class now offer dual amplitudes. This new feature allows the BW 135 AD-5 and
BW 138 AD/AC-5 models to be used for a wider range of applications. A rotary switch allows the operator to switch between amplitude. On a variety of applications, the high amplitude of 0.5mm provides fast and economical compaction. The lower amplitude of 0.2mm in the front and rear drums provides more sensitive compaction of thinner layers and minimises the risk of crushing aggregates. A four-cylinder Kubota engine drives these tandem rollers which have a working width of 1.3m or 1.38m.
From Caterpillar comes a range of improvements offered by the optional Cat Compaction Control. This features Pass-Count and Temperature Mapping systems combined with infrared temperature sensors and GPS mapping. The system gives an operator data on current mat temperatures, machine position, pass-count and pass coverage. This boosts night-time rolling pattern performance in particular, recording information for future analysis and quality control.
The company is also offering different vibratory options including Oscillatory Vibration, Dual Amplitude, Dual Frequency, Versa Vibe, and Five Amplitude systems. The Versa Vibe system provides a 2-in-1 machine with four amplitudes and two frequencies. This has two settings for lighter hitting and higher working speeds on thin lifts; and two settings for heavier hitting, and slower speeds, on thick lifts or those with challenging mixes. The five-amplitude system offers a wide range of amplitudes with a single frequency, while the two amplitude, two frequency system offers thin lift, thick lift compaction. These proven vibratory systems are now complemented by the combination of vertical vibration in the front drum and Oscillatory vibration in the rear drum.
From BOMAG comes an improved oscillation type compactor
The design combines Caterpillar’s high-performance vertical vibration on the front drum with oscillation technology on the rear drum. The front drum with vertical vibration is available in two amplitude, five amplitude, or Versa-Vibe systems that provide initial compaction, while the rear drum with oscillatory continues the excellent performance for optimal smoothness and density.
The oscillatory system uses a pod-style eccentric weight technology developed by Caterpillar and offers a two-year/2000-hour service interval. The novel belt-drive is said to deliver twice the load capacity of timing belt systems.
Other features include a newly designed centre-articulating hitch said to ensure mat contact and a smoother ride over uneven surfaces. An offset hitch option extends coverage up to 170mm for operation next to obstacles such as kerbs and gutters. Power comes from a Cat C4.4 engine rated at 106kW with Eco-mode and automatic speed control.
Moving down the range, the new CB1.7 and CB1.8 weigh in at 1.7tonnes and 1.8tonnes respectively. The machines are said to be easy to operate and transport, with a single point lifting option and durable hitch design. The foldable ROPS option allows the machine to move under and around low structures. The high amplitude vibratory system combines with large diameter drums and an eccentric weight design to deliver high compaction performance.
One of the most innovative launches for the compaction machine market has come from Hamm, with its novel HD+ 90i PH hybrid tandem roller now being offered as a production model. This follows extensive testing of the hydraulic hybrid package in on-site conditions in various countries. The drive system for this 9tonne compactor combines a conventional diesel with a hydraulic accumulator package. The diesel engine provides most of the power to drive the machine and the hydraulic accumulator then cuts in for peak power requirements. The system offers savings on fuel, as well as operating costs, with the same compaction performance as a standard machine.
BOMAG's small twin drum machines now offer greater versatility
As peak power is only required for starting up or switching on the vibration/oscillation system, the hydraulic accumulator allows the machine to operate with a 55.4kW diesel, instead of the 85kW engine normally required for a 9tonne class asphalt compactor. The smaller engine means that there is no need for a complex emissions control system, further reducing maintenance costs. If a lot of power is called for, the hydraulic system functions as an auxiliary drive, supplying a maximum short-term load of up to 20kW. Maximum power is usually only needed for a matter of seconds, leaving time to recharge the accumulator.
Several variants are available, including: double vibration (VV); double vibration with split drum (VV-S); one oscillation and one vibrating drum (VO); one oscillation and one split vibrating drum (VO-S); as a combi roller (VT); and as a combi roller with split vibrating drum (VT-S).
In addition, Hamm is offering an improved version of its GRW 280i rubber tyred asphalt compactor. The company has equipped the new model with a Tier 4 emissions compliant diesel as well as the firm’s sophisticated Easy Drive control system. It has a high seating position, large cab glass area and sloping engine cover, helping to ensure a good field of view.
The firm’s Easy Drive system was first fitted to the firm’s DV+ asphalt compactors but is now being installed on other machines such as the GRW 280i. The system has a small number of switches while all Easy Drive rollers have a steering wheel. Drive control is by joystick with push-button switches on the armrest. All the control systems on the firm’s compactors share a similar layout.
Modifications have been made to the ballast space between the wheel sets and the open-bottomed compartmented frame. Prefabricated steel, magnetite or concrete ballast bodies can be inserted or removed using a fork-lift truck. The machine has a hydrostatic rear-axle drive, allowing precise speed control. The GRW 280i also has a redesigned front steering axle with disc brakes while an optional anti-slip control ensures traction when working on uneven ground as well as on surfaces with varying temperatures. A novel suspension system is said to optimise weight distribution.
Power comes from a Tier 4 Final compliant four-cylinder diesel, delivering 85kW that features DOC and SCR emissions control equipment as well as automatic regeneration. The firm will offer a Tier 3 variant for use in developing markets.