On the surface, soil compaction is pretty straightforward - a vibrating drum agitates soil particles until less air exists between them, creating a more stable structure. The machines that perform this task seem rather simple as well, however, today's manufacturers are working hard to bring you models which are more productive, simpler to maintain and easier for your customers to operate.
Single-drum soil compactors are one of the most common types of compaction equipment found in rental inventories. To be specific, the 84-in. drum machine is most popular due to its ability to cover a large area with a single pass.
According to Steve Wilson, manager marketing services/product manager at Bomag Americas Inc., this class of machine is quite common, but there are features available today which you should consider before choosing one for your fleet. Items like operating weight, rolling width, drum amplitude and dynamic force are things to compare and contrast, but so are some of the latest technologies that set some machines apart from others.
Doing it smarter
Many compaction equipment manufacturers have introduced automatic vibration control systems to help facilitate the most productive and efficient compaction performance. These systems work by utilizing a directed exciter mechanism so the roller automatically adjusts the output energy of the drum to optimize compaction. This allows the operator to know when maximum density has been achieved, eliminating unnecessary passes and overcompaction of the soil.
While this technology increases the acquisition cost of the machine, manufacturers argue that it pays for itself by increasing productivity.
"It is more expensive," says Wilson at Bomag, which offers its Variocontrol Intelligent Compaction™ system. "It's not typically seen in a rental environment right now, but as the technology grows, we'll begin to see it more and more."
Wilson notes that automatic vibration control technology offers several advantages. "It minimizes the time needed to achieve maximum results, there is no overcompaction and it allows for proof rolling to find weak spots."
Machine control systems for enhanced traction and gradeability are another area of advancement.
According to Wilson, systems such as these monitor the slip potential between the drum and rear rubber tires and then automatically adjust the hydraulic flow to deliver optimum performance for operation on severe grades or difficult traction conditions and to prevent the roller from stalling or "digging" itself into the material.
Lower cost of ownership
Everyone wants their equipment to be more economical, particularly the larger pieces of equipment that cost a lot to fuel.
Wilson points out that Bomag features Eco-Mode on its Dash 4 Series. On these machines, there are three throttle positions: one for idle, one for maximum rpm and another for Eco-Mode.
"The engine senses load demand and adjusts the engine rpm to meet the needs of that demand," explains Wilson. "As a result, the engine consumes less fuel and there are fewer emissions and noise."
Like automatic vibration control systems, Eco-Mode adds to the cost of the machine, but the savings on fuel helps offset the increase.
"It lowers the cost of ownership while the machine still performs at top productivity," Wilson says.
Other manufacturers offer similar systems. The concept comes from Europe, where the cost of fuel is much higher than it is in the U.S.
Shell kits, blades and more
One feature that's particularly suited to the rental industry is shell kits for converting smooth drums into padfoot and vice versa. This allows you to serve two customer bases with one machine. Particularly desirable in areas with mixed soils, shell kits improve the utilization of a single machine, thereby improving your return on investment.
Shell kits usually take about an hour to install and allow you to offer your customers the best of both worlds without the hefty investment in two separate machines.