Slipform Paver Controls Key Choices

Dec. 21, 2016

Infrastructure action is providing a shot in the arm for the slipform concrete paver market.

“The slipform paver market has been very solid,” says Randy Peters, national sales manager for Power Pavers. “Major infrastructure projects in developing countries have created strong demand.”

Add that to the the fact there is now a better-than-the-usual-Band-Aid highway bill in effect in the U.S., and you have an industry that is looking up on all shores. And what managers are looking at, manufacturers say, are the latest “smart” pavers and their advances in controls.

Cost of Ownership

Size class (lb.) Avg. price Hourly rate*
40,000-54,999 $338,467 $163.42
55,000-96,999 $471,431 $268.33
97,000 and up $677,809 $366.26

* Hourly rate represents the monthly ownership costs divided by 176, plus operating cost. Adjusted operating unit prices used in the calculation are diesel fuel at $2.30 per gallon, mechanic’s wage at $56.67 per hour, and money costs at 1.85 percent.

GOMACO product experts describe today’s concrete pavers as being all about technology that provides accuracy, ease of use, time savings, and of course, some creature comforts. They draw parallels between concrete pavers and cars.

“When you get into your car and you push [pre-set] No. 1, the mirrors, seats, and steering wheel adjust to your specific requirements,” says Kevin Klein, VP of research and engineering for GOMACO. “Concrete pavers are now expected to have telematics, diagnostic powers, and user-friendly controls.”

Not so long ago, such technology, ease of use, and control wasn’t possible. Pavers can now look ahead and anticipate.

“The steering and grade systems of the past can only see ‘what is,’” says Matt Morrison, GOMACO 3D team manager. “In other words, ‘This is where I go up and this where I go down. This is where I turn left and this is where I turn right.’ With [proprietary] G+ Controls and our 3D partners, machines can now see what is ahead and have the ability to anticipate the action.”

Peters also addresses the sea change.

“Technology is the biggest contributor to the creation of the ‘smart’ paver,” Peters says. “The days of manual control valves are over. The new generation wants to see buttons or joysticks to control their machines. The way this is done is through a CAN system. This concept allows programmed controllers to read and control all the function on a paving machine. The information is instantaneous and the reaction time of the controls is just as fast.”

Speed has become not only expected, but essential.

“These features allow contractors and operators to do things much faster,” Peters says. “An example would be transitioning from pave mode to transport mode. With a push of a button, all four tracks on a paver will automatically turn 90 degrees and align themselves to be able to drive onto a truck. With the aid of sensors, the control system on the machine knows exactly where the track is and can turn all four to the same degree. This saves the operator from trying to line up the tracks individually, hoping that they are aligned so it does not stress the frame. He can just go with the confidence that everything is aligned.”

Sensors and GPS also play large roles.

“Positioning makes everything possible,” explains R.J. Bumann, GOMACO G+ software team manager. “With sensors, 3D, and GPS, we not only know positioning, the GOMACO G+ Control System recognizes the position of the tracks, the position of the legs, the width of the frame on a paver, the position of the mold on a curb machine, and no tape measure is used. Now everything operates smoother, with accuracy, and correctly. The machine operates with precision and less effort because G+ works with this knowledge.”

Although the practice of setting stringlines isn’t entirely extinct, it may be on the endangered species list.

“The biggest advance in pavers is the stringless option,” Peters says. “Modern machines are set up to connect to a variety of stringless programs from providers including Leica, Topcon, and Trimble. These systems create a 3D image of the paver and the paving slab into a computer. Through GPS and total stations, the program guides the paving machine on the job site to pave the road or any paving project. There is no stringline to set up.

“These systems create smoother curves and allow more space for people to work around the machine without worrying about interfering with the stringline,” Peters says.

To realize all the benefits of smarter pavers, the technology has to be integrated. Here’s how one OEM describes its integration.

“The G+ Control System is electronic-over-hydraulic, and it is an intelligent platform that shares all information between the accessories through a two-way network,” says GOMACO’s controls team manager, Mark Brenner. “So now with various inputs like track-pulse pickup, GPS, and 3D- and 2D-sensoring, you can tell the paver what you want it to do and it will accomplish the command. For example, if you are going through a radius, the outside track will turn faster than an inside track. The controls on our paver are intuitive, easy to understand with more icons and less text, and simple for an operator to learn. This simple sophistication is a result of coordination between hardware and software and offers pinpointed diagnostics, quick and easy setup, and a high-production operation.”

Just how much technology to buy hinges on what a manager wants to do on current, and future, jobs.

“This is a huge shift going forward,” KIein says. “Everybody wants systems that are smarter and more intelligent. Everybody wants systems that are more predictive. Everybody wants systems that are more intuitive and more efficient. These are the next big opportunities in purchasing a slipform paver.

“So now you have mechanical devices, like a slew drive, and we sensor it,” Klein says. “You want to reference grade off of an existing slab, so we use a sonar sensor. You want to pave 30 feet wide without stringline and meet rideability specifications, so we work with our 3D partners. The G+ control system embraces this cornucopia of technology and connects it all together.” 

Power Pavers’ Peters goes back to basics to break down the buying decision.

“If the job consists of a bunch of turns and transitions, then a paver with the ‘smart’ features would be the better choice because you will get better results with less effort,” Peters says. “The machine would do what you need automatically and efficiently. If the job is a straight, flat road, then a traditional paver will do just fine. It all comes down to what you need to do and how much effort are you willing to invest to get the job done well. If investing in a modern machine will make the job easier and provide consistent results, then that will outweigh the increased cost.”

The acquisition cost, of course, is higher for more technology.

“Comparing the machines from 20 to 30 years ago, the cost of the modern ‘smart’ paver has almost doubled because of the technology and design time invested in the machine,” Peters says. “The benefit of these machines is that it is easier to learn to run the machine and more things can be controlled from the operator station. With a push of a button or a turn of a dial, you can control every feature of your paver. This means the operator can respond quicker to issues and not have to climb off and on the machine to make changes.”

Tim Nash, director, concrete products, for Wirtgen America, says that in addition to control systems, mold design, frame design, attachment availability, quality componentry, and manufacturer support all should be factors in a slipform paver purchase decision.

“Mold design is a key purchase criterion, as this speaks to ride quality, paving width change time, tolerance to a range of slump and mix design, productivity, and amount of work required behind the paver,” Nash says.

“Frame design has long been a core purchase decision factor, as it relates to strength, rigidity, and weight,” Nash says. “But in recent years, it’s broadened to other key elements that can significantly affect profitability and higher utilization, such as frame design features that decrease transport and set-up time, the ability to mount molds on the left- or right-hand side of the machine, and improved operator ergonomics.

“Attention to detail on attachments can often mean the difference in success on jobs,” Nash adds. “Whether considering side bar inserters, center bar inserters, dowel bar inserters, or super smoothers, it’s wise to focus on how these attachments mount/remove, access power sources, their programmability, ease of use, and in the case of bar insertion devices, understanding what factors contribute to accuracy of insertion and consolidation around the bars.”

At this month’s World of Concrete, and in March at Conexpo, both Wirtgen and GOMACO will introduce slipform pavers new to North America. Wirtgen’s mid-range SP 60 Series, first seen at Bauma, features three offset or inset paving models, the SP 61i (offset), and the SP 62i two-track and SP 64i four-track (inset) pavers.

“More features than ever operate hydraulically in the SP 60 Series,” Nash says. “Thanks to a new hydraulic concept, energy is now used much more efficiently, meaning it is available for new equipment options, such as trimmers, side bar inserters, a large delivery screw for offset applications, or the four swivel arms used to switch the machine from transport to working mode faster. The system starts as a basic version, and grows along with the number of modular equipment options selected.”

At Conexpo, GOMACO will introduce the next model in the GP family of slipform pavers. The GP4 will offer “all of the intelligence of the GP3” and is built with the strength and integrity to pave up to 40 feet wide, the company says. The Commander III Xtreme will be introduced at World of Concrete and Conexpo. The Commander IIIx will have the ability to pave a 24-inch radius and will feature the  G+ control system.