From the first time Skanska heard about JLG’s new self-leveling boom lift, they were all in.
Tragedies in the industry had led Skanska to believe there must be a better way to work at height on uneven ground. Here was their answer.
The JLG® 670SJ boom lift uses a fully integrated, smart adapting steel chassis with self-leveling technology to automatically adapt to terrain on slopes up to 10 degrees in any direction. This means the 670SJ can more easily navigate rough job site terrain while the platform is elevated with full machine functionality, and it reduces the need for cribbing or pregrading the pad in order for it to get to work.
The model, demonstrated at ConExpo-Con/Agg 2020 in Las Vegas, goes into production this fall.
Contractors like Skanska, who have been early users of the 670SJ, say it lowers the risks of tipovers, makes operators more comfortable while traveling at height, improves access with its ability to get closer to the work area, and saves production time spent leveling the site before work can begin.
Their feedback from the field shows the 670SJ’s next-level technology is highly anticipated, and that it’s a model that rental companies will want in their fleets.
Putting Skanska’s Crews in a Better, Safer Position
It was 2017 when Mason Ford, director of sustainability and equipment services for Skanska, met with the JLG Industries team to share the contractor’s enthusiasm over the self-leveling chassis, at that time only a concept.
“We have been a supporter of it since the moment we heard they were building it,” Ford says.
Once ready for the field, Skanska put the 670SJ to work on the Lynnwood Link L300 project in Mountlake Terrace, Wash., a nearly 4-mile raised extension of the Sound Transit rail line outside of Seattle. Skanska USA, headquartered in New York City, NY, is the sole contractor for the project.
Ford says it was the perfect test case for the self-leveling boom lift, because of the site’s unprepared surfaces located where they needed to access girders for the line. Normally for that type of work, Skanska would use a 60-ft boom lift only after a significant amount of grading, which can take two to three hours.
This means extra machines are basically doing unproductive work, since the pad would need to be graded out once the boom lift’s portion is completed.
“It would also involve cribbing and blocking,” Ford says. “Even more so, it would mean slower project transitions and production, because to do a lot of the work, the operator would have to boom down, move the lift on an uneven surface to get to the next prepared work surface, and then raise back up and stretch back out to do the work.”
On top of this, the creation of the pad in congested areas may prevent other equipment from accessing the site.
“It's more than time and direct cost — it's whether you even have the opportunity to make that footprint available,” he says. “There's even cases where instead of using the 60-ft boom lift, we'd have to go to an 80-ft, because we need more reach to access the area.”
But none of these challenges are concerns for the 670SJ, which offers a class leading 67-ft platform height, horizontal reach of 57 ft 1 in, and 550-lb unrestricted and 750-lb restricted capacity. The model is compliant with the ANSI A92.20/CSA B354 standards, features 45% gradeability, and elevates to full height in just 101 seconds.
Because the 670SJ features four independent control arms instead of a solid oscillating axle in the front and a fixed axle in the rear like with traditional boom lifts, each wheel is attached to an arm that separately adjusts as sensing technology recognizes uneven ground.
Nate Hoover, director of product management and marketing for boom lifts at JLG, says the 670SJ’s LCD screen in the control box will notify operators if they are nearing the slope limits of the machine.
“The 670SJ provides real-time machine status, so the operator is informed through on-screen icons, rather than a simple audible or illuminated alert,” Hoover says. “This fully integrated self-leveling JLG boom moves the industry from simply getting to height, to now getting to and driving to height from one location to the next in the most efficient and productive way possible.”
Another benefit is that it provides operators a smoother, safer ride as they travel on the site. In a traditional boom lift, it doesn’t take much for operators or objects to bounce around when you’re at height — even pebbles on the ground can have an impact when elevated.
“The self-leveling chassis absorbs changes in the surface that you’re working on,” Ford says. “It provides a safe experience for that person who's in the platform.”
If it’s any indication just how much the operators favored these models, at one point on the L300 project, the 670SJs had to go back to JLG for some updates — and Ford heard about it right away.
“Almost immediately, the crews on the project started calling, asking when they could get them back,” he says.
Skanska has also used the 670SJs on the Hunts Point Peninsula interchange project in New York City and on the State Route 60 road widening project in hilly Southern California.
After initially putting several models to work, Skanska now owns them, and Ford says they’ve become an essential part of their fleet.
“For us heavy civil contractors that work in dynamic conditions with varying slopes and varying terrains, the 670SJ is important,” Ford says.
Saving Time and Money for Cianbro
All that the crews requested for a Maine substation project was a 60-ft straight boom lift.
When they tried the 670SJ, it exceeded their expectations, says Jeremy Moody, assistant project superintendent for Cianbro.
The contractor, headquartered in Pittsfield, Maine, used the 670SJ to install switches and above-grade electrical components as part of the Bowman Street substation expansion in Farmingdale. Cianbro handled the earthwork, concrete foundations, steel erection, and electrical work for the project.
It was the time- and cost-saving capabilities of the 670SJ that made the most impact, says Chad Burgess, dispatch supervisor for Cianbro.
“The amount of time this self-leveling feature saves is a huge asset to any fleet,” Burgess says. “Typically, if we need a lift on the back of an elevated site, we would need to have earthmoving equipment, such as — but not limited to — excavators, dump trucks, skid steers, or even rollers.”
He found that in most cases, the 670SJ curbs the renting or reassigning of additional equipment on the site for grading.
“This saves on permits, hiring trucks, the number of operators with special licenses, and countless other cost savings,” Burgess says.
As a result, it can radically change equipment planning and selection, as well as project timelines, he says.
Operators also reported the same comfort benefits that Skanska’s did, Moody says.
“They liked that when traveling, the platform wasn’t moving around,” he says.
Paired with its fully integrated, smart adapting steel chassis with self-leveling technology, the 670SJ offers three operation modes: self-leveling, standard travel, and shipping.
Self-leveling mode is the default option when driving the boom while elevated. Standard travel mode allows for max travel speed when the boom is in transport position and creep mode is off. In shipping mode, the chassis is lowered and boom functions are limited.
All operation modes are selectable and visible on the LCD screen, which also highlights capacity zones, fuel levels, and other information.
Not only does the smoother ride of the 670SJ cause less physical wear for operators and reduce the risk of dropped objects while the boom lift is traveling, but it also minimizes equipment contact.
“In a substation, our primary concern is preventing aerial platforms from contacting equipment,” Moody says. “When traveling, the JLG 670SJ keeps the platform stationary because of the self-leveling feature. This feature helps operators avoid unintentional equipment contact.”
Whether to rent or own a 670SJ would depend on the type of contractor and the work they do, Burgess says. But he sees a definite need for power and energy contractors in particular to purchase this machine for their fleets.
“Companies performing work in cities where one side of the machine needs to be on a sidewalk would also benefit from a self-leveling unit,” Burgess says. “The cost savings to the job are endless.”