New Volvo HB2400 Low Noise hammer makes quick work of New England boulders.
Easthampton, MA - "There are 1,000 big boulders here, not solid ledge," says David Dietz, president of Dietz Construction Corp. He's talking about the five-acre site his company is preparing for the East Hampshire District Courthouse in Belchertown, MA.
"It's a conglomeration of rocks, mostly granite, and the boulders range up to 16 feet in diameter," says Dietz. "It's more efficient to hammer it than to blast it. Breaking and excavating the rock here is our biggest challenge."
It's a challenge that Dietz and his crews are meeting quite handily. He figures it will take just eight weeks to break and excavate the site's 8,000 cubic yards of rock. "All the rock is being broken to 30 inches and smaller," says Dietz, whose company is based in Easthampton, MA. As well, approximately 10,000 cubic yards of earth will be excavated to remain on site.
His hammer of choice is the new Volvo HB2400 Low Noise model, mounted on a Volvo EC240B LC excavator. The 7,000-ft.-lb. hammer - introduced less than a year ago - is working very well in the hard New England granite, Dietz says. "We've used hammers from three other manufacturers, and this one works much better than those older models," Dietz says. "It's a quieter operating hammer and gives less vibration to the operator."
Hammer operator Mike Gregoire likes the rig as well. "That hammer is perfectly sized to the excavator," he says. "It's stable, well balanced, and doesn't make much noise. You can extend the boom all the way out and it won't tip the machine."
Ahead of schedule
Thanks to unseasonably warm temperatures, the company has worked the project through December and January - months normally too cold to work in New England. But this year, the ground is not even frozen. Originally the project was to shut down during the winter, Dietz said, but work began in October and will wrap up in June, well ahead of schedule.
When we visited the project, Dietz was using an EC290B LC to load out seven tandem-axle trucks. Meanwhile one EC240B LC traded between hammering boulders and feeding broken rock to the larger excavator. A second EC240B LC was digging foundations and handling utility work.
Dietz prefers Volvo excavators, and owns eight of them. "Our last five new excavators have been Volvos," he says. "We like the production of our Volvo excavators. We've found them to be very strong and capable machines for rock excavation. The quick coupler system and hydraulics work well for changing buckets and attachments quickly, including the hammer." It takes just about five minutes to drop a bucket and mount the hammer, as we observed on site.