TOUGH ROCK, STOUT HAMMER

The extremely hard rock that Gorham Sand & Gravel must break up and remove from its job sites gets so hot while being pounded by a hydraulic hammer that any grease that drips from the attachment starts on fire when it hits the rock. These extreme conditions on Gorham’s underground construction jobs might leave you wondering what gets more punishment – the rock or the hammer. As company co-owner Jim Shaw found out when his hammer went down, you just need the right brand. So he turned to a Volvo HB3800 hammer.

“It’s a lot faster. It hits a lot harder,” said Shaw, who runs one of the top construction firms in Maine. “It’s quieter. It doesn’t take nearly as long to do the same job as the other hammer did. We really like it.”

Gorham Sand & Gravel’s previous 12,000 pound hydraulic hammer burned out while working in the company’s quarry operations. With an important drainage job upcoming at the Portland International Jetport, Shaw knew he couldn’t afford downtime with his hammer. So he turned to Chadwick-BaRoss Inc., the Volvo Construction Equipment dealer in Portland that had just put 12 new Volvo hammers into its rental fleet.

At first, Shaw rented the Volvo HB3800 hammer, which delivers force of 12,000 pounds per foot. It didn’t take long to decide to buy it. “It has been night and day, the Volvo hammer vs. the other hammer,” Shaw said. “It has performed very, very well.”

Shaw has seen his company grow from just he and his brother Tom 20 years ago to a recognized leader in southern Maine with revenues in excess of $15 million a year. Part of that success has been and setting the trends instead of reacting to them.

Volvo vs. blue Maine granite

The first job the hammer went on was installation of a drainage system for a new 1,000-space parking garage at the Portland airport. Gorham Sand & Gravel needed to lay 18-inch storm drain 28 feet below grade. After excavating 9 feet of overburden, Shaw’s crews had to dig out between 18 and 21 feet of solid Maine granite, along a 300-foot-long trench.

“It’s a hard, blue-gray rock,” Shaw said. “It’s almost like glass. It breaks up like glass. It’s the hardest stuff we’ve ever worked with.”

Because the rock was so dense, simply using a hammer would not fracture it. Crews first had to drill 6 foot deep pilot holes in the granite to create a “Swiss cheese” pattern. Then the Volvo HB3800 was brought it to break up the ledge. Every 2 feet or so, an excavator would dig out and remove the broken rock, and then the process would start over.

The process is time consuming, and extremely hard on the equipment. Normally, the bit on a hydraulic hammer will last several months, but on these kind of job sites the bits wear out in less than two weeks.

“We’ve broken quite a few bits,” Shaw said. “We’re down in the virgin ledge. It’s hard to break. It’s solid all the way through. There’s no relief, except for the holes we drill.”

The Volvo hammer allowed Gorham Sand & Gravel to get a head start on the Portland airport project while the company was getting regulatory approval to do blasting at the site. Of the 300 linear feet on the drainage project, the Volvo hammer processed about 120 feet before the company was able to blast the rest.

“If we could have blasted, it probably would have been a two and a half week job,” Shaw said. “We couldn’t blast, so it turned into two and a half months. We were hammering between eight and 10 hours a day out of a 12-hour work day. Seven days a week.”

Durability and production
Shaw said because the hammer gets nearly constant use, durability is a key issue. The Volvo hammer gets good grades for durability and performance.

“On a pipe job, if the hammer’s not working, the crew’s not working,” he said. “A lot of times, if we can, we’ll keep the hammer working all night so when the crew gets there in the morning they have something to do.”

The Volvo HB3800 has also been used on a road construction job near Buxton, Maine, where Gorham Sand & Gravel is doing full-depth reconstruction with storm drains, gravel, new asphalt plus ditches, sidewalks and curbs. The rock is not as deep, but the trench stretches over two miles. Shaw said on these types of jobs, production and speed are keys

“We can average between two and four hundred feet of pipe in a day,” Shaw said. “We want that hammer at least a day or two ahead of it. On a lot of our shallow pipe, we’ll go in first and hammer it, and then send the pipe crew in after. So we don’t have to wait for the hydraulic hammer to do its job.”

Volvo’s low-noise design is a big advantage, Shaw said, especially on urban job sites where equipment noise levels are strictly regulated and monitored. The Volvo HB3800 is substantially quieter than others hammers the company has used.

“It’s a lot quieter,” Shaw said. “Probably a third less. It’s about the same as our 5,000-pound hammer in terms of noise. That’s a big issue. If they come out with the decibel meter and you’re over the levels, you can’t use the hammer. But the Volvo hammer is compliant even with the strict Portland noise standard.”

Auto lube, S-type coupler
Gorham Sand & Gravel decided to outfit the Volvo HB3800 hammer with an auto-lube system, utilizing the hammer’s built-in grease channel. The auto-lube system ensures the hammer gets fresh grease at assigned intervals and will ensure longer equipment life, Shaw said.

Chadwick-BaRoss suggested Gorham Sand & Gravel outfit its excavators with Volvo S-type couplers, which allow Volvo hammers to be fitted to any brand of excavator and make it easy to swap out a bucket for a hammer or other attachment. Shaw said he’s a believer in the S-type coupler.

“The operator can stay in the cab and swap buckets,” he said. “It saves a lot of time. We have four or five excavators and we can easily swap buckets between them. We do this a lot more often than we used to.”

HAMMERS: GOOD RENTAL ITEMS

Gary Thebarge is such a believer in hydraulic hammers, he put 12 new Volvo breakers in his equipment-rental fleet.

“We do quite a bit of hammer rental,” said Thebarge, vice president of Chadwick-BaRoss Inc., a Volvo Construction Equipment dealer that covers Maine, Massachusetts and New Hampshire. “It’s an excellent rental item. Hammers especially seem to get rented down and then get sold. Contractors prefer to rent them first and then look a good price point to buy them.”

Mike Sullivan, general manager of the Chadwick-BaRoss location in Westbrook, Maine, said Volvo’s new line of hydraulic breakers will become an industry leader for toughness, reliability and quiet operation.

“As the word gets out on Volvo hammers, the potential will only increase,” Sullivan said. “Having them in our rental fleet is going to be very good for the hammer business.”

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