There's been a transformation in hammer design from the inside out that makes these attachments simpler, smarter and easier to maintain, while increasing productivity and longevity. That's good news for contractors who rely on them to handle back-breaking work associated with demolition tasks such as splitting rocks and crushing concrete.
The evolution begins internally, with the advent of fewer moving parts in many new models. In some, you'll find as few as two moving parts. This offers benefits from several perspectives. For one, fewer moving parts mean fewer items that can ultimately fail. "The more moving parts you have, presumably the more seals you have around those parts and the more chances there are for things to go wrong," says Kevin Loomis, hydraulic applications manager at Atlas Copco.
"It also minimizes the high cost of the internal parts and the labor for rebuilding the hammers," adds Roland Jarl at Enterprising Europa, manufacturer of EEI-Socomec hammers.
Plus, moving parts feed off the energy transferred from the carrier. The greater the number of moving parts, the less energy that will be transferred and the less efficient, i.e., productive, the unit will be.
"Every moving part is moved by oil and energy from the carrier," Loomis explains. "Your ultimate goal is to transfer energy through the hammer to break rock. But the hammer will be less efficient when you're moving multiple parts internally."
In order to minimize the total number of parts, manufacturers evaluate every component and its function. For example, engineers at Allied Construction Products combined one bolt-on and two pin-on brackets into a single mounting bracket that allows the hammer to be adapted to any carrier or quick coupler. And instead of a series of steel bushings, the company's in-Series hammers feature just one bushing made of composite wear-resistant material, says Al Springer, national sales manager.
Bushings — and their maintenance — factored heavily into Ingersoll Rand's decision to eliminate tie-rods in its light-range hammers. "You have to torque them just right for the hammer to function properly," says Tom Pinchuk, attachments marketing manager at Ingersoll Rand. "And they're difficult to remove and replace."
In many cases, technicians were required to remove the tie rods, disassemble the breaker, pull out the bushing, measure it, replace it if necessary, then reassemble it. "It could take anywhere from four to eight hours to complete the process," Pinchuk says. "We've created a very easy system where technicians just undo a clip that surrounds the breaker and pull out the tool and bushing. The whole procedure takes three to four minutes. And you don't even need to remove the breaker from the carrier, which is especially beneficial if you have a dedicated breaker and carrier."
Many manufacturers are also moving to fully enclosed housings, or cradles, which also eliminate the need for tie rods, tie bolts and side bolts. "The totally enclosed casing eliminates the common bolt problems related to loose side bolts, as well as the wearing of the side plates," says Jarl.
This type of construction also protects the power cell and internal components, as well as reduces the amount of ambient noise created when the internal piston strikes the tool. "With just two side plates, the internal portion of the breaker is exposed to moisture and dust that can seriously impact wear," says Pinchuk. "These hammers are constantly being hit by rocks and flying debris, and they're used in narrow environments where they rub against abrasive surfaces. So it's imperative that we protect the hammer for an extended life."
At Atlas Copco, engineers design components to serve multiple functions whenever possible, says Loomis. For example, most hammers have an internal reciprocating piston that also serves as a battering ram. Typically, some type of control valve moves to direct the oil in the top or bottom of the piston to make the unit function. By removing the control valve and having the piston serve as a battering ram and a gate valve, engineers eliminated one component.