Hard Hitting Performance Wherever It's Needed MostAggregate & Mining Journal ,Volume 2, Number 2 When you ask almost anyone at Priestly Demolition for the secret of the company's success, the answer is simple and direct: Match the equipment to the unique requirements of the job at hand, large or small.
Among these hydraulic breakers are four units that were chosen from the TB Series of hydraulic breakers that is manufactured by Breaker Technology, Inc. (BTI) of Thornbury, Ontario. Priestly has chosen TB Series breakers in a number of sizes, ranging from the compact BTI TB285ME in the 750 Mb (1,016 Nm) class, all the way up to the BTI TB2580X in the 13,500 Mb (18,300 Nm) class. Not too long ago, Priestly expanded his breaker arsenal so he could work on a $20 million demolition project at the Toronto Pearson International Airport. It was a massive undertaking that netted the company a Toronto Construction Association innovation award in 2004. Tips on choosing the right breaker for the job More recently, Priestly chose one of his BTI breakers-the TB2580X-for use on a rock-breaking project that was being conducted on the future site of a major, upscale residential resort community. The project involved the excavation of 2.5 mi (4 km) of trenching for water and sewer lines. The trenches were to be 8 ft. (2.4 m) deep and 3 ft. (0.9 m) wide. The general contractor had expected mainly dirt and clay during the excavation, but he had hit what Priestly referred to as quarry stone. Priestly Demolition was called in as a subcontractor to break the rock. Priestly mounted the BTI TB2580X on a Link-Belt 5800 Quantum Series excavator in the 50-ton (45-tonne) class. "We chose this equipment for the project because we felt that bigger would be better," Priestly said, explaining that there is less consistency when breaking rock versus concrete. "Once you start breaking concrete, you know how hard it's going to be. But rock can be soft one minute and hard the next. So a bigger hammer would give us more production, at a desired rate, and would not be slowed by harder rock." Priestly added that the larger breaker will break the rock with fewer blows because it is hitting harder with each blow. A higher repetition hammer, he said, will often bounce right off the rock. According to a spokesman for BTI, the company's engineers agree with the choice of the larger breaker in this application. The BTI TB2580X delivers longer piston strokes, creating more energy per blow but with less frequency. Alternatively, a shorter piston stroke results in more blows per minute but with less energy per blow. When breaking hard material such as rock, impact power is of primary importance. On the other hand, the striking rate is more important when breaking softer material, such as in lighter duty concrete applications. In addition, BTI engineers recommend that the breaker should be large enough to quickly break the material, without drilling through it as might happen with concrete. Also, the breaker should be sized according to the carrier: It should be small enough to not overwork the carrier, but large enough not to be damaged by the carrier's weight. It is also considered important that the carrier's hydraulic system meets the breaker flow-and-pressure requirements. Although breaker performance is significantly affected by choosing the correct hammer for the application, breaker design elements also play a part. BTI engineers point to the fact that the company's TB Series breakers contain only two moving parts, which means fewer parts are subject to wear. According to BTI specifications, the company also uses a low-pressure nitrogen-gas chamber to absorb piston recoil, throttle orificing to protect the carrier from pressure pulsations, and an anti-blank firing mechanism to prevent the piston from contacting the tool when it is not against the material to be broken. Job experience is necessary in a breaker operation
The equipment is ready to meet future demand In the autumn of 2005, Priestly Demolition moved its BTI TB2580X breaker to yet another rock-breaking project along Ontario's Highway 26. The company is acting as a subcontractor for one of Canada's largest construction and infrastructure development companies. The project involves removing rock to allow for the construction of new passing lanes. The breaker is still mounted on the Link-Belt 5800 excavator. "We have five Link-Belt excavators and we will continue to move the breaker from one to another," said Priestly. "If we have a job that is three hours away, we can just send the hammer in a smaller truck. The operator can easily change out the attachments in only about 15 minutes. With so many different applications, and such a wide range of carriers and attachments on the market, choosing the most efficient tool for the task can be an difficult challenge. For Priestly, he feels that no matter what options are available, he will always lean toward the best support and service. "With my four BTI breakers," Priestly said, "I can take on about anything that comes my way."
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