Rock Breakers Cracking The Surface
- Published: Saturday, 01 August 2009 08:00
Unlike the constant rap of a secondary breaker pulverizing boulders, this tool segment has seen a quiet year. Not much has been developed, as most companies
Unlike the constant rap of a secondary breaker pulverizing boulders, this tool segment has seen a quiet year. Not much has been developed, as most companies are taking time to breathe after Conexpo-Con/Agg or sell inventories in a poor economy. However, there are at least two companies with new offerings: Atlas Copco and BTI.
TWO NEW DEVELOPMENTS IN SERVICE AND TECHNOLOGY
The MB 750 from Atlas Copco is a medium-duty hydraulic breaker. Its service weight is 1,654 pounds, and it delivers 370 to 800 blows per minute. Tool diameter is 3.9 inches. It is powered by a combination of oil and gas, and recovers energy by maximizing the recoil effect. This boosts the output power of the breaker without increasing the hydraulic input power of the carrier, which results in less fuel consumption during operation, the company says.
The MB 750 operates at 118 decibels because its percussion mechanism is acoustically isolated from the external guide system. Another feature is the double retainer bar system. The company says that the longer retainer bars provide additional contact surface so the tool can be used on both sides for extended service life. Double retainer bars offer higher wear resistance than a retainer pin and are a locking system for the locking pins.
The MB 750 also has a two-stage sealing system with coarse and fine strippers that prevents abrasive dust from penetrating the lower section of the breaker. It keeps the lubricant around the wear bushing for a longer period of time. The system reduces wear on the bushings and the hammer and protects against damage.
Also, Atlas Copco has extended the warranty for light and medium hydraulic breakers to three years. The program offer is for all SB and MB range hydraulic breakers purchased after July 1. It includes unlimited operating hours. The warranty covers the breaker's main components including the piston.
The BTI BXR160 at 16,000 ft-lbs, is designed for continuous duty. Its working weight is 12,000 pounds. Tool diameter is 8 inches. Flow range is 85 to 120 gallons per minute, and operating pressure is 2,030 to 2,755 psi, which delivers 260 to 425 blows per minute in long-stroke mode or 340 to 530 in short-stroke mode. The company says, it offers an extra long stroke design, which improves the power-to-weight ratio of the breaker, providing the widest carrier range (120,000 to 220,000 pounds) and power available. Large cross section upper and lower shock-absorbing isolators reduce vibration feedback to the carrier. BTI's front head restraint system tightly guides the front head within the housing, reducing loading to the tie rods and the upper portion of the breaker. A narrow box housing design is well suited to tight trenching conditions.