Steve Skinner reports on a move to quieter, more carrier-friendly hydraulic breakers

While there's an underlying trend for bigger and more powerful hydraulic breakers, there is also a move towards quieter, more carrier-friendly systems. Steve Skinner reports on developments to enhance working environments for operators and extend equipment lifecycles for owners.

The very nature of breakers is that they have to create, and therefore withstand, hundreds of significant and repetitive impacts every minute. Size and weight have a huge influence on the creation and absorption of vibrations and this continues to be the case as can be seen with many of the latest launches.

Tabe's new AGB-40 hydraulic breaker is one of the new generation heavyweight breakers. Weighing 4.8 tonnes and designed for use with excavators of between 45 tonnes and 70 tonnes, the AGB-40 is the first breaker to have been tested at Spain's Aragón Institute of Technology (AIT) - one of the few research centres with facilities physically capable of testing equipment up to 6.6 m in height.

With a tool weight of 385 kg and tool diameter of 210 mm, the AGB-40 will make its debut appearance at April's Bauma exhibition.

"We have maintained our market position through constant innovation and exhaustive quality control," said a Tabe Spokesman. "In this respect we believe the AGB-40 will be among the most eagerly anticipated new products this year," he said.

Indeco's 11 tonne HP18000 hydraulic breaker was launched back in 2008, and the Marocca Group in Italy was one of the first quarry operators to invest in the heavyweight unit, which it fitted to its 120 tonne Hitachi 1200 excavator via a Lenhoff quick coupler.

Group president, Alberto Marocca said, "The excavator coupled with the HP18000 breaker does the work of two mid-sized machines and manages to reduce the size of the hardest blocks without any problem.

"Furthermore, the HP18000 has enabled us to adopt a more rational use of explosives, which has helped us to increase production while making major cost savings."

Mr Marocca believes advantages can be gained in terms of production, costs and quality through the use of large-sized breakers. "The breaker can guarantee continuous production, whereas using explosives requires long downtimes," he said.

"While not eliminating the need for explosives altogether, the use of large breakers such as the HP18000 does reduce the need by a large margin," he said.

Stress relief

Indeco's new anti blank firing system (ABF) has been designed to increase the service life of all components subject to wear and tear in a breaker.

Now installed as standard on all its breakers from the 104 kg HP-200 to the 7.8 tonne HP16000, ABF eliminates blank firing through the eradication of down pressure whenever the breaker tool is not resting firmly on the surface to be broken. "Through the use of ABF we've been able to reduce stress on both the breaker body and the excavator arm," said a spokesperson.

Breaking Technology Inc. (BTI) has introduced large cross section shock absorbing isolators mounted in the upper and lower sections of its BXR series of breakers to reduce vibration feedback to the carrier unit.

Director of international sales, Robert McArthur said, "In expanding the BXR series to include five new models in the 6780 Nm to 16275 Nm power range we considered it imperative to reduce vibration feedback to the excavator.

"Precise tolerances between the piston and cylinder provide high efficiency and power as well as a fast blow rate, while a restraint system guides the front head within the housing, thus reducing the loads on the tie rods and upper portions of the breaker unit," he said.

Atlas Copco will launch its 3.1 tonne HB311 breaker for carriers in the 30 tonne to 52 tonne class at the Bauma exhibition. The new breaker features a range of design modifications and integrated systems to protect it and the carrier while maintaining efficiency and productivity.

Alongside an optimised box design, the HB311 is fitted with PowerAdapt, a system that shuts down the breaker in the event of high oil pressure.

Product line manager for medium and heavy breakers, Torsten Treger said, "Hydraulic breakers can be overloaded if the carrier's oil pressure has the wrong setting. Conventional pressure relief valves drain oil back into the tank which wastes energy and effects efficiency. With the PowerAdapt system an operator can make full use of his equipment's efficiency and power."

The HB311 also features a new retaining bar to provide improved protection for the lower section of the breaker which faces the most wear and tear.

As with all of its heavy-duty hydraulic breakers, the HB311 is also fitted with Atlas Copco's VibroSilenced system to protect the operator from noise and vibrations.

Last summer Sandvik unveiled two new breakers for the global market featuring noise and vibration damping, and sound suppression systems.

The BR2155 for carriers in the 16 tonne to 26 tonne range has a working weight of 1.2 tonnes and an impact rate of between 490 and 780 blows per minute, while the mid-range BR2577 for carriers in the 23 tonne to 28 tonne range weighs 1.7 tonnes and features an impact rate of between 450 and 750 blows per minute.

In standard specification, both breakers feature Sandvik's vibration damping system (VIDAT) and improved piston seals to prevent oil leakage. Options include a safety valve to prevent oil over flow, automatic greasing for the valve head and wear plates to protect the casing.

Demolition and recycling segment manager for the UK and Ireland, Alan Matchett told iC, "When developing these breakers we wanted them to be quiet, easy to maintain, environmentally friendly, user friendly and with a good service life. I think we've achieved that aim."

Montabert's new Blue Line breakers incorporate a hydraulic and mechanical auto stop system to extend the life expectancy of the breakers. The combined system protects against blank firing via a damping system that's active from the first blow.

The 1.7 tonne XL1700 is the first breaker in this entry level range, which has been designed for high performance and efficiency as well as durability and ease of servicing.

The main valve and the nitrogen chamber accumulator control the movements of the piston, increasing performance and efficiency through the optimisation of the breaker's strike power. Meanwhile, the energy recovery system increases the strike power by using the energy generated by the piston rebound.

"This system allows an automatic increase of the breaker's frequency when used on hard materials," said the spokesman.

Doosan's new DXB range of hydraulic breakers featuring the DXB170, DXB190 and DXB260 units for use with carriers from mini-excavators and skid-steer loaders through to large excavators has been designed to be robust, economical and reliable while offering carrier protection and operator comfort.

"DXB technology ensures the carrier is protected through a reduction in pressure peaks," said a spokesman. "The breakers in the new range are fitted with an energy recovery and valve system to increase performance, a high quality piston and cylinder manufactured to precise tolerances to lower maintenance costs and an advanced dampening system to protect against blank firing," he said.

Following the Bauma exhibition, Doosan will launch a 900 kg DXB100 for excavators in the 10 tonne to 20 tonne class with blow energy of 2350 J and a blow frequency of up to 800 blows per minute.

Furukawa Rock Drill, in cooperation with the Technical University of Tokyo, has developed a new range of FX breakers for mini excavators of between 0.5 tonnes and 7 tonnes. Featuring an impact mechanism that reduces noise and minimises the discharge of vibration to the carrier unit, the new line of breakers also dramatically reduces vibration stress for the operator according to the company.

"With its fully closed frame featuring rubber-plugged service points and a redesigned rod arrangement, the FX series offers noise reductions of up to 7 db, which represents a considerable decrease," said a spokesman.

Environment

While large scale heavyweight breakers have the scope to alter working patterns and reduce costs in certain applications, the demand for more carrier and operator-friendly units that are quieter is increasing.

Durability of equipment, both in terms of the breaker and its carrier unit, is also an important driver. Future breakers will have to be rugged and offer superior productivity on the one hand while being gentle and sensitive on the other. A tough ask, but one that manufacturers are now addressing.