Rockster successfully established the first hybrid impact crusher
As the EU’s steadily declining limits for soot particles, nitrogen oxides and hydrocarbons for offroad machines, manufacturers of mobile plants are more and more requested to develop fuel consumption-, noise- and resource-saving technologies. Rockster has met the challenge and developed a completely new impact crusher for one of the largest French road construction companies.
R1100D becomes R1100DE
Rockster’s “duplexable” impact crusher R1100D served as the basis of the new machine. This crusher is known mainly for its robustness and its good performance with high crushing ratio of any material – from asphalt, concrete and demolition debris to hard virgin stone. The customer also wanted to increase its flexibility and ordered the preparation for DUPLEX, the patented system that allows switching from a jaw to an impact crusher (and vice versa) within a few hours. Thus, the system increases the ability to adapt to various customer needs and can process their orders more efficiently. However, to even enhance the efficiency of the machine to a maximum, the R&D department of Rockster developed a parallel hybrid solution in cooperation with a Finnish manufacturer of components. It is based on the electrification because, unlike diesel engines, electric motors deliver full torque from the state within milliseconds, handle load cicles more efficiently and allow a continuous, constant speed of the crushing unit regardless of the engine’s load condition.
Use of electrification as a hybrid solution
In the world of mobile crushers electricity is not often available, so Rockster has implemented the strengths of an electric motor in a hybrid solution. The diesel engine operates nearly constant at optimal speed to drive the generator for the electric motor. The permanent-magnet technology guarantees a decrease of energy consumption, a better engine- and generator-performance, and maximum performance density with lower weight and smaller components. Any load peaks are cushioned by condensers – so-called power caps – which buffer the energy. The fuel consumption is reduced and through the use of virtually maintenance-free electric motors also maintenance costs are minimized. With this technology you can save up to 60,000 liters of diesel annually.
Robust technology necessary
Due to frequent performance peaks and adverse environmental conditions in outdoor use Rockster placed high demands on the material used. All e-components are water cooled and meet the IP65 standard. They are specifically designed for usage in mobile construction machines and protected from dust, dirt and water. Moreover they are resistant to vibration and extreme temperature fluctuations.
The four new variable displacement pumps for the hydraulic system only supply the oil flow, which is actually needed, which reduces losses, saves fuel and ensures a consistently high pumping speed at low or varying diesel engine speed.
On the newly designed controller-display any machine parameters and settings are intuitive and easy to read. Carefully evaluated error messages increase a rapid determination and solution of failures and furthermore the ease of use increases the efficiency in the application and enrollment.
A hydraulic overload protection of the swing beams also improves the protection from inappropriate material and helps to avoid oversize material.
The unique return system, consisting of the two belt return or stockpile conveyor (known from Rockster’s R700S), is installed on one of Rockster’s bigger machines for the first time. With this system dismantling for transport is no longer necessary. You can work with a closed circuit and produce 100% definable final grain as well as the use it as stockpile conveyor with a discharge height of approximately 4 meters.
Optionally, the R1100DE can also be ordered with a grid connection to operate the crusher all-electric. So further savings are possible, but the electricity in off-road terrain is not always guaranteed.
By hydraulic cylinders on the screen box, it can be quickly and easily lowered for maintenance and exchange of the screens, also the connection and disconnection of the main belt is much easier.
Moreover the main conveyor can be quickly serviced or repaired by the new main conveyor belt service device. A permanently installed device carries the belt and keeps it in position, so you have easy access.
The optional main belt wear protection increases the life of the main belts significantly. The easily adjustable material protection forms a bed for deceleration and deflection of the material to be crushed, thus reducing the direct charge of the main belt.
Experience after 8 months of operation
Eurovia France Operations Manager Laurent Perraguin is highly satisfied with the new machine: “We produce 450 tons per hour of recycled demolition debris, that’s almost 30% more than we had before. With the hybrid solution, the performance is very consistent and the fuel needed could be reduced by 30%, so the investment for the newly developed plant was absolutely worth it, probably we will reach the ROI in not even 2 years.”
The Rockster team is convinced that important steps towards the future in technological advancements of mobile compact crushers are taken with this machine, and in addition technologies like this protect the environment and customers can save a lot of money.