High Potential for Metso Diablo Pre-Shredder
In the course of a continuous further development of recycling technologies, Metso took over the pre-shredder business from the Italian company C&G in 2010. The brand name Diablo has a long tradition and is very well known in the market. This robust machine has demonstrated its high performance and reliability in almost 30 installations worldwide.
A pre-shredder is generally used in ferrous scrap yards to produce a homogeneous feed size of the material, which is then processed in a hammer mill in a second work cycle. It is particularly useful for processing car bodies and baled light scrap to ensure a uniform shredding process.
The new Metso Diablo Pre-Shredder is available in two housing sizes with a feeding width of 2100 and 2500 mm. The smaller pre-shredder is driven by a hydraulic unit with 405 kW, the larger one can be optionally equipped with 510 kW or 632 kW.
The proven and reliable working principle of the fully automatically operating Diablo is based on the interaction of two rotors and a flipper.
The top rotor and bottom rotors are independently driven by low-speed, high-torque hydraulic motors mounted on each rotor shaft. The combined action of high torque and a constant speed ratio (approx. 1:4) between the counter-rotating rotors allows the meshing teeth of the star discs to tear the scrap apart. In case of an overload, if the hydraulic system reaches the maximum torque, the rotors switch to a lower speed and reverse. At the same time, the flipper is actuated and compresses the scrap against the top rotor. The flipper remains in an intermediate position until the overload condition has been resolved.
The housing is tiltable for easy maintenance access. This feature is, indeed, rarely used due to the fact that the rotors including the star discs and the flipper as well as the whole crushing chamber are designed for a long service life.
Operators who have run the Diablo for many years state that they are very satisfied with the easy maintenance, the high availability and the corresponding low maintenance costs. The main wear is on the star discs of the rotors, which have to be built up after approx. 6 000 hours of operation. This is an outstandingly low figure taking into account the extremely high operational demands.
The use of a pre-shredder ensures the best possible separation as well as more flexibility in terms of the feed material which leads to an optimized utilization of the shredder installation. Furthermore unshreddable or risky material can already be detected in the first process step.
Metso will deliver the first pre-shredder, the Metso Diablo model DH 216, to SIRMET, a well-known French metal recycling company with approximately 35 employees and four sites. The machine will be installed near Angoulême in France in September 2011.
With its around 550 machines and plants built to shred scrap metal, Metso Lindemann is one of the world's leading manufacturers of recycling systems. 44 years ago, the company delivered its first shredder. For almost 100 years, the company has been developing, designing and manufacturing in Düsseldorf. The major products on offer include scrap shears, scrap balers and briquetting presses.