New material flow concept as the key to higher performance
With the newly developed “EVO” generation of mo-bile impact crushers MR 110 (Fig. 1) and MR 130, Kleemann is setting new standards. “EVO” is a clear step forward with regard to performance, economic efficiency and wear behaviour.
So, for instance, the discharge chute under the crusher is 100 mm wider than the inner width of the crusher and the discharge belt which comes after this is a further 100 mm wider than the discharge chute. The material is thus transported quickly and carefully away from the critical area under the crusher. The flow rate increases and wear is reduced.
The independently vibrating effective double-decker grizzly contributes towards the impressive cost efficiency of the EVO plants thanks to improvements in the vibration behaviour of the screen and vibrating chute. Together with the newly designed crusher bypass which features changes to form and geometry, the entire system has been relieved of load and a significant contribution has been made not only to increased performance, but also the positive wear behaviour of the crusher. Another highlight is a new inlet geometry allowing for even better penetration of the material into the impact range of the rotor. Furthermore, the wear behaviour of the new C-form rotor ledges has been improved to such an extent that the edges remain sharper for longer, leading to an end-product of higher quality in the long run. The rotor ledges are held securely by a similarly new and user-friendly clamping system. This means that they can be changed even more quickly and thus contribute to the higher availability of the plant. With the newly developed fully hydraulic gap setting, it is not only possible to adjust the crushing gap with the electronic control unit, the zero-point can be calculated while the rotor is running. Manual opening of the crusher and positioning of the rotor and impact toggles are no longer necessary. Also worth mentioning is the new control unit which impresses with its significantly simpler operation, as well as the new rescreening unit. Not only simpler and faster to assemble and disassemble, this screening unit is now significantly bigger, by over 44 % with the MR 110 EVO. Only on such a scale can the considerably higher overall performance of approx. 350 t/h or 450 t/h (MR 110 EVO / MR 130 EVO) also be guaranteed during final screening.
Following a development phase lasting around one and a half years, trials with the first prototype began in late summer 2009. Already the very first test impressively showed that the overall concept was right on target. The first tests with the smaller of the two plants, the MR 110 EVO (Fig. 2), were conducted at a recycling centre near Kleemann’s main site in Göppingen. The feed material consisted of mixed concrete rubble from demolished material, initially still with a relatively low iron content. The feed sizes mainly consisted of particles with an edge length up to 600 mm, but larger particles were crushed in exceptional cases. In these cases, the remove-controlled lifting cover at the crusher inlet proved useful from the start. In the further course of the first test phase, the crusher was tested with a wide range of materials, including lots of demolition materials with a high content of iron, because here, as experience shows, the technology is exposed to very high stresses. It was shown that the plant could confirm the high capacity rates even in continuous operation. It became apparent that with the new material flow concept, wear at the key points such as impact bars or discharge belt could be decreased. The plant was tested at different customer operations to obtain feedback on the new operating concept from the different operators. This also ensured that a really wide range of feed materials was crushed. The other test stations included a company in Allgaeu. Here too, the plant was operated in many different applications and, thanks to the very “severe” winter (down
to -23 °C on many of the test days), could also be subjected to real “cold tests”. To start off, several thousand tonnes
of gravel were crushed, and then blocks of asphalt were processed, followed by reinforced concrete with varying
dirt content. In these tests, feed rates of 350 t/h were repeatedly achieved and even exceeded over relatively long periods.
The larger plant in the new series, the MR 130 EVO (Fig. 3), also underwent extensive testing. As this prototype went into operation some time later, here experience from the tests with the MR 110 could also be taken into account. Here too the potential of this plant could be quickly demonstrated: a maximum feed rate of 450 t/h was quickly realized and sometimes surpassed substantially.
After these tests with all standard applications – in one case even steelworks slag was processed – a very good cost balance could be obtained. As calculated in the theory, both plants demonstrated a very effective performance in terms of cost efficiency and wear. The new material flow concept not only effects a higher throughput rate, but also lower wear. The higher service lifetimes, in combination with a very efficiently operating direct drive, result in noticeable cost benefits on the operating costs side.
Kleemann GmbH, Göppingen (D),
Tel.: +49 7161 206-0, www.kleemann.info
