Professional natural stone processing

As a specialist in the cement, gravel and natural stone industry, Heinrich Hecker KG from Anröchte in North Rhine-Westphalia attaches huge importance to the use of state-of-the-art high-performance machines. For operation in different quarries, the family enterprise therefore decided to acquire two mobile impact crusher plants MOBIREX MR 130 Z EVO2 from Kleemann GmbH.

Heinrich Hecker KG was founded in the 1950s and has a machine fleet of 100 different vehicles and plants. Since 2011 Hecker has been active as a crushing contractor in natural stone. When the award for new projects for the extraction of material for road construction arrived, the company decided to purchase two new crushing plants. "We work at changing sites and rapid excavation progress means that we have to move the plant on a regular basis", says Nicole Menzel, Office Manager at Hecker KG. "This is why we looked for a mobile impact crusher plant that is particularly easy to transport and can be used flexibly. After careful consideration we chose the MR 130 Z EVO2." Thanks to the hydraulically folding hopper walls the plant can be prepared and loaded for transportation in less than an hour.

The two machines are currently deployed in two quarries for the extraction of andesite and diabase. The challenge here lies in the high abrasiveness of the feed material. From the outset it was clear that the rotor ledges, in particular, would be subject to a high level of wear. "The rotor ledges are replaced after 500 operating hours when extracting hard natural stone such as andesite", states Nicole Menzel. It is possible to replace the rotor ledges quickly and safely with the innovative Lock & Turn system. A clever key system ensures that the user only has access to the rotor when all safety steps have been performed. Then the rotor can be locked in any desired position simply and safely. The replacement of the rotor ledges is thus possible within 45 minutes, which significantly reduces the downtimes.

During the processing of andesite the feed material is on average 0 to 600 millimetres in size and is processed to a final end product of between 0 and 45 millimetres, which is then used as a base layer in road construction. In order to guarantee the high performance and long service life of the plants, Hecker services its crushers on a daily basis. As a result, any changes to the wear parts of the machines can be identified and eliminated in good time. In the event of difficulties, the Kleemann service team from the Wirtgen Group subsidiary in Windhagen is on site at short notice and guarantees the quick availability of spare parts.

An MR 130 Z EVO2 is also used for extracting diabase. The material is less abrasive than andesite, is easier to crush, meaning the rotor ledges only need to be replaced after 1,000 operating hours. Depending on the requirements of the customer, the plant produces frost-proof material for use in road construction, for example in the sizes 0 to 32 or 0 to 45 millimetres. Owing to the high proportion of fines, the MR 130 Z EVO2 is also offered with an independent double-deck prescreen, as this ensures effective prescreening, which leads to less wear and higher final product quality.

Another advantage of the MR 130 Z EVO2 is the infinitely variable crushing gap. Thanks to the hydraulic adjustment the gap can be adapted during an ongoing operation without long downtimes. As the material flow through the plant becomes wider, the stone can be processed more efficiently. The Continuous Feed System also ensures higher productivity and can slow down the material transport of the vibrating feeder and the prescreen depending on the fill level of the crusher and accelerate it again. As a result, an optimal crusher feed is guaranteed.