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Damp and cohesive feed material clogs your pre-screen and slows down production

Your wear costs are through the roof because you can't keep your pre-screen open? The patented RM Active Grid keeps the grizzly unplugged so that you can maintain low operating costs throughout the day.


High levels of fine material in the crushing box reduce the efficiency and profitability of the crusher

Mixed C&D waste, excavated materials, and sand & gravel are just a few examples of materials with a high fines content. If not prescreened properly fine particles entering the crusher cause unnecessary wear on hammers (also called blow bars) and wear plates. Fines inside a crusher box is like sandblasting wear components, which requires you to replace them more frequently. Using a pre-screen reduces the amount of fines going into the crusher so that you can increase your production and improve your bottom line.


Conventional crusher grizzly screens tend to clog up

For this reason, in many cases a crusher prescreen grizzly is used for bypassing fines. So far so good, except that the grizzly has the disadvantage that due to its rigid construction it clogs up over time, especially with damp, sticky or loamy, cohesive material, reducing its pre-screening efficiency. Even with dry material, the screening rate is often not ideal. This again causes most of the material to enter the crushing box, or block the inlet to the crushing box, slowing down the flow of material. This has the effect of reducing the crusher throughput, increasing wear and requiring the crusher to stop so that the bar mesh can be cleaned. 


Patented RM Active Grid

The smart solution for highly efficient pre-screening

RUBBLE MASTER developed the RM Active Grid to solve the problems described above. It consists of rigid and movable sections of bar mesh that feature a special configuration. The vibration of the vibro-channel causes the Active Grid to oscillate, so it does not need its own drive system. The active vibration of one section of the bar mesh significantly increases the screening performance and, depending on the material and the type of job, increases the total material throughput by up to 30%. Efficiency is also increased thanks to the self-cleaning effect of the Active Grid, ensuring consistent screening performance. The fine material can then bypass the crushing box onto the main discharge belt, or be discharged on a side discharge belt.  The result: more material throughput, less wear, lower costs and longer maintenance intervals, which ultimately adds up to more productivity and profitability. If pre-screening is not required because the crusher is being used for a different application, the RM Active Grid can also be fitted with a subfloor, which is quickly installed.

Other Pre-Screening Options

Because processing requirements vary greatly from one job to another, RUBBLE MASTER naturally offers a range of solutions for pre-screening. In addition to the RM Active Grid and a standard bar mesh, a 2-deck pre-screen integrated into the feed belt is also offered for defined feed material particle sizes. RM also offers the HS series of mobile scalping screens, which are available in a range of sizes. 

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