One machine for screening, mixing and the production of flowable fill
Published 4/3 at 11:32The Backers wheel and/or track mobile star screen can also operate as a mixing machine. It can screen in three fractions as well as stabilise soil and further produce flowable fill (CLSM).
The Starscreen 3-mtb has a coarse and a fine screening deck. It screens first coarse and then fines into three fractions. The hopper can additionally be fitted with a grizzly screen to separate big stones and loosen up the sticky soil.
The star screen can also be used as a screening and mixing machine. Instead of the second, fine screening deck, the fitting for mixing comprises of a compound box and can thus produce stabilised soil. To produce stabilised soil from sticky material, the coarse star deck should screen out the 60mm material. The coarse screen loosens up the soil (0- 60mm) during screening, whilst the under belt sees the throughput measured with a weight installation. The compound (1-8%) from the compound box is then mixed into the soil, whilst some soil agglomerates get finer with a rotating hammermill. The capacity can be about 200t/h. It is also possible to screen the soil finer, directly when the mixed soil leaves the mixing machine. The silo of the screening and mixing machine is filled from a separate silo. The air pressure for the pump is produced from the star screen in this case.
The ‘Canbus’ steering on the Starscreen 3-mtb steers soil, compound and water of each stage of the concrete mixer. The concrete mixing truck is deeper, so it is filled directly from the screening and mixing machine. The flowable fill should get to its destination after between 15min and 90min. The screening and mixing machine is best fitted with an extra belt to fill directly into a concrete mixer truck. The extra belt is driven by the hydraulics of star screen.
The star screen moves the mixed soil and the water flow into the concrete mixer truck, whilst the mobile screening and mixing system is used for the tapping point. The time between producing the flowable fill and filling it at the destination is short and easily plannable. It can be controlled easily. Six concrete mixer trucks can be filled in one hour by the produce of flowable fill.