PROBLEM AREAS
In this article we would like to individually address each of those areas and explaining how we can reduce or minimize segregation you may experience in your lay down operation.

THE HOPPER - AREA 1
This area is most critical when using end dumps, dump trailers, or horizontal discharge units. The exchange of hauling units presents the greatest challenge in this area. Care should be exercised when exchanging trucks, to never allow the hopper to run completely empty revealing the conveyor system components. In fact the hopper should never be allowed to have less than 30% capacity at any one time during the exchange of trucks. If the hauling units have not been loaded properly or the discharge procedures of discharging the material in a mass are not followed correctly then the segregation in the hopper will be compounded. Hauling units should be loaded in three or more dumps, loads broken before the tailgate is released and a continuous flow of material from opening tailgate to completion of discharge is essential to present to the paver hopper with an homogenous blend of material to be laid. If the material is presented to the hopper in a blended condition it should not be allowed to segregate in the hopper. The outside corners of the hopper are places to observe.

These areas of segregation can best be addressed by proper folding of the hoppers between loads. How and when do you fold the hoppers? Some today advocate never folding the hoppers and this area will fill with dead material and remain until cleaned out when paving is discontinued. This becomes quite a work intensive effort and could be minimized by adding steel plates in the area where cold mix is removed reducing the effort needed to clean out this area each time you cease paving. A suggestion on folding hoppers might eliminate this area of concern. First only fold the hoppers enough to keep the material live and hot enough for laying. Once the hauling unit exits the paver, begin raising the hoppers steadily while the paver is still moving forward. Continue forward movement of the paver, raising the hoppers until the material clears the outside corners, leaving ample material covering the conveyor components. Lower the hoppers and prepare for the next load, keeping any paver stops to a minimum. If this is done properly the area should not be a problem.

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