The discharge hopper receives the aggregate from the belt conveyors and distributes it laterally in the hopper. The aggregate falls over two angular devices at the top of the discharge hopper, as seen in Figure 7‑31. Also in this photo is a scalping device. This can consist of either a series of bars or a coarse mesh to separate any large rocks, dirt clods, or weeds from the aggregate.

The hopper should be checked to ensure that it is clean and does not contain any aggregate particles from a previous project. The scalping grate should be checked to ensure that it covers the entire top of the hopper. This grate performs the very important function of keeping large clay balls and other foreign matter out of the fresh asphalt binder. Also, there should be no holes or cracks in the hopper, where aggregate can fall through and cause a ridge or row of excess aggregate.

The exterior of the discharge hopper should be checked for damage. Occasionally, a spreader will be driven over a large rock or other object damaging the lower front corners. Damage of this sort may be critical, because the roller bearings are held in a casing in this section of the hopper. Damage can cause the roller to wobble resulting in an uneven flow of aggregate.