The first two terms on the right-hand side of the equation represent the power
necessary to move the load horizontally, while the third term represents vertical
movement. The last term represents power loss due to friction. Although the units
in this equation are obviously spurious, the constants in the denominators are used
to convert everything to power.
For specific materials, empirical evidence suggests some maximum loadings on
conveyor belts without skirts, as shown in Table 5-1. These capacities are for a belt
with a 20º trough (angle of the edge of the belt with the horizontal), as shown in
Figure 5-3, and a belt speed of 100 ft/min (30.5 m/min).
Live bottom hoppers are related to vibrating feeders and are used to move MSW
out of holding bins or transfer trailers. As the name implies, the bottom of the hopper
has sliding interlocking beams that move at set speeds. By moving them slowly forward
and then rapidly backward, the motion slowly moves the burden forward. Live bottom
feeders have been installed in facilities where refuse has to be moved a short distance
such as in transfer stations. Figure 5-4 is an illustration of a typical live bottom feeder.