machines for sifting, grading, sorting and separating flowable materials which can be delivered in a cascade or stream by size, shape and/or color, namely, rice, coffee beans, whole fruits and vegetables and fruit and vegetable pieces, raw, partly cooked and cooked products, wood chips, particulate minerals, recycled solids such as glass and metal fragments; conveyors and elevators used to transport material sifted, graded, sorted and separated by the above-referenced machines; pneumatic ejec...