7 high and low pressure pneumatic material handling systems consisting of blowers, feeders, pipes, elbows, cyclones, fans, airlocks, fittings, support structures, baghouse filters, explosion vents, abort gates, and spark detectors; and power driven material handling systems consisting of rollcases, chain transfers, and screw, belt, and chain conveyors, and bins, feeders and stackers, used in the building materials industry