The Mechanical Handling and Storing of Material

ELE VATO RS FOR MATERIAL IN BULK x9 An elevator with one or more upper terminals and two lower terminals is shown in Big. 14. In addition to special delivery facilities, it has the peculiar attribute of being capable of conveying horizontally between the two lower terminals, but whether it has one or two top terminals it can only deliver at that point where the chain of buckets traverse the first top terminal. The delivery is unlike that of other elevators, being towards the terminal instead of away from it. In order, therefore, to get a clear delivery the top sprockets are fitted with five plates, filling the space between the two sprocket wheels, and thereby forming revolving delivery shoots, each of which receives the contents of two buckets and leads the material into the delivery shoot proper. Continuous Bucket Elevators.—A very economical form of elevator is one fitted with a continuous chain of buckets. This kind is naturally of a much larger capacity than an ordinary elevator of the same dimensions. It takes and delivers its load with more uniformity, and as the buckets need not plough intermittently through the ■contents of the elevator well, smoother running is secured. Fig. 15 shows such an elevator for grain, and Fig. 16 for minerals. 1 he table on the next page gives dimensions of continuous elevator buckets for grain and their capacities in tons per hour at varying speeds. Elevators for Coke.—The buckets used for coke elevators should be of malleable castings with strengthened lips. They should have skidder bars rather than rollers fixed to the axles, running on the angle iron forming the framework of the elevator on the upward and downward paths. The buckets should also be placed nearer each other