Atlanta standard worm drives are manufactured from well- proven materials. The worm is of steel and has hardened and ground fanks. The worm gears are of special gear bronze and are provided with a grey cast iron hub in the case of larger diameters. All standard drives available from stock are of the right-hand type. As regards their load bearing capacity, Atlanta worm-gear drive units are classifed according to centre distances. The maximum loading values indicated in the table have been calculated for standard worm drives (without cooling fan) and adequate dip-feed lubrication using synthetic gear oil (poly- glycol basis).