Span. The span of a bridge crane refers to the distance between the center lines of the wheels at both ends of the main beam of the crane, that is, the distance between the center lines of the cart tracks, in meters (m). Overhead crane spans can be 10.5m, 13.5m, 16.5m, 19.5m, 22.5m, 25.5m, 28.5m, 31.5m and many others. Lifting height.