E FIXED CONSTRUCTIONS
E02 HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
E02F DREDGING; SOIL-SHIFTING
E02F3/00 Dredgers; Soil-shifting machines
E02F3/04 mechanically-driven
E02F3/28 with digging tools mounted on a dipper- or bucket-arm; , i.e. there is either one arm or a pair of arms; , e.g. dippers, buckets