New product announcements: 02/11/2009 Crawler Excavator: Redesigned for Better Fuel Efficiency The DX350 crawler excavator is powered by a 270-hp, 1,900-rpm Doosan Tier III engine and features an electronic optimized hydraulic system for improved fuel efficiency. The excavator has an arm digging force of 39,460 lb and a bucket digging force of 54,010 lb. Polymer shims and a redesigned boom, arm and bucket allow for greasing intervals of 250 hours. The cab features a transparent roof for greater visibility. The excavator’s dual-walled muffler reduces operational noise levels. Doosan Infracore America; 770-831-2200; www.infracore.com Remotely Operated Dowel-Pin Drill: Get a Better View The
Arch dams, classically curved monoliths situated in narrow valleys, are not as common as other types of dams, such as embankment dams and gravity dams. ENR takes a look at some of the biggest arch dams in the world, both completed and under construction.