Products 08/04/2010 Flap-Disc Abrasives: Redesigned for Higher Performance DeWalt’s Extended-Performance Flap Discs are designed with a more durable cloth that has an improved grain and resin compared to previous DeWalt high-performance flap discs. The discs have been redesigned with a significantly larger surface area as well as a longer usage life. DeWalt now is offering Wearable Flap Discs for weld blending, material removal and welding preparation. The discs feature a backing that wears away as the disc is used, which allows for full access to the cloth. The removal rate is comparable to conventional grinding wheels. DeWalt; 800-433-9258; www.dewalt.com Extra
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.