Hoover Dam and other hydroelectric power plants use steel’s strength to generate electricity that is distributed across vast regions of the country. 

An MCDP Staff Report

(Click here to see the story as it appears in the Jan.Feb. issue of Metal Casting Design & Purchasing.)

Metal castings play a large role in hydroelectric power generation. Hoover Dam, built during the Great Depression, holds Lake Mead, the largest reservoir in the U.S. by volume. It provides water storage, recreation, flood control, and perhaps most importantly, power for the states of California, Nevada, Arizona and Native American nations.

Massive Steel Castings

Cast steel products used in hydroelectric power generation include the runner blades, gates, crowns and bands that are assembled into turbines, as well as complete runners poured as single castings.

Turbine housings, which look very similar to small electric power components, are cast on a massive scale for hydroelecric power applications. At the Hoover Dam Powerplant facility shown above, which is open to public tours, they are enclosed in a walkable structure.

Auxiliary equipment featuring cast steel includes a variety of hydroelectric turbine valves’ doors and housings. These connect or cut off the circulation and flow of water, change its direction, adjust pressure and help ensure normal operation.

While these components require high strength, a key requirement for distributing power is more permeable electrical steels. Cast steel used for connections in the power distribution grid as well as transformers helps ensure the electricity generated reliably feeds into the grid and is delivered across vast tracts of land.

Castings Help Automotive Traffic Bypass the Dam

On the Colorado River side of Hoover Dam, a concrete bypass bridge reaches across the gap. Schwager Davis Inc., San Jose, Calif., built the post tensioning system for the steel wires and rebar used in its construction.

By number, about 25% of the system’s components are castings, including ductile iron cast parts from Farrar Corp., Norwich, Kan. Ductile iron is created from metals including reclaimed steel and iron.  The cast anchor heads and bearing plates are 37 inches in diameter and weigh 47 and 40 lbs., respectively.

Farrar delivered the finished parts complete and provides records of the castings for the life of the project.  Schwager Davis assembled the final part pictured above onsite. The bypass bridge project was completed in 2010.