Mercedes-Benz M 450h Steel Fuel Tank Case Study

A luxury SUV hybrid vehicle, the 2010 Mercedes-Benz M 450h comes equipped with a 25 gallon sealed, steel fuel tank system that requires structural resistance to high internal pressure. Steel fuel tanks have an edge over conventional plastic tanks, as plastic tanks cannot meet the high internal operating pressures. The tank – produced by Magna Steyr in Austria – weighs 30.7 kg (67.5 pounds), including accessories, and is made up of 1.5 mm / 0.059 inch thick austenitic stainless steel. Plasma welding is used on the small flange of the saddle-shaped tank.

The Strategic Alliance for Steel Fuel Tanks and the United States Advanced Materials Program have conducted collaborative studies to analyze the use of steel in fuel tanks. These studies have shown that thinner stainless steel and structural enhancing techniques can be used to reduce the tank mass by 38 percent without increases in cost. As vehicle weight and emission requirements grow, steel fuel tanks continue to gain popularity.

About the Strategic Alliance for Steel Tanks (SASFT)
The Strategic Alliance for Fuel Tanks (SASFT) is an international alliance of companies specializing in the various areas of fuel tank production, possessing a common interest in the development, optimization and application of steel fuel tanks for automobiles. SASFT was organized by the American Iron and Steel Institute in 2000 to bring together the diverse business disciplines involved in designing, manufacturing and supplying steel fuel tanks in the automotive market. For more information on SASFT, please visit