For the past 34 years, Superband has been developing its technology, casting machinery and resources to be specifically tailored to the automotive chassis components market. With automotive manufacturers looking to reduce chassis weight, aluminum has been the material many are turning to. Aluminum replacement parts can achieve up to a 50 percent weight reduction over other conventional materials. The challenge has been to find an economical and dependable means of production in an industry where safety and reliability are critical. Counter Pressure Casting (Superband) is an innovative process that combines economy with highly reliable mass production technology to manufacture superior quality aluminum parts.
Application
Superband is ideal for products that require a high strength-to-stress ratio to ensure safety and reliability. A perfect application would be chassis parts where high mechanical properties and ductility are needed in a very stable repeatable process, such as:
● Front and rear steering knuckles/spindles
● Upper and lower control arms
● Subframes
● Front & Rear Crossmembers
● Structural brackets
● Yokes
● Shock towers
Superband is able to maintain the mechanical properties and ductility of the part, showing little variation even in mass production. This innovative technology, combined with its efficient and highly productive casting machinery, make it the best choice for aluminum chassis parts production. Major automobile manufacturers worldwide are taking advantage of Superband's tried and proven process.
Process
There are many problems to watch for in other conventional aluminum casting processes such as low pressure, vacuum pressure, sand and squeeze casting. There is the chance of turbulent metal flow, the introduction of gases during filling and solidification porosity which contribute to the weakening of the casting’s structural integrity. These problems are reduced and controlled by Superband to provide castings of superior strength and reliability.
Superband uses two separate pressure chambers. The process begins by equally pressurizing both the furnace and the mold chambers. The pressure in the furnace is increased while the pressure in the mold chamber is released. (The pressure differential is usually between 300 to 1,000 mbar.) This allows the melt to rise in the filling tube(s) with constant counter pressure on the melt’s surface. The filling process is non-turbulent and allows for better control and uniformity. The continuous counter pressure on the casting chamber also prevents the introduction of gases that normally occurs during filling in other processes.
Solidification is controlled by using air or water for directional cooling. At the beginning of casting solidification, increased pressure is applied in the furnace chamber to achieve maximum feeding to areas prone to shrinkage. This ensures dimensional repeatability and increases the casting’s metal density. The constant pressure suppresses gases that would normally cause defects in the casting. Up to 6 bar of pressure may be applied without any risks to safety by using the closed-chamber system. When the casting has cooled, the pressure is quickly released in both chambers and the process is repeated.
