Casting Study: Double-Diaphragm Pump – Warren Rupp

For this design, a series of machined stainless steel air valve spacers were replaced with zinc die castings. Because of the spacer’s large flow areas, engineered plastics do not have the required strength to maintain shape and rigidity. Die cast ZA-8 was chosen for high mechanical properties and net shape production. In addition to cost reduction, die casting maximized air flow by allowing the spacer to be designed for fit and function without machining restrictions. Three spacer sizes are used for five pump models.