Casting Study: Frame Housing and Five Additional Mechanical Components

Key material requirements for the office bundling machine are hardness and strength, the ability to hold good tolerances, and lubricity. ZA-27 was selected as the die casting material because of its hardness, strength, dimensional stability, and natural lubricity. By designing the frame housing as a die casting, 27 separate parts were combined into a single casting. Receptacles for pressed-in bearings for ground-and-polished shafts needed only slight finish-reaming before bearing insertion. The bundling mechanism incorporates both rotary and sliding motion. While some motions are intended to be lubricated through oil ports, the inherent lubricity of ZA-27 provides a margin of protection against user neglect, adequate by itself to support a particular motion, or both. Using ZA-27 also decreased weight, permitting the unit to be handled and shipped easily.