Casting Study: Hammer Cap

Operating at pressures ranging from 50 to 125 psi, the Danair Aerosmith hammer delivers up to 1,000 hammer blows per minute. During the early production phase finish machining exposed casting porosity and the cast iron air grille vents frequently broke during service. With a switch to ZA-12 alloy, the manufacturer created a part with tensile strength greater than iron and free of porosity. Moreover, the zinc alloy produces a smoother casting with a better feel. Machining was reduced and tool wear lowered. The ZA-12 alloy cap results in lower costs and greater reliability in the field. The alloy’s weight and density reduces fatigue by dampening the hammer recoil, eliminating damage to work surfaces and minimising worker fatigue.