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Examples of Cavitation Effect in Die Casting. G. L. Lockwitz Harley-Davidson Motor Co. Universal Die Casting in 1980’s. Zinc tool Wind Split molding – car hood Cast holding studs Specs H-13 130 ft/sec 46-48 Rc 400 degrees surface of steel Pour about 850 degrees. Universal Failure.
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Examples of Cavitation Effect in Die Casting • G. L. Lockwitz • Harley-Davidson Motor Co. North American Die Casting Association – 114th Metalcasting Congress CastExpo’10, March 20-23, 2010 Orlando, Florida USA
Universal Die Casting in 1980’s • Zinc tool • Wind Split molding – car hood • Cast holding studs • Specs • H-13 • 130 ft/sec • 46-48 Rc • 400 degrees surface of steel • Pour about 850 degrees North American Die Casting Association – 114th Metalcasting Congress CastExpo’10, March 20-23, 2010 Orlando, Florida USA
Universal Failure • Sampling ran 50 shots • Took out for die prep • Large pit in cover halfabout .020 dia and .050-.010 deep North American Die Casting Association – 114th Metalcasting Congress CastExpo’10, March 20-23, 2010 Orlando, Florida USA
Cavitation 50 shots Side view of casting sectionwith cast stud Gate Pit in this area Wind split molding North American Die Casting Association – 114th Metalcasting Congress CastExpo’10, March 20-23, 2010 Orlando, Florida USA
Stopped Cavitation Effect • Welded pit • Eyebrow added to gate in line with flow • Diverted metal which changed pressure drop • Ran 100,000+ with no further problem. • Effectively the eyebrow did not allow a local pressure drop in this area to fall below the vapor pressure of the zinc • Cavitation inception did not occur North American Die Casting Association – 114th Metalcasting Congress CastExpo’10, March 20-23, 2010 Orlando, Florida USA
Side view of casting sectionwith cast stud Diverter in gate Gate Wind split molding The fix – change flow pattern North American Die Casting Association – 114th Metalcasting Congress CastExpo’10, March 20-23, 2010 Orlando, Florida USA
H-D Rocker Cover • High Cosmetic requirement • Early die replacement (25K shots) • Cavitation effect on fillets and radii • Excellent die tracking by caster • Photos taken every 5,000 shots North American Die Casting Association – 114th Metalcasting Congress CastExpo’10, March 20-23, 2010 Orlando, Florida USA
Harley Rocker Cover #89 – 35,000 ShotsCasting Photos Gated on this side North American Die Casting Association – 114th Metalcasting Congress CastExpo’10, March 20-23, 2010 Orlando, Florida USA
#103 Rocker – 65,000 Shots North American Die Casting Association – 114th Metalcasting Congress CastExpo’10, March 20-23, 2010 Orlando, Florida USA
#104 Rocker – 61,600 Shots North American Die Casting Association – 114th Metalcasting Congress CastExpo’10, March 20-23, 2010 Orlando, Florida USA