Casting defect classification.pdf

Casting Defect Definitions PDF created with pdfFactory trial version 2Why classify defects ?Common communications ?So the real root cause can be developed based on history ?Utilization of common industry terms PDF created with pdfFactory trial version 3Regular Gas Blow ? Smooth, very round, bowl shaped ? Bottom can be seen with the eye ? Size and depth are easy to determine ? Usually a singular defect PDF created with pdfFactory trial version 4Irregular Gas Blow ? Bottom can be seen with the eye ? Depth is easy to determine ? Typically, multiple defects within a small area PDF created with pdfFactory trial version 5Pin Hole ? Smooth, very round, ‘black’ hole ? Bottom of can NOT be seen with the eye ? Size and depth are easy to determine PDF created with pdfFactory trial version 6Inclusion - Slag ? Irregular shaped ? Approximate 50/50 ratio of porosity and clean machined surface ? Defect area is usually larger than 5x5mm and can be as large as 10x10mm ? Needs to be analyzed by a trained metallurgist PDF created with pdfFactory trial version 7Sand Inclusion ? Irregular shaped ? Jagged edges ? Loose material can be easily removed ? Exact size and depth difficult to determine PDF created with pdfFactory trial version 8Handling damage ? Occurs after the casting has reached the solid state ? Usually accompanied by physical markings PDF created with pdfFactory trial version 9Hot tears ? Occurs when a tear or crack occurs before the metal has reached a solidified state ? Includes an oxide film in the tear region ? Often in areas of section- size transition ? Needs to be analyzed by a trained metallurgist Crank bore Liner boreLiner catcher Hot tear (with magnaglow) PDF created with pdfFactory trial version 10 Salt Pepper Porosity ? Widely dispersed, very small porosity visible on machined surfaces ? Common in aluminum alloys (hydrogen gas porosity) ? Typically not interconnected (will not form a leak path) PDF created with pdf