The motorcycle engine crankcase is common produced by die casting aluminum alloy

and gate slag easily occurs in the die casting aluminum alloy crankcase.The gate slag is classed into three kinds of types:shrinkage cavity

oil

chilled layer.The main reasons are attributed to a higher mold temperature

excessive lubricant and high impurities in molten aluminum alloy.Through decreasing mold temperature

shrinkage cavity can be eliminated effectively.Aiming at oil slag

some measures

such as adjusting punch lubricant volume

adding location and supplying ways

were taken into account.For eliminating chilled layer slag

some ways are effective including modifying shoting time

staying time and strictly controlling degassing in the liquid aluminum alloy.