Abstract: A Moldflow software was used to analyze the injection molding conditions for auto front bumper production and also to simulate the injection gate distribution for the injection mold. The balance injection molding process was realized by use of the needle valve hot runner sequential injectionmolding technology. A threestep ejection for inner lateral structure was adopted to achieve automatic ejection with the high production efficiency and quality for the auto front bumper.

Key words: bumper, injection molding, sequential injection, hot runner, simulation