Ejector pins are long pins that are used in the injection molding industry to push the final molded product out of the mold. They are used forcefully to eject the solid part out of the plastic injection mold and are usually made of high-quality steel. They are also known as knockout pins, knock-out pins or KO pins.
Typically, these pins are extended and retracted to force the part out of the molded cavity and are the cheapest means of ejection. The pins might leave marks behind, so they are usually applied only when the parts have sufficiently cooled down, to avoid the deforming the parts. Ejector pins of injection mould are available in various sizes and shapes, such as round, bevel-headed, straight and cylindrical. They can be customized and precision-engineered to suit the application. Important factors for one to consider when selecting pins are corrosion resistance, durability, tolerance and tensile strength.
It’s important for the right type of mould ejector pins to be selected for efficient part production in plastic injection molding applications. There are three different types of ejector pins available. Each type possesses specific characteristics, and they are used in different environments. The most important factor that differentiates these pins is the temperature at which they can be used, because this affects their durability and life span. Pins made for low temperature environments will deteriorate rapidly when used in a high-temperature setting.