Ejector Pins & Sleeves
Berger Tools stock a large range of ejector pins and sleeves, including double sleeved, cylindrical head, and countersunk variants.
Ejector pins are used to eject completed parts from die moulds and are commonly used in the plastics, automotive, aeromotive and medical industries, amongst others. A blade shape is used when there is only a small surface area on the finished part. They are also known as knockout pins, knock-out pins or KO pins. When the mould is opened, the pins extend into the mould cavity, push the part out, and then retract, allowing the mould to close and be refilled.
Important factors to consider when selecting ejector pins are corrosion resistance, durability, tolerance and tensile strength. Ejector pins can be made with a variety of treatments, which affect the hardness of the pin. By choosing the right ejector pin for the application, the lifespan and durability of the pin will be enhanced.
Through hardened pins are good all-purpose steel pins that are heat-treated to be uniformly hard throughout their diameter. They are often used for injection moulding of plastics and can be used in cooler moulding environments below 200°C.
Case hardened pins are nitrided pins that are suitable for die casting and can be drilled or tapped. They can be used at temperatures above 200°C and are quite durable. They can chip when compared to through hardened pins but have a greater life expectancy at higher temperatures.
Blackened or oxidated ejector pins are designed for extremely high temperature working environments. They can be used at temperatures from about 600-1000°C. These ejector pins have a self lubricating surface coating that allows them to be used at these high temperatures.
Ejector pins can be further enhanced by our DLC coating and other coatings which protect them and make them more durable. These coatings work by reducing friction so that the pins become more wear resistant and the ejection of the part becomes more consistent.
Ejector sleeves are hollow and can be used to protect and guide the pin, further enhancing its lifespan.