When Donald Engineering sales manager Jim Kortman describes his aluminum extruder client of 28 years, he reaches for a deceptively simple analogy: the Play-Doh Fun Factory. An aluminum billet goes into an extruder, the aluminum is heated, a plunger squeezes the material, and formed aluminum emerges in whatever “profile” shape the die forms.
To reduce overall weight in final assemblies, aluminum structural components are often used instead of steel. The applications of these components can be life-or-death serious, which is why they require the most rigorous and precise crush analysis. Donald Engineering’s client began with making precision-machined aluminum parts for the office equipment market, then moved into automotive parts, including sunroof tracks and structural components. The construction of such bent tracks is more nuanced than it might appear. Kortman likens it to bending a stick over one’s knee, wherein the outer side stretches to the point of snapping (tension) while the inner side crumples and deforms (compression). Achieving such bends with heated material is easier, but it sacrifices dimensional stability. Thus, the client works with cold (room temperature) extrusion.