AEC Extruder Saves Customer Money with Redesigned Heatsink

Improved design showcases the flexibility of the extrusion process while delivering optimal product requirements

When Kirlin Lighting decided to update their center-mount lighting units, it was clear that the heatsink needed a redesign. Almag Aluminum, an AEC member in Brampton, Ontario, Canada was given the challenge: develop the heatsink for the new array style LED lighting application and take some of the mass out of the part. The extruder rose to the challenge, and then some.

Due to the flexibility of the extrusion process to place metal only where needed and to build in useful features, the new heatsink design provided a number of benefits. The new design features a center hollow core, which reduced the weight significantly - 47% compared to the original part.

The original shape with a solid core added unnecessary weight, explained Rob Nelson, Territory Sales Manager for Almag. "We hollowed out the center, leaving behind a cross-pattern with constant wall thickness (matching the fins) that didn't compromise structural strength." The four hollows created by the newly designed center core increased the surface area by 4%, a critical specification in adding to the efficiency of any heat sink.

The new extruded profile also replaced previously solid sections for screws, which needed to be drilled, with built-in screw ports for self-tapping screws, saving fabrication steps and reducing assembly time.

Kirlin was able to create a prototype with the initial concept for their internal testing. After the successful initial testing phase, a die was ordered, followed by die runs and further tweaking to ensure legs and screwports were according to specifications.

The redesigned finished heatsink foreground right) is shown in contrast to the previous, less efficient shape. The extrusion die (background) shows how the metal is extruded through the die openings to form the extruded profile.

The part was optimized for ease of extrusion, as well. Typical challenges with LED heatsinks are high tongue ratios (width of fin vs. height), thin walls, and high thick to thin transition ratios (uneven wall thickness throughout the part). The new LED heat sink uses 6063 alloy, which is able to hold the high tongue ratios and tight tolerances, while also providing high thermal conductivity.

Almag worked together with their sales, engineering and plant teams, their die maker, and their customer to design an optimal profile. "The relationship between Almag and our toolmaker, Exco Canada, is integral in being able to offer a solution to the customer in a case like this," said Joe Jackman, Vice President, Sales & Marketing for Almag Aluminum, Inc. "There is often much back and forth between Almag, the die maker, and our customer to truly figure out what will meet our customer's needs. Almag is known for designing and extruding complex shapes, but this one really tested our capabilites."

The final overall product is much lighter, saving the customer shipping, handling, and installation costs. And, because the part is now locally sourced, Kirlin Lighting, which previously purchased in high quantity to secure a reasonable cost and
ensure there were no supply issues, was able to reduce their
inventory and cost significantly.

For the more details and the complete story, visit www.almag.com.

Home page photo © Almag Aluminum Inc.