Flexible Metal's EV Drop Tube Design Leads to Trusted Partnership

When product engineers working on a battery coolant line for an EV auto maker designed themselves into a corner, they reached out for a lifeline.

An EV auto maker faced several challenges. It needed a flexible way to connect drop tubes to the battery coolant line; manage pressure, vibration and fluctuating temperatures; and withstand a range of operating conditions, including a potential catastrophic thermal runaway event.

On the receiving end was Flexible Metal, a bellows and tubular systems manufacturer with decades of experience supporting industry giants like GM, Ford, John Deere and other OEMs facing design and manufacturing challenges.

Development and Manufacturing

Supporting a specific design profile and geometry requirements and incorporating extremely tight tolerances meant creating a unique design and manufacturing process. Flexible Metal designed a thin-wall drop tube with flexible metal bellows - one set of rigid convolutions to create a bend in the thin material and another set of more flexible convolutions to satisfy movement specifications.

Due to the specialized manufacturing requirements of the metal drop tubes, Flexible Metal built the machinery needed to support the program, including 13 custom-built small-diameter hydroformers. It also developed a trimming process to trim the thin-walled tube without damaging the shape, and included a lead-in chamfer to mate with the other components.

Read more in the latest Automotive Powertrain Technology publication.