Why They Freeze This Metal Before Installing It

追加: 2026-06-03

[00:00:00]This metal pin is literally frozen to -80° just so it can fit into a hole that's technically too small. Engineers call this an interference fit, where the pin is made slightly oversized so it locks in with zero movement. But there's a catch. The second the metal starts warming up, it expands and can get stuck before it's all the way in. That's why everything has to be perfectly lined up and done fast. And if freezing the pin isn't enough, they heat the outer part to make the hole expand. One part cold, one part hot. And the pin slides right in. Then, once everything reaches room temperature, it's locked in place for good.