Railroad thermite welding
Why Hacker News recommends it
Cited as a concrete example of how thermite is used for track welding in discussions of rail and thermite.
What it is
A short video of railroad workers in Storfors, Sweden, using thermite to weld rail sections together.
Recommended by 0 HN commenters across 0 different months, 2017 to 2024.
What Hacker News said
Cites Laforet · 2017-09 · on “Anatomy of a Moral Panic”
I might be wrong about this, but I think thermite is used more often as a simple welding method. Railroad workers doing track maintainence routinely use thermite to repair damaged sections. [this video]
Cites jpollock · 2022-07 · on “Why rails buckle in Britain”
This drove me down a rabbit hole, so I thought I would share. Track used to be separate pieces (seemingly before 1950), but they are now continuous welded rail [1][3]. This was done to allow trains to go faster, and lowers maintenance on the trains. This confused me because trains go "clack clack clack" - I guess that's foley now. However, it means track is more prone to buckling, since there aren't any expansion joints, like we have on bridges. Slack is added/removed from the rails by stressing the track during installation [2]. They heat (or mechanically stretch) the track to the length at a chosen "neutral" temperature. Then they install the track. This allows them to calculate the max ex
Cites philip1209 · 2024-02 · on “Check Out These Self-Soldering Sleeves from World War II”
Depends. It's used for welding, and the output is iron (magnetic): [this video] I assume it would be too difficult to trigger the thermite reaction in the field with WWII tech, among other problems.