Why Railroads Don't Need Expansion Joints
5.3M views · Dec 5, 2023 · Education
Comments · 3.3K
@PracticalEngineeringChannel · 2 years ago (edited) · pinned
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@xavierburval4128 · 2 years ago
I love that the primary solution for buckling is just “do it on a really hot day lol.” It’s the kind of thing that sounds way too dumb to work but is somehow the most genius solution ever.
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@gregyjoebatin2558 · 2 years ago
As a civil engineer, this type of content is therapy
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@TheRealFumigator · 2 years ago
My 14 yo son was telling me about metal expansion he'd learned about in school and we got onto the topic of railroads. I mentioned they don't really put railroad down in sections anymore and he asked how they accounted for expansion. I realized-- I had no idea! So thank you for this great video-- I now know.
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@petepi · 2 years ago
"Stress is what breaks things" is a truth that more people should apply to their own lives
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@pschlik · 2 years ago
Fun fact: The problem with 'rock n' roll' (more formally, harmonic rocking) is bad enough that rulebooks disallow travelling at certain speeds on jointed rail. The rulebook I have says this danger zone is 13 to 21 mph, so if your train only has enough power to reach 20 mph (entirely possible, if normal, these days) safety says you'd have to slow to 13 mph on jointed rail. So CWR not only makes maintenance-of-way's job easier, it also makes operating the trains a bit easier and safer too.
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@JohnWick-cz1ti · 2 years ago
As a medium carbon steel rod I find this content traumatic.
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@mvcrailphotos · 2 years ago (edited)
As a engineer who works in railway track design, one thing I'd like to point out - especially since you mentioned a video on signaling will be coming soon - is that neutral temperature is typically high not because a broken rail is less dangerous than a sun kink. Yes, its more likely that a train could operate over a pull-apart rather than theough a sun kink, but largely because the signal system will detect a pull-apart as a discontinuity in the rails and thus the signal circuit - automatically turning the signal ahead of that track to red!
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@MikeV8652 · 2 years ago
If anyone wonders why the odd figure of 39 feet was the standard length of single sticks of traditional jointed rail, it was so that they'd fit into 40-foot gondola cars. Welded rail is now typically manufactured in long lengths (1,320 feet in the USA, which is ¼ mile) and can be welded in the field to be continuous. Such long rails are transported on special rail trains, like the one Grady shows half-loaded at <a href="https://www.youtube.com/watch?v=zqmOSMAtadc&t=25">0:25</a>. The yellow racks hold them in place, and the rails bend as the train goes through horizontal and vertical curves 😮.
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@yacht-responce · 2 years ago
<a href="https://www.youtube.com/watch?v=zqmOSMAtadc&t=158">2:38</a> As a Korean i'd say chikchikpokpok(칙칙폭폭) is onomatopoeia of a steam locomotive, which in English chug-chug. Korean language really don't have word for railway sound. I mean we can, but it's not devoted for that sound. Japanese word "Gatan-goton(ガタンゴトン)" describes exact same sound of clickety-clack.
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@Sam-bn9ix · 2 years ago
Railway engineer here! A few points:<br>Not all rail is made of the same alloys, particularly high load areas such as points and crossings. These use harder metals to reduce wear, such as manganese. Adding this into the equation means welding plain line to p&c is a particularly complex job.<br>I am also glad you mentioned track circuit will be covered later on as that is a big downside to CWR with older signalling systems. <br>Aluminothermic welding is spectacular when it goes wrong, search it up!
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@Yikes5824 · 2 years ago
This is the first question I ever asked on the “internet” - a Compuserve message forum - back in 1989, and it was answered by a Canadian rail worker. That’s when I knew we were in a new era.
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