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This is an Unimog pulling some kind of new british EMU. That's cool in itself. BUT LOOK AT THE WAY THEY PAINTED THE AIR TANKS. I love it because they store pressure energy  
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Jun 10, 2021 18:47
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So, err, today i learned about South Africa's coal trains. They work on 50 kilovolts. They can be 340 cars long, with 10 locomotives. With a total mass of 41.000 tonnes. I've never heard about it until now, and i've always been kinda interested in trains. Is the existence of this bizarrely huge train common knowledge and am i living under a rock? https://en.wikipedia.org/wiki/Sishen%E2%80%93Saldanha_railway_line
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Jul 3, 2021 21:24
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For a while, the Netherlands held the record of the longest *passenger* train in the world. A single bog standard 1600 locomotive was used (1,5kV, 4600kw, DC traction motors with thyristor choppers), with type ICR carriages. (length over buffers 26,4m) It is a really weird sight to see such a long passenger train. Even freight trains aren't usually this long. https://www.youtube.com/watch?v=eeVN9nSxwDs There were significant problems in getting this to work. Not relating to the tractive effort - the locomotive could handle it just fine. Braking, however, was a whole different story. Firstly, filling the whole train brake pipe took ages. But worse, at first they didn't manage to get the brake command to travel further downtrain than about 400m or 17 carriages... They don't usually pull more than 12 carriages. Neither the carriages nor the locomotive was designed to be able to brake such long trains. They didn't find a way to solve that problem. However, they did manage to find a way to make the carriages go in emergency brake mode, with a very specific process: - The electronic-pneumatic brake controller had to be in its hardest brake setting - the emergency brake button had to be pushed - An auxillary, manual emergency brake valve had to be fully opened. This made the brake pipe empty with incredible speed, so the pressure wave would ripple through the whole train. This was a viable way to get the train stopped in case of emergency. In the test, the pressure shock waves bouncing through the continuous air line were big enough to make some brakes actually start to brake again, for a very short while as the shock wave passed. They had to pull a lot of strings to make sure the whole route of the train through the country, would be guaranteed to have green signals. This was quite a big thing, because the dutch main rail net is incredibly busy. Busy enough to occasionally create a traffic jam if things go wrong in rush hour. If you're dutch (or use google translate), here's a very nice and long report by a train driver about the whole event: http://www.feijenoordsemeesters.nl/LRtW/index.html LimaBiker fucked around with this message at 22:57 on Jul 7, 2021 |
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Jul 7, 2021 22:47
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Wtf, i swear i wrote down the length of the train. Oh well. 60 carriages, each 26,4m over buffers, and a locomotive. So heel erg lang. monsterzero posted:WTF Did it service three station simultaneously when it finally stopped? I looked to see if it was possible, but best i can do is service 3 stations with a single train movement! I don't think there's any place here that has 3 stations within 1600m. Amsterdam:  Purmerend:  Distance measurement is not totally accurate, i put it to the side of the rail line on the map to make it easier to see the route and stations. Edit: Ooh, we also once had the world's longest city tram, on 7 april 1990: https://www.youtube.com/watch?v=U32VJtg8J8k&t=617s Total mass 184 ton, length 158m. Not extremely long, but it looks quite silly in the narrow streets of Amsterdam. For some reason they chose to use only one tram to pull the whole thing. Not bad for a total power of about 200kw. In the end, they snapped a coupler and the tram couldn't continue to the destination as one piece. LimaBiker fucked around with this message at 20:52 on Jul 8, 2021 |
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Jul 8, 2021 18:57
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Jonny Nox posted:what was the point of having the longest passenger train ever? Yep. It was a '150 years of dutch rail' event. It wasn't very practical cause it couldn't brake 'regularly' (either full emergency, or nothing, no other options (except for the tiny bit of dynamic braking) and the locomotive's electric system could only supply power for the heaters of the first 17 carriages. They solved the brake problem by throwing off the schedules of all other trains, and give this train guaranteed green signals on the whole trip. Stopping the long train would mean having it sit for 15 or 30 minutes or whatever to get the brakes back up to pressure, and to occupy 2 or 3 blocks of track while it's sitting there, causing serious traffic jams on the rail. So it was never intended as a means of travel, just a 'hey, let's do something spectacular'. They had 900 people aboard of the first 17 carriages - the rest of them only had some staff in them to help with the technical side of things (like making sure the rat tailing/bumping on acceleration wasn't too violent, see if the brake command reaches the carriage etc)
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Jul 9, 2021 13:50
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https://www.youtube.com/watch?v=VkMMs_1UL5Y German/deutsche bahn safety movie about the 15kV overhead power line, from the time when steam locomotives were still very common. Includes various 'Oh no, but what's he doing! He knows he shouldn't do that *ZAP!*... Oh dear, if only he would've followed procedure' scenes. The automatically translated subtitles are doable, for those who don't speak german. The language is really nice and poetic though! "Fifteen thousand volts. No one can see them sitting inside the power line, but they're constantly at ready, to power heavy locomotives with their tremendous loads and make them move. They're not only ready to move the locomotives, though. They're also constantly willing to reach ground. Only two things prevent them from doing that. The insulators, and the great distance between the catenary and the ground'. Sigh, it doesn't really translate well... Oh well. Watch it. Learn german. Slight NMS warning for some photos of electric burns when the doctor scene happens, and he starts pulling them out. LimaBiker fucked around with this message at 19:31 on Jan 21, 2022 |
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Jan 21, 2022 18:05
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Sooo i just found out that in 2005 a bunch of train geeks arranged a vintage train trip through north korea. I didn't even know they did those. The steam locomotives look incredibly rickety. Here's an hour's worth of tram and train footage. https://www.youtube.com/watch?v=Xfb7ap7kXdY The maker of the sign probably has never seen a steam locomotive in his life: 
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Jan 22, 2022 18:46
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https://twitter.com/Metra/status/1485666351024951307 Epic track heaters. We have gas heaters on switch points here too, but without visible flames.
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Jan 25, 2022 20:45
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There are videos on youtube of a chinese coal mine in the mid 2010s where they still use steam engines. The last steam engine made in the Datong factory was made in 1988.
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Feb 1, 2022 08:01
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GotLag posted:What's the reason for the sudden change in sound 11 seconds in? The local diesel-electric commuter trains did that too and I could never work it out. There are power electronics converting DC, or rectified single phase AC into 3 phase AC with variable frequency. The sound you hear are the pulse width modulation systems, that turn the rectified voltage into 3 separate sine waves again. Why the frequency of the PWM changes, and not only the width of the pulses, that i don't know. I do know that you can program an ICE 3 EMU to buzz the german national anthem: https://www.youtube.com/watch?v=PV2E66JNKpU And that the Taurus locomotives are programmed in such a way that they play an actual musical scale, probably just for the sake of making a pleasant noise: https://www.youtube.com/watch?v=tNxh2bMWPOQ And those things make all kinds of weird sounds when there is wheel slip. Program them with a jazz scale and they could sound even funkier i reckon: https://www.youtube.com/watch?v=jZkOfJzkWXA&t=69s
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Apr 18, 2022 12:19
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Europe has a ton of different countries. It makes a big difference whether you're gonna be a train driver in Hungary or whether you're gonna do it in Germany. Or the Netherlands, where you can cross the country multiple times on a day and still end up at your home station that day.
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May 3, 2022 09:28
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I am very happy that firing a coal locomotive is not something i have to do day in day out for years on end
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Jun 16, 2022 18:03
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Itty bitty EMU comittee!
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Oct 30, 2022 10:13
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https://www.youtube.com/watch?v=8GujoYkaQf8 Some railway hired a locomotive and crew to shuttle around a couple thousand tons of ballast. Initially the work would be done with a diesel. The crew showed up with a steam locomotive. Turned into germans They pulled about 1000 tons with it. 20 flatcars with ballast. Sounds gooooood. The three cylinder steam loco has an interesting rhythm to it. LimaBiker fucked around with this message at 19:41 on Feb 19, 2023 |
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Feb 19, 2023 19:38
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There are quite a few hobbyists that own and operate a couple of old locomotives for preservation reasons - and making it somewhat break even by hauling non-passenger trains around. Apparently it's pretty doable in the Netherlands because even just little groups of a handful of people can do it.
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Mar 22, 2023 14:17
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Noosphere posted:That seems rather suboptimal from the passengers perspective. What if someone wants to go from DC to NY ? Having a half empty train do that trip that allows no one to board in DC sounds silly. An obvious solution would be to not allow booking in advance, but if you buy a ticket and get on, you can try finding a seat, or travel standing. The IC trains from Amsterdam to various german places charge separately for the train ticket and the seat reservation. You can travel on them along any stretch you want, but are only guaranteed a seat if you book the seat (which is 5 or 10 euro or so). You can, of course, sit in an already reserved place without a seat ticket. When the ticket holder arrives, you are expected to give up your seat. You can be lucky and have a seat for the entire 6:45 trip from Amsterdam to Berlin without having a seat reservation, but for such long rides it's of course way better to actually get the seat reservation. If you only use the IC to travel within the netherlands for like half an hour, you don't have to bother. Usually there's a seat free outside of rush hour, and otherwise you stand for such a short stretch.
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Mar 30, 2023 11:09
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Saukkis posted:What would it have required to prevent or reduce the destruction? From the information I've read the train passed inspection point right before the tunnel so the wheel broke inside. Would microphones or other vibration sensors attached to the rails at regular intervals worked? Or other microphones in the tunnel. Seems that most other detection equipment could only do spot checks and might leave too big gaps. If the wheel was cracked, perhaps a wheel tapper (the guy who hits every wheel of the train with a long hammer) could've found it. Wheel tappers are rare in western europe, but you still find them on certain east european stations.
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Sep 4, 2023 20:48
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Saukkis posted:I'm not concerned with speculation, we can just take the current information as valid and assume the wheel failed suddenly. Even if it turns out to be incorrect and it could have been detected prefailure can we trust that a wheel or some other component can't failure until the train is well past the tunnel if has passed an inspection. https://www.youtube.com/watch?v=ycPEBwDm0GI https://www.youtube.com/watch?v=RijZjxEf6PQ It looks a bit silly but the ring of an intact VS a cracked wheel is apparently different enough to make a totally different sound. You could also install a massively expensive radiography machine on the track feeding the tunnel and have it X-ray all the wheels, but that's not practical, in the way that proper shielding is hard with the intense radiation needed to look through thick train wheels, and when it needs to be 'open' enough to let a whole train run through it. Detecting an already broken wheel or derailed wagon is a wholly different story. Wheel load sensors on each rail could detect wheel that should be there but isn't (in other words a missing wheel or disintegrated rim on duoblock wheels), or a heavily asymmetric load of the axle. Vibration sensors could definitely pick up on heavy wagons dragging over the ground. They could then alert a supervisor who can verify by camera if there really is something bad going on.
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Sep 5, 2023 08:35
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wilfredmerriweathr posted:Who the gently caress did a copyright takedown claim on a loving train video? The notice says "fiona thomson", that's who.
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Nov 2, 2023 17:32
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No clue. Just fiona thomson, without capitalisation.
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Nov 4, 2023 10:36
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| # ¿ May 12, 2024 16:25 |
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Often phenolic resin binders are used in brake pads.
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Feb 29, 2024 13:35
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