As I recall, they do plan to run these in reduced air pressure tunnels. It’s not so much that the tech doesn’t work, it’s just a lot harder to implement and maintain.
The advantage of lowering air pressure is less wind resistance which is a factor. However if the tubes are longer the more likely they are to break and not able to be hold pressure. Also between stops, if the tunnel needs to be re pressurized which could logistically lose any advantage of time savings of pressurized tubes.
Maybe it can work if they build it very deep and it an express train that only goes between capital cities of each province or something like that.
I guess that means that you’ll have to have really precise parking and stopping, have pressure gates to connect to all of the entrances to the train and make sure to maintain each gate with more points of failure and depressurization. The logistics of parking properly (AI assistance would be nice). It could be faster to connect logistically, but definately more points of failure. Then again even if the pressure fails, the concequence is only wasted money. its still a functional mag lift train.
If I lived in a country where the government focused on the future like China does, I’d rather invest in biomedical research, sustainable agriculture, and researching the means to industrialize without harming the environment.
CASIC says the flatness of its test track is within an 0.3 mm (0.01 inch) tolerance, that the 6 m (20 ft) diameter vacuum tubes have a geometric size error less than 2 mm (0.1 in)
The tolerances for the tube itself in most parts is not the issue. The tolerances at the points most likely to leak are the real issue. I guess we’ll see.
I imagine it will have an air lock system. You wouldn’t pressurize/depressurize the whole track. Just small sections at the beginning and end of the ride. You would board, and then the train pulls forward to a section of track that seals off from both the station and the rest of the track. That section is vacuumed then doors to the vacuum sealed rail open. Train moves out.
Then when nearing the next station the reverse is done. Train pulls into a section that is then sealed and pressurized. Then pulls forward into the station where people get off/board.
Assuming they would vacuum and pressurize the whole rail is silly. That’s like if they decided to depressurize the whole space station every time someone had to do a space walk. That’s not how that happens. The train would take up most of the space in the air lock section so there wouldn’t be nearly as much air to remove. It would probably take less time that you would spend boarding a commercial flight.
Yeah, it seems that it would only make sense for very long trips. I imagine you could just use pumps to ensure that there is low pressure even if there is some leakage in the tunnel. Making it underground tunnel would likely help with that as well. It might be more practical for shipping goods than people as well. You could just have this running say between a factory and a port, load up a bunch of goods, drop them off, and go back to pick up more. You could repressurize after the tug leaves too.
I hate how some people/reporters conflate maglev (with a technology that can work) with hyperloop/vacuum trains (which is a technology that doesn’t).
Same. Don’t sully the beautiful and working maglev trains with that garbage scam that killed any HSR hopes for millions of Californians.
As I recall, they do plan to run these in reduced air pressure tunnels. It’s not so much that the tech doesn’t work, it’s just a lot harder to implement and maintain.
The advantage of lowering air pressure is less wind resistance which is a factor. However if the tubes are longer the more likely they are to break and not able to be hold pressure. Also between stops, if the tunnel needs to be re pressurized which could logistically lose any advantage of time savings of pressurized tubes.
Maybe it can work if they build it very deep and it an express train that only goes between capital cities of each province or something like that.
You don’t have to re-pressurize the whole tunnel, just make a seal around the train doors.
Or an air lock system where the train pulls into it first then is re/de-pressurized depending on if it’s going into a station or leaving.
I guess that means that you’ll have to have really precise parking and stopping, have pressure gates to connect to all of the entrances to the train and make sure to maintain each gate with more points of failure and depressurization. The logistics of parking properly (AI assistance would be nice). It could be faster to connect logistically, but definately more points of failure. Then again even if the pressure fails, the concequence is only wasted money. its still a functional mag lift train.
If I lived in a country where the government focused on the future like China does, I’d rather invest in biomedical research, sustainable agriculture, and researching the means to industrialize without harming the environment.
The tolerances for the tube itself in most parts is not the issue. The tolerances at the points most likely to leak are the real issue. I guess we’ll see.
I imagine it will have an air lock system. You wouldn’t pressurize/depressurize the whole track. Just small sections at the beginning and end of the ride. You would board, and then the train pulls forward to a section of track that seals off from both the station and the rest of the track. That section is vacuumed then doors to the vacuum sealed rail open. Train moves out.
Then when nearing the next station the reverse is done. Train pulls into a section that is then sealed and pressurized. Then pulls forward into the station where people get off/board.
Assuming they would vacuum and pressurize the whole rail is silly. That’s like if they decided to depressurize the whole space station every time someone had to do a space walk. That’s not how that happens. The train would take up most of the space in the air lock section so there wouldn’t be nearly as much air to remove. It would probably take less time that you would spend boarding a commercial flight.
Yeah, it seems that it would only make sense for very long trips. I imagine you could just use pumps to ensure that there is low pressure even if there is some leakage in the tunnel. Making it underground tunnel would likely help with that as well. It might be more practical for shipping goods than people as well. You could just have this running say between a factory and a port, load up a bunch of goods, drop them off, and go back to pick up more. You could repressurize after the tug leaves too.
They are straight up pursuing a vacuum train
They announced it seven years ago with the eventual goal reaching 4,000 kilometres per hour by 2035 from memory
https://www.scmp.com/news/china/society/article/2109035/china-firms-plan-develop-4000-km/h-train-just-pipe-dream