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Elasto Proxy's Sealing Solutions Blog

Elasto Proxy's Sealing Solutions Blog is the place for conversation and discussion about the design and custom fabrication of rubber and plastic components. For nearly 25 years, our family-owned company has provided high-quality, low-volume seals to a variety of industries. Doug Sharpe, Elasto Proxy's co-founder, is a former president of the International Sealing Distribution Association (ISD), a not-for-profit trade association that enhances member success through information, education, and interaction. By blogging for CR4 in this same supportive and collaborative spirit, Doug and other members of the Elasto Proxy team will share our experiences with you.

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31 comments

Would You Travel by Vacuum-Tube Train?

Posted September 02, 2014 4:14 PM by Doug Sharpe

Thomas Edison discovered that electricity could travel in a vacuum. Elon Musk, the founder of Tesla Motors, may yet prove that vacuum tubes can transport rail passengers, too. Although the Canadian-American billionaire ruled out the use of vacuum tunnels in his proposed Hyperloop transportation system, a company called Terraspan is now curiously quiet about building a 4,000 mph (6,437 km/h) vacuum tube train, which would double as a superconducting power line.

Back in the summer of 2012, the website Gizmag asked readers why such an ultra-efficient, high-speed train wasn't being built. Did Terraspan determine that vacuum-tube transport was unsafe? Was the cost of using mag-lev technology too high? Pay a visit to the Terraspan website today, and you're prompted to "stay posted for the latest on how Terraspan and Hyperloop complement each other." So what might Terraspan have in mind, and do vacuum tubes have a place in our transportation future?

The Past as Prologue

During the 1800s, pneumatic tubes transported telegrams and inspired inventors to envision projects for moving people. New York City's first subway system, the Beach Pneumatic Transit, could fit 22 travelers in a single car, but lasted just three years. Terrapsan's plans are far more ambitious than a 312-ft. train tunnel and a massive fan. According to the Gizmag article, the futuristic transit company aims to build a network of underground vacuum tunnels that would link eastern Canada to points south and west.

That's not all either. "Embedded in the train tunnel network," the article continues, "would be a series of thick superconducting energy cables that would form the heart of the first true continental power grid." Does that remind you of Are Solar Roads the Way of the Future?, Elasto Proxy's controversial blog entry about the viability of solar paneled roadways and their underground conduits for power cables? As a noted non-engineer named William Shakespeare once wrote, "What's past is prologue."

It Will (Never) Work

Are vacuum-tube trains viable? That's not an idle question for business travelers like me. As the co-founder and co-owner of a global company with headquarters in Quebec, I could travel from Montreal to Shanghai in just under two hours, and from Montreal to Sao Paulo in even less time than that. Mag-lev technology isn't new, but are Terraspan's plans cost-effective? Building Japan's Linimo HSST, a low-speed mag-lev line, cost approximately $100-million (USD) per 0.62 miles.

Concerns about cost are just scratching the surface, too. For example, how well would Elon Musk's Hyperloop, which has been likened to "a cross between Concorde, a railgun, and an air hockey table", work in the real world? In the Terraspan system, how well would the vacuum function if part of a tube wall failed? In other words, would efficiency losses mean that the trains no longer run on-time?

What We Know

Recently, Elon Musk posted a 57-page proof-of-concept about the Hyperloop Alpha. According to the abstract, Hyperloop would feature low-pressure capsules that are "supported on a cushion of air" and "accelerated via a magnetic linear accelerator affixed at various stations on the low pressure tube with rotors contained in each capsule." For travelers like you and me, the cost of a one-way ticket from Los Angeles to San Francisco would be an estimated $20 (USD).

Hyperloop Alpha won't help with my own intercontinental travel plans, but both Musk's capsules and Terraspan's trains would surely need the kind of sealing and insulation solutions that Elasto Proxy can provide. Wind, rain, and sunlight aren't part of a vacuum tube's environment, of course, but railcar designers must still account for a variety of factors in compound selection and part design. Ultimately, both vehicle performance and passenger safety are critical in all transportation applications.

What We Wonder About

Here at Elasto Proxy, we're following mass transit innovations with great interest. At the same time, concepts such as the Hyperloop Alpha and Terraspan raise many questions. For example, would the demand for lightweight rubber materials be more, less, or about the same with ultra-efficient trains? In terms of passenger health and safety, how would flame, smoke, and toxicity (FST) standards evolve, and what could that mean for the use of fireproof rubber materials?

Underground vacuum-tube trains would need other critical components, too. As Elon Musk's proof-of-concept explains, "a ground based high speed rail system is susceptible to Earthquakes and needs frequent expansion joints to deal with thermal expansion/contraction and subtle, large scale land movement." As a supplier to the building and construction industry, Elasto Proxy has met custom fabrication challenges like this, too.

Is the Hyperloop Alpha a bridge too far? Will Terraspan build a network of high-speed international trains? Will Elon Musk and others take the giant strides of Thomas Edison, or will they follow in the small footsteps of Alfred Beach, inventor of New York's short-lived pneumatic subway?

About the Author: Doug Sharpe is the President of Elasto Proxy, Inc. (Boisbriand, Quebec, Canada), supplier of sealing solutions and custom-fabricated rubber and plastic parts to a variety of industries, including green power, mass transit, and building and construction.

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#1

Re: Would You Travel by Vacuum-Tube Train?

09/02/2014 9:32 PM

Is that an old Soviet era train designed to withstand EMP pulses? ;-)

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#2

Re: Would You Travel by Vacuum-Tube Train?

09/02/2014 9:46 PM

The concept has been around for a while.

http://www.popsci.com/scitech/article/2004-04/trans-atlantic-maglev

The preliminary plans were a bit on the expensive side, the technology also isn't really there yet either.

In the future, who knows?

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#3

Re: Would You Travel by Vacuum-Tube Train?

09/02/2014 10:32 PM

What a pile of vacuous drivel.

When Thomas Edison entered Cooper Union college, William Crookes and others had already developed the Crookes tube that demonstrated how an electron can travel in a vacuum. Now Edison did dabble in using these vacuum tubes in and shortly after school but it was John Ambrose Fleming that invented the first tube diode. [He was a paid consultant for both Marconi and Edison.] Lee De Forest is accredited with inventing the triode vacuum tube that made amplification possible.

If the author of this article gets the very first sentence so blatantly wrong is there any reason to read anything else!

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#4

Re: Would You Travel by Vacuum-Tube Train?

09/03/2014 12:57 AM

"For travelers like you and me, the cost of a one-way ticket from Los Angeles to San Francisco would be an estimated $20 (USD)."

Not in a million years, unless Elon is willing to subsidize 90% of the ticket cost, or the passengers and freight are vacuum packed for transport.

The author is motivated by a desire to expand his company's market and that is fine.

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#5

Re: Would You Travel by Vacuum-Tube Train?

09/03/2014 1:16 AM

If vacuum tube is underground,in case of an accident or earthquake very serious damage will occur. If it is overhead it would be more safer to attend.

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#6

Re: Would You Travel by Vacuum-Tube Train?

09/03/2014 2:25 AM

Decimal points are just like darts; you can throw them anywhere.

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#7

Re: Would You Travel by Vacuum-Tube Train?

09/03/2014 6:13 AM

Nice Blog entry, well laid out with a lot of links. But what is wrong with this statement? "Thomas Edison discovered that electricity could travel in a vacuum."

Yea, maybe others discovered it before him and perhaps some after. It always did travel in a vacuum. He did not make it happen, he just happened to learn about it, good for him. I am pretty sure he went on to do some pretty cool things with it when that light bulb went on in his head, LOL!

and the cost may be 20 bucks for a nice ride but we will pay a ton more just because we are willing to do it and of course our governments large and small have to suck money from somewhere all the time or else they run out of it.

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#8
In reply to #7

Re: Would You Travel by Vacuum-Tube Train?

09/03/2014 7:05 AM

It always did travel in a vacuum. He did not make it happen, he just happened to learn about it

I don't think anyone has claimed that Edison 'made it happen'. The word chosen was 'discovered'. Why belittle that achievement?

Numerous physical properties and relationships as well as geographical features have been discovered and credit is given to those who do (not always correctly as there is sometimes politics involved).

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In reply to #7

Re: Would You Travel by Vacuum-Tube Train?

09/03/2014 7:06 AM

It always did travel in a vacuum. He did not make it happen, he just happened to learn about it

I don't think anyone has claimed that Edison 'made it happen'. The word chosen was 'discovered'. Why belittle that achievement?

Numerous physical properties and relationships as well as geographical features have been discovered and credit is given to those who do (not always correctly as there is sometimes politics involved).

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#10

Re: Would You Travel by Vacuum-Tube Train?

09/03/2014 7:17 AM

I heard you the first time, LOL. I don't belittle the term 'discovered'. I guess the question is can someone discover something that has already been discovered by others?

Regardless, my point is that although the first line may be semantically incorrect, that should not make the rest of the post fodder for the dust bin in and of itself.

I just discovered it is possible to accidentally double post a comment. Or was that on purpose?

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Re: Would You Travel by Vacuum-Tube Train?

09/03/2014 7:44 AM

Sorry, my double comment was unintentional. I selected the submit comment button and got an error message, so I backed up, copied and resubmitted (highlighting a quote from your comment).

If your intent was to point out that Edison being credited with discovering something that had already been discovered, that's been pointed out and it happens from time to time. Your previous comment seemed more to criticize discovery versus creation. Or maybe I just read too much into it.

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Re: Would You Travel by Vacuum-Tube Train?

09/03/2014 8:21 AM

Would You Travel by Vacuum-Tube Train?

No.

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#13

Re: Would You Travel by Vacuum-Tube Train?

09/03/2014 8:46 AM

It was a misunderstanding, I was referring to comment #3 about who discovered what when.

As far as the original question goes though, I would travel by Vacuum-tube train after I was satisfied that the train stays in the vacuum and the vacuum stays out of the train.

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#14
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Re: Would You Travel by Vacuum-Tube Train?

09/03/2014 9:35 AM

Sigh, you misunderstand my point.

When the opening sentence of an article presented to an engineering forum contains a glaring historical engineering inaccuracy the rest of the article is likely to be a puff piece. Confirmation of fluff can be found in the artistic image leading the article. An aerodynamic train design in a vacuum tunnel looks bogus to me. Add the the meaningless, eye catching buzz words of "Energy Efficient", "Mag-Lev" and Super Mass Capacity" and we quickly enter the advertising world of today's Mad Men.

Ironically any good advertising editor would tell a copyist that the first thing one should know is to know your target audience. The second thing is that if you lose that target in the opening, you will lose them completely.

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#19
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Re: Would You Travel by Vacuum-Tube Train?

09/03/2014 11:27 AM

I'm sorry if the Edison reference is inaccurate, redfred, but I believed my source (PBS) to be a reputable one. As for the image, it's not one that I drew or even labeled myself. It's from Terraspan, one of the companies discussed in the article.

I'm not an engineer, but I disagree that this is a puff piece. Maglev may sound like a buzzword, but maglev trains are used in Japan. This is not something that I made up. Perhaps the Japanese may provide their expertise here.

As for losing the audience, many readers seem to be engaged - not lost. There are 18 comments already. Granted, many are focused on the first sentence, but there has been some other discussion, too.

Hopefully, more of the audience will find the actual transportation technologies to be of interest. If not, that's OK, too. I've shared what I learned, and also learned something from you and others about Thomas Edison.

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Re: Would You Travel by Vacuum-Tube Train?

09/03/2014 12:13 PM

Maglev trains are certainly real. The efforts of Dr. Gordon Danby and Dr. James Powell are IMHO under appreciated in this country. While I did not have the privilege of working directly with either of these fine gentlemen, I did work in the same building and department as Dr. Gordon Danby for many years. This is probably what makes me so sensitive when I see their work twisted into an unreal fantasy.

One of the things that kills many new technologies are the hyperbolic exaggerations from "sales" people that promise more than the technology can possibly provide. The Shanghai maglev train travels at 250 MPH. The Japanese expertise link you cite hopes to provide just over 300 MPH velocities. Wishing to achieve velocities 20 times faster is absurd.

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#15

Re: Would You Travel by Vacuum-Tube Train?

09/03/2014 9:40 AM

A single leak in the body of the car and you're dead meat......and a slight misalignment in the tube for whatever reason, @ 4,000 MPH you go splat in a Big Way. They won't find any of your body parts, 'cause you'll be a puddle of red goo.

No thanks, I'll walk first!

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#16
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Re: Would You Travel by Vacuum-Tube Train?

09/03/2014 9:44 AM

That was one of the wayward decimal points.

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Re: Would You Travel by Vacuum-Tube Train?

09/03/2014 10:17 AM

To get from Montreal to Shanghai in under two hours requires an average speed of at least 3700 MPH. If one has a constant acceleration and deceleration this means that the peak velocity will be some 7400 MPH. To put this in perspective this peak velocity is about one quarter of the velocity we used to escape the Earth to get to the Moon.

This article is pure fluff and no substance.

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Re: Would You Travel by Vacuum-Tube Train?

09/03/2014 10:33 AM

Simpler, faster, and cheaper to use Skype.

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#21

Re: Would You Travel by Vacuum-Tube Train?

09/06/2014 8:15 AM

Definitely no question for the concept, it is efficient as friction can be neglected in the transportation of car but, the main thing is how would you maintain a vacuum in a a very long tube? Also, if the car defects a pressure seal people will be definitely at an instant bloated just like in space.

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#24
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Re: Would You Travel by Vacuum-Tube Train?

10/03/2014 3:07 AM

I'll bite, what requirement are you speculating vacuum leakage threshold would compromise the travel of vessel in the tube?

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#22

Re: Would You Travel by Vacuum-Tube Train?

09/06/2014 8:59 AM

Can't we design and build an aircraft to fly at 4000mph in an air corridor at a prescribed altitude reserved for it without sonic boom problem?.

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#23

Re: Would You Travel by Vacuum-Tube Train?

09/09/2014 7:29 AM

Might be a good way to ship "product" to reduce transportation costs of goods. Then we can all stay home and use the products!

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#25

Re: Would You Travel by Vacuum-Tube Train?

11/03/2017 10:15 AM

it will be a loss project. cause hyper tension diseased people will die, when traveling on it. osmotic pressure will be increased by the general people. after traveling (if not acclimatized) must increase vomiting tendency, migraine, headache, toothache. those who already torn their ligament, inside or outside of the body by piles/fistula, will secret huge blood. hear will also missing beats.. more N more will be changed, inside of the body. apology! i m poor in english. pl ask to the expert physicians, what will b the adverse effect by traveling on it....

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#26
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Re: Would You Travel by Vacuum-Tube Train?

11/03/2017 11:43 AM

I'm assuming that the insides of the trains are not held at vacuum, since that would suffocate the passengers.

If the cabins are pressurized (as they would need to be for passenger comfort) and the acceleration and braking are done gently enough to prevent passenger injury (as, again they would need to be), then how are people with high blood pressure dying from traveling on this?

Your comment seems on par with the "Man was never meant to travel faster than sound" / "Man was never meant to fly" / "Traveling 60 miles an hour will rip your skin off" claims made against 'new' transportation systems in the past.

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#27
In reply to #25

Re: Would You Travel by Vacuum-Tube Train?

11/05/2017 1:52 PM

Travelling in sealed pressurised vessels experiencing potentially high acceleration and deceleration forces and traveling at fantastic speeds seems to work pretty well for the astronauts and even the general public traveling on high speed trains, perhaps you are missing some key fundamental physics principles.

The same erroneous comments were also made by some many years ago that thought motorcars couldn't travel faster than something like 40 MPH (or something, I cannot remember the exact speed sorry) because the human body couldn't take it. Just a misunderstanding of the principles and actual forces involved that the body experiences.

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#28
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Re: Would You Travel by Vacuum-Tube Train?

11/05/2017 9:09 PM

When one considers the ruts, mud and other poor road surfaces a horse easily navigates and the questionable suspension system of early motorcars, 40 MPH seems like a good top speed to me.

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Re: Would You Travel by Vacuum-Tube Train?

11/05/2017 9:56 PM

No, I read an article ages ago that some people were concerned purely with the vehicle speed and wind on open-topped vehicles causing issues with early motorists, not the bumpy road surface or crashing at speed at all. They even postulated that there was a maximum top speed people could travel without physical harm (slower than todays motorway speed limit) and hence vehicles could never go faster than this, regardless of f it had an enclosed cabin.

Might have been published in popular mechanics thinking about, post WW1 pre-WW2 possibly.

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Re: Would You Travel by Vacuum-Tube Train?

11/06/2017 9:11 AM

Well we do have windshields today to keep the wind, rain, insects and other muck off of our faces and eyeballs. The early windshields did become a hazard itself when they broke. This evolved into the safety glass of today. That earlier article your remembered could just be identifying what needed to be engineered for greater than 40 MPH speeds.

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#31
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Re: Would You Travel by Vacuum-Tube Train?

11/06/2017 9:12 AM

Yeah, there was that theory that exceeding certain speeds would harm the human body, but that is (or should be) in the past, now that we understand science and physics better, it is easy to see that as long as there are no hazards within one's inertial frame of reference, that frame can be traveling at fantastic speeds to outside reference points while the occupants are fine.

What you have to look at is the ACCELERATION(1) of that inertial frame, as any change to the frame's speed gets transferred to the occupants. It's all basic derivative calculus(2):

  • Taking Position as the Base function
  • Velocity = change of Position / change of Time | (dP)/(dT) | 1st derivative of Position
  • Acceleration = change of Velocity / change of Time | (dV)/(dT) | (dP)/(dT2) | 2nd derivative of Position
  • Jerk = change of Acceleration / change of Time | (dA)/(dT) | (dP)/(dT3) | 3rd derivative of Position

And as you can see, I'm already oversimplifying, since It's not the absolute acceleration we're looking for, but the rate of change of acceleration, the Jerk. That is what we feel, the Jerk, not the Acceleration. Astronauts in the ISS are in 'free fall;' their acceleration is constant, but they feel like they are not moving at all. On Earth, you can feel the effects of Jerk when in an elevator, that moment of heaviness at the bottom of your trip and moment of lightness at the top are your body reacting to the 'jerkiness' of the elevator's start and stop. Keep the Jerk low enough and you can adjust the Acceleration to obscene levels and still keep your passengers happy and healthy(3).

Notes:

  1. Or deceleration, which is just acceleration in the opposite vector.
  2. So basic I use it to remember how to determine the nth derivative(4).
  3. That also means insuring that the curves are a large enough radius that the centripetal force (which is just another Acceleration vector) isn't changed too fast to cause discomfort/injury.
  4. I also use it when driving, keeping the factors in mind as I brake from tollway speeds down to tollbooth speeds. I've managed to freak passengers out by keeping the Jerk so low they can't feel me braking at all(5).
  5. I have mentioned that I'm a part-time Mad Scientist, I have to do one 'evil' thing a day to maintain my license. Fortunately, using my knowledge of science to harmlessly 'prank' others counts, on the technicality that it falls under 'demonstrating mental superiority over the fools(6).'
  6. I'm surprised they let that one be worded so vaguely. I could literally do a canned trick purchased from a magic shop and fulfill that requirement.
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