Euclid Zugmann, I did state that wrongly above. The brake pipe and the independents leaked down, but the tank car automatic brakes remained released with reservoirs fully pressurized because the leak down of the brake pipe was too slow to cause an application of the tank car brakes.
My understanding is that the auxilary reservoirs would have leaked down at the same rate as the train line. That's why the brakes didn't set up. Had the control valve sensed higher pressure in the auxilary reservoir then the train line, it would have moved to the application position. That's how air brakes work. (When the control valve senses pressure equalization between the TL and AXR, it goes to lap. When it senses higher pressure in the TL, it goes to release. Those three basic functions are why the control valve used to be, and the term still is used in the field, called a "triple valve.")
When in the release/running position, there is a charging port that is open between the train line and reservoir. Air can flow into or out of the reservoir. As long as the rate is light enough, it won't trigger a brake application. (The link Zug has says the train line leaked off at 1psi/minute. It wasn't enough to trigger an application.)
That port closes when the control valve goes the application position, and then to the lap position after pressure between the train line and auxilary reservoir equalizes. Before leaving the train unattendend, had the engineer made a brake application, instead of leaving the brake in the release position, the car brakes would have set up harder as the train line leaked off.
I've heard of some railroads (I think the few times I've heard of it, they were all Canadian railroads.) allowing to leave a train unattendend, with the air brakes released after tying a sufficient number of hand brakes. Most, however have rules to leave unattendend trains with the automatic brake applied.
http://www.railway-technical.com/air-brakes.shtml
Scroll down to "operation on each vehicle" and you can see the connection, called a "feed groove" if you enlarge the diagrams.
Jeff
It might bear mentioning here, before we get some 'expert' solving the problem by making the valve more sensitive, that a properly adjusted triple valve has to be relatively insensitive to the rate of changes in the line pressure. When it is sensitive, you have one kind of 'dynamiter', and that is a bad thing; how you'd get a train reliably over the road with a whole consist of them is a nightmare even to non-railroaders.
I have little doubt that if you went back and looked at the specs or design process of the EOT device, you'd find that the little air turbine was specifically designed so that it wouldn't use enough air to provoke an emergency release on cars with triples within spec. That turned out to be a tragic 'optimization' at Lac Megantic, but I don't blame the EOT's engineering team -- who among them would imagine that a train would be left with all the engines shut down, hanging on the independent and a grossly inadequate number of handbrakes, on a 2% grade?
Euclid Dave, You say that only empties have a chance of being dragged as an alternative to jackknifing, and therefore my idea won’t work because the oil trains are loaded. Yet, in the Virginia wreck, eight LOADED cars were derailed and dragged, with the first car in the string being dragged 1,200 feet. They lost their trucks and tore up the track, and yet they stayed in line, and mostly upright; and none of those eight cars breached. Then you suggest that none of this matters because cars behind the eight dragged cars did jackknife and breach, as if that discredits the idea of differential braking and related features. All the Virginia wreck did was inadvertently demonstrate the beneficial effect of differential braking. Had this train been equipped with my four features, the braking response would have begun the instant the first car derailed, rather than after it dragged for 1,200 feet. And also the braking response would have set maximum braking behind the derailed car, and due to the empty/loaded sensors of my concept, that braking would have been much greater braking force than what was available in the Virginia train wreck. At the same time, the differential braking would have created the same type of tension ahead of the derailed cars that was demonstrated inadvertently in the actual wreck. So rather than just dragging eight cars clear of the pileup; with my system, the much heavier braking behind the derailment, plus the fact that it would have begun 1,200 feet earlier—these factors may have prevented all of the jackknifing that did occur in the wreck, and also prevented all of the breaching and fire that did occur.
1) The derailed cars part as they move over damaged tracks, and the derailed cars behind the parting are being shoved ahead by the cars still on the rails behind the derailment. The derailed cars behind the parting jackknife, and the ones ahead of the derailment pull away without jackknifing.
2) The derailed cars do not part as they move over damaged track, and the slack is bunched because they are being shoved ahead by the cars still on the rails behind the derailment. The derailed cars jackknife as they are shoved.
3) The derailed cars do not part as they move over damaged track, and the slack is stretched as they are being pulled ahead by the cars still on the rails ahead of the derailment. The derailed cars do not jackknife.
Euclid In the Lynchburg wreck, the pulling was only against the resistance of the eight derailed cars because no brakes were applied to the cars behind the derailment during the dragging of the eight derailed cars.
And how do you know that to be fact?
Norm
A news item published Monday, April 20th, indicates that the Transportation Department has issued a series of emergency orders, including a 40-mph speed limit for hazardous materials moving through uban areas.
Let's face if folks - Bucky's solutions are going to save the day, and it's the railroads' fault if they don't immediately embrace and implement those solutions.
Larry Resident Microferroequinologist (at least at my house) Everyone goes home; Safety begins with you My Opinion. Standard Disclaimers Apply. No Expiration Date Come ride the rails with me! There's one thing about humility - the moment you think you've got it, you've lost it...
cacole A news item published Monday, April 20th, indicates that the Transportation Department has issued a series of emergency orders, including a 40-mph speed limit for hazardous materials moving through uban areas.
"High Thread Urban" should have been written "High Threat Urban."
Does what was posted today extend the speed reduction to all urban areas?
Johnny
tree68 Let's face if folks - Bucky's solutions are going to save the day, and it's the railroads' fault if they don't immediately embrace and implement those solutions.
The world should be beating a path to his door. He will be rich and famous.
Deggesty Does what was posted today extend the speed reduction to all urban areas?
No - only those defined by the FRA.
And in many cases, track speed in these areas are already below 40 MPH for all trains because of the lines having been laid out in the 19th Century and then they got hemmed in by urban development.
Never too old to have a happy childhood!
What truly amazes me is that the NTSB has failed to recognize the raw and apparently untapped talent Bucky has of simply looking at an video of a derailment, and without every having set foot at the wreck site, can, from far away, describe in exacting detail the movement of every car involved, and explain with such total detail the how and why each car ended up where it did, even though he has collected no evidence from the site, made no measurements, was not involved in the original investigation, or examined any of the cars involved in person.
Why they don't simply close the agency and just send videos directly to him to both explain what and how any accident happened, and to give the proper and precise solution to prevent such accident from ever happening again is beyond me.....save the government a lot of money that way.
23 17 46 11
Norm48327 tree68 Let's face if folks - Bucky's solutions are going to save the day, and it's the railroads' fault if they don't immediately embrace and implement those solutions. The world should be beating a path to his door. He will be rich and famous.
And then we can say we know someone famous.........
If I had a dime for every self-proclaimed expert like Bucky who supposedly save the day, I would be rich.
It appears that Bucky (or whatever he calls himself) is a philosophical cousin of the unlamented futuremodal, who absolutely insisted that dual-powers, Roadrailers and open access would save American railroading.
Euclid I am just somebody who sees a rising problem of exploding oil trains growing with the fast rise in crude oil traffic. So I suggest ways to solve that problem. I think solving the problem will require changing something.
Perhaps it does, but continuous hammering away at the same subject over and over without offering any practical and affordable solutions accomplishes nothing. If you had some genuine railroad credentials you would realize that. Most of your posts have been simply rewording of the previous one and looking for a different outcome. It doesn't work that way.
Do you not think the powers that be would like to have zero derailments and accidents? They surely would, but they realize there is no such thing as perfection in any endeavor. They take safety very seriously, both for employees and the public.
Norm48327 Euclid I am just somebody who sees a rising problem of exploding oil trains growing with the fast rise in crude oil traffic. So I suggest ways to solve that problem. I think solving the problem will require changing something. Perhaps it does, but continuous hammering away at the same subject over and over without offering any practical and affordable solutions accomplishes nothing. If you had some genuine railroad credentials you would realize that. Most of your posts have been simply rewording of the previous one and looking for a different outcome. It doesn't work that way. Do you not think the powers that be would like to have zero derailments and accidents? They surely would, but they realize there is no such thing as perfection in any endeavor. They take safety very seriously, both for employees and the public.
+1
Prevention must be zero tolerance, absolute; given the nature of Bakken crude oil.Bakken crude oil is a stratified multi constituent liquid. Its weight is such that something like 28,000 gallons are the weight limit for a 30,000 gallon tank car. Visualize the 2000 gallons as about 36 drums of 55 gallon capacity. That's quite a bit of empty space inside a tank car. It is about 269 cubic feet. What is the factor of cargo sloshing in the tank cars? What are the fluid dynamics for a stratified liquid such as Bakken crude? How does the distributed inertia and viscosity of Bakken crude contribute to unstable vehicle dynamics and rail/ wheel interaction? Might skin friction result in the tank due to sloshing creating localized heating, stress and failure? Are boiling liquid expanding vapor events (BLEVE) causing the derailments?Are the braking dynamics of ordinary air brakes contributing to slosh and a series of events leading to failure? Is there an optimal speed of operation for Bakken crude? Is there a maximum number of tank cars not to be exceeded? Is the draft gear and energy absorption of the tank cars adequate for handling Bakken crude.These are the questions must be examined.
The inherent problem with railroad tank cars is that they are stupid. That is, there are no sensors on the tank cars to identify what the cargo is doing and how it affects vehicle dynamics. Knowing what is going on n the tank is first and foremost needed.
FRA PHMSA announcement simplly dela with stupid vehicles, rail tank cars. Given the potential and reality for catastrophe smart railroad cars need to part of the problem solving.
I don’t know if you realize this, but the collection of ideas that I am proposing are not just unproven concepts that I have come up with in a vacuum. ECP brakes, empty/loaded sensors, derailment sensors, and solid drawbars are all well-established concepts in practical use with proven merit.
The question you haven't asked, or have accepted a simplistic answer for, is if all these technologies have been around for decades and have been tried at various times in various places around the world, why haven't they been adopted by more (any) railroads or car manufacturers on a regular basis? If professional people in the industry who have access to more data and can actually research these alternatives have not adopted them there must be a reason. Railroads have adopted lots of new technology over the last 3 or 4 decades (fiber optics, solid state, new detection systems, DPU, shelf couplers, head shields, energy management systems, new truck designs, new track standards, CWR, etc., etc.) but for some reason (or reasons) have not adopted your favorite "solutions". What that should tell you is there are barriers, downsides, consequences to those "solutions" that make them unattractive. Those are off the shelf "solutions", until something mitigates the barriers, downsides and consequences, those "solutions" will continue to be passed over.
Dave H. Painted side goes up. My website : wnbranch.com
dehusmanWhat that should tell you is there are barriers, downsides, consequences to those "solutions" that make them unattractive. Those are off the shelf "solutions", until something mitigates the barriers, downsides and consequences, those "solutions" will continue to be passed over.
Bingo!!!
Cue the "yes, but..."
Euclid What you seem to be saying is the old fallacy that if a new idea was worthwhile it would have already been invented.
That is not what he is saying at all. Perhaps some of your ideas have already been tried and found to be unworkable without further refinement or new technology.
You are ignoring everything that has been posted in response to you; "Two track railroad, one track mind" syndrome. It's time for you to acknowledge that others have valid arguments. Until you can do that your posts are nothing more than trolling. Adiscussion involves both sides. You're not listening to the other side.
WilliamKiesel Prevention must be zero tolerance, absolute; given the nature of Bakken crude oil.Bakken crude oil is a stratified multi constituent liquid. Its weight is such that something like 28,000 gallons are the weight limit for a 30,000 gallon tank car. Visualize the 2000 gallons as about 36 drums of 55 gallon capacity. That's quite a bit of empty space inside a tank car. It is about 269 cubic feet. What is the factor of cargo sloshing in the tank cars? What are the fluid dynamics for a stratified liquid such as Bakken crude? How does the distributed inertia and viscosity of Bakken crude contribute to unstable vehicle dynamics and rail/ wheel interaction? Might skin friction result in the tank due to sloshing creating localized heating, stress and failure? Are boiling liquid expanding vapor events (BLEVE) causing the derailments?Are the braking dynamics of ordinary air brakes contributing to slosh and a series of events leading to failure? Is there an optimal speed of operation for Bakken crude? Is there a maximum number of tank cars not to be exceeded? Is the draft gear and energy absorption of the tank cars adequate for handling Bakken crude.These are the questions must be examined. The inherent problem with railroad tank cars is that they are stupid. That is, there are no sensors on the tank cars to identify what the cargo is doing and how it affects vehicle dynamics. Knowing what is going on n the tank is first and foremost needed. FRA PHMSA announcement simplly dela with stupid vehicles, rail tank cars. Given the potential and reality for catastrophe smart railroad cars need to part of the problem solving.
Great post of some good, fact-based questions.
C&NW, CA&E, MILW, CGW and IC fan
Norm48327 Euclid What you seem to be saying is the old fallacy that if a new idea was worthwhile it would have already been invented. That is not what he is saying at all. Perhaps some of your ideas have already been tried and found to be unworkable without further refinement or new technology.
EuclidYou and Dave are saying that since you are not seeing my ideas adopted, that has to mean that some hypothetical expert has proven that my ideas are not viable.
As opposed to the hypothetical expert who is insisting that they are.
I've got an idea. Rather than defend your ideas against all evidence to the contrary, why not give it a rest for say, a year. Then if any of your ideas are adopted you can come back and say "I told you so."
Of course, if they aren't, you are completely welcome to come back and admit failure, too.
Standing by for "yes, but..."
Yes, but.....
Bucky,
I see no need for further discussion of the matter. You abjectly refuse to admit you may be wrong or others may have a valid point.
This discussion, however, needed to be done in the open forum so that you could see there are many folks here who disagree with you.
Over and out!
EuclidSo, why don’t you guys go and start your own thread about everything that is wrong with me instead of hijacking this one?
Because at this point there is no further reason to continue the discussion. Your ideas have been aired, folks have pointed out potential shortcomings of same, and you simply reply by restating the same things over and over again.
As we've seen many times, you simply won't take "no" for an answer, regardless of what others may offer.
You insist on restating your claims over and over, perhaps in hope that if you say them often enough, people will start to believe you. So far, that hasn't happened. You should take something from that other than "people won't listen."
Einstein wisely noted, "Insanity: doing the same thing over and over again and expecting different results."
And so it goes with you - you throw your ideas and theories out there again and again, and again, and again.
Of course, that makes the rest of us a little crazy, as we've tried over and over to show you the fallacies in what you present, to no avail.
And one last note on the original topic - the feds foisted a technology on the railroads that couldn't even be implemented because so many parts were missing. What makes you think that they wouldn't have mandated established technologies with regard to oil trains?
Don't answer that. Just kick back and take a little vacation.
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