NorthWest I don't think actual speeds will increase, but ECP's quicker brake application and release rates will allow trains to travel at track speed for longer and thus get over the road faster.
I don't think actual speeds will increase, but ECP's quicker brake application and release rates will allow trains to travel at track speed for longer and thus get over the road faster.
Don't count on it with the implementation of PTC and the use of 'Trip Optimizer' and similar applications.
Never too old to have a happy childhood!
On a visit to Jilalan in Central Queensland a few years ago, when Pacific National had just started running their ECP trains and Aurizon were only operating non ECP trains, I was waiting at the north end of this big yard to photograph coal trains on their way to Dalrymple Bay (the second largest coal export port in Australia).
Owing to congestion at the port, these trains may have to stop at any of four or five signals between the yard and the port, and the Aurizon trains with their three electric locomotives crept through at maybe ten miles an hour ready to stop at any signal ahead.
The Pacific National trains rolled through at 30 miles an hour, not track speed but relatively much faster. I recall this because I missed a photo of the PN train as I'd not left myself enough time to get in position.
The difference was that the ECP train could run faster confident that it could stop in a much shorter distance without damage to the train.
Another demonstation in the Hunter Valley was a signal failure at Tarro. At the time, there was a crossover to allow loaded trains to use the westbound (empty) track if the eastbound (loaded) track was congested with standing loaded trains.
I had observed a signal technician working at the crossover and the associated westbound signal protecting the crossover.
An Aurizon westbound empty coal train approached pretty much at track speed (50 MPH for unit trains) and headed under the road bridge I was standing on.
The next thing I noticed, as I turned to look at the receding train was that the westbound train had stopped well clear of the crossover signal. There was no run in or even noticeable noise. The train just stopped silently from 50 MPH in less than its length (it was empty).
I looked at the signal and it was displaying red, amber and green aspects at about one second intervals in succession continuously. It is clear why the train made what must have been an emergency stop, but it did so without any longitudinal train action and it departed without a single skidded wheel as soon as Control explained that the track was clear and the signal had failed.
Both these examples support North West's contention that trains will get over the road faster with ECP braking.
And remember, this isn't theory. These trains run like this every day, and the owners are happy to spend whatever extra it costs to get both the improved performance and the reduced maintenance. Suppose the train affected by the failed signal had been a conventional train with eighty empty hoppers. Even with the relatively new Westinghouse equipment with empty/loaded detection, I don't imagine they would have avoided a few skidded wheels in an emergency stop from 50 MPH.
None of this is theory. It works every day. The equipment comes from US suppliers like Wabco. It is off the shelf. All you have to do is buy it and watch your operating costs fall away.
M636C
M636C Euclid Backing up a bit: Does anybody have a further explanation or a link to information about using an EOT to mirror a service application of air brakes when one is initiated from the cab? Would an End of Train Device be able to replicate all of the actions of a locomotive brake controller? It would need a pretty complex air brake valve and serious control data arriving by radio link... Has anyone done a survey to see if Railroads resisted the Westinghouse automatic air brake when first intoduced as seriously as they are trying to avoid ECP brakes. All these suggestions about how to get a result not quite as good as ECP by adding complications to the existing system sound like saying that by using more brakemen spaced down the train and developing a better set of whistle signals would give you a result nearly as good as air brakes (as an excuse for not adopting air brakes).....
Euclid Backing up a bit: Does anybody have a further explanation or a link to information about using an EOT to mirror a service application of air brakes when one is initiated from the cab?
Would an End of Train Device be able to replicate all of the actions of a locomotive brake controller? It would need a pretty complex air brake valve and serious control data arriving by radio link...
Has anyone done a survey to see if Railroads resisted the Westinghouse automatic air brake when first intoduced as seriously as they are trying to avoid ECP brakes.
All these suggestions about how to get a result not quite as good as ECP by adding complications to the existing system sound like saying that by using more brakemen spaced down the train and developing a better set of whistle signals would give you a result nearly as good as air brakes (as an excuse for not adopting air brakes).....
Just to be clear, I was not advocating such an EOT alternative to ECP. I agree with your assessment of the complications of making a service application with the EOT that mirrors one made from the head end. I mentioned those complications earlier. My point in asking for further information was simply to see verification that such a system has been in use, as was said to be the case by someone earlier.
Why do you think there is reluctance to adopt ECP for the U.S. railroad system?
Euclid My point in asking for further information was simply to see verification that such a system has been in use, as was said to be the case by someone earlier. Why do you think there is reluctance to adopt ECP for the U.S. railroad system?
My point in asking for further information was simply to see verification that such a system has been in use, as was said to be the case by someone earlier.
M636C All the Australian equipment involved uses couplers and brakes that reflect AAR standards and the ECP equipment is from US suppliers. It is no more difficult to convert to ECP in the USA than Australia but in Australia, much, maybe most of the total freight task by weight is carried on ECP trains while in the USA, as far as I can tell none is.... If there is a positive return on investment from ECP in Australia, the same must apply in the USA. So why is there a ten year lead in applying ECP brakes in Australia? The only reason I can see is reluctance by US railroads to use equipment they could buy off the shelf, today, in large enough quantities from US suppliers to fit entire unit trains they are already operating. M636C
http://cs.trains.com/trn/b/fred-frailey/archive/2015/05/13/railroads-and-their-money.aspx
(Fred Frailey blog May 13,2015)
Euclid The Cartier Railway in Canada uses ECP brakes: http://www.canadianminingjournal.com/features/quebec-cartier-pioneers-safer-more-efficient-railroad-brakes/ Clearly ECP offers benefits, but there is one factor of performance that I believe has been misrepresented in bad faith. That factor is stopping distance. ECP is typically promoted as offering a dramatic reduction in stopping distance. But the claim carefully avoids the condition that it only applies to “Service” applications. For “Emergency” applications, the ECP stopping distance advantage is minor. It is an odd stipulation that would only come into play with train brakes. For any other type of vehicle, “stopping distance” naturally implies “shortest stopping distance.” So I conclude that ECP promoters have been intentionally disingenuous in the claim of shortening stopping distance. Perhaps that is one reason why we now have an ECP mandate for oil trains.
M636C I was on a Rio Tinto (then called Hamersley Iron) iron ore train that made an emergency application in 1978. The train was within sight of the "Seven Mile" yard when the yard controller changed his mind about which track we were to use and a signal reversed from green to red as we approached at about 40 MPH. To avoid passing the signal at red, the driver applied emergency braking. The train consisted of a C36-7 leading and two M636 with 220 cars carrying 100 long tons of ore each. These cars were married pairs with drawbars, so there were only 110 triple valves. It was a warm fine clear day. The load behind the locomotives would have been around 25 000 long tons. We were lucky not to derail. The train broke in five places, one being a drawbar that pulled out of a broken yoke. Fortunately we were on double track so we didn't block the line but it took hours to get the train into the yard. M636C
First off - whoever took the signal down without contacting the engineer of the train to see if he could make a controlled stop of the train BEFORE passing the signal should be FIRED! Taking a signal away without notice is a sure way to create the mess you discribed - no matter the braking system.
M636CPerhaps many USA railroad managers have never been on a locomotive
Fixed that for you.
Norm
M636C Euclid The Cartier Railway in Canada uses ECP brakes: http://www.canadianminingjournal.com/features/quebec-cartier-pioneers-safer-more-efficient-railroad-brakes/ Clearly ECP offers benefits, but there is one factor of performance that I believe has been misrepresented in bad faith. That factor is stopping distance. ECP is typically promoted as offering a dramatic reduction in stopping distance. But the claim carefully avoids the condition that it only applies to “Service” applications. For “Emergency” applications, the ECP stopping distance advantage is minor. It is an odd stipulation that would only come into play with train brakes. For any other type of vehicle, “stopping distance” naturally implies “shortest stopping distance.” So I conclude that ECP promoters have been intentionally disingenuous in the claim of shortening stopping distance. Perhaps that is one reason why we now have an ECP mandate for oil trains. That Quebec Cartier reference is nine years old.... There are four similar railroads in Australia that are fully ECP: BHP Billiton, Rio Tinto, Fortescue and Roy Hill. But none in the USA? Is shortening the stopping distance the only measure of merit for emergency braking?
You ask why U.S. railroads are not enthused about ECP. Whatever their reasons, I would say they elaborated on them with the greatest clarity in the month or so leading up to the oil train ECP mandate. Prior to that, I don’t recall much argument against ECP.
Don't locomotives still have independent brakes? The engineer must be sure to use the train brake if he needs to stop quickly. Fifty-three years ago, I was going up to Bristol on the Pelican. Just before we were ready to leave Birminghm by heading out to the main, an L&N train began coming down to the crossing with the Southern--and the L&N gate watchman threw the gate across the Southern track almost in the face of the engineer of a freight that was headed for Sheffield. Sad to say, the engineer of the Southern freight must have had his hand on the independent brake valve, for he stopped the engine in time--and derailed some of the cars and blocking both tracks to the main. As it was, we were able to back to North Birmingham and then use another track to Woodlawn Junction and take the main from there. I do not doubt that the L&N watchman and the Southern engineer were spoken to sharply.
Johnny
BaltACD First off - whoever took the signal down without contacting the engineer of the train to see if he could make a controlled stop of the train BEFORE passing the signal should be FIRED! Taking a signal away without notice is a sure way to create the mess you discribed - no matter the braking system.
I wasn't involved in the enquiry followng the incident but I believe they started off by blaming the locomotive crew.
The operator in the yard tower should have been able to see our headlight although he might not have realised how close we were.
The same situation can be created by a motor vehicle driving onto a grade crossing without looking.
My view is that the yard controller was at fault, but my point was that the stopping distance in emergency braking is not the only consideration. Emergency is just that. It isn't one more step in controlled braking, it is intended for life or death situations and the current air brake system does an excellent job of stopping a train in a minimum distance.
I've seen ECP trains stop just as quickly. What impressed me was the much greater degree of control during maximum braking.
The same sort of yo-yo effects occur on the road every time a long train brakes, and problems can occur in starting if the rear of the train hasn't released its brakes by the time it starts moving.
I actually had instrumented couplers measuring train forces on that particular train but of course the equipment was turned off at the time. I would have loved to know what the forces were. It might not have been recorded anyway. There was 2000 metres of coaxial cable strung down the side of the train which just disappeared in the whiplash. We never found any of it and it cost then a dollar per metre.
Euclid What difference does it make how old the Cartier reference is? It is still pertinent. And is also making your argument. In any case, I was not offering the reference to Cartier as part of a competition between the U.S. and Australia. Regarding your question as to whether stopping distance is the only measure of merit: No, there are other measures of merit, but again, I was not referring to stopping distance as part of a compilation of pros and cons in a competition between ECP and conventional air brakes. I have no stake in either one. My point was only about stopping distance, and my feeling that it has been used to misrepresent ECP. The stopping distance is around 5% shorter with ECP in the “Emergency” application, as you say. But I have seen many references that simply state that the stopping distance with ECP is around 60-70% less than with conventional air brakes. They never say that is the stopping distance for “Service” applications only. Regardless of all the other benefits, quick stopping is the one that the most people can relate to in regard to safety concerns. And at the same time, they will have absolutely no clue that there are TWO different kinds of stopping distance. As you must know, the U.S. railroads vigorously argued against the need for ECP brakes on oil trains when the mandate loomed up. Their strongest argument was that the conventional air brakes could stop in “Emergency” almost as quickly as ECP brakes; if the train with conventional air brakes were equipped to dump the air from the road engine, the EOT, and the distributed power locomotives simultaneously. You ask why U.S. railroads are not enthused about ECP. Whatever their reasons, I would say they elaborated on them with the greatest clarity in the month or so leading up to the oil train ECP mandate. Prior to that, I don’t recall much argument against ECP.
As far as this poster can see the jury is still out on ECP. However maybe it needs to be looked at in a different way. It may be mixed freight trains need ECP much more than unit trains.
1. Unit trains of Coal, grain, oil, iron ore, pipe line, and to a lesser extent intermodal all share common characteristics.
2. They are all either full cars or empty tare weight cars throughout the train.
3. Weight of each car for a specific train is nominally the same.
4. Normal hearing of a train allows observer to determine if a unit train.
5. The lack of the usual rattling of a mixed train is usually only on none or just a few cars for unit trains.
It may be the triple valves on unit trains do not cause many flat wheels ? The ECP appears to reduce triple valve failures of individual cas. So if mixed trains had ECP then maybe there would be much fewer flat wheels which could dramatically reduce wheel changes ? Since many unit trains are private cars there is not incentative of freigh RRs to require ECP on private car trains. Their repair costs may be a profit center for the RRs ?
.Along that train of thought maybe the RR owned cars might give more bang for the buck ?
ECP may offer a reduction of stopping distance, but most of the time - who cares?
Would you spend an extra 10% on an automobile that had special equipment that allowed you to stop just that much faster and extended the life of your brakes and tires by some amount?
Or would you settle for planning ahead as you do now and being able to stop in the current distances? Do you spend so much on brake shoes/pads and tires that the extended life would pay for the extra cost of the fancy system?
ECP may somewhat increase capacity slightly on capacity constrained lines - but if a line only entertains a few trains a day, that's no advantage. If a line is signalled for a certain speed and train spacing, it doesn't really make a difference.
Maybe after PTC is fully implemented on capacity contrained lines, allowing slightly closer train spacing...
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...
M636CEven if ECP does nothing to reduce emergency stopping distances, it might result in fewer cars derailing in an emergency brake application since the influence of longitudinal train action ir removed from the equation. Since derailments of oil trains is the problem to be avoided, ECP braking can only help.
tree68 ECP may offer a reduction of stopping distance, but most of the time - who cares? Would you spend an extra 10% on an automobile that had special equipment that allowed you to stop just that much faster and extended the life of your brakes and tires by some amount? Or would you settle for planning ahead as you do now and being able to stop in the current distances? Do you spend so much on brake shoes/pads and tires that the extended life would pay for the extra cost of the fancy system?
Suppose this car needed a dealer service every six months which you had to pay for, but by buying the special equipment this stretched out to every two years with the same cost per servicing.
And you found that you could get where you were going consistently in 75% of the time you took without the special equipment.
Would you think twice?
Suppose that in the case of unit coal trains being able to run faster allows one more return trip per week, say nine rather than eight, your return on investment has gone up 12.5%.
On a couple of occasions on different systems, I've been driving alongside empty ECP coal trains on a parallel road where the road and rail speed limits were similar and watched as the empty coal trains accelerated away from a restriction quickly (not having to wait for the final cars to release) and drew well away from me while I was driving slightly above the speed limit.
In both cases, the locomotives were new and their speed indicators probably read low because of new slightly oversize wheels...
I can't think of any cases where the same occurred with Westinghouse trains.
The higher speed and greater availability do count...
M636C tree68 ECP may offer a reduction of stopping distance, but most of the time - who cares? Would you spend an extra 10% on an automobile that had special equipment that allowed you to stop just that much faster and extended the life of your brakes and tires by some amount? Or would you settle for planning ahead as you do now and being able to stop in the current distances? Do you spend so much on brake shoes/pads and tires that the extended life would pay for the extra cost of the fancy system? Suppose this car needed a dealer service every six months which you had to pay for, but by buying the special equipment this stretched out to every two years with the same cost per servicing. And you found that you could get where you were going consistently in 75% of the time you took without the special equipment. Would you think twice? Suppose that in the case of unit coal trains being able to run faster allows one more return trip per week, say nine rather than eight, your return on investment has gone up 12.5%. On a couple of occasions on different systems, I've been driving alongside empty ECP coal trains on a parallel road where the road and rail speed limits were similar and watched as the empty coal trains accelerated away from a restriction quickly (not having to wait for the final cars to release) and drew well away from me while I was driving slightly above the speed limit. In both cases, the locomotives were new and their speed indicators probably read low because of new slightly oversize wheels... I can't think of any cases where the same occurred with Westinghouse trains. The higher speed and greater availability do count... M636C
M636C,
Do they use derailment sensors on the car trucks of the ECP-equipped trains in Australia?
M636CSuppose that in the case of unit coal trains being able to run faster allows one more return trip per week, say nine rather than eight, your return on investment has gone up 12.5%.
Methinks this is where the ROI is - on unit trains. With loose car railroading, the "who cares" factors in. I've read that for many customers, it's not the speed with which the load arrives, it's the consistency. The length of the trips makes a difference, too.
If ECP can do something about terminal dwell, then your 75% faster factors in. Otherwise, the car just gets to the yard that much faster - so it can sit or otherwise be processed.
And speed has less to do with ECP and more to do with the capabilities of the track over which the trains run. That new, fancy brake system in my personal vehicle won't get me to where I'm going in 75% of the time unless the state decides to raise the speed limits. And if I'm running a little 4 cylinder engine in my Rolls Kanardly, it doesn't make any difference how quickly the brakes release.
I'm sure ECP will have its day - probably when PTC increases capacity.
tree68 I'm sure ECP will have its day - probably when PTC increases capacity.
And when pigs get airborne with their own aerodynamics and propulsion.
Euclid M636C, Do they use derailment sensors on the car trucks of the ECP-equipped trains in Australia?
I've never seen a derailment sensor on any freight car truck...
Lots of empty/loaded detectors, but that's it.
In my statements earlier I was assuming the automatic feature of an emergency application following a break in the air pipe would initiate braking on all cars before and after the break instantaneously, reducing the run in and force on the derailed cars from the following cars still on the track.
While this automatic braking would also occur with a conventional train, the reduction in delay for the braking to take effect on the following cars should reduce damage in a derailment.
tree68 M636C Suppose that in the case of unit coal trains being able to run faster allows one more return trip per week, say nine rather than eight, your return on investment has gone up 12.5%. Methinks this is where the ROI is - on unit trains. With loose car railroading, the "who cares" factors in. I've read that for many customers, it's not the speed with which the load arrives, it's the consistency. The length of the trips makes a difference, too. If ECP can do something about terminal dwell, then your 75% faster factors in. Otherwise, the car just gets to the yard that much faster - so it can sit or otherwise be processed. And speed has less to do with ECP and more to do with the capabilities of the track over which the trains run. That new, fancy brake system in my personal vehicle won't get me to where I'm going in 75% of the time unless the state decides to raise the speed limits. And if I'm running a little 4 cylinder engine in my Rolls Kanardly, it doesn't make any difference how quickly the brakes release. I'm sure ECP will have its day - probably when PTC increases capacity.
M636C Suppose that in the case of unit coal trains being able to run faster allows one more return trip per week, say nine rather than eight, your return on investment has gone up 12.5%.
All of my arguments are based on fitting ECP to unit trains, partly because that is all I have any experience with.
Many of the Hunter Valley unit coal trains make a return trip in 24 hours or less.
Those in Queensland generally run further with longer journeys.
In the Hunter Valley, the trains are all hopper cars with automatically triggered air operated bottom doors and the trains move continuously through both the loader and unloaders. Unloading takes about two hours for 80 cars carrying 100 tonnes (about 110 US tons) each. There are about ten separate unloaders.
Recently five storage tracks were built for loaded trains to allow for delay at the unloaders without tying up the main lines.
A lot of the journey time for a freight train is involved in stopping at junction points or at signals while following other trains. ECP trains and conventional trains run interspersed with eachother. Being able to accelerate from a signal check more quickly using the power you already have reduces the delay for following trains regardless of the brakes they use.
I'm sure you've experienced the "compression effect" driving on a freeway where long after some event caused a car to brake, following cars slow and speed up again. On double track automatic signalled track (which makes up a lot of the Australian coal routes) ECP brakes reduce delays to following trains. In Queensland where a lot of the network is electrified, this effect is greater still.
So in the case of unit trains, I believe ECP brakes reduce journey time without the top speeds needing to be raised.
blue streak 1 As far as this poster can see the jury is still out on ECP. However maybe it needs to be looked at in a different way. It may be mixed freight trains need ECP much more than unit trains. 1. Unit trains of Coal, grain, oil, iron ore, pipe line, and to a lesser extent intermodal all share common characteristics. 2. They are all either full cars or empty tare weight cars throughout the train. 3. Weight of each car for a specific train is nominally the same. 4. Normal hearing of a train allows observer to determine if a unit train. 5. The lack of the usual rattling of a mixed train is usually only on none or just a few cars for unit trains. It may be the triple valves on unit trains do not cause many flat wheels ? The ECP appears to reduce triple valve failures of individual cas. So if mixed trains had ECP then maybe there would be much fewer flat wheels which could dramatically reduce wheel changes ? Since many unit trains are private cars there is not incentative of freigh RRs to require ECP on private car trains. Their repair costs may be a profit center for the RRs ? .Along that train of thought maybe the RR owned cars might give more bang for the buck ?
I would agree that manifest trains, with mixed equipment types might benefit more from ECP. It would aid in controlling slack for trains that have a lot of long/cushioned drawbars. Especially when they want to build them 9000 feet or more.
Jeff
M636C Euclid M636C, Do they use derailment sensors on the car trucks of the ECP-equipped trains in Australia? I've never seen a derailment sensor on any freight car truck... Lots of empty/loaded detectors, but that's it. In my statements earlier I was assuming the automatic feature of an emergency application following a break in the air pipe would initiate braking on all cars before and after the break instantaneously, reducing the run in and force on the derailed cars from the following cars still on the track. While this automatic braking would also occur with a conventional train, the reduction in delay for the braking to take effect on the following cars should reduce damage in a derailment. M636C
jeffhergert blue streak 1 It may be the triple valves on unit trains do not cause many flat wheels ? The ECP appears to reduce triple valve failures of individual cas. So if mixed trains had ECP then maybe there would be much fewer flat wheels which could dramatically reduce wheel changes ? Since many unit trains are private cars there is not incentative of freigh RRs to require ECP on private car trains. Their repair costs may be a profit center for the RRs ? .Along that train of thought maybe the RR owned cars might give more bang for the buck ? I would agree that manifest trains, with mixed equipment types might benefit more from ECP. It would aid in controlling slack for trains that have a lot of long/cushioned drawbars. Especially when they want to build them 9000 feet or more. Jeff
blue streak 1 It may be the triple valves on unit trains do not cause many flat wheels ? The ECP appears to reduce triple valve failures of individual cas. So if mixed trains had ECP then maybe there would be much fewer flat wheels which could dramatically reduce wheel changes ? Since many unit trains are private cars there is not incentative of freigh RRs to require ECP on private car trains. Their repair costs may be a profit center for the RRs ? .Along that train of thought maybe the RR owned cars might give more bang for the buck ?
I'm not sure why general freight trains would benefit more from ECP.
The car utilisation is much lower and the return on investment would take longer to occur since the brakes and wheels and couplers and draft gear will last longer on individual cars.
The cost would be higher since virtually all the freight cars in North America would have to be fitted with ECP before it could be used in general freight trains and the introduction date would move so far right to be out of sight.
However, a unit train can start using ECP once one rake of cars (say 100) have been fitted and compatible locomotives are available. Most recent locomotive have brake controllers suitable for ECP. just needing the connecting cables to be fitted.
There may be more benefits in fitting general freight but the cost will be higher and timescales will be longer.
M636C jeffhergert blue streak 1 It may be the triple valves on unit trains do not cause many flat wheels ? The ECP appears to reduce triple valve failures of individual cas. So if mixed trains had ECP then maybe there would be much fewer flat wheels which could dramatically reduce wheel changes ? Since many unit trains are private cars there is not incentative of freigh RRs to require ECP on private car trains. Their repair costs may be a profit center for the RRs ? .Along that train of thought maybe the RR owned cars might give more bang for the buck ? I would agree that manifest trains, with mixed equipment types might benefit more from ECP. It would aid in controlling slack for trains that have a lot of long/cushioned drawbars. Especially when they want to build them 9000 feet or more. Jeff I'm not sure why general freight trains would benefit more from ECP. The car utilisation is much lower and the return on investment would take longer to occur since the brakes and wheels and couplers and draft gear will last longer on individual cars. The cost would be higher since virtually all the freight cars in North America would have to be fitted with ECP before it could be used in general freight trains and the introduction date would move so far right to be out of sight. However, a unit train can start using ECP once one rake of cars (say 100) have been fitted and compatible locomotives are available. Most recent locomotive have brake controllers suitable for ECP. just needing the connecting cables to be fitted. There may be more benefits in fitting general freight but the cost will be higher and timescales will be longer. M636C
Train Handling.
Euclid M636C I agree that the simultaneous application of ECP brakes would give an advantage over conventional air brakes in reducing the number of cars that enter a pileup resulting from a derailment. Even though that quicker stopping advantage of ECP is only a matter of 4-6 seconds; that is a major advantage in the timespan of a pileup. Derailment sensors can add to that ECP advantage by eliminating the delay between the first wheelset to leave the rails, and the moment the pileup begins. Derailment sensors can add a similar advantage with conventional air brakes, but ECP offers the communications cable to communicate the derailment sensor signal to the controller that sets an “Emergency” application. Without the instant communication of the cable, derailment sensors with conventional air brakes typically work to dump the air on the first car to derail, and being the typical sequential application. The potential slack run-in associated with this sequential “Emergency” application might actually trigger a pileup in a derailment that might otherwise not progress beyond the derailed-dragging phase. With conventional air brakes, the pileup has to begin before the brake application can begin. With ECP + derailment sensors, the application begins when the first wheelset derails which might be considerably earlier than the commencement of the pileup. In some cases, the earlier application of ECP can actually prevent the pileup from beginning, as well as reducing the pileup if it does begin.
I agree with every point here.
As I've said, I've not seen a derailment detector on a car.
There are fixed "dragging equipment detectors" which consist of cast iron bars beside and between the rails which wil be broken by a derailed wheel and send an alarm to the train crew and train controller.
Derailments are not a really big problem in Australia, certainly not with unit trains, although clearing up a loaded iron ore train which derails in a deep rock cutting is a real challenge.
Heavy rain undermining track is a problem. We had two bad incidents, a block train of concentrated sulphuric acid derailed the locomotive and thirty cars, all of which were on their sides and one tank car lost its load into the local river....
And an intermodal train rolled onto its side in remote Western Australia following heavy rain.
But derailment detectors of any kind don't help once the locomotives are lying on their side in the dirt.
In Australia the track is owned by the state governments and the main lines are maintained by the Federal government (what could possibly go wrong, I hear you say!).
One result of this is strict control of axle loading: Intermodal trains are allowed 22 long (2240lb) tons, grain is allowed 23 long tons and coal is allowed 25 tons or 30 tons on specific routes with heavier rail.
When the Federal government took over, a massive campaign to improve track took place with concrete ties on all main lnes and the replacement of automatic semaphore signalling (about a hundred years old) with LED light signals.
In some places, only a third of the ties were able to be pulled out without crumbling to dust. The ballast was basically dirt with a covering of crushed rock. Serious ballast cleaning is still taking place, but the removal of temporary speed restrictions, particularly in summer for fear of heat kinks has saved hours on the main intercity trips.
But I believe that limiting track loadings and improving the infrastructure has contributed to a significant reduction in "random" derailments.
M636C Euclid M636C I agree that the simultaneous application of ECP brakes would give an advantage over conventional air brakes in reducing the number of cars that enter a pileup resulting from a derailment. Even though that quicker stopping advantage of ECP is only a matter of 4-6 seconds; that is a major advantage in the timespan of a pileup. Derailment sensors can add to that ECP advantage by eliminating the delay between the first wheelset to leave the rails, and the moment the pileup begins. Derailment sensors can add a similar advantage with conventional air brakes, but ECP offers the communications cable to communicate the derailment sensor signal to the controller that sets an “Emergency” application. Without the instant communication of the cable, derailment sensors with conventional air brakes typically work to dump the air on the first car to derail, and being the typical sequential application. The potential slack run-in associated with this sequential “Emergency” application might actually trigger a pileup in a derailment that might otherwise not progress beyond the derailed-dragging phase. With conventional air brakes, the pileup has to begin before the brake application can begin. With ECP + derailment sensors, the application begins when the first wheelset derails which might be considerably earlier than the commencement of the pileup. In some cases, the earlier application of ECP can actually prevent the pileup from beginning, as well as reducing the pileup if it does begin. I agree with every point here. As I've said, I've not seen a derailment detector on a car. There are fixed "dragging equipment detectors" which consist of cast iron bars beside and between the rails which wil be broken by a derailed wheel and send an alarm to the train crew and train controller. Derailments are not a really big problem in Australia, certainly not with unit trains, although clearing up a loaded iron ore train which derails in a deep rock cutting is a real challenge. Heavy rain undermining track is a problem. We had two bad incidents, a block train of concentrated sulphuric acid derailed the locomotive and thirty cars, all of which were on their sides and one tank car lost its load into the local river.... And an intermodal train rolled onto its side in remote Western Australia following heavy rain. But derailment detectors of any kind don't help once the locomotives are lying on their side in the dirt. In Australia the track is owned by the state governments and the main lines are maintained by the Federal government (what could possibly go wrong, I hear you say!). One result of this is strict control of axle loading: Intermodal trains are allowed 22 long (2240lb) tons, grain is allowed 23 long tons and coal is allowed 25 tons or 30 tons on specific routes with heavier rail. When the Federal government took over, a massive campaign to improve track took place with concrete ties on all main lnes and the replacement of automatic semaphore signalling (about a hundred years old) with LED light signals. In some places, only a third of the ties were able to be pulled out without crumbling to dust. The ballast was basically dirt with a covering of crushed rock. Serious ballast cleaning is still taking place, but the removal of temporary speed restrictions, particularly in summer for fear of heat kinks has saved hours on the main intercity trips. But I believe that limiting track loadings and improving the infrastructure has contributed to a significant reduction in "random" derailments. M636C
Euclid The main point of derailment detectors is to set the brakes as early as possible. The type that are completely mechanical and used with conventional air brakes, must dynamite the brakes if they detect a derailment. That has the potential to perturb the derailed-dragging car enough to cause a pileup, whereas, if left to drag without the “Emergency” application, the train may just stop for some other reason, resulting in the derailment being discovered. Last summer, a tank car load of acrylonitrile caught fire on the CSX in Tennessee. As it was later learned, that car had been derailed and dragging for NINE MILES. A derailment detector would have stopped the train as soon as the car derailed, and thus prevented the eventual fire that started from friction in the derailed truck. The benefit of combining derailment detectors with ECP is that there need not be an emergency application initiated upon derailment. A lighter application could be made in order to not upset the fragile equilibrium of a derailed-dragging car. Even if an “Emergency” application were initiated, it would apply simultaneously throughout the train, and thus reduce the risk of slack run-in perturbing the derailed-dragging car into causing a pileup.
I'm certainly not opposed to derailment detectors, I've just never seen one....
Do many US freight cars carry these detectors?
It would seem to be a good idea to equip new oil tank wagons with these devices as a standard fit, given the likelihood of avoiding some derailment accidents.
Of course, the Lac Megantic disaster would not have been avoided by a derailment detector, since by the time the derailment occured, the unmanned train was travelling at a high speed and by definition was out of control.
The combination of ECP braking and derailment detectors on all cars of a block oil train would have positive results in the case of rails breaking under the train or an axle bearing failure. This might be regarded as justifiable on block oil trains and other tank cars of hazardous substances. Non tank cars carrying Ammonium Nitrate, preferably not mixed with oil tank cars, might be worth fitting.
But for general freight trains, unless all cars were fitted with derailment detectors, they will only work if a detector fitted car derails. A car with a detector could run for miles a few cars away from a derailed car without the actuator working.
Probably the biggest objection to ECP is the "electronic control" part. I would guess that the railroads view the weak link as the connections in the electrical control line through the train. With a ore or maybe a coal train, that only couples, uncouples once or twice a trip, its not that bad. But with other types of trains there will be more frequent coupling and uncoupling of the signal line.
Think about a hump yard. The electrical connection needs to stay reliable coupled but when the car is uncoupled, it has to part automatically without damage. The connection has to be reliable enough that if it is uncoupled and then sits in a track for 3 months, exposed, without coupling into another car, it can at a moments notice be used again.
Not saying it isn't possible, just saying I think that was percieved by the railroads as the weak spot in the system. Unit coal or ore trains might stay together (they don't always, only those on balloon loop loaders and unloaders. All the other trains (unit or otherwise) couple and uncouple frequently and the connection reliability is a concern.
Dave H. Painted side goes up. My website : wnbranch.com
Our community is FREE to join. To participate you must either login or register for an account.