Heat related speed restriction and CWR management

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yarrow said:
when are heat restrictions imposed? are they a uniform speed if the temperature is above a certain point or do they very by track condition, host railroad and area?
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Each railroad has its own heat restriction agenda. FYI, there are also cold weather speed restrictions.
 
I wonder if putting that foam insulation around the track could reduce restrictions.
 
The MBTA Commuter Rail system is only affected by heat restrictions on the Framingham to Worcester tracks, which are owned by CSX.

Apparently the tracks that the MBTA owns and doesn't contract with Amtrak for the maintenance just don't have any heat restrictions.

(Amtrak also has heat restrictions on the NEC tracks that are shared with the MBTA, but those restrictions only reduce the speed to 80 MPH, and it apparently just so happens that the MBTA never exceeds 80 MPH anyway, although I believe the MBTA Commuter Rail equipment is capable of 88 MPH.)
 
For the Downeaster, there is a large sign at my station that says "When temperature is above 90 degrees, speeds are restricted to 40MPH. Expect delays".

Its rarely above 90 degrees, though I rarely in any hurry either.
 
what are Amtraks' plans late July 2011 for managing passenger and car safety during the current heat wave, in the NEC?
 
I traveled on #8 on Tuesday from St. Paul to Chicago, on CP rails. The defect detectors said the temperatures were between 95 and 100 F. There were no heat-related speed restrictions, though we didn't go above 80 mph, of course.
 
leah said:
what are Amtraks' plans late July 2011 for managing passenger and car safety during the current heat wave, in the NEC?
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[this is resurrecting a 3 year thread, but it is on topic]

The issues with the NEC for extreme heat are going to be with the catenary, more so than the tracks. Checking the Amtrak status map for the NEC as of 3:30 PM ET July 22, knock on wood, it is almost all green. Hardly any delays. Doing ok for 100+ degree temperatures over much of the NEC - so far. Maybe the work to rebuild and upgrade the power system is paying off, because I would expect with the A/C cranking on all the Amtrak and commuter trains, the power load is higher than normal. Now, of course, that I have posted this, the NEC will have a melt-down... :ph34r:

As for Amtrak's plans for passenger safety, don't know if they set out additional rescue locomotives for heat waves. Or they are just hoping that no more AEM-7 DC toasters, well, turn into flaming toasters.
 
Just got word that a MARC train is backing up to go around a disabled Amtrak train in the vicinity of BWI. A separate message mentioned single tracking, which is odd since there are 3 tracks through there.

Incidentally BWI just set a record high for today at 104, third highest temperature on record.
 
This should be interesting for Amtrak if the heat wave continues AND there is a partial FAA shutdown.
 
yarrow said:
when are heat restrictions imposed? are they a uniform speed if the temperature is above a certain point or do they very by track condition, host railroad and area?
Click to expand...
I have no idea of the American rules on heat, but here in Denmark track conditions is a factor.

The danger is what we here calls suncurves (again I have no clue of the English expression). They can happen when the rails expand in the heat and the pressure gets too big and suddenly the rails loose their grip in the ground and form bulge. If this happens when a train goes over at high speed the train will derail.

The risk is much bigger on poorly maintained tracks with old ties or too little foundatiion. Bane Danmark, the state company which owns the tracks here finally got funding to get rid of their maintenance backlog af few years ago after a nightmarish summer with trains running hours late and a rail that acutally broke under one train. At least on the main lines, they have said they don't expect any heat related delays this year (not that it would happen anyway as we seem to have gotten monsoon instead of summer here this year :( )

solkurve.jpg
 
It seems to me there was a major accident on the Auto Train due to heat restrictions not being imposed by CSX in Florida, years ago. Maybe that was not the ending cause, but I remember a major factor considered.
 
Oldsmoboi said:
This should be interesting for Amtrak if the heat wave continues AND there is a partial FAA shutdown.
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Any FAA shutdown won't affect essential air traffic control operations. If anything, it would increase air passenger traffic since some taxes won't be collected which will lower fares.
 
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afigg said:
The issues with the NEC for extreme heat are going to be with the catenary, more so than the tracks. Checking the Amtrak status map for the NEC as of 3:30 PM ET July 22, knock on wood, it is almost all green. Hardly any delays. Doing ok for 100+ degree temperatures over much of the NEC - so far. Maybe the work to rebuild and upgrade the power system is paying off, because I would expect with the A/C cranking on all the Amtrak and commuter trains, the power load is higher than normal. Now, of course, that I have posted this, the NEC will have a melt-down... :ph34r:
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Dang, should have NEVER that last sentence. The Amtrak status map for the NEC is now a lot of yellow and red tags! Now, there is reportedly a major service disruption between NYP and BOS. Oh dear. :help:
 
trainviews said:
I have no idea of the American rules on heat, but here in Denmark track conditions is a factor.
The danger is what we here calls suncurves (again I have no clue of the English expression). They can happen when the rails expand in the heat and the pressure gets too big and suddenly the rails loose their grip in the ground and form bulge. If this happens when a train goes over at high speed the train will derail.
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The US term is normally sun kink or buckling. Track condition is a big factor.

When rail is to be welded up, it is stretched to be a zero stress at a specific temperature. The number is not the same everywhere because the temperature range the rail experiences is not the same everywhere. For a country like Denmark, it would be quite reasonable to set one temperature as a national standard. For the US, obviously not.

The temperature of concern is the temperature of the RAIL, not the temeprature of the air. The rail can be up to 30 degrees (Fahrenheit) or more higher than the air temperature due to heating from the sun.

Traditionally in building anything with steel you try to make sure you allow for expansion and contraction due to temperature changes. With continuously welded rail, instead you consider the build up of forces in the steel. That is when it gets cold, the steel wants to contract but cannot, so tensile forces build up in the rail. When it gets hot, it wants to expand but cannot, so compressive forces build up in the rail. If the tensile forces get too high, the rail breaks apart. It the compressive forces get too high, the rail kicks out sideways. When laying continously welded rail, the objective is to set it so that it has no stress, either tensile or compressive, at a temperature which ensures that maximum temperature it will get to will not cause it to kick out into a sun kink, nor so low that it will result in a pull apart. The important issue is not absolute rail temperature, but the difference between the rail temperature and the temperature at which it will have no stress, called the zero stress temperature

The zero stress temperature formula used in the US is tilted toward keeping the rail in tension most of the time, which is the best way. It is easier to keep something long and flexible straight when it is being pulled instead of pushed. It is: Add 2 times the high temperature to the low temperature, divide the sum by three, add a constant number, usually in the range of 15 to 25 degrees fahrenheit.

Can write it as (2H+L)/3+C

The answer is usually rounded off to the nearest 5 degrees. Also, usually quite a few points are checked over the area of concern and an average value covering a fairly large geographic area applied. Commonly, values of 90 egrees or higher or found in the US.

Another reason higher is better: A pull apart in signaled track is detected by the signal system, so it tells you it has happened. A sun kink does not tell the signal system anything.
 
zepherdude said:
It seems to me there was a major accident on the Auto Train due to heat restrictions not being imposed by CSX in Florida, years ago. Maybe that was not the ending cause, but I remember a major factor considered.
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While there was indeed a major derailment of the Auto Train that killed several people and badly damaged many cars, it wasn't because CSX had failed to impose heat restrictions. It was because CSX had improperly handled the track IIRC. While I'm not an expert in this area, a simplification of things goes like this. When you go to weld the rail, you first heat it to what's called the median temperature. This puts the rail in the right position for contraction and expansion, kind of s sweet spot if you will. Then when the rail is at that point, you weld the two ends together.

The crew in the field failed to properly heat the rails to the correct temp before welding. They further made things worse by not properly dealing with the ballast. A heat wave hit and right after a southbound coal train passed (the crew reported a rough ride), the rail moved under the immense pressure. Shortly after along came Amtrak and on the ground it went.

It was after that accident, and another with the Capitol Limited where the CSX crews forgot to impose a slow order after doing track work, that CSX decided to punish Amtrak for falling off its rails by imposing a slow order during heat waves now. Mind you freight trains hauling things like chlorine gas that can kill many more people continue to run at normal speed.
 
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AlanB said:
zepherdude said:
It seems to me there was a major accident on the Auto Train due to heat restrictions not being imposed by CSX in Florida, years ago. Maybe that was not the ending cause, but I remember a major factor considered.
Click to expand...
While there was indeed a major derailment of the Auto Train that killed several people and badly damaged many cars, it wasn't because CSX had failed to impose heat restrictions. It was because CSX had improperly handled the track IIRC. While I'm not an expert in this area, a simplification of things goes like this. When you go to weld the rail, you first heat it to what's called the median temperature. This puts the rail in the right position for contraction and expansion, kind of s sweet spot if you will. Then when the rail is at that point, you weld the two ends together.

The crew in the field failed to properly heat the rails to the correct temp before welding. They further made things worse by not properly dealing with the ballast. A heat wave hit and right after a southbound coal train passed (the crew reported a rough ride), the rail moved under the immense pressure. Shortly after along came Amtrak and on the ground it went.

It was after that accident, and another with the Capitol Limited where the CSX crews forgot to impose a slow order after doing track work, that CSX decided to punish Amtrak for falling off its rails by imposing a slow order during heat waves now. Mind you freight trains hauling things like chlorine gas that can kill many more people continue to run at normal speed.
Click to expand...
Amtrak Crews have mentioned that CSX hates Amtrak, hate is a strong word, but that word was used. It is my understanding CSX did not want the 1st leg of the Sunset Limited to resume as it is on their tracks.
 
zepherdude said:
AlanB said:
zepherdude said:
It seems to me there was a major accident on the Auto Train due to heat restrictions not being imposed by CSX in Florida, years ago. Maybe that was not the ending cause, but I remember a major factor considered.
Click to expand...
While there was indeed a major derailment of the Auto Train that killed several people and badly damaged many cars, it wasn't because CSX had failed to impose heat restrictions. It was because CSX had improperly handled the track IIRC. While I'm not an expert in this area, a simplification of things goes like this. When you go to weld the rail, you first heat it to what's called the median temperature. This puts the rail in the right position for contraction and expansion, kind of s sweet spot if you will. Then when the rail is at that point, you weld the two ends together.

The crew in the field failed to properly heat the rails to the correct temp before welding. They further made things worse by not properly dealing with the ballast. A heat wave hit and right after a southbound coal train passed (the crew reported a rough ride), the rail moved under the immense pressure. Shortly after along came Amtrak and on the ground it went.

It was after that accident, and another with the Capitol Limited where the CSX crews forgot to impose a slow order after doing track work, that CSX decided to punish Amtrak for falling off its rails by imposing a slow order during heat waves now. Mind you freight trains hauling things like chlorine gas that can kill many more people continue to run at normal speed.
Click to expand...
Amtrak Crews have mentioned that CSX hates Amtrak, hate is a strong word, but that word was used. It is my understanding CSX did not want the 1st leg of the Sunset Limited to resume as it is on their tracks.
Click to expand...
CSX gave Amtrak permission to restart service 6 months after Katrina. The fact that the Sunset east isn't running is all on Amtrak. CSX has nothing to do with it.

As for hating Amtrak, if you mean track crews then I can't speak to that. But the operating crews of trains never seem to have any problems with Amtrak, always very friendly on the radio and checking our train for problems which the Amtrak crews also do for CSX.
 
Fascinating descriptions by GeorgeHarris & AlanB re the steel/rails/heat/cold for the clueless among us (from the topic headline, I thought the subject was going to be about train air-conditioning or heating systems, lol).

But now I'm curious: My grandfather was a RR man from the 1920s thru retirement in the 1970s (except for 4 years overseas in the service for WW2). All I know is that he was a "Railroad Inspector," first for the RR company(ies) themselves, but later as a "Railroad Inspector" for the Govt. After reading the heat/cold descriptions, I'm now wondering if that is what a "Railroad Inspector" does, is go along tracks inspecting them for safety(?) -- (I previously assumed he inspected engines & such.) "Pop" worked beginning in Wilmington, NC; later transferred to JAX; later to Rocky Mount, NC; later to Columbus, OH; later to Birmingham, AL; then retired back in Wilmington, died in 1977. (My grandmother worked for the RR during the 1920's in Wilmington, not sure doing what, but that is how Pop & she met. Pop's transfer to JAX in the late 1940's is how their daughter/my mother met my Dad. You could say I'm on this earth thanks to the RR. As little kids we rode the trains from JAX to NC to visit the grandparents, with aluminum-foil-lined shoe boxes full of fried chicken prepared beforehand by Mom. :)
 
PS: Meant to add: Glad to also learn the reason for no JAX to NOL service! Bummer... have to go to DC & back down to get from FLA out West.
 
Crescent canceled past Atlanta due to heat (?) I have a friend aboard the Crescent tonight. They've been told the rain is terminating in Atlanta and they will be bussed to New Orleans. The reason given is that it's due to a heat advisory in the south. What would the issue be? It doesn't make sense to me that Amtrak can't run a train in the summer heat in the south.
 

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