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CSX explains slower train speeds in heat or heavy rain

Why do trains on MARC's Camden and Brunswick Lines sometimes run slowly? One reason is the weather: CSX, which owns the tracks, orders MARC trains to slow down for safety when it's hot or very rainy.


Photo by Don Shall on Flickr.

That's what CSX Vice President for Passenger Operations Jay Westbrook told the MARC Riders Advisory Council last week. High temperatures can make the rails buckle. If a train goes over a buckle or sun kink, the train may derail, as Amtrak's Capitol Limited did near Kensington in 2002. Meanwhile, a lot of rain can wash out the track bed, causing the tracks to collapse.

Heat is a problem because modern railroads use continuous welded rail, rather than jointed track. Continuous welded rail is sections of rail that are 1/4-mile long, with the ends welded to the next section of rail. Unlike jointed track, there are no gaps between the sections of rail to accommodate expansion when the rail gets hot. Instead, the rail spikes, tie plates, rail anchors, and track ballast are supposed to keep the rail in place.

The Federal Railroad Adminstration requires track owners to have a plan for continuous welded rail. The plan must include procedures governing train speed on continuous welded rail track when "the difference between the average rail temperature and the average rail neutral temperature is in a range that causes buckling-prone conditions to be present at a specific location."

CSX owns the tracks on MARC's Brunswick and Camden Lines. CSX issues a heat order for operations between 1 pm and 7 pm if the predicted high temperature for the day is 90 degrees or higher, or if there is a large predicted change in temperature (e.g., 25 degrees or more), especially if the predicted high temperature is higher than 85 degrees. Large predicted changes in temperature are usually the reason for heat orders in the fall or spring.

If CSX issues a heat order, passenger trains must go 20 miles per hour below the maximum authorized speed, but not less than 40 miles per hour. Freight trains must go at least 10 miles per hour below the speed limit, but not less than 30 miles per hour. On the Brunswick and Camden Line tracks, under normal operations, the maximum authorized speed is 79 miles per hour for passenger trains and 60 miles per hour for freight trains.

Thus, for example, the usual maximum speed for a passenger train with a heat order would be 59 miles per hour. However, if the maximum authorized speed for a particular section of track were 45 miles per hour, then under a heat order, the passenger train would go 40 miles per hour, not 25 miles per hour.

The slower speeds not only help the engineers look out for buckles but also prevent buckling in the first place, because a slower train puts less stress on the track, Westbrook said.

For rain, said Westbrook, CSX currently uses Accuweather's Skyguard service, which provides weather information for specific locations. Skyguard issues flash flood warnings based on recent rainfall, the predicted hourly rainfall rate (more than 1 inch per hour or 3 inches per 3 hours), the total predicted rainfall, and local conditions, such as elevation and soil. Under flash flood warnings, the maximum speed is 40 miles per hour.

Miriam Schoenbaum lives in Montgomery County's Agricultural Reserve. She serves on the MARC Riders' Advisory Council and is a member of the Action Committee for Transit

Comments

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Worth nothing that CSX also operates the Brunswick and Camden lines under contract.

by Tim on Jul 23, 2013 1:59 pm • linkreport

@Tim:
No, they do not. As of about 3 weeks ago, Bombardier has taken over the contract. CSX no longer operates regularly scheduled passenger service anywhere.

by Matt Johnson on Jul 23, 2013 2:05 pm • linkreport

Welcome to the 21st century.

by Jasper on Jul 23, 2013 2:07 pm • linkreport

How does Amtrak deal with heat buckling issues on the NEC without imposing these sort of restrictions?

by andrew on Jul 23, 2013 2:08 pm • linkreport

This also happens on VRE's Fredericksburg Line

However, Norfolk Southern who owns the tracks on the Manassas Line doesn't issue heat restrictions

by Davin Peterson on Jul 23, 2013 2:10 pm • linkreport

@andrew: think it has something to do with the concrete ties, instead of the conventional wooden ones on brunswick/camden. guess the rails are really anchored to the concrete ties and tend not to kink, as is my understanding

by JessMan on Jul 23, 2013 2:13 pm • linkreport

@Matt Johnson, what's the benefit of continuous welded rail on the Metropolitan Branch (or most freight mainlines)? It's not like anyone would ever want to run particularly fast trains there.

by Steve S. on Jul 23, 2013 2:18 pm • linkreport

@Steve S.
Less wear and tear on the rollingstock. Less maintenance needed on the rails. Less friction, so energy savings.

by Matt Johnson on Jul 23, 2013 2:22 pm • linkreport

@Steve S
Continuous welded rail was first used by the freight railroads. The primary reason for using it to eliminate the need to inspect and maintain the joints.

by Sand Box John on Jul 23, 2013 2:26 pm • linkreport

Over 90% of american rail miles are wood, unlike in Asia and Europe where the majority are concrete. It costs more to build a rail bed for concrete ties and the ties cost more and are heavier so more difficult to install but they last longer, are safer, and are less susceptible to washing out or warping in heat.

Of course our national infrastructure is decades out of date.

by Richard B on Jul 23, 2013 2:31 pm • linkreport

@andrew -- the Northeast Corridor is a different class of track.

If you're interested, you can find the FRA requirements for the different classes of track here:

http://www.gpo.gov/fdsys/pkg/CFR-2011-title49-vol4/pdf/CFR-2011-title49-vol4-part213.pdf

by Miriam on Jul 23, 2013 2:48 pm • linkreport

"The plan must include procedures governing train speed on continuous welded rail track when "the difference between the average rail temperature and the average rail neutral temperature is in a range that causes buckling-prone conditions to be present at a specific location."

I am guessing that this outdated infrastructure does not take climate change much into account.

by spookiness on Jul 23, 2013 2:49 pm • linkreport

How does High-speed Rail deal with this?

by xmal on Jul 23, 2013 2:58 pm • linkreport

How does High-speed Rail deal with this?
High speed rail uses concrete ties or more often ballast-less track beds. Essentially mounting the rails directly on a huge slab of concrete strong enough to resist and thermal deformation.

by Richard B on Jul 23, 2013 3:24 pm • linkreport

Heat restrictions do occur on the Marc Penn Line from time to time. Not sure whether the concern is the rails, the pwoer wires, or both.

by JimT on Jul 23, 2013 4:13 pm • linkreport

@JimT

The Penn line heat restrictions come from Amtrak and are over concerns that the overhead catenary wires will droop in the heat.

by fj on Jul 23, 2013 4:18 pm • linkreport

Amtrak has temperature sensors attached to the rails on the NEC and will impose heat restrictions when the rails get too hot. Heat restrictions for the old style hanging catenary on the southern half of the NEC are more common. I think Amtrak imposed heat restrictions for both track and catenary late last week with all the trains running late during the afternoon.

by AlanF on Jul 23, 2013 4:49 pm • linkreport

Amtrak has temperature sensors attached to the rails on the NEC and will impose heat restrictions when the rails get too hot. Heat restrictions for the old style hanging catenary on the southern half of the NEC are more common. I think Amtrak imposed heat restrictions for both track and catenary late last week with all the trains running late during the afternoon.

This may be the case, the the speed restrictions on the NE(Penn) line are normally much higher than on the Camden and Brunswick lines. Usually the Penn line MARC doesnt suffer to much, because it usually cannot get up to the top speed anyway because it has to stop so much. What slows it down is if the Amtrak/Accela's get really backed up as they have priority.

by Richard B on Jul 23, 2013 5:00 pm • linkreport

Trains in Japan don't slow on hot days.

by Steve on Jul 23, 2013 7:39 pm • linkreport

Trains in Japan don't slow on hot days. Yes, they invested in more expensive but easier to maintain concrete ties for all their rail lines and ballastless track for all their HSR lines. Heat is not a problem.

by Richard B on Jul 24, 2013 9:13 am • linkreport

"I am guessing that this outdated infrastructure does not take climate change much into account."

Actually, Continously Welded rail is the industry standard for higher-speed operations. You actually can't go faster than 60 MPH over jointed rail track, and even if you did, the ride quality would be horrendous (bumpy does not do justice to it).

by Aaron Z. on Jul 24, 2013 11:59 am • linkreport

Correction on my own post: Jointed rail can be used in anything up to Class 5 track; while ride quality will generally deteriorate (that part I do know is true) you can at least in theory run passenger trains over jointed rail at 90 MPH (again, you'd probably get a very bumpy ride).

by Aaron Z. on Jul 24, 2013 12:09 pm • linkreport

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