Passenger Trains > Another Metro incident: Derailment Friday on Green lin

DC's troubled METRO system suffered another blow on Friday when a Green line train derailed in Prince George's County near West Hyattsville. Nobody was hurt and the three cars that derailed stayed upright. Police responded within 15 minutes and the train was evacuated. Nobody was hurt. Unconfirmed report suggests that a heat related kind may have been involved. Story in the local section of the Washington Post.

John Gezelius
Tustin, CA

You only caught a piece of it in your posting. Once the Green Line train had derailed (4 cars of it), they placed a heat speed restriction on the entire system. Metro-gridlock ensued.

Then, the far end of the Green Line had signal/switching problems and was reduced to a single track (I am surprised that they didn't, in the light of that situation, single track the whole system too.)

as one of my daughters friends wrote: I picked the right day to drive.

Sad!

More Metro follies! I drove Friday, and I'm glad I did.

I've posted before about Metro's complete lack of records regarding the temperature at which their CWR was laid. Not knowing the "neutral temperature" of the rail, they dare not weld in sticks of rail when they cut out defects, so the system (which was 100% CWR when built) is slowly turning into bolted rail. The bad news there is that their maintainers apparently don't know how to maintain rail joints. So the joints open, the bolts loosen, and pretty soon you've got a low spot that then turns into wide gauge. I've seen joint defects go uncorrected for months.

Last summmer, during a July heat wave, I worried every time my Yellow Line train crossed the bridge over the Potomac that we would derail on a sun kink.

Look at the bright side. MUCH less likely to get sun kinks on stick rail with loose joints than on CWR!

All these Metro problems would go away if we'd only give them a few billion to install constant tension third rail......

SZ

Steinzeit Wrote:
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> All these Metro problems would go away if we'd
> only give them a few billion to install constant
> tension third rail......

Well, a better use of the money would be to re-stress the running rails system wide (i.e., take track out of service, loosen all the fastenings, field weld all the bolted joints, vibrate the rails to re-distribute the stresses, and re-anchor the rail at a known temerature). And equipment does exist to heat or cool CWR to proper temperatures during this procedure if the weather won't cooperate.

illini73 Wrote:
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> And equipment does exist to heat or cool CWR to
> proper temperatures during this procedure if the
> weather won't cooperate.

But does it work in DC, or would they have to spend 3.2 billion on a research project to figure out if such a thing was feasible?

Today's story:

http://www.washingtonpost.com/local/trafficandcommuting/metro-says-heat-probable-cause-of-green-line-derailment/2012/07/07/gJQA1BcoUW_story.html?wpisrc=nl_headlines

NTSB will not investigate

John Gezelius
Tustin, CA

I think the techniques for de-stressing CWR are well understood in the railroad industry. What WMATA needs is a half dozen actual, competent degreed track engineers from a Class I railroad.

We de-stressed a lot of the CWR that was laid before David Gunn arrived in New York in 1983. The rail was laid completely without regard to proper neutral temperature. That wasn't a big problem in the subway, where temperatures don't vary too much, but was a big problem on places like the Brighton Line. So yes, we cut the rail with a saw, knocked off the anchors and let it run, then heated it to the "preferred rail laying temperature" and anchored it. It doesn't take a rocket scientist to figure this stuff out.