Posted on 07/09/2013 4:43:49 AM PDT by thackney
I was wondering the same thing. Also one article mentions an explosion, but I don't know if the author meant an "explosion" from collision noise or a 2,000 degree over pressure explosion.
Very Interesting. Keep me posted please.
If this was deliberate sabotage they are responsible for multiple murders.
This should give even more importance to the Keystone pipeline.
Perhaps a spring would work better.
No matter the brakes or whatever, a train should never be left alone. IMO.
The cost of one man left with the train is nothing compared to the damage done here.
Westinghouse's 1869 version, the straight or direct air brake, used air hoses to connect the cars. When the engineer turned on the brakes, air pressure turned the brakes on in each car of the train. Of course, if the hoses leaked or disconnected, the train lost braking power.
With air brake 2.0, Westinghouse turned things around. Air pressure kept the brakes off. The engineer reduced pressure to put the brakes on. This built-in safeguard meant a loss of pressure would stop the train automatically. That applied to leakage and to the situation where cars came unhitched: Loose cars would brake to a stop. The system went into use in 1872 on the Pennsylvania Railroad.
http://www.wired.com/science/discoveries/news/2008/03/dayintech_0305
FRED lets engineers know about pressure conditions at the end of the train nowadays (it used to be the guy who road in the caboose).
FRED stands for flashing rear end device, and FRED has a radio transmitter and regularly reports conditions on the air line.
I had wondered how the crude got caught on fire.
A heavy train will roll even if a few cars have hand brakes on.
In a word, no.
https://en.wikipedia.org/wiki/Railway_air_brake
"An air brake is a conveyance braking system actuated by compressed air. Modern trains rely upon a fail-safe air brake system that is based upon a design patented by George Westinghouse on March 5, 1868. The Westinghouse Air Brake Company (WABCO) was subsequently organized to manufacture and sell Westinghouse's invention. In various forms, it has been nearly universally adopted."
While billed as "fail safe" the Westinghouse air brake system can and does sometimes fail, leaving rheostatic brakes (which don't work w/out engines), manual brakes (which were engaged but on only a few cars), and emergency brakes (which are dependent on air pressure which fell to zero when the engine was shut down). Unlike truck brakes which apply with spring pressure and release when pressure is applied, train air brakes are applied and released by raising and lowering the pressure in a line that runs the length of the train. The individual cars apply their brakes using an air reservoir on each car in response to changes in the "train line" pressure.
Regards,
GtG
Doesn’t sound too fail-safe to me.
I really do believe no train should be left running with no one in it.
All trains have a device on the last car that monitors air pressure and is in radio contact with the head end. It attaches to the air line and is mounted on the knuckle.
It’s called a FRED Unit, which stands for friendly rear-end device. (Sounds kind of gay.)
Engineers (not train drivers) have a saying: Every time that you make something "fool proof", God makes a more talented fool!
I really do believe no train should be left running with no one in it.
It happens more often then you might suspect, 99.9% of the time it doesn't matter. It's that 0.1% that bites. There are times when it's unavoidable, I would think it a better policy to chock the wheels just to be sure. Trains have four braking systems and that should suffice. This time it wasn't enough to quell the perfect storm. Very sad...
Regards,
GtG
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