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Oil Train Explosion Triggers Evacuation In North Dakota
Hugh Pickens DOT Com writes "The LA Times reports that the small town of Casselton, North Dakota dodged a bullet after being partially evacuated when a train carrying crude oil collided with another train, setting off a large fire and explosions. Officials received a report at 2:12 p.m. of a train derailing about a mile west of Casselton, a city of 2,432 people about 20 miles west of Fargo. At some point, another train collided with the derailed train, belonging to the BNSF Railway, carrying more than 100 cars loaded with crude oil. The explosions and fire erupted after cars from a grain train struck some of the oil tank cars. 'A fire ensued, and quickly a number of the cars became engulfed,' said Sgt. Tara Morris of the Cass County Sheriff's Office, adding that firefighters had managed to detach 50 of the 104 cars but had to leave the rest. This was the fourth serious accident involving trains hauling crude in North America this year. In July, an unattended train with 72 tank cars carrying crude oil from North Dakota's Bakken shale fields rolled downhill and set off a major explosion in Lac-Megantic, Quebec, killing 47 people. The accidents have put a spotlight on the growing reliance on rail to move surging oil production from new fields in Texas, North Dakota and Colorado. U.S. railroads are moving 25 times more crude than they did in 2008, often in trains with more than 100 tank cars that each carry 30,000 gallons. Though railroads have sharply improved their safety in recent years, moving oil on tank cars is still only about half as safe as in pipelines, according to Eric Smith, associate director of the Tulane University Energy Institute. 'You can make the argument that the pipeline fights have forced the industry to revert to rail that is less safe,' says Smith. One problem is that the trains go through small towns with volunteer fire departments, not well schooled in handling a derailment and explosion. Casselton Mayor Ed McConnell says it is time to 'have a conversation' with federal lawmakers about the dangers of transporting oil by rail. 'There have been numerous derailments in this area,' says McConnell. 'It's almost gotten to the point that it looks like not if we're going to have an accident, it's when.'"
Because pipes - http://en.wikipedia.org/wiki/Yellowstone_River#2011_oil_spill
are always - http://en.wikipedia.org/wiki/Kalamazoo_River_oil_spill
safe - http://en.wikipedia.org/wiki/2013_Mayflower_oil_spill
Back in the late 70's I used to work for the only company in Canada that manufactured very large ball valves for pipelines. We are talking in excess of 10 ton's with 42" flanges. We supplied Trans Canada Pipelines, Foothills, etc. I designed the pressure testing rig and tank for these very large units.
Know what the biggest problem was/is with pipelines? Materials used in manufacturing.
"Sour" gas vs "Sweet" gas valves (and the pipeline itself) are made of completely different materials. An "O" ring housing for example may be made from Titanium for a corrosive sour gas and Stainless Steel for sweet non corrosive gas.
More than once, on smaller valves (gate or ball, I forget now) we had to investigate why a valve failed and it was always the incorrect material. Some worker swapped a part behind QC's back thinking "no big deal, they look the same".
Perhaps traceability and manufacturing has improved (I would hope so) by now though.
On an interesting side note, the big guy's were tested at 20,000kpa, or about 2900psi. The rumor went that if there were ever a pinhole leak in one of the 3" deep welds, or porosity in the casting and you walked through it without seeing it, it would cut you in half.
Nothing is perfectly safe, but I do think a pipeline is "safer" than rail transport.