I've been watching all the oil trains go thru the "Diamonds" in Rochelle and noticed that all those trains of course are all tank cars but they all have one box car with roof vents either right after the engine consist or at the end of the train. What are those "special" box cars for?
A car containing extinguishers,oil soaking products along with shovels and other tools in case of a leak would make sense to me.Then I may be wrong......
"No soup for you!" - Yev Kassem (from Seinfeld)
There is nothing special about these cars. It is a regular car that is used to act as a buffer. Federal regulations say that you can't couple a car carrying hazardous materials directly to a locomotive. I am not sure how they pick cars to be used for this, but I assume they are empty, only weighted down so they don't derail.
The reason for this is safety. If the locomotive catches on fire, a string of tank cars filled with highly flammable fuel is the last thing you want near that locomotive. In a derailment, a ruptured tank car could spill fuel onto the hot prime mover.
mmm so why does this car appear at the end of the train sometimes?
A buffer for rear end collisions. It acts as a "cushion" to minimize damage to the tankers ahead.
Joe
darrel480 mmm so why does this car appear at the end of the train sometimes?
darrel480mmm so why does this car appear at the end of the train sometimes?
As noted above, hazmat cars cannot be coupled to locomotives, so if there are DPUs, there needs to be a car at the end. Also, at some unloading terminals, there is no loop, so the back becomes the front when empty. These cars are obsolete in other services, so they are quite cheap.
NorthWest darrel480 mmm so why does this car appear at the end of the train sometimes? Also, at some unloading terminals, there is no loop, so the back becomes the front when empty.
Also, at some unloading terminals, there is no loop, so the back becomes the front when empty.
darrel480 I've been watching all the oil trains go thru the "Diamonds" in Rochelle and noticed that all those trains of course are all tank cars but they all have one box car with roof vents either right after the engine consist or at the end of the train. What are those "special" box cars for?
Those BNSF 'Buffer' cars are retired Airslide hoppers that are filled to about 45 tons with either gravel or sand. The DM&E/CP likes to use old covered hoppers or box cars as the 'buffer'.
The reason for one at each end is due to a couple of possibilities:
DPU engines 'pushing'
Make switching ends easier
IIRC, the FRA has a directive out that each railroad is resposible for the buffer cars. DM&E has lots of problems with buffer cars being taken for other service, and there was no buffer car for the train when the DM&E went to pick up the returned train. The dedicated BNSF buffer cars fix that problem.
Jim
Modeling BNSF and Milwaukee Road in SW Wisconsin
When loaded, those trains had a DP engine, requiring a buffer on each end. (Buffer car requirements for most loaded hazmat tank cars are 5 when available with a minimum of at least 1 between the cars and engines. Empty cars only require 1 car.) Often when returning the trains are ran conventional, all power on the head end. Since the empty requirement is only for one, they don't have to switch the second one forward.
Jeff
JoeinPA A buffer for rear end collisions. It acts as a "cushion" to minimize damage to the tankers ahead. Joe darrel480 mmm so why does this car appear at the end of the train sometimes?
Out here, in the Great Western Wastes, 75% of these tank trains have a single locomotive on the tail end. My guess is the car was left in this position, because of this.
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Thank you all!
If you ever get close enough to read the "fine print" (i.e. the weight / length etc. lettering), you might see a stencil indicating the covered hopper is "FOR BUFFER SERVICE ONLY" or something similar...at least BNSF cars have it.
p.s. I believe the regulations against running a car with a flammable load right behind the engine goes back to steam days??
Just caught one on NS at CP Wyo the other day, all tank train, except for the covered hopper between the power and the first tank car. I'd expect they are loaded with sand, instead of a light car between the power and the loaded train.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
If the buffers are loaded with sand its for weight to keep the cars from jackknifing.
Dave H. Painted side goes up. My website : wnbranch.com
dehusman If the buffers are loaded with sand its for weight to keep the cars from jackknifing.
I been told by a NS conductor those cars are loaded for added braking and for DPUs or pushers..Also for runaround moves that is required for some customers.
Larry
Conductor.
Summerset Ry.
"Stay Alert, Don't get hurt Safety First!"
bruce22In the recent Trains Citirail video there is a tanker right behind the trailing loco, so I assume it is carrying a nonhazardous load ?
Yes, nonhazardous loads does not require a buffer car behind the engine.
IIRC the 6 car rule between a hazardous load and a occupied car or locomotive is still in effect for general freight train consists.
The hazardous placement rules are Federal law and are the same for every railroad operating in the US. They apply to any train of any type on any railroad, class 1 or shortline.
dehusman The hazardous placement rules are Federal law and are the same for every railroad operating in the US. They apply to any train of any type on any railroad, class 1 or shortline.
Dave,The railroads requested and received permission to use a single buffer car on oil tank trains not the required 6 as required by FRA rules.
Oil is considered a hazardous load.
BRAKIE dehusman The hazardous placement rules are Federal law and are the same for every railroad operating in the US. They apply to any train of any type on any railroad, class 1 or shortline. Dave,The railroads requested and received permission to use a single buffer car on oil tank trains not the required 6 as required by FRA rules. Oil is considered a hazardous load.
The rule is 5 buffer cars, train length permitting for loads. If train length does not permit, use all available buffer cars with a minimum of one being required. Empty cars/trains only require one buffer car.
If a loaded ethanol or oil train is operated in DP mode it needs at least one buffer car between the train and each set of engines. If for some reason (say for failure of the DP equipment) the rear engine is moved forward to the lead consist, that buffer car on the rear also has to be switched to the front end.
The reason being that in DP mode train length only permitted one buffer on each end. Once conventionalized, the train length now permits two buffer cars on the head end.
What Jeff said.
The rules require the engines or occupied car be the 6th car from the hazardous tank, length permitting. When the train length doesn't permit, there must be at least one car of cover. A unit hazmat train has no cover (train length doesn't permit 6 cars) so the minimum of one car has to be added. This applies to oils, trains and ethanol trains alike (as well as any other train with hazmat in it).
dehusman What Jeff said. The rules require the engines or occupied car be the 6th car from the hazardous tank, length permitting. When the train length doesn't permit, there must be at least one car of cover. A unit hazmat train has no cover (train length doesn't permit 6 cars) so the minimum of one car has to be added. This applies to oils, trains and ethanol trains alike (as well as any other train with hazmat in it).
Dave and Jeff,I believe that's what I said concerning oil tank trains..One buffer car.
BRAKIE dehusman What Jeff said. The rules require the engines or occupied car be the 6th car from the hazardous tank, length permitting. When the train length doesn't permit, there must be at least one car of cover. A unit hazmat train has no cover (train length doesn't permit 6 cars) so the minimum of one car has to be added. This applies to oils, trains and ethanol trains alike (as well as any other train with hazmat in it). Dave and Jeff,I believe that's what I said concerning oil tank trains..One buffer car.
But its not special exemption or permission or a certificate. Its the way it workd for ANY hazmat on ANY train. Same rules apply, its not a oil train or ethanol thing.
They certainly could, it wouldn't make any sense, but they could do it. Empty or loaded with something inert that wouldn't rot would be a better choice.