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US, Canada: DOT-111s gone in 5 years
What about the shelf couplers that keep the cars from uncoupling in a derailment. That also keeps the air hoses connected thereby preventing an emergency brake application and allowing more cars to derail and pile up in an accordion arrangement. Is the benefit with the risk?
Will there even be crude-by-rail in five years?
I am assuming the requirement for ECP brakes will only apply to unit trains. The article is not clear. Enough locomotives from the various railroads will also have to be specially equipped with controls. Similarly a fleet of assigned buffer cars will also need to be ECP equipped. Those are not insuperable problems but will lead to inefficiencies in operation for marginal safety benefit.
To comment on WM’s post, the shelf couplers do serve a useful purpose. It used to be far more common to have the coupler of a detached car punching the tank of a neighbor as they pile up in a derailment. It was all too easy for the cars to separate. The accordion arrangement dissipates the energy in less destructive ways, although of course at higher speeds bad things will still happen. Once a derailment occurs the train will break in two and experience an emergency brake application with either type of coupler. Another rare benefit of the shelf coupler is where it supports the end of a car missing a truck or wheelset and actually prevents a derailment.
How do electric brakes work? I’d presume or hope like any electric life/safety system in a building, fail safe. Applied voltage applies EM force to a solenoid to hold the calipers open; loss of power means the springs forces the brakes to actuate. Seems pretty basic to me, anyhow.
Mr. Anderson, as I’m sure you already know standard air train brakes apply with a reduction in brake pipe pressure and vice versa. In such system the last car on the train is the last to apply/release due to the time it takes for the pressure to decrease/increase. With EP brakes the signal to apply is simultaneous to the whole train. A wired or wireless signal opens a vent valve on each car at the same time to reduce pressure and cause an application thus reducing braking times. On a loss of power the cars revert to the standard mechanical system.
Very intricate , these electronically assisted brakes Q & A’s are.
Having read about the electrically controlled passenger train’s brakes of the 1930’s, having operated and fumbled the ball with the electricity controlled brake- equipped passenger cars and locomotives of the 1970’s Amtrak fleet and having run and taught crews of the mid-70’s RCU’s, primitve parent of today’s DPU’s, and read, short of formal research, of the current Electronic Air Brake scheme and DPU’s.,
I agree with the AAR that fully equipped hazmat trains would be overkill.
A more than adequate improvement in train brake operation speed would be cutting into those trains a DPU locomotive 2/3’s of the train’s length behind the road locomotive.
Brake pipe pressure reduces from thirds of the train, instead of all from head end BP. reduction.
Shelf couplers…keep 'em.
Electronic brakes would shorten stopping distances and may reduce in train forces during braking so it is conceivable that they could prevent a future accident. However, I don’t know if they would have prevented any of the recent accidents that led to these regulations.
With an eot you can already apply brakes from the rear first
DO from Indiana,
You’re right,but the application is intended to complete a train brake application interrupted by a closed midtrain angle cock; the only available application is at the emergency rate., not desirable unless you absolutely have to use it.
With all the commentary about the added weight of head shields, jacketed tanks, etc,.why not require the cars to have frames like they used to? They could be designed to protect the valves on the bottom of the tank by surrounding it. It seems like frames disappeared from tank cars just before a rash of accidents in the late '60s and early 70s in which cars of LPG caught fire and exploded, sending large pieces of the tanks (propelled by the burning contents) flying a considerable distance from the derailment site.
How does each car get electric power, I don’t recall seeing electrical lines coming from the engines. Would each car have a battery to power its electronic brakes on each car. Any electronic device needs a electric power to function.
How would a Telly receive air if an angle cock was closed. You would have drug those cars with brakes on.
“The truth is” after these changes are implemented shipping these materials by rail becomes more expensive, so more of it is diverted to highways, creating more hazards on the highways. Did more than 99.9 percent of these materials shipped on roads reach their destinations safely? Mr Secretary please redirect your eye towards perfection on our roads that killed more then 30,000 people and maimed many times that number last year.