I was watching a DM&IR YouTube video and was wondering why they do not use larger hoppers? Is a weight issue or radius curves?
Thanks for any input.
frank train
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Weight. Iron ore is considerably heavier than coal or aggregates.
Rusty
Definitely weight, as Rusty stated. For example, those little short "ore jenny" cars are about 100 tons EACH, when loaded with ore or Taconite. Compare that to a "steam era" 34 foot 2-bay hopper at only 55 tons, or the large 3-bay coal hoppers at only 70 tons.
Thanks for your fast replies. I never would have figured that.
Frank
Another clue is the occasional overhead photo of a train hauling ore in ordinary hopper cars. The top of each load is well below the top of the car. That keeps the weight of the ore within the load limit of each car.
Previous posters have bit the nail on the head. Iron ore is so heavy it always "Loads Out." The terms used in transportation this context are:
Loads Out - meaning the load will reach the weight capacity of the car before the car is full. Iron ore in standard hoppers is a great example. The hopper will be only about 1/3 "full" but will be at its weight capacity. Paper, certain other ores and some kinds of steel will also load out.
Cubes Out - means the load will fill the car before reaching the weight capacity of the car. Think a box car full of ping-pong balls.
The "small" hoppers use by the DM&IR are not actually called hoppers. They are properly called "ore cars" and are specifically built to be able to be loaded to their cubic capacity while still coming it at their weight limit. No sense building (and buying) more car than you need.
The PRR loaded coal hopper cars at each end to place the weight directly over the axles.
A method Seen here in the attached video
