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The Dangers of Train Yards, Through the Eyes of Railroad Employees

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Re: The Dangers of Train Yards, Through the Eyes of Railroad Employees

#51

Post by TylerE »

Doctor_Fegg wrote: post #38
TylerE wrote: post #31

Earlier quoted context omitted.

The locomotives, not all the rolling stock. I'm not saying it wouldn't be hard/expensive, but it seems better to spend money on things that will be useful for decades rather than stopgaps that just kick the can a little further up the road.

Most British passenger trains are multiple units (and most British trains are passenger trains), so there's effectively little distinction between locomotive and rolling stock.

You have a cab at both ends. In between are just slave units. No cabs, even if they have motors.

Re: The Dangers of Train Yards, Through the Eyes of Railroad Employees

#52

Post by AnimalMuppet »

adrianN wrote: post #43
Retric wrote: post #39

Earlier quoted context omitted.

Longest trains are under five miles so you could use that or whatever the limit for that line is as a safe baseline. Unless you're worried about trains separating.

You are worried about trains separating.

Even more if you have distributed power. A train can separate, and both halves can keep moving.

Re: The Dangers of Train Yards, Through the Eyes of Railroad Employees

#53

Post by sandworm101 »

21 wrote: post #37
adrianN wrote: post #28

Earlier quoted context omitted.

It takes a while until the brakes in the last car start braking because the pressure doesn't drop everywhere simultaneously.

Why not also use an electric cable? Sounds like a problem, since the first car will have to "resist" the rest of the train.

Electricity wouldn't scale. Solenoids on each brake system would take current. Adding new cars would increase the load on whatever is providing that current. To ensure that cars could be swapped in and out, the cables on all cars would have to be large enough to provide current for even the longest train.

Air brakes, once pressurized, don't take much to maintain. Relatively small pipes work on even very long trains. You can add cars all day without increasing the steady load on the compressor. A longer train will take longer to pressurize, but once there it would not need the compressor to run constantly. Air is also not as dangerous as running large electrical cables the length of a train.

Re: The Dangers of Train Yards, Through the Eyes of Railroad Employees

#54

Post by 21 »

sandworm101 wrote: post #53
21 wrote: post #37

Earlier quoted context omitted.

Why not also use an electric cable? Sounds like a problem, since the first car will have to "resist" the rest of the train.

Electricity wouldn't scale. Solenoids on each brake system would take current. Adding new cars would increase the load on whatever is providing that current. To ensure that cars could be swapped in and out, the cables on all cars would have to be large enough to provide current for even the longest train. Air brakes, once pressurized, don't take much to maintain. Relatively small pipes work on even very long trains.…

I meant electricity just for the triggering, not for the action. A small electric signal could for example open a valve in the air tube. Thus all cars would break at the same time.

Re: The Dangers of Train Yards, Through the Eyes of Railroad Employees

#55

Post by giarc »

mturmon wrote: post #22
dmckeon wrote: post #15

Not to make light of railyard hazards, but: > the union had more than 30 railroad employees take photos of their workplace in an effort to demonstrate the hazards firemen could help navigate around. suggests that the presumably union workers may have tended to choose to take photos of the more (or most) dangerous locations. For a company perspective from the 1940s, see ""Why Risk Your Life?" -- 1940s Railroad Safety…

...choose to take photos of the more (or most) dangerous locations... That would be where the accidents happen, right? Thus the photos are taken there.

I think OP is just commenting on how union workers would be a biased source on just how common unsafe designs are.

Re: The Dangers of Train Yards, Through the Eyes of Railroad Employees

#56

Post by giarc »

The title (Dangers of Train Yards) reminds me of a story told by an acquaintance who worked in a yard many years ago. He said they would fuel the engines by inserting a hose and letting it run. It would take a long time to fill the tanks and so they would walk off to complete other tasks. They would return and more often than not, the tank would just be overflowing diesel into the ground. He didn't think they would ever be able to remediate rail yards because of the contamination.

Re: The Dangers of Train Yards, Through the Eyes of Railroad Employees

#57

Post by jacquesm »

pixl97 wrote: post #24
jacquesm wrote: post #7

Earlier quoted context omitted.

And excavator and backhoe workers too as well as heavy presses.

Eh, /r/watchpeopledie has taught me that heavy equipment will murder you in a violent fashion if you don't respect it.

I got within a hair. Stupid, stupid, stupid. In a nutshell: I was working with a backhoe that was older than I was, early 60's model and a hydraulic line developed a very small puncture, enough that I could see the line start to sweat. Instead of backing off I got closer to see if the drop I saw on the line was really oil or maybe water. Fortunately before I could reach for it but after I got way too close the line exploded. Blinded me for about 15 minutes completely, the oil got infused into the fabric of my sweater so deep that even 12 years later (yes, I hate throwing stuff away) you can still clearly see where it hit. And that was just a hydraulic line bursting, we're not into accidents with buckets and blades territory.

Re: The Dangers of Train Yards, Through the Eyes of Railroad Employees

#58

Post by btilly »

dredmorbius wrote: post #11
ChuckMcM wrote: post #9

I got a chance to drive a couple of different engines at the Plumas rail museum. And one of the things that does is help you internalize the amazing amount of mass and momentum a train carries around all the time. The engineer who was with us spoke of freight trains that were a hundred cars of iron ore that, even though they were travelling at only 5mph would take nearly 1000' to bring to an "emergency" stop. While I…

My experience is largely with bicycles (you're very aware of the energy input/output), automobiles, and boats, but thinking of moving vehicles as momentum systems , to which energy can be added or removed, is useful. On a bike, you maintain a steady speed by matching drag losses with the energy you're putting into the pedals. Braking and other actions cost you energy you've put in. For automobiles and trucks, added m…

On a bike, you maintain a steady speed by matching drag losses with the energy you're putting into the pedals. Braking and other actions cost you energy you've put in.

Which is exactly why bicycles are so fond of rolling through stop signs. When you're riding one, it is obvious to you that going from 20 mph down to 10, then back up to 20 is reasonably safe and only takes half the effort as going from 20 mph down to 0 and then back up to 20.

Re: The Dangers of Train Yards, Through the Eyes of Railroad Employees

#59

Post by extrapickles »

21 wrote: post #54
sandworm101 wrote: post #53

Earlier quoted context omitted.

Electricity wouldn't scale. Solenoids on each brake system would take current. Adding new cars would increase the load on whatever is providing that current. To ensure that cars could be swapped in and out, the cables on all cars would have to be large enough to provide current for even the longest train. Air brakes, once pressurized, don't take much to maintain. Relatively small pipes work on even very long trains.…

I meant electricity just for the triggering, not for the action. A small electric signal could for example open a valve in the air tube. Thus all cars would break at the same time.

Some trains already to this, where they put in electronic valves in the air lines for in car. Basically, the electronic valve controls if the existing brake is vented or connected to the central air line. This still allows for the fail-safe behavior of being able to brake the train from the central air line by venting it.

This lets them start easier/quicker from a stop, as they don't have to re-air the entire train and less wear on the brakes of the trains in the front of the train as all the cars start braking at the same time. This is particularly useful for trains that have to start on a hill as taking minutes for your brakes to fully turn off can complicate things.

Re: The Dangers of Train Yards, Through the Eyes of Railroad Employees

#60

Post by ythn »

kposehn wrote: post #20
sandworm101 wrote: post #13

Earlier quoted context omitted.

>> 5mph would take nearly 1000' to bring to an "emergency" stop. That seems far fetched. 1000' is a long way at 5mph. The number of engines doesn't matter. Each car has its own brakes in an emergency. Cut pressure in the line and every car will brake itself. Perhaps they meant situations involving hills, not uncommon for ore trains heading from mines.

A 30,000 ton ore train in Brazil will take about that long to stop, due to the nature of that weight strung out over 2.5 miles of distance. That said, I think an emergency stop (air loss) would stop it faster.

> A 30,000 ton ore train in Brazil will take about that long to stop, due to the nature of that weight strung out over 2.5 miles of distance.

I once learned in a physics class that weight has nothing to do with the stopping distance, but rather the steel on steel friction coefficient.

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