Does a unit train of say coal,handle any differently than a similiar train of mixed cars?
Yes.
Both ways.
O.K. Poorly worded question. How do they differ?[
]
Loaded unit trains carry coal, and empty ones do not. [8D]
Murphy
That is kind of a loaded question. Are you asking 2 trains of same length but different tonnages or 2 trains of same tonnage and different lengths?
Lets say train length:
4800 foot coal train 80 cars about 12400 tons: very solid but requires a lot more stopping distance because of high ton to brake ratio. Harder to control speed on hilly terrain as either the whole train is going up hill or down hill.
4800 foot mixed train 80 cars maybe 6000 tons: more slack action on account loads and empties mixed through train. Likely feel alot more run ins and outs but brakes a lot quicker account of lower ton to brake ratio.
Lets say tonnage.
12400 ton 80 cars 4800 feet same as above coal train…
12400 ton 140 cars 8500 feet with mixed loads. A lot of hard run ins and outs and hard to control slack. Braking can be a problem as train length takes a long time to brakes to set up on the entire train and also takes along time for them to all release. General speaking easier to control the speed as a train of that length part of the train maybe going down a dip while the other part is cresting a knoll so it kind of averages out.
This is only a very general idea as there are so many other variables as marshalling etc.
Brent
every train…and i mean EVERY train handles differnt… some are a fight form one end of the road to the other… even if you take 2 unit trains… both loaded to the same weight… the both will run differnt… due to the power (or lack of power) assined to the train… the condition of the brakes on the cars… the list can go on and on… every trip is differnt…evey train is differnt…thats about the best way i can sum it up
csx engineer
You have got that right CSX in the short time that I have been a permoted engineer (4) months lol I have found that out the hard way at times but live and learn as long as it stays on the rails lol.
Rodney
I would much rather run a 19,000 ton coal train than a 7,200 ton junk train. On the coal train the cars are almost all the same and the brakes seem to work better.
Rodney
Rodney: Is that because the coal cars are all about the same weight? Or are the coal cars kept in better mechanical shape?
Even a little 8-car MU electric train will handle differntly depending on the consist. Every consist is a unique consist and will do different things in terms of train handling.
Mitch
The coal hoppers aer almost all uniform and they just seam to have better breaking than a mixed frieght.
Rodney
the big differance in trains is the braking with so many type of brakes a mix train will stop differantly than a coal train . a coal train has all the same brakes . all the cars of a coal train are lo9aded equal so theere wont be any suprises. all cars are the same also and no run in or out. now on a mix train you have differant draw bars differant brakes differant loaded weights thru out the train the key to running a train is you control the slack and the train not let it controll you . Know your territory and you will run a smooth train … their is one exception… there is alwasy the 1 train out of 200 that no matter what you do it wont be smooth always trouble and your glad to get off it.
So, until you run a particular mixed train for a while, you don’t know just exactly how it’s going to react? Or can an engineer look over a train beforehand and have a pretty good idea what to expect?
Try running a GP38 with a 7 car local going up a 1.75% grade and then running 5 SD70MAC’s and 150 loaded coal cars and you will see the difference.
Right you are wabash I was running a vehicle train the other day and had runout going downhill and runin going uphill I had the road foreman of engines on board and asked him what that was all about all he said was those slinkies will get you everytime.
Rodney
gp 38 and 7 cars easy add 4 more gp 38 and 50 coal cars loaded and have fun and as far as 150 loaded coal cars that is not a problem the 5 70 macs is the problem as you cant have more than 32 axles on line. 5 puts you over big time. 45 powered axels is alittle over.
murphy siding
You can look at the paper work and tell what kind of train you will have. It is very seldom that a train will throw suprises at you pulling out of the yard i can get a feel of what it is going to do. once on the main and headed for the yard board you can tell real quick how it accelerates how the dynamic brakes are.
Absolutely right, autorack trains are big slinkies but my road usually doesn’t put enough power on them to do anything with them.
Every train handles differently and you’re right, Wabash, you get that train every now and then that just mystifies you, there’s a surprise in there somewhere. You’re always glad to get off of them.
You are right about that valleyx.
Rodney