- Norfolk Southern Locomotive Engineer Training Handbook For Monadnock State
- Norfolk Southern Locomotive Engineer Training Handbook For Monadnock College
- Norfolk Southern Locomotive Engineer Training Handbook For Monadnock Students
AAR control stand on an EMD DDA40X; Other EMD models are similar.A Control stand is a subsystem which integrates engine functional controls and brake functional controls, whereby all functional controls are 'at hand' (generally, within the operational radius of the locomotive engineer's left forearm from his customary seating position, facing forward at all times).Normally, a control stand is oriented in the direction labeled 'F' (front of the locomotive). Although front is usually the ',' a seldom-used alternate designates the ' as front. Where operations in both directions are required, two control stands (') may be provided. Norfolk Southern Railroad (February 2006). Retrieved August 2, 2015. Railway Technical Web Pages. Retrieved August 2, 2015.
Moller, Jeffrey (October 2013). Association of American Railroads. Retrieved August 2, 2015. Loumiet, James R.; Jungbauer, William G. (fourth ed.). Tucson, AZ: Lawyers & Judges Publishing Company. P. 91.
CSX Transportation. Retrieved August 2, 2015. DiFiore, Amanda; Zaouk, Abdullatif; Punwani, S. (John) (October 2012).
American Society of Mechanical Engineers. Retrieved August 2, 2015.
I generally have a good idea how one would operate a locomotive, but one area that I'm still not sure of, is how one would use the airbrake in varying circumstances. I do understand how a airbrake works, both the independent and automatic. I also do understand how you use the airbrake controls. So using that standard settings of bail/release, lap, set, and emergency, could you please explain how you would go about braking in the following situations. Please explain what combinations of dynamic, independent, and automatic brakes you would use. How many pounds of air you would set (or amps in the case of dynamics).
How far out in miles would you begin the set. The one element I'm really looking for is how much air does it take to do various things (how many pounds of air do you have to 'set'). For our purposes, let's consider the train to be 13,000 ton 115 car coal drag with three AC units. I won't hazard a guess at TOB, but just go with whatever is about normal for this kind of train.Situation #1You are cruising along at 60mph. Up ahead is the crest of a five mile long 1% downgrade with a 40mph speed restrictionSituation #2You are just passing a flashing yellow (advanced approach) at 60mph on level ground, meaning you're going in the hole at a siding with 25mph turnouts.
What would it take to come to a stop in the siding.Situation #3You're in a siding on a 2% downhill grade. A empty crawls by going uphill and you a get a green when he clears. The siding and turnouts are 25mph, the main is 40mph, but up ahead five miles is a 30mph restrictive curveSituation #4You are cruising along a 60mph on level ground coming up to a crest of a 1% downgrade that is three miles long with a 40mph speed restriction, after these three miles the grade flattens out for a mile before reverting to a 2 mile long 1% downgrade. The flat and this grade are still marked for 40mph.Thanks for any help on this.-Ted Curphey.
Ted,There are too many variables. You have grades: ascending, descending, how steep; tonnage, loads, empties, power; There is undulating territory where the train may be in 3 or more sags at once. No train ever brakes the same in the same place. How old is the power? The older it gets the less tonnage it will pull.
On your DB there are items like the allowable axles that can be used, of what type and what area. When was the last time you used the air, how much did you use.Its really a seat of the pants feeling knowing what the train is doing back there, what it shouldn't be doing and what you have to work with at that second or minute.If the brake valve is two position, (and on most US roads you carry a 90 lb brake pipe) and its in freight, it will take a 5 to 8 lb reduction in your first service notch.
The maxium reduction is 24 lbs or big hole is a 90 lb reduction. When you go to release the brakes you have to move the handle all the way to the release position before the air starts back.
In passenger you carry 110 lbs and with the brake valve set in passenger your set and release are graduated, still a max of 24 lb reduction or a 110 lb reduction in emergency.Like I said, there are too many variables to be able to point to one way to brake a train. There are two ways a hoghead can use the air.
The 'Velvet Glove' or the 'Iron Claw'. The main thing, if you are on passenger, DON'T BRUISE THE OLIVES IN THE MARTINI IN THE BAR CAR!Nudge. It really is not rocket science, and no two Engineers handle a train in the same manner. I run passenger trains so my knowledge is limited to them. For simple speed change reductions like you describe I like to use throttle modulation and the grades to control speed as much as possible, using as little air as possible.
A ten to twelve psi set will handle most slow downs. Dynamics will often be enough to handle grades on passenger trains but air can be used to supplement if needed. One of my early instructors use to tell me 'let the terrain brake your train' and he was and is still right. I have worked under hogheads from the Santa Fe the U.P. Guys are artists with the brake valve, most likely because they had to be.
Awhile back, a friend of mine wanted some general info on air brakes, so I threw together this web page:The text on this web page is reprinted from the Norfolk Southern Locomotive Engineer Training Handbook, and is provided as a general knowledge of how air brakes and affords insight into recommended train handling practices.Note: this was written in the early 90's when we still ran 75 psi as standard trainline pressure. Now it's 90 psi.It won't answer your specific questions, but it may not be a bad place to start.NS1. '26C' stands for '#26 Control valve'. 26-L stands for '26th brake equipment for Locomotives' and is numbered in the same series as 6-ET, which stands for '6th brake equipment for Engines and Tenders' and 24-RL which stand for '24th brake equipment for Road Locomotives'. As I recall, the 4449 uses 8-ET ('8th for Engines and Tenders'), and the MILW bi-polars use 8-EL ('8th for Electric Locomotives'.On long heavy frt trains, you don't play around with the brakes willy-nilly. On psgr, don't spill the soup. For our purposes, let's consider the train to be 13,000 ton 115 car coal drag with three AC units.
I won't hazard a guess at TOB, but just go with whatever is about normal for this kind of train.I'll try to get back to this when I get home if I remember but I have to go to work now. H-MEMPAS for 0700 that will most likely not get through the steel gang just west of town until 1530. I think I am going to die today. Not due home for 48 hours if they don't deadhead somebody out of Laurel.For starters:1. A 115 car coal train would be more like 16,000 tons. TOB = 133-136.2.
A coal train (or any train greater than 100 TOB) is not allowed 60 mph anyplace where I have worked. They are usually limited to 45-50 mph by rule. That extra 10 mph would make a big difference in stopping distance and amount of air set.3. Coal trains or any train that heavy that is operating on 2% grades would most likely have more power than 3 ACs. It would have extra units as helpers or DP and they would help with the DB.4.
I assure you that 13,000-16,000 ton trains going down 2% grades would be speed restricted to something like 15-25 mph and not permitted your 40-50 mph speeds at all.As a general rule for scenarios near what you describe, start early. Real early.10-14 psi should control most any train operating under more realistic circumstances.Going down Parkman (1.25%) with a 16000 ton coal train and 3 SD70MACs at 50 mph requires 9-11 psi to not speed. (It is VERY critical. 1 psi makes a big difference and it depends on the individual train. The Portland Roses have exellent brakes).But DB is MUCH more effective at lower speeds so on 2% with more units the air braking may be about the same.
SD70MACs deliver about 33,000 lbs of DB each at 50 mph but will be 70K lbs at 25 mph and can go as high as 87,000 lbs. Slower is better.I don't operate on 2%s and our 1.6% has a 25 mph restriction. I have operated on long 3% gradesbefore they tore out the Deadwood branch.
But the biggest trains I had on those were probably 4000 tons and speeds DOWN the grade were limited to 15mph. Up hill was 25-35mph if you could do it.AK. It sure makes running them a heck of a lot easier when you use dynamics. I used to run on the NS (back in 75# days)and if you were on a long descending grade once you had them bunched up you just controlled the speed with the dynamics.However there is truth to RUNNING BY THE SEAT OF YOUR PANTS. What is the weight distribution in the train? If your on train #111 with Coors tank cars and they're on the rear you better not spill the engineers coffee if your a student trainee (I Passed) You really have to know what kind of terrain the rearend is in.
Just a lot of different things to know and do. And you thought that all the engineer did was blow the whistle.:). The entire brake equipment conventional 26 equipped locomotives are called '26-L Brake Equipment'. The automatic brake valve is called '26-C Brake Valve' and the Service Portion is called '26-F Control Valve' for Locomotives.
The '26-C Control Valve' is used on most passenger/transit type equipment. There was a minor mechanical difference between the 26-F and 26-C Control Valves but that was done away with years ago with the exception of the NYAB equipped Superliner equipment. This difference was an additional path to charge the Control Reservoir directly from the Brake Pipe through a choke & check valve. This allowed the Control Reservoir to follow B.P. Pressure up during Graduated Release thus insuring a prompt re-application of the brakes when called for. This feature was eliminated on WABCO 26-C&F Control Valves early on.
On most NYAB 26-C&F Control Valves this option was left open to the end user via choke plugs 'X' & 'Y' on the side of the Control Valve casting.There are a variety of Brake Cylinder pressure settings for the Service & Emergency limiting valves on the 26-F&C Control Valves. Most Control Valves have a 'rejection' dowel pin on the Valve/Pipe Bracket depending on the part number so as to prevent the application of the incorrect Control Valve to a particular vehicle. This works most of the time.Both versions of the Control Valve had an Emergency Position on the Selector Valve early on but this position was eliminated with a spacer on the Selector Valve spool. To this day on early versions of the 26-C&F Control Valves you can remove the spacer and make use of the Emergency position of the Selector Valve as well as the Control Reservoir charging choke by adding such if need be.
Rwfischer wrote: AAK wrote: 16000 tons, 115 cars (139 tons per car), 3 SD70MACs, 50 mph down 2% grade. 5560 - 870 - 695 = 3995 LBS of air braking required per car. About 13-14 psi reduction maybe. Question: Could you stop this thing on the grade?Maybe yes, maybe no.
Norfolk Southern Locomotive Engineer Training Handbook For Monadnock State
If running down grade, the prudent thing would be to place the train in Emergency, set hand brakes then set retainers. Generally speaking, if the amount of reduction on the Brake Pipe is more than 12 - 15 PSI to control a train down grade, then it is time to resort to some other action, all factors considered.
Norfolk Southern Locomotive Engineer Training Handbook For Monadnock College
If all the cars were doing their fair share in the braking of the train and were loaded not beyond their load limit then it would be possible. This is usually not the case though. Should be able to. Once you have balanced the grade with airbrakes & DB then the train will operate as if on level ground.
Norfolk Southern Locomotive Engineer Training Handbook For Monadnock Students
So a normal set of additional air brake should stop it normally. To make a standard stop you'd need about 10 psi more so that would bring you up to about 23-24 psi reduction. It should stop but it had better be fully charged from the begining because there is not much room for error. 3 more psi and you are at full service. F course you always have emergency left. The wheels and especially the shoes are going to get very hot and I don't know what effect that has on their ability to produce drag.