"Setting a retainer"

Trains Magazine General Discussion
21

Depends on the Company Rules and the Special Instructions. Variabilities include cars with in-operable brakes, per-cent of the grade, curvature, distance for retainer use, weight of the train (remember Tons Per Operable Brake?), dynamic abilities of the locomotives among some of the considerations.

And, just to add a little confusion for you, although the retainers would normally be turned up at the top of a grade, that may not be the case. It has been known for crews to be required to use retainers going up a grade as well as down (really rare), and if a crew is waiting for another train someplace over the other side of the retainer district, they can turn up the retainers there, but if they do and they need to use the brakes prior to the summit, the brakes on the cars that have been turned up will stay applied and probably stall the train.

AND … If the lead unit of the train has its brake system incorporating the pressure maintaining function (all units built new in the last 25 or so years – at least --) may not be required to use retainers. As I remember, Saluda is pretty short and I think that a stop for wheel radiation or resetting of the retainers would not be required. All that would be required in this case is a “blow and go” or a running test.

22

…I certainly don’t have an answer to the above question…Recently in articles of some of the “passes” out on western lines {and I’m not sure if that one is still operating…but I believe it is…the Raton Pass…was mentioned to have grades of up to 4%…I would think retainers might have or still would be envolved on that down grade…but I for sure dont’ know…I don’t remember any conversation about retainers on the eastern roads in the area I originate from…Ex. B&O and Pennsylvania…and near by B&O banches with grades of up to 3%…And back then was before any dynamic brakes…And those were heavy trains…Hauling coal.

23

Until diesels and dynamic brakes, the brakemen could be required to “decorate the tops” (climb up onto the car roofs to operate brakes) to operate the handbrakes or the retainers. This was not really safe (for several reasons) but since all that was available for communication was the hand signal or the locomotive whistle, it was the safest method available.

Retainer rules (and also the retainers!) still exist so that trains can be safely operated down “steep” or long descending grades without dynamic brakes or pressure maintaining system of the air brake being operable.

The classic example of this is the runaway that the SP had that derailed outside of West Colton dumping the entire train (including the helpers) and killing a bunch of people. Had the crew known the true weight of the train and the true numbers of in-operable dynamic brakes, they would have turned up the retainers and we would have never known about these people.

24

…Eric…You may be familiar with what Saluda looks like and if so…you might agree it’s hard to understand how anything could be pulled UP that grade with some retainers set…
By the way, Saluda grade: Several miles.

25

Perhaps I should clarify on using retainers while ascending. It was to keep the train from rolling back when the trainling weight behind the road locomotive exceeded the holding power of the independent (engine) brake. Prior to release of the brakes, retainers would usually be turned up to hold the train during release and equalization should the situation exist for their need. This procedure was really a “knuckle buster” and “harassment” if you didn’t really need it because the rear men (Conductor and Rear Brakeman) would be running up and down the rear of the train turning retainers up and then down just to keep the train from rolling back, and then once moving, so that the train would not stall. It was plan “Z”.

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Huh? Wouldn’t the retainers make the train more likely to stall on the way up?[%-)]

27

Read the last two sentences again. It is either use hand brakes to hold the train or retainers. Either way, the rear end crew runs up and down the train like track stars turning the retainers up and down or tying and releasing hand brakes. And trying not to get left behind.

Also, forgot to mention – this manuver is nearly impossible to accomplish with only a head end crew.

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Question: I’ve seen images {and personally been there to see it}, of heavy {coal trains}, decending Horseshoe Curve grade down into Altoona with smoke billowing from brake shoes of the train approaching…Have not heard any stories of the train stopping to “set retainers” before decending that {12 mile}, grade…What is the difference…Some grades, set retainers and others not…If the train would get away on H S grade it would be just as dangerous as perhaps some other downgrade…So if brakes work satisfactory controlled by the engineer in that case why don’t they work as well {controlled by the engineer on some steeper grades}…?

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Page’s 93 through 101 of the April 2004 issue of Trains describe getting a train down a mountain grade-pictures and an explanation and illustration of air braking systems too.
[:)]

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…Yes I know I have that issue on mountain railroading and breaking concerns…

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MODELCAR … The reason for the use of retainers is to control the speed of the train and permit the train to recover its air so that it can stop properly and control the speed properly.

Dynamic brake usually does this quite well.

When the weight of the train exceed the alowable dynamic brake capacity (will be stated in the Timetable, Special Instructions for each district or grade), then the air must be used in adition to the dynamic

Depending on the specific conditions, the engineer may be able to make the proper reductions and while the brakes are released, there can be time for the system to equalize prior to the next reduction. In such cases, no retainers would be used - only the automatic, and you would get smoke from every wheel.

The amount of reduction and its duration also dictate whether or not retainers will need to be used.

To illustrate: one grade I have worked on has, from the top, descending, 2 miles of 3.3%, 2 miles of 2.75% and 4 miles of 1.8%, 2 miles of .5% ascending and almost 5 miles of 1.8% descending. The Special Instructions permit no more than 30 Axels of operable dyanimic brake for 1st generation units and 18 Axels of operable dynaimic brake for any engine consist that has Extended Range dyanimics operable (even if it is only 1 axel of ERDB).

If the engineer can control the speed with the dynamic only, then no air will be applied. If air is needed for the 3.3% part, than the engineer probably won’t use retainers but stay with the automatic and release the brakes byond the 3.3% portion.

But if the train is of such a weight that the engineer must use the air on the 3.3% and the 2.75%, he may have the retainers turned up or not (his/her choice) but would have to stop for 15 minutes at the end of the 2.75% to cool the wheels.

Should the engineer need air the entire length of the grade, then he would have the retainers turned up at the top (the Special Instructions will give the

32

kenneo: Did those trains we’ve all seen in pictures, hauling coal down some mountain in PA or WV, with all the blue smoke from the brakeshoes have to stop at some point and let the wheels cool down?

Thanks

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Eric: Thanks for the list of data you provided in examples and I’m sure from experience in doing some of the mentioned processes. Seems the engineer has quite a bit resting on his shoulders upon making decisions at the summit how he is going to control his train down the hill in front of him…I would think he must feel a great bit better if he has…say 5 6-axle engines with good working dynamics to draw from…Retainers or not…ha.

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The key factor in whether a train needs to set retainers is “Tons per Operative Brake”. On most railroads anything over 100 tons per operative brake will require retainers to be set.
Another factor can be effective axles of dynamic braking, there is a limit on how many locomotives in one consist can be in dynamic braking. Too many and the train can do the opposite of stringlining. This is why you will see up to four helpers on the rear of loaded coal trains descending though Horseshoe Curve. Normally with enough working dynamic brakes there are only a few grades in this country that require retainers to be set when operating heavy bulk trains. All of them have gradients of 2.5 percent or higher with a single exception. They are Cajon Pass (south track), Raton Pass, Soldier Summit east slope, Cima Hill, Blue Mtns, and Saluda Mtn. Cima Hill is the only gradient that isn’t over 2.5 percent. It is also the location where the North American speed record for a loaded freight train was set, when a loaded welded rail train lost its brakes on the west slope. The speed recorder logged a speed of 115 mph. but based on signal block logs estimated speed upon derailing was 130 mph. It is a straight shot from top to bottom with a curve at the bottom. The Blue Mountains on the UP in Oregon are the only grades where retainers are needed very often, with the introduction of DPU they probably are too common there anymore either.

35

…Interesting info…Are you saying if too much resistence is used up front as in dynamics the weight of the trailing cars would buckle them off the track to derailment…?

36

Depends on how long the brakes needed to be set. Some of those spurs were short enough to no need wheel cooling stops.

37

Yes, all those axels are a comfort. There are a set of rules and formuli that the engineer uses to make his decision. The road I worked for made it real easy. Divide the gross tonnage of the train by the number of brakes that are working (usually, all of them). Compare that resultant number to the entry in the Special Instruction for the use of retainers and if you have a bigger number for your train, you turn them up. If not, dynamics away down the hill.

38

Absolutely. Without fail.

39

Get real guys! In the steam era, a train might have a half dozen brakemen or so on steep downgrades to handle the braking. Now, a train might have two crew members who aren’t “walking on the rolling stock setting retainers”, and definitely no caboose. Diesels’ dynamic brakes revolutionized down-grade railroad practices for the last half century. Also, on the “uphill” no more time watering several locomotives spaced throughout a train. Yes…the “good old days” are great for modeling, but if you are a “real” railroader (especially a brakeman), would you want those days?

40

markpierce…You aren’t saying that retainers aren’t used at all any more are you…? There evidently are places that require the train to stop on summit and set retainers…I know that was the circumstance down in NC at Saluda before rail operations were haulted on that line roughly 4 years ago…