Steam engines being pulled

A reasonable question for Hot Water to answer for sure. He's the absolute authority on this forum when it comes to anything having to do with 'real' steam engine operations.

Not sure I've ever heard of a scenario like you describe.

I try not to get involved with post from this guy, as they generally are not real clear and tend to go no place.

So, I'm with smd4 on this one also.

I've never heard of an engine being "pulled in a train...to save water". Shoved along because of 'other reasons', yes..

DV

Back in 60 on one of the Michigan Railroad Club fan trips, GTW 6322 blew a cylinder packing causing huge steam losses, enough that they ran out of coal out on the line. A diesel was sent out to drag us back into Pontiac where the packing (and coal) was replaced and we proceeded to Detroit albeit much later than anticipated. The big concern was keeping up the cylinder lubrication while under tow. If I remember correctly, it was less than ten miles of not very speedy running.

I think what Ironlake2 is referring to is the use of a diesel to "stretch the coal" as we have done on our long deadhead moves on Norfolk Southern. It's not done to save water...taking water is easy compared to taking coal.

On a long trip (250+ miles) we may choose to run at a lower pressure just to save coal. It doesn't take as much coal to heat the boiler to make only 200 pounds of steam as it does running it right at the limit at 245 psi. We'll work the steam loco just hard enough to pull a light draft on the fire and use the diesel for the additional horsepower needed to maintain the speed.

Thanks rich for understanding my question.  Hot water, I just watched the high def video by pentrex on the 844 and is it being pulled backwards in a train by a diesel out to a place where the train was to be turned on a wye.  That is what prompted the question, was the 844 running on reduced steam pressure while its power was not being used. 

No. I always kept #844 or #4449 or #3985 at full boiler pressure on such moves because we would have to go to work soon thereafter. At least when I was fFireman, since it is much easier on the firebox/boiler to maintain a constant heat/pressure environment.

Lower pressure = lower temperature. When the temperature goes down, the engine contracts-not a good thing. I can see why Hot would want to keep things mostly constant. Too much expansion/contraction is not good for a boiler.

One of the guys that came to Greenfield Village from the Strasburg Railroad when we had their Thomas the Tank engine here managed to stump me with a question about keeping up steam pressure.

If you're going over a long down-graded section of a railroad (drifting) using up little of your steam to keep moving, why is it important to keep the boiler pressure up?  

I'll give the hint, that though temperature changes is important, he gave a different reason as well.

I can't wait to hear your answer!

Well, I took his word for it, but he said you want to keep the air compressors running at full power so you can recharge the brake system quickly so it's ready to go when needed.

On smaller,i.e. lower boiler pressure locomotives, that is true. However, on the larger main line "big steam locomotives" having working boiler pressures of 240psi to 300psi, keeping the dual cross compound air pumps "working at full capacity" really isn't that much of an issue. With main reservoir air pressures of 140 to 155 psi, obviously the boiler pressure MUST be kept higher than the main reservoir air pressure in order for the air pumps to keep working. Thus, maintaining full rated working boiler pressure is much more important in order to maintain temperature related stresses within the furnace system. Also, after the "long down grade" the Engineer will quickly have to open the throttle in order to maintain train speed, so the Fireman had better be prepared for THAT! 

I think your final point about having to go back uphill and needing to open the throttle is the answer I came up with when he asked.

Our two operating locomotives run at about 125 and 150 psi, so that's kind of what we were using as an example (he was probably thinking about one of their locomotives as well).  Ours also have single stage compressors.  I believe at least two of Strasburg's locomotives (Thomas not included) use the cross compound type.

Anyway, it was something I hadn't considered.  Of course I had also never realized how noticeable even a small grade is when you're running a locomotive

I used to operate a H. K. Porter 0-4-0 saddle tanker converted to a 2-4-0 and tender in tourist service. Saturated steam, Original design operating pressure of 200 psig, but safeties set for for just over 180 simply out of respect for a machine built in 1934.  With a single piston air compressor keeping up the pressure on a downgrade was critical.  I can tell you going downgrade for over two miles with a three cars of passengers or sometimes more, and backwards by the way, was always nerve racking because if you set the brakes to hard to start with might not have time to recover the air fast enough if you had to kick it off.  Never had an actual runaway problem but there was always some serious mental algebra going on concerning how much of a reduction to make, when to start putting it on and if I had to release the brakes, how soon would I be able to put them back on. 

As to pulling a locomotive to stretch coal reserves this seems to be a moderen mainline occurence only.  I can't think of any historical reason that you would pull a steam locomotive hot.  For short dead head trips you would lash open the cylinder cocks and make sure the mechanical oiler for the cylinders was topped off.  If the engine was to be moved further the main rods would be disconnected from the drive rod.  (FYI - In moving diesel electrics it is still a rule, to my knowledge, that the wire leads to the traction motors have to be disconnected.)  There's more to it than I mentioned here but I've been out of the game for a few years and those are the highlights that come to mind.

Absolutely NOT true! Diesel units have been hauled "dead in tow" from the day they depart the manufacturer, to the day they are traded in or scrapped, and the traction motor leads are NEVER disconnected.

Towing a steam locomotive dead, i.e. no steam pressure is a different situation.  Towing a steam locomotive under steam really isn't that big a deal, so long as someone is in the cab to open the throttle a bit and operated the power reverse gear, in order to provide steam & lubrication to the pistons/valves while moving.

Keeping air pressure is ALWAYS critical, no matter what kind of engine you're running.  Even with a consist of modern diesel-electric units it's still possible to "**** away your air" if you make successive reductions without allowing enough time to recover.  True, the smaller compressor makes some difference but this is something any engineer faces and learns to avoid.

A couple years ago, a friend (who is a former locomotive engineer) and I rode a Horse Shoe Curve excursion at Railfest, behind the restored PRR E8 units.  I'm not sure who was running the train at the time, but whoever it was set too much air coming down the grade, and proceeded to make a running release, then set the air again.  A bit nerve-wracking...

Rich,

When an engine is under steam and being towed, how and where do you set the cutoff? I assume that it is set a little on the "long cutoff" side so that the valves and cylinders receive adequate lubrication? And are the cylinder cocks left open? How do you decide how much to "crack" the throttle? Back pressure?

Or is it some combination of the exhaust (probably shallow?) and the sound of the rods?

Thinking about this, it probably entails just as much work as running....!

Hudson5432,

I don't think Rich's answer will differ much with how Doyle McCormack "drifts" SP 4449, nor how Steve Lee "drifts" either 844 or 3985:

Whether drifting down grade or being "assisted" by a trailing diesel helper, the throttle is reduced to the closed position. Then, open the cylinder cocks, and open the throttle until steam vapor is seen and heard escaping the open cylinder cocks. The cylinder cocks can then be closed (and remain closed). The reverse gear is placed in full forward position, then pulled out of the "corner" about 3/4", thus preventing the link block from constantly riding at the bottom of the link on the Walsharts valve gear arrangement (this is not an issue with Baker Gear).

The resulting "open" throttle (which is actually just the pilot valve being open in the American Multiple Valve Front End Throttle), prevents a vacuum from being pulled on the smokebox, provides steam oil lubrication to the vales & pistons, and provides some semblance of draft for the Fireman (VERY important on large oil burning locomotives).  

Hot Water,

Thanks for the explanation. I forgot that the UP844 has Walschaerts!

With the automatic brake valve and the control valves on the cars set to PASS position (which would be expected on a train consisting entirely of passenger cars), I cannot understand why the Engineer had to completely release and reapply the brakes.  Why did he not simply graduate off some of the reduction and pull the train a little to get the train up to the desired balancing speed?

Drilling deeper toward the root cause, why did the Engineer make too deep a brake pipe reduction in the first place?

All good questions, Tom.  I don't know who was running the engine, as I was not in the cab- but an NS road foreman boarded the lead unit before we left Altoona.  I also know that these units were/are equipped with 24RL brake equipment.  I'm wondering if, perhaps, the engineer and/or RF weren't familiar with the 24 brake?

  IIRC, 24 does not have a pressure maintaining feature as the automatic is not a self lapping brake valve. With the brake valve in lap, the leakage in the train line, depending on severity, will slowly diminish the brake pipe pressure causing an increasingly harder set... You cannot make a set with a 24, or an 8ET or 6ET for that matter, and expect the brake pipe pressure to remain the same.

I hope Jack, Rich or Ed can comment further..

DV

Because the passenger cars we use often move deadhead in freight trains, they are not set up for Graduated Release. The 26 brake valve on the 765 is capable of Graduated Release, but the cars are not set up for it. This may have also been the case with the E8s.

The 24RL can be set up for First Service and Pressure Maintaining. I'm not an air brake expert, so I don't know the specifics of what has to be done to set it up that way, but it can be done.

First Service gives you about a 6-7 pound set, just like Minimum Reduction on a 26 brake. When set for First Service and Pressure Maintaining, I prefer the 24RL to the 26. If I need only 1 pound more air, I can easily get it with the 24RL. It's a bit of a crap shoot to make such fine adjustments with a 26.

Learn something new everyday; thanks Rich!

DV

Actually, in the mid-1950's, the Pennsylvania Railroad worked with Westinghouse Air Brake Co. on modifications to the 24-RL automatic brake valve, to allow First Service position to become Pressure Maintaining position.  I would assume that all PRR locomotives with Number 24 air brake equipment received the modification, but I don't know what brake equipment is currently installed on the restored E8's, which are not "one owner" locomotives.

I was being a bit coy in asking why graduated release was not used to reduce the brake application.  If I were running an excursion, I'd send a Car Inspector with a wrench to turn the caps on all the control valves (including the locomotive) that were set for direct release, and make sure that the Engineer set up the Rotair valve for PASS.  (Or, if the locomotives have been modified, turn the cutout valve on the 26-C automatic brake valve to PASS.)  That way, the train could be handled very smoothly, using graduated release of the brakes.  Maybe they did this; maybe they didn't.  Either way, it was their choice and not mine.  The other item of interest is the experience of the Engineer (and the Road Foreman of Engines).  Event recorders and train handling rules aimed at fuel economy are producing more and more Engineers who are not highly skilled in the handling of trains by use of the air brakes.  This is not their fault -- they are not allowed to use the air brakes at will, and event recorders now automatically report exceptions to Company rules about the use of air brakes.  They just don't get an opportunity to use the air very much.  If they are really sharp, they can think through scenarios for handling a passenger train with a non-dynamic brake equipped locomotive on a descending grade, but, frankly, this is something none but a few have done.  Most Engineers still carrying a license don't even know that, after making a graduated brake pipe increase to lighten the brake application, pressure maintaining will no longer work until a subsequent brake pipe reduction is made. So, you see that handling a 15-car passenger train with a pair of engines not equipped with dynamic brakes, on a descending grade, is a job for an Engineer who actually knows the air and how much braking to use at what speed, when to initially apply the brakes, where the train is going to try to run or die as it descends the hill, how much wheel heat is being produced, how to think ahead of any throttle or brake use to analyze the train slack consequences, what he is going to do if something does not go as planned, etc.

Excellence - it was once an integral ingredient in operation of a North American passenger train, and still is, sometimes.

My question albeit somewhat related but broached here be ricochet is can and/or how are dead steam engines pistons/packings lubricated while towed?  I have seen picture from back in the day of strings of new steam being delivered.  Are the steam in consist under steam?  Also relates to strings of steam being towed to scrapping

Towing a dead steam locomotive is a whole different ball game! NONE of the reciprocating components normally lubricated with steam oil, MUST be allowed to move, i.e. the pistons & valves, plus the crosshead.  The most common method was simply to remove the main rods, and eccentric rods. Although that naturally puts the main driver slightly out of balance, prudent speed restrictions during shipment allowed all new steam locomotives to be carefully & safely shipped "dead in tow" all over the U.S. and Canada.

No, new locomotives would not be under steam, but a mechanical lubrication system would be installed for transport.

As far as loco's going to the boneyard, the main rods might have been removed, or even the piston rods torched off.  There probably might have been some manual oiling around before moving, but with the torch being the future, it would have been very basic.

Rusty

Rusty thanks for info.  I have been meaning to bring this up for some time.

A mechanical lubrication for machine oil is NOT the issue, Rusty. The reciprocating components that require the steam oil can NOT really be properly lubricated without steam flow. Thus, the main rods, etc. must be removed. 

You're right Hot.  I should have clarified that.

Anyway, for those still listening, here's a photo I located of a Cab-Forward in transit.  I believe the location is somewhere around Kansas City:

Note the main rods are off.

I think it was Classic Trains that recently published a photo of the oil drum set-up on the platform of a Cab Forward for the mechanical lubrication system.

Rusty

Hot Water, thanks for the informative reply.  I do not know how I missed it before seeing Rusty's.

I then presume then the rods were on flat cars with the engines.  So were the rods marked for a specific engine or totally interchangeable?

Hopefully I will run across these pictures of steam in delivery again and pay close attention to the missing rods.

Ron

No, each individual locomotive's rods were generally placed in the coal bunker of coal burning locomotives, or on top of the tender on oil burners. The main rods were labeled for EACH side, and on articulated locomotives for each engine, plus left and/or right side. Naturally, the rods would have been removed from the tenders by overhead cranes, as the "set-up" procedures was done at a shop or roundhouse.