Steam Locomotives and Oil Firing

An Andrew Barclay

And Germany... (Oil fired locos were still running on the mainline in revenue service in Germany at the same time Bahamas was last hauling railtours in the UK) -1991.

I recall at Trier in 2010 seeing a 41 "turned off" in the yard for over an hour at the station.. It really was completely uncannily silent and not a wisp of steam from it either.... But within a few minutes the burner was on (you hear the low hum -it sounds like an elephant taking a pee- don't ask me how I know this) and it pulled off, reversed on to its train, so it's presumably not so draconian to heat up after standing long periods.

I recall a German driver saying the German locos have two burners, rather than one larger one, together with and a "z" shaped arch to allow a slower heating / control and to take the harshness of the flame away from the boiler.. Don't know how true that is..

There's at least a dozen oil fired locos operational in Germany across 01, 03, 18, 35, 41, 44, 50
My avatar 18 201 is an oil fired beauty, and carries both oil and water in a second tender.

If oil firing was to be considered in the UK I'd suggest popping in to a German preservation group for a chat..I'm sure they'd be very hospitable and there's quite a bit of mainline experience / even oil fired operational experience to hand.

 

Or a Bagnal, in New Zealand:

http://mainlinesteam.co.nz/bagnal.html
https://www.flickr.com/photos/nzsteam/5040581130/in/set-72157624945005273

Tom

 

GPCS was tried by the SAR, not a new idea at the time, and one of the main, if not the main aim of the trial was to avoid lineside fires and their associated costs. It is not a perfect system but does offer significant advantages over the traditional, spark throwing combustion fitted as standard if burning solid fuel. But many of you will know this....
So, why not try it? It generally produces cleaner combustion too. One potential drawback would be the substantially increased power output. Bearing in mind events of the not over distant past the subject of any such modification may well need some attention to mechanical and frame details.

 

I'm intrigued. How does a gas producer system increase power substantially?

 

I'm surprised the Claud Hamilton new build group haven't been getting in on this thread, though it would be a bit small for most main line work

 

Funny, I'd wonder if it were the other way round: the purists would be keen but the ordinary punters wouldn't fancy the exhaust fumes from burnt fuel oil. I know I wouldn't.

 

Not sure if you've had much experience of travelling behind oil fired steam locos on the main line?

My extensive experience in Germany, East and West, behind such machines since February 1971 is that if the burners etc are set correctly there are little or no offensive exhaust fumes. Just a lot of noise with the right crews as oil fired locos don't tend to throw their fires when worked very hard indeed.

And, as an aside, it is great to be on the footplate watching the interaction between driver and fireman, different than on a coal fired loco. There is a more immediate need for the fireman to react to what the driver is doing. I shall never forget being on the footplate of pacific 012 100-4 as we climbed the Rendsberg spiral onto the massive Kiel Kanal bridge. "Utter Thrash" is the only way to describe how V was driving on the climb. Full regulator, of course, and something around 50% cut off. Burners on full. Then a mad dash to shut off and brake down to the very low speed limit over the bridge, wonderfully anticipated by fireman T who got his timing just right in turning the burners right back down.

Only issue up front is that you have to lean out of the cab to hear the thrash as the noise of the burners and the constant blow of air over the fire grate tends to partly drown out the exhaust noise. A small inconvenience I found!

First did that climb with big bruvver on the Southbound Nordphiel Express back in April 1971. Several coaches back and a stupendous experience on quite a heavy train.

 

One of the suggested causes of the troubles with Flying Scotsman was the use of a 250 psi boiler on frames originally designed for 180 psi and, even in normal A3 form, only 220 psi, thus increasing the maximum piston thrusts. Changing the combustion system on a loco to either gas producer or oil wouldn't affect the maximum forces. But either of those changes would increase the amount of steam available, so the loco could, and probably would, be worked at higher speeds and/or for longer periods at the same regulator and cutoff settings, and that would increase wear and tear.

And presumably any such conversion would require new main line certification.

But none of that is insuperable, so it seems to me that there is a very good case for trying both GPCS and oil firing on at least one loco each, existing or new build.

 

Totally agree. And infinitely preferable to some of us to listening /smelling diesel fuel being compressed under a cylinder head. Which seems to be all that has been available on "steam" trips in one part of the UK for some weeks now.

 

Locos lit up from cold were warmed up very slowly by lighting the fire for ten or so minutes then turning it out and putting the chimney lid on to allow the residual heat to warm the boiler through evenly. The process would then be repeated several times. It was very rare that a fire would be lit in a cold loco and left on until there was steam in it. An engine that had been out the previous day could be brought up to pressure in under an hour if needed but this only really happened if another engine failed.

All the FR engines have steel fireboxes and traditionally the tubes would be welded in at the firebox end. Also several locos had the fire hole enlarged to reduce stress in this area. I can't think of one that has suffered problems caused by thermal shock but then again these are relatively small boilers compared to a mainline engine.

Tim

 

With the more traditional form of combustion you reach the stage where the primary airflow through the grate carries away 50% of the fuel that you try to place upon it. With GPCS the emphasis is on secondary air, that is air that is fed into the system above the fire bed, simple when you think about it. Less air drawn through the fire leads to less fuel lifted off it.
Additionally you feed steam to the fire bed to keep it below ash fusion temperature. The secondary air flow is designed to prolong the amount of time small particles remain in the firebox. If you burn them the steam production benefits and the lineside has less chance of going up in smoke.
The system produces a high draught loss so you need the exhaust design to drive it. This by extension gives low back pressure and improves the indicator diagrams. So you not only obtain a higher grate limit and hence more steam that you can use but you also have improved cylinder performance.
I am not saying that it is easy to get the best results. But there are people that have done it. It isn't perfect. But it sure isn't oil.

 

I more or less understand how the GPCS works and the benefits gained through less fire throwing but if nothing else on the loco is changed, how does the system increase power output by any significant amount?
IIRC the KWVR had two Austerities with GPCS, oner arrived with it installed and the other was a post preservation conversion.

 

If the exhaust system is not changed then overcoming the draughting loss becomes an issue. The exhaust drives the combustion and the GPCS needs adequate driving in order to function. The primary air is drawn through a pinhole grate and much turbulence is generated in the firebox. That aside the system allows you to drive the boiler harder because the amount of unburnt fuel being ejected to no good purpose is very much reduced for a given evaporation. It appears that it is very hard to reach the 50% ejection quantity which represents a performance brick wall for the conventional locomotives when using GPCS. It becomes more of a theoretical limit.
What you achieve is a boiler which provides more steam simply because it can burn fuel more effectively. If you have more steam that you can use then more sustained power is available to you. You may not need the extra evaporation all the time but it is useful to have it available. For a given power output the rate of fuel consumption is reduced, this saves money, minimises lineside fires and eases the load on the fireman. Further the reduced carryover minimises char cutting.
The underfed system as fitted to some austerity 0-6-0st locomotives is a mixed bag of virtues and vices, the grate area gets reduced and the fire can track back into the bunker. This system would not be the one being proposed.

 

I know some locos which did have GCPS subsequently had it removed (e.g. River Esk). Anyone know why?

 

IIRC Wardale said that GPCS was only worthwhile if a loco was being fired/driven to its grate limit so perhaps that's the reason behind the removal.

 

As a member of the 2860 crew here in Canada , when we run her on the mainline we use recycled motor oil as fuel , meets all our needs and is relatively cheap as opposed to diesel fuel .

 

You could oil fire if desperate and there were no other options. But it would hardly provide the British steam experience. And there are options.
If you can burn coal, have greater efficiency and power output in addition to solving spark emission problems why not do so?
If the balance of air flow is changed so that by far the bulk of the combustion requirement is no longer supplied through the grate and hence through the fire bed where is the problem in that?
I suppose it comes down to what is the cheapest, easiest option. What is most easily understood, presents the minimum challenge. The quickest short term fix.

 

hmmm...

sounds like some convincing on sound is needed.
The video isnt the best.. but it's not about the video.
Here's a Br41 2-8-2 departing for Trier in 2010 (the same one I said was sitting quietly in the yard for an hour in an earlier post). Would be nice if Britains next 2-8-2 also sounded like this, and possibly Oil fired too ??




I challenge anyone to say :

a. This sounds quiet.
b. It sounds different to coal fired.

 

Bet it smells different though.

And on the subject of burning recycled motor oil. Why? What a waste. Better to re-refine it, reload with the all important additives and use it again. The only reason to use it in a locomotive is if you are stuck with an oil burner and need to run it cheaply, though I question the ethics of burning what is going to become a scarce commodity when there is an alternative.

 

Not massively, though after a few hours out of the window you tend to get a bit oily.. instead of goggles to stop coal grit in your eye, a scarf for your mouth is advised.

here's another.. two oil fired locos side by side at Bullay.
01.0509 passing 41.360 (taken from the front coach of the 01's train), you can just hear the rumble of the oil burner of the 41 as we pass it.


and another at speed..