Advanced steam tech for narrow gauge locos

P'raps a "special Bracken Green"?

 

To be honest if someone has used it, I think we would have heard about it by now, this suggests to me that it may not have been so successful as it suggested.

 

Was fitted to 160A1, was spec'd for 5AT boiler.

 

My take on this, for what it's worth (!) is that as the Chapelon application seems to date from the mid 30's, I suspect the combination of top feed and scale tray, which found favour in the UK, probably performs the same function to some degree. I could conceive of such a device improving the efficiency of a rather disproportionally long boiler, moreso where top feed isn't an option for whatever reason. Can anyone think of a design meeting that criteria?

I can't see any reason why the Chapelon mod would impinge on external appearance one jot. If so, some computer modelling by someone suitably qualified might well be worth undertaking to see if any identifiable and cost-effective efficiency gain is to be had.

If considering some completely new design, permit me to get my two penn'eth in right now regarding one particular development. The Franco-Crosti system, aside from being one of the fugliest carbuncles ever visited on the classic lines of a Stephensonian steam loco, seems to do too little to justify even complaints from traditionalists, let alone the inherent additional maintenance burden which unavoidably comes with it.

 

Thanks for that 1802 just had a look, she was a big old beast to say the least, to be honest I am not sure that this device would be of any use on a narrow gauge loco, the current thinking for 2ft gauge locos is short, fat and as big as you can make it to fit the loading gauge.

One bit of good news is that I have just found my Baldwin drawings for the NG10 class loco so building a tender for phils loco is not going to be a problem.

 

Oh My Goodness! What is the wheel arrangement, do you know? If its a 2-4-0 or 2-6-0, then it is my dream machine-the one I'd spend my lottery winnings on. Exactly what a certain railway could use, if M-Ws are going to take as long as Lyn to get from inception to completion. Put me down as a contributor if/when the hat comes out.

 

I tend to agree with you about the Franco-Crosti design, I read somewhere it may have been in one of my boiler books that the concept was to try and get a second pass of the hot gases from the firebox, I need to go back and re read it, but enough to say that it was not the success that on paper it could have been for a railway locomotive yet the funny thing is most domestic boilers we have in our houses can be a three (or triple) pass boilers, IE it doesn't go straight from the flames to flue, but the gases will go in what it was describe to me as a maze of gaps in the boiler so it can extract as much of the heat that is possible a combi boiler is even worse since the gap is even smaller so it heats up quicker the biggest problem with combi's is they clog up much quicker and the crud in the water builds up inside of the boiler if it isn't flushed out on a regular basis.

 

I might just keep you to that, I think she is a 2 -6-0 if that helps

 

1000 gallons of water is 4 1/2 tons alone. I think your tender might tip the scales nearer the 9-10 ton mark

 

8 years is hardly a very long time when speaking about a new build loco, especially one that has been effectively redesigned to incorporate efficiency improvements.
Again, I would caution against the constant hinting about locos going to the L&B, without having spoken to the management there first.

Keith

 

8 years is perfectly reasonable for a new build. Especially compared with the 39 years I personally waited to see Lyn. Someone somewhere must have waited 80 years...

 

Agree completely with @ross on this one.

8 years from "OK, it's official - let's do it", through scoping*, researching*, design*, approvals*, materials sourcing*, tooling up*, production*, machining*, assembly*, quality compliance testing*, more ruddy paperwork*, steam testing*, painting & finishing*, running-in testing*, final adjustment* and final testing*, to handover actually isn't bad going at all.

All things considered, Stratford's 1891 record of 9h 57m for assembling a Y14 (LNER J15) 0-6-0 from components laid out ready for a crack specialist team, who'd worked on the self-same design umpteen times before over the preceeding 8 years, isn't exactly comparable is it? .... And not just 'cos the Stratford record involved only one coat of paint!

I'd describe this complex project as a triumph for all concerned.

* [at every stage add] fundraising & publicity, followed by more publicity & fundraising

 

Your a young whipper snapper at that age I have just turned 59 and some how have now got two projects to do stuff for.

 

The application had nothing to do with top feed and trays or water treatment, which is what you are suggesting. It was all to do with boiler performance. Top feed with trays are fine in soft water areas but are otherwise a total pain. The trays fill with "scale" in pretty quick order. That is why the French went away from them in the late 20s, Stanier tried them on the LMS and discarded them and was one reason the French realised they needed to get on top of water treatment, leading to TIA. Top feed is good at driving off oxygen delivered with feedwater but appropriate boiler water chemistry can do an equivalent job. Ultimately (outside of the UK) plenty of railways found submerged feed was fine.

 

Thanks for clarification. I was considering the heating effect of water fed onto a scale tray, a comment I read (somewhere or other!) claimed these trays were easily cleaned. I've no real handle on the rate of scale formation (in hard water areas) on anything much larger than a domestic kettle and certainly not a loco boiler!

The argument against submerged feeds IIRC was one of thermal stress immediately around the feed point, which (please correct this if it's garbage) was one factor in the short boiler lives apparent from historic records. Comments such as those made by an independant inspector into affairs at Tralee suggest that, in the case of less well run minor railways, it wasn't the only factor (original T&D 0-4-2t No.4 pretty much died of neglect inside 15 years, though not actually cut up until 1907).

Attempting to separate issues into water treatment and feed temperature, is there any published data on the Chapelon economiser which indicates it's effectiveness? My reason for asking is that it appears a straightforward 'passive' adaptation, certainly when compared with most other 'pre-heating' applications. Many proposed "improvements to efficiency" look great on paper, but come with an increase in complexity and maintenance costs out of all proportion to any benefits.

The classic example in rail terms has to be condensing locos, where the only successful application I'm aware of was the SAR/ZASM Class 25, where the driving imperative was scarcity of water supply rather than fuel saving. Even then, it took many broken condensor fan blades before they ironed out the problems. The size of tender required may mitigate against the S.African solution.

 

Reading the book about the Brighton 4-4-2's it seems that the LBSCR had some sort of condensing system, certainly in the 4-4-2 tanks, I have no idea exactly what.

 

Scale formation in top feed trays is a function of the specific water type so it is hard to be very specific. But it was bad enough in fleet service for various French systems to get fed up with it. After trays the LMS (and BR Standards) got angled delivery trays which, in theory, scale doesn't stick to but does distribute feedwater around rather than dumping it in one area. Not a bad system at all if you want to have top feed. On later Castle boilers an extra mudhole (or was it 2, can't remember right now) was fitted in front of the safety valve bonnet to facilitate easier cleaning of the trays.

I claim no knowledge of boiler life being short due to submerged feed but would offer a suggestion, was it the application of the submerged feed which caused the problem or the very nature of all submerged feeds? I know which I suspect!

 

No. I'm 46 but I was 7 when I discovered the L&B in a book at school.

 

Funny that, I was about the same age when I discovered Narrow Gauge Railways, I am sure it was the L&BR but not long after that my local library had a number of David and Charles books out on display and I recall borrowing both the Donegal and Lough Swilly books at the same time, I also worked out that I had just missed seeing both of them working by about 6 years, mind you didn't think about going to Waterloo to see the Bullied Pacific's at that time.

 

I appreciate that 15" gauge is an area for debate, some see it as miniature and others narrow but development continues on this gauge. Nigel Day is incorporating a significant number of improvements into "River Esk" and this locomotive is coming to the end of the protracted overhaul brought about by the arson attack on the R & E R workshops.

The late Phil Girdlestone was working on an advanced 2' gauge (definitely narrow - no debate there) 2-6-0 and the chassis for this engine is in the U.K. It is a rolling chassis complete with smokebox and exhaust system. It deserves completing and some interest is being expressed in doing this. This one should be well worth watching.