Steam loco development in the 21st Century

Updated 6202 Turbomotive.

 

An updated and crucially 'fixed' Leader. Oil fired maybe

 

Well, I'll concede that bogies have got to be a better bet in terms of a vehicle so the principle of the Leader is right in that respect. The next question to ponder is whether the conventional Churchward/Player boiler should be perpetuated or whether another form of steam generator should be considered. The conventional boiler has the advantage of providing energy storage allowing short levels of high output but do we really need this? Automating a conventional boiler is not going to be simple and we really need to get down to one-man operation. Along with this must go a decision on the fuel to be used. Oil firing ought only to be considered if the concept allows its energy to be used at less cost than in a conventional diesel.
I personally think that Bulleids bogies with the cylinders being part of them is fundamentally wrong and that the cylinders should be mounted on the mainframe with a cardan shaft drive or similar. (Do we discount electric transmission and stay purely mechanical?) By doing this we do not have to worry about relative movement of cylinders and axles and can thus better seal and lubricate the prime mover.

 

I think that for main line steam to survive there is a need for development of a sort. I think the 5AT project tries to get the focus of too much finance in an environment where the available money tends to spread quite wide, (ie a number of different classes with their own supporters). But I said the A1 project wouldn't succeed, so what do I know!

I'm not an engineer so won't go into technical developments. Others can do that. I'll stick to those I see as needed just to keep steam on the main line. They are really all fairly superficial, except for the cost of implementing them!

Oil firing. A change because the modern railway will increasingly abhor even a low risk of lineside fires.

Reduced hammer blow, (as I believe is the case with 60163), to eliminate some speed restrictions and therefore make pathing easier.

Slight changes in loco profiles. Again to eliminate some speed restrictions for pathing reasons. I'm talking small protuberances here, like handles etc.

Larger water capacity tenders. Again for pathing and operational reasons.

I don't know enough about the FTR etc regime to be able to say what development is needed to raise speed limits for individual locos. But I see that as another pressure on loco operators to keep running steam on the fast main lines in future decades.

The above could all be seen as fairly superficial in terms of steam loco development. They don't see much change at all in the design and operation of the existing fleet. Maybe it's just a list of the sort of costs that owners may have to face up to keep existing machines running on the faster main lines as this century progresses. It will inevitably, rather obviously and somewhat sadly see a reduction in the main line steam fleet.

 

On the boiler design, if we stick with the fire tube type, there are ways efficiency can be improved. The Crosti boiler did not prove a good solution at the time, but could it be improved, given time and money? What about tube inserts to increase turbulence in the exhaust gas, but take a higher pressure drop. Then there is the twisted bundle, being used in some heat exchangers.
Materials of contruction have also changed over the years, are there any better available now for the service? There are many different nickel and chromium alloys now available. Can plastic be used for some of the construction (obviously not the hot stuff!) eg tender tank and fittings.
Are there now small water treatment packages (RO) that are portable and small enough to be fitted on board? - only required if regularly travelling where good quality treated water is not available.
Sorry, too many questions and no answers! I'll leave the experts to shoot these ideas down.

 

Generally I agree that it is as a heritage vehicle that the steam engine will operate therefore all else is speculation, but ...

A Garrett variation would be, for me, the way forward. The major issue would be the articulation for fast running - it took American engineers 25 years or so to develop the Mallet into a mixed traffic engine from a freight slogger, mostly because of design issues surrounding the Mallet articulation. So, I would articulate a Garrett by using the standard BR buckeye couplers instead of the Garrett design.

A 4-8-4+4-8-4T with 56" drivers; the centre bogies supporting the middle (boiler) assembly, the leading and trailing bogies and the coupled wheels under the the two outer trucks. The engine would have a cab at either end to enable fast running, be oil fired and have a water tube boiler. Preferably the engine would be turbine driven (at least 5K horses) because I don't like the idea of a reciprocating motion at a cruising speed of 125mph and I'd call it 'Lancashire Witch'.

Such an engine would be perfectly capable of hauling 14-16 Mk 3/4 coaches and fit in with the pathing of the mainline railway, and you just might get some change out of £10M!

Regards

 

Only issue with a garratt may be loading gauge...


For me I'm more interested on what fuels would be used. waste oil anyone?
Regards
Duncan

 

Why carry fuel? If you imagine enough water, why not use a form of immersion heater, and pick up from 3rd rail, or pantograph? Need to move away from large cylinders, as reciprocating mass & hammer blow can be engineered out. I'd imagine a turbine, with discharge into a condensor, via a pre-heat chamber for the main boiler. I'd also imagine bogies, with wheels around 3'6" (1,066mm).

Regards,
Ian.

 

Electronics haven't been mentioned but there's no reason why a modern steam loco couldn't have computer controlled valve timing for example to increase efficiency, and constant water softening sampling and adjustment.

Dave

 

Welcome to the thread, lets hope it turns out to be interesting an possibly even productive at the end.I see some very interesting debate already , You make some interesting points Steve..I agree with your view that the power unit should be within the main body using either direct drive I see possible problems with this as a very high torqe needs to be transmitted to the bogie through shaft joints, turning moments may create issues , "steam electric" with bogies with suspended DC traction motors, or even hydraulic positive displacement system would work.

 

Certainly systems which absorb as much of the energy in the fuel as can be, are a prime objective
.
however you have to consider that generating electricity is not a very efficient process, as the primary energy source.

 

Don't see the point of steam-electric or of bogies. The diesel-electric does that already and with far less complication. A steam engine has the only engineering virtue of simplicity, complicate it, as Bulleid did, at your peril.

The steam-electric requires a device to turn a generator (a steam turbine perhaps) to produce the electricity to turn electric motors. Eliminate the steam boiler and the turbine, replace with a diesel and at a stroke you have simplified the design and produced a machine that will work at a far greater degree of efficiency and simplicity. For steam to work it must be simple; it's its only virtue - apart that is from the aesthetic.

The 'Leader' was a daft concept, far too complex. I once met a bloke (a BR employee) who knew a fireman on the 'Leader'. I won't be permitted to repeat the Anglo-Saxon vernacular here, but it was most expressive.

Regards

 

It depends on what you want to achieve. What is the main duty to be carried out by the proposed design? No use in proposing a 6000hp compound expansion garratt if you are wanting to move 3 or 400 tons of passenger stock at 125mph. If you want an independant traction unit (a locomotive) then you have to carry your own fuel. Forget turbines, they have a very limited optimum band of rotation and dealing with the result of this can be a real PITA. Why choose oil firing? In the USA for every dollars spent on diesel by the railways approximately $6 is spent on defence expenditure to protect the supply of the crude. We too need to protect the supply, so what is the real impact of oil firing? Every £1 of tax revenue has what environmental impact? None? Some? It will be some but how much? This is an important question, Raisied the issue with my M.P. No answer received to my written question, but I should not be surprised. Taxation has an environmental impact the trouble is no one seems to want to quantify it.
As for new engines, keep them as small as possible. Compound expansion with high boiler pressures and steam temperatures. Mechanically follow best American practice.

 

You've spotted something that no one else has Steve. If this mythical loco is going to be used on NR, it is going to have to fit in with their wishes, and one of them is to minimise unsprung weight. I think an updated Leader, with computer controlled mechanical "firing", one man operation, and a cab at each end is the way to go. Bogies definitely, but the drive to them needs to be body mounted, a la Class 91, to reduce unsprung weight.

Do sleeve valves have a part to play? The optimum modern steam loco needs something more efficient that the traditional variety.

 

Dare I say it, a small nuclear locomotive... not aloud today but in say 2150 when oil has run out, C02 is under strict regulation and bio fuels are a no go. Electrification of all routes hasn't taken place and nuclear is 140 years more advanced. They may have even mastered nuclear fusion by then.

Leader had sleeve valves and they were a reason for so many failiures.

 

Which is exactly why I mentioned them. Many of the failings of the unmodified pacific locos, have been ironed out in preservation, essentially because modern materials can do what the designer intended, unlike those in post war Britain. Could a sleeve valve, engineered to 21st Cent. specs., provide the instantaneous valve events that Bulleid intended, with the desired level of reliability?

 

Dear oh dear, people,

Why do people ride behind a steam hauled train?
Why do people go out to the lineside to watcha steam hauled train go past?
Why do people volunteer their time to keep steam hauled trains as more than an arcane concept?

There is one answer to all three questions. The locomotives that do the actual hauling are preserved/reconstructed machines from the past. These locomotives have visual appeal, with a multitude of wheels, of varying diameters and exposed machinery. Additional visual appeal is given through the differing shapes that make the locomotive up, from the (almost) feminine curves of the boiler to the harder masculine angles of the cab, tender and/or tanks. They have aural appeal, the sound of each exhaust beat can be heard far & wide in optimum atmospheric conditions.

Some of these machines that you lot are advocating are far removed from this ideal. Why don't you dust off the drawings of the 'Jawn Henry' or the C & O steam-turbine-electrics?

Steam locomotives today are about entertainment and nostalgia, not hyper efficiency and multiple unit (diesel or electric) aesthetics.