New-Build Steam Locos

[LMS2968]

6202 was indeed based on an existing design; this was one of its weaknesses but necessary for comparison purposes. It therefore was built with six coupled wheels of 6' 6" diameter, needed with the Lizzies for the speed with reciprocating drive; the Turbo could have been built with more numerous but smaller wheels since wheel rpm would not have been an issue.

 

There were several turbine drive attempts after 6202, mostly in America where the turbine drove a generator which in turn drove traction motors on bogies each end. This 'Power Station on Wheels' scenario basically took standard diesel technology but replaced the engine. Since it was replaced with a boiler, turbine and, ideally, a condenser, the results were very big and very heavy. Read all about it in 'The LMS Turbomotive'* by Jeremy Clements and Kevin Robertson (2016) Crecy Publishing, Manchester ISBN 978-1-9093-2852-5.

 

*Despite the title, it covers all the turbine engines, and well worth a read.

[LMS2968]

1 hour ago, Pete the Elaner said:

It would be interesting to free ourselves of the bias of following 'what we know' & design something from the ground up.

 

The question that must be asked here is, "For what purpose?" No matter how successful your design-from-scratch might prove, it isn't going the displace diesel and, even more so, electric as the motive power for any of the 'normal' TOCs; there's too much investment in what's there already plus the necessary new infrastructure of, say, watering facilities, and stopping to take water won't be at all popular anyway. The alternative of a condensing plant will add massively to size and weight. If you are looking only at the railtour market for the enthusiast (although not all participants fall into that category) you have something at the front end which lacks the appeal of history and nostalgia.

 

Sorry, but steam is dead as far as major development goes. I hate saying it, but that's how it is.

[Reorte]

1 minute ago, LMS2968 said:

The question that must be asked here is, "For what purpose?" No matter how successful your design-from-scratch might prove, it isn't going the displace diesel and, even more so, electric as the motive power for any of the 'normal' TOCs; there's too much investment in what's there already plus the necessary new infrastructure of, say, watering facilities, and stopping to take water won't be at all popular anyway. The alternative of a condensing plant will add massively to size and weight. If you are looking only at the railtour market for the enthusiast (although not all participants fall into that category) you have something at the front end which lacks the appeal of history and nostalgia.

 

Sorry, but steam is dead as far as major development goes. I hate saying it, but that's how it is.

 

Just for the interest in doing so! I don't think anyone is seriously suggesting trying to compete on a practical basis to replace diesel and electric.

[Nova Scotian]

7 minutes ago, Reorte said:

 

Just for the interest in doing so! I don't think anyone is seriously suggesting trying to compete on a practical basis to replace diesel and electric.

Interesting thought exercise then for the new build enthusiast crowd - does it need to:

1. Look like a steam loco

2. Look like a specific steam loco

3. Sound like a steam loco

4. Smell like a steam loco

 

Current new build suggests all four is important.

 

Rebuilding turbomotive would hit #1, #2, and #4 (how many of us heard turbomotive? Not me...)

 

Switching off coal would remove #4 and alter #1, #2 possibly.

 

New design, reciprocating would hit #3 and #4.

 

I don't think we'll see any new designs - we'll see continuations of families of locos where they're filling in gaps, or in time replacing as preserved are withdrawn.

 

[Reorte]

New build to an old design (even with some alterations to fit the current railway) also has the advantage of having some idea of its performance, although I'd expect modern modelling to be able to answer that question pretty well before anything is actually built physically.

 

Personally I'd probably end up going with all four of your points because at the end of the day it's really (to me) about something I simply love the whole look and feel of, but any approach makes for an interesting discussion at the very least.

[Pandora]

I have thought  the time will arrive when  a clean sheet design of Standard steam loco optimised for the operational needs of a  heritage railway will be proposed, probably a 2-6-2T or a 2-6-4T, parallel boiler for ease of construction, deep and narrow firebox and long boiler  for economy of coal use  in the stop start / layover situations of the typical preserved railway . Tractive effort / driving wheel diameter to be decided, any suggestions?

Edited March 9, 2020 by Pandora

[LMS2968]

31 minutes ago, Pandora said:

I have thought  the time will arrive when  a clean sheet design of Standard steam loco optimised for the operational needs of a  heritage railway will be proposed, probably a 2-6-2T or a 2-6-4T, parallel boiler for ease of construction, deep and narrow firebox and long boiler  for economy of coal use  in the stop start / layover situations of the typical preserved railway . Tractive effort / driving wheel diameter to be decided, any suggestions?

So not a clean sheet! Basically it would be what in modelling terms is known as a freelance version of existing design criteria.

[PenrithBeacon]

I think the proposed Stanier 2-8-4T would ideal, but perhaps a saturated boiler would be more suitable for heritage lines.

[mdvle]

20 hours ago, Northmoor said:

As for the industry sustaining the new builds, it has to.  Continuously rebuilding 100 year-old locos can't go on for ever.  Remember that the last locos built for British Railways are now 60 years old; OK many of those spent more than half that time out of use, but that's just the newest locos. I can see locos like A4s increasingly being retired as it gets harder to write off £500-750K overhauls every ten years.

 

1) the benefit of steam locos is there is nothing "difficult" to make new - you don't have to try and keep old discontinued electronics working, or replace - it is all mechanical and just a matter of machining a new part(s).

 

2) new steam locos are very expensive - Prince of Wales P2 apparently in the £5 million range and the LNWR George the Fifth in the £2 million range - and after spending that money they will still need the 10 year or whatever overhauls.  And while their overhauls may well be cheaper, when you can get 30 years or more of overhauls for the cost of a new build...

[Pandora]

29 minutes ago, PenrithBeacon said:

I think the proposed Stanier 2-8-4T would ideal, but perhaps a saturated boiler would be more suitable for heritage lines.

Coal is not cheap to buy,   and I would be designing  for economy of coal consumption,  therefore superheating would be on my list of design parameters

Also perhaps a 4-4-4T wheel arrangement for free running and fewer  driving wheel axle boxes/driving wheel tyres to maintain

Edited March 9, 2020 by Pandora

[PenrithBeacon]

After a loco stops the superheated steam is discharged to atmosphere and the superheater cools. It takes time, once the engine is moving again to get the superheater back up to temperature, say about 15mins. This cycle costs in terms of fuel consumption and on most heritage lines superheating isn't worth it. There are exceptions.

[LMS2968]

If you were to run non-stop on the longer preserved lines, superheaters would become viable. But those railways don't work that way, so the benefit obtained is between small and none.

[Pete the Elaner]

6 hours ago, LMS2968 said:

The question that must be asked here is, "For what purpose?" No matter how successful your design-from-scratch might prove, it isn't going the displace diesel and, even more so, electric as the motive power for any of the 'normal' TOCs; there's too much investment in what's there already plus the necessary new infrastructure of, say, watering facilities, and stopping to take water won't be at all popular anyway. The alternative of a condensing plant will add massively to size and weight. If you are looking only at the railtour market for the enthusiast (although not all participants fall into that category) you have something at the front end which lacks the appeal of history and nostalgia.

 

Sorry, but steam is dead as far as major development goes. I hate saying it, but that's how it is.

I wasn't thinking specifically about steam power, but in general terms.

We were stuck with reciprocating steam because that is what engineers, maintenance & driving crews were familar with.

With road transport, we were until recently stuck with fossil fuels. Only recently has anyone made battery stored electric vehicles a practical alternative.

Maybe somebody will invent a way to transmit power to vehicles? If not, then a better way to store energy than in heavy batteries & cleaner than fossil fuels?

[Pete the Elaner]

4 hours ago, PenrithBeacon said:

After a loco stops the superheated steam is discharged to atmosphere and the superheater cools. It takes time, once the engine is moving again to get the superheater back up to temperature, say about 15mins. This cycle costs in terms of fuel consumption and on most heritage lines superheating isn't worth it. There are exceptions.

Is that the way superheating works or how it has been implemented in the past?

 

Taking it a step further would give you extra high pressure steam, which is more efficient when working. LMS tried this with 6399 Fury but the extra cost to maintain it cancelled out any efficiency advantage.

Killing an engineer when a pipe fractured highlighted the extra danger too.

[Dave John]

Steam needs heat. 

 

That means burning something or using electricity to heat water. Hmm. 

 

I don't wish to sound pessimistic but the way things are going the environmentalists intend to criminalise anyone that burns a slice of toast. 

 

Enjoy the last few years of preserved steam, I suspect that no matter how efficient any "new" design is it will just get banned to fullfill political tickboxes. 

[Nova Scotian]

7 hours ago, Pandora said:

 design of Standard steam loco .... Tractive effort / driving wheel diameter to be decided, any suggestions?

This is a great idea. However, we need to meet the needs of differing heritage railways and enthusiast tours.

 

So let's suggest some designs, of, let's call them "Standard Classes".

 

We can have a mix of driving wheel diameters, boilers, tractive effort, power ratings, and even a mix of tender versus tank.

 

However, for economies of scale they should probably use a common cab layout and shared components.

 

We could name them based on their tractive effort. This, new, class of standard locomotives.

 

The name Sir, is Riddles. Mr Riddles.

[Pandora]

8 hours ago, PenrithBeacon said:

After a loco stops the superheated steam is discharged to atmosphere and the superheater cools. It takes time, once the engine is moving again to get the superheater back up to temperature, say about 15mins. This cycle costs in terms of fuel consumption and on most heritage lines superheating isn't worth it. There are exceptions.

I read up that an exception is when  saturated steam causes a scouring action to the cylinder liners reducing their service life,  by superheating the  steam there is  a benefit of less of the scouring activity,    point taken as to the time delay before the superheater heater circuit  to reach working temperature

[Pandora]

3 hours ago, Nova Scotian said:

This is a great idea. However, we need to meet the needs of differing heritage railways and enthusiast tours.

 

So let's suggest some designs, of, let's call them "Standard Classes".

 

We can have a mix of driving wheel diameters, boilers, tractive effort, power ratings, and even a mix of tender versus tank.

 

However, for economies of scale they should probably use a common cab layout and shared components.

 

We could name them based on their tractive effort. This, new, class of standard locomotives.

 

The name Sir, is Riddles. Mr Riddles.

Yes, but the Standards had taper boilers, expensive to construct, and were also biased towards LMS  thinking,   to the exclusion of other railways,  a simple Thompson parallel  boiler,  would that be a starter point?,  A 4-4-4T loco is the gap in British steam history. it isnot about displacement, but giving  60-100 year old veteran locos an easier time to further extend their operational life,  many years ago, I heard  retired ex Works steam  men talking on the subject,  a simple to operate but modern steam loco to swell the ranks  of the heritage railway fleet

Edited March 10, 2020 by Pandora

[Joseph_Pestell]

3 hours ago, Pandora said:

A 4-4-4T loco is the gap in British steam history. 

 

You mean in terms of none preserved?

 

Is wheel arrangement enough in itself to justify preservation / new-build? I have doubts. But if it were to be done, the Met Rly 4-4-4T would be my choice on the grounds that the Met is under-represented in preservation.

[Pete the Elaner]

4 hours ago, Pandora said:

Yes, but the Standards had taper boilers, expensive to construct, and were also biased towards LMS  thinking,   to the exclusion of other railways,  a simple Thompson parallel  boiler,  would that be a starter point?,  A 4-4-4T loco is the gap in British steam history. it isnot about displacement, but giving  60-100 year old veteran locos an easier time to further extend their operational life,  many years ago, I heard  retired ex Works steam  men talking on the subject,  a simple to operate but modern steam loco to swell the ranks  of the heritage railway fleet

There is a very good reason for Riddles' LMS bias: Stanier.

Without going into too much detail, Stanier was the best mechanical engineer of his generation.

This was the opinion of the country's most senior & respected mechanical engineers, who awarded him the prestigious title of FRS (Fellow of the Royal Society).

 

So Riddles learned from the best. Is it a surprise he used this knowledge & experience when designing new locos?

 

Taper boilers were something Stanier introduced to the LMS because they out-performed parallel ones.

 

[tomparryharry]

2 hours ago, Joseph_Pestell said:

 

You mean in terms of none preserved?

 

Is wheel arrangement enough in itself to justify preservation / new-build? I have doubts. But if it were to be done, the Met Rly 4-4-4T would be my choice on the grounds that the Met is under-represented in preservation.

 

The Midland & South Western had some 4-4-4 tank locomotives. If its preservation, then something that's simple, standard, and hard to break. Funny enough, an 18" Austerity with 4'6" wheels, slightly larger boiler/firebox set up, would be a vast improvement on an original 18" Austerity. 

 

Before you start having new locomotives, you'll need to actually teach those locomotive crews how to operate said locomotives. The skills gap is enormous, and grows exponentially year on year.  The wise way to repair a steam locomotive, is not to break 'em in the first place......

[tomparryharry]

9 hours ago, Dave John said:

 

 

I don't wish to sound pessimistic but the way things are going the environmentalists intend to criminalise anyone that burns a slice of toast. 

 

 

 

That's me bu66ered, then.....

[Dr Gerbil-Fritters]

On 08/03/2020 at 16:09, LMS2968 said:

I'd suggest that the starting point in any new design is the type of fuel.

 

What could possibly go wrong?

 

[Hroth]

11 minutes ago, Dr Gerbil-Fritters said:

 

What could possibly go wrong?

 

 

The crew and the passengers in the leading coach get out looking like Readybrek Kids?

 

Could be useful during the winter, I suppose...

 

[Hroth]

8 hours ago, Pandora said:

Yes, but the Standards had taper boilers, expensive to construct, and were also biased towards LMS  thinking

 

Not quite "LMS thinking".

 

As mentioned above, Stanier brought the tapered boiler to the LMS, at a time when they were still wedded to the parallel boiler. And where did Stanier get the tapered boiler from? From where HE was trained, the GWR, where Churchward developed his "standard" tapered boilers for his carefully considered standard classes of locomotives in the early 1900s.

 

Its all costs and benefits.  A tapered boiler might be initially more expensive/complex to construct but it will return that cost considerably in savings over its working lifetime.