O.V.S.Bulleid - The Southern Enigma

If anyone thinks the Thompson L1s were bad, you should look at the mileages and availability the production models had, and how long lived they were in the context of the modernisation scheme (or, conversely, go read the Thompson thread and discover that the secondary evidence is a load of rubbish).

 

With respect Jim, its what I have been saying about the Thompson story on this forum since 2012, the literal equivalent to banging my head against a brick wall repeatedly for over a decade.

 

I think that L1s were unsuited to their intended work, rather than bad, the wheels were too small which caused rapid wear of axleboxes and the motion.

Another rule of Nat Pres, mention of L1s sparks controversy!!

Anyway, back to the Leader, are we agreed it was a dead loss?

 

Please read my book. That’s been thoroughly debunked over, and over, and over again…

Kevin Robertson’s latest version of his book has almost convinced me it was worth pursuing, but the sleeve valves were junk, IMO, and a ridiculous additional complication it didn’t.

 

I will get round to reading it some time, yes.

agree on sleeve valves, they could give trouble in their other applications in aircraft engines and high end cars like Daimlers, which would get very careful maintenance in clean surroundings, so why it was thought they would be ok in the dirty environment of a steam running shed is a mystery.

interestingly, the Irish development, the CC1,didn't have them and was marginally better

 

Sleeve valves were very good for commercial aero piston engines, but were overtaken by jet engines, the Bristol engines time between overhaul was much better than conventional poppet valves.

It's not really a good idea to extrapolate car (Knight twin sleeve) or aero (Burt-McCollum single sleeve) ICE experience to steam use though, as very different in application, although clearly the latter was influential in the addition to leader of the rotary motion of the sleeves of leader to make them oscillate to obtain the unbroken oil film benefits.

I can't seem to find the video showing them in operation now, or even any sketches, but seem to recall they were somewhat similar to having piston valve gear encasing the power pistons, which obviously saves a lot of space, and reduced dead space leading to greater efficiency.

 

I think we need to include EMUs to get a full picture of the motive power designed and built under Bulleid. From a quick totting-up of numbers from an Ian Allan abc, I think around 100 new 4-SUB units were built in the 1941-49 period. In the subsequent 1950-57 period, the Southern Region fitted new Bulleid-type bodies to several hundred older EMUs (which previously had pre-grouping wooden bodies on 1920s Maunsell underframes).

Due to the large-scale building of 2-10-0s in WW2, Germany and much of Europe was almost awash with them -they were the most numerous types in several countries (In France, 2-8-2s became dominant). In contrast to Britain, and in spite of wartime losses, the Continental European railways do not seem to have built many new small steam locos after WW2. That would have been partly due to electrification and diesel railcars arriving more quickly than in Britain, but also, as you say, using available large steam locos for minor jobs (rather like on today's heritage railways). Britain (more particularly the LMS & GWR) seems to be very much the exception in continuing after 1945 to build large numbers of small 2MT/3MT and pannier tank types.

In Britain early post-WW2 electrification was limited to completing the LNER projects for the Woodhead route and GE suburban lines. But Bulleid may well have expected early moves to re-start the SR electrification programme, so would have been planning with that in mind. So the SR situation was in some ways more akin to that of Continental railways rather than the other British regions.

 

At risk of dragging the subject well off-topic, I too had come round to the opinion that Bristol got their sleeve valve radials working pretty well and maybe they were a good idea.

However, on reading "The Secret Horsepower Race" by Calum Douglas (an excellent work in many ways, and an exemplar of how to revisit a much-covered subject with the benefits of broader sources and genuine technical expertise), he made the very valid point that the opportunity cost of the sleeve valves was not justified (paraphrasing). In the time that Bristol spent making sleeve valves work reliably, they lost their lead in supercharging, which was one of the most important performance drivers for a WW2 aero engine. They went from having a pretty good poppet valve radial and the best superchargers, to having finally made the sleeve valves reliable and having adequate superchargers in a field that had moved on, while everyone else went over to sodium cooled exhaust valves and cured their detonation problems that way.

 

Very true I think. I imagine, what with increased availability etc, it must have been something like four 4-Subs replacing six small or three large steam engines. Perhaps a Southern specialist could give us better numbers?

 

I would have said the 4 SUBs nearly all replaced earlier emus rather than steam, a lot of trailers being built to strengthen the old 3 SUBs in the 43xx and 45xx series. Was there any electrification post war before the Kent Coast? Possibly Swanley to Sevenoaks and Maidstone East? There is a website called Bloodandcustard with lots of info about the emus.

Edit---no, Maidstone E was done in 1939.

 

Bulleids emus were very good, the BR built 4EPB derivative lasted long enough to run for Network South East

 

And the americans supplied petrol with so much brain damaging lead that octane rating was 135 running lean and 150 during maxpower where fuel to air ratio was double the stochiometric.
Germans were very low on lead and used aromatics (Benzene) that is a proven carciogenic.

Bulleid can hardly have avoided contact with the firm of Riccardo and they had something very special sleeve valves working.
Bristol had sealing rings between piston and sleeve and between sleeve and cylinder head.

Riccardo had found that sleeve did not need the last mentioned rings.
During start and running up the sleeve grew until gap between sleeve and watercooled stationary parts was so narrow that heat comming in got out at same rate.
Very elegant and tempting for a playboy like Bulleid.
That can have been the secret behind lots of visible steam from the Leader.

 

Sleeve valves have been discussed on NP before.

The conclusion was that they are excessively troublesome especially in a steam loco.

On trials against a Mogul leader managed 1% thermal efficency against the Moguls 4%.

David Wardale managed 15% with the SAR Class 26 which is a pure 'Stevenson' locomotive.

Clearly there was a significant potential to improve the performance of existing loco's or design something like a BR Standard with 'all mod cons; rather than go down the Leader route.

 

He was given a Brighton Atlantic, 32039, to test the sleeve valves on. How did that show up in trials?

 

I don’t think Bulleid was especially interested in thermal efficiency. If you look at his designs, he focused on (1) labour saving for crews and (2), related, high utilisation (i.e. reduce servicing times and therefore aim for more hours productive per day).

He wasn’t necessarily successful in everything he tried, but if you are judging him, it should be against what he tried to do. Labour was more expensive than coal, so I don’t think he should be criticised for trying to cut the amount of labour involved in operating steam locos. Thermal efficiency was not the objective.

Tom

 

Firstly I wont disagree in one extent BUT as David Wardale pointed out the low thermal efficiency of the steam loco imposed a cost not only in coal but hauling it to engine sheds, handling and getting rid of the ash

 

The only electrification post WWII and pre Kent stage I AFAIK was the short link
into the Harbour station at Newhaven in 1949, thus allowing an electric loco to
haul the Newhaven Boat Trains ( one of the three “ Hornbies “.)
Steam continued, WC/BB 4-6-2 were permitted to enter the Harbour Station from 7/1951,
to haul ‘reliefs’ into the early Sixties. There were also periods when no electric
locos were available. The Bricklayer’s Arms crews took up the challenge of maintaining
the electric 70 minute Down, 73.25 mins UP schedules with 500 ton plus trains and
BB/WC 4-6-2s. There was one period when the subsequent outbreak of line-side fires
induced an easing of the schedule. Before the easing 34045 had maintained the UP
timing. From Keymer Jct , passed at 20mph ( not 70 if from Brighton) it maintained
the Brighton 60 minute non stop timing.

Michael Rowe

 

Tom. Are you sure about this? I recognise that OVSB in his 1945 address concentrated on mechanical
aspects, but he was speaking to the I.Mech.Eng. I am fortunate to have his copy of Chapelon’s 1938 ‘La
Locomotive a Vapeur”, which includes a hand written note in OVSB’s writing on C.I.E note paper. I
mention this because I have always understood that he was influenced by Chapelon ( They knew
each other well I believe, certainly Bulleid accompanied the LNER P2 on its visit to France and
Chapelon was involved in the Test programme ). Thermal efficiency was very much at the forefront
of French developments. ( the limitations imposed by the second Law of Thermodynamics ). Coal,
despite Chislet and Tilmanstone, was a relatively more expensive commodity on the SR than
North of the Thames,

Presumably Bulleid always had oil firing in mind ( the original intention for the Leader ? ) but
post WWII , with sterling under threat, coal was to be preferred.

Michael Rowe

 

Assuming the Southern had carried on, and that Leader couldn't be made to work, I wonder how they'd fill the light-axle load/shunting/other duties a bullied pacific couldn't do? More Q1s? Bought Fairburn tanks from the LMS?

 

I cannot imagine Bulleid buying anything in, so if he was still CME it would surely be an in house design. The trouble is they would have been under extreme time pressure. Basically an N class chassis perhaps, with a Bulleid designed boiler into either a 2-6-2 or 2-6-4? But effectively recreating the K class would be problematic. Alternatively can we imagine Bulleid gets the elbow after too many failures and Holcroft is given a night watchman role while they look for a new CME? I could imagine Holcroft using as many N1 bits as possible, notably outside cylinders and motion in a slightly smaller and very Churchward influenced 2 cylinder 2-6-2T, but there seems no choice but a new boiler for a lighter axle load locomotive.