BR Standard class - practice and performance

They were repainted by the GWR (perhaps at Machynlleth) but in what appeared to be carriage brown.

 

Not sure. The SG goods yard at Mach stayed open of course (BR lorries handled remaining goods in the Dulas Valley after NG services succumbed) and from photographic evidence, several of the remaining staff were getting quite long in the tooth by closure in 1948. A few rail operations by the slate companies north of Aberllefenni continued, using a tractor straddling running lines, until the early 1970's. The Corris mainline was lifted within a couple of years of closure. The bridge rail of the Upper Corris branch (moribund since the only significant customer, Braichgoch quarry, began using it's own lorries following an increase in GW carriage rates in 1927) vanished in a scrap drive during WWII.

 

I can't suggest what a 2' gauge one would look like, but there is a proposal for a loco on line that gives a good idea what a 15" gauge Standard would look like:

http://www.steam-loco-design.co.uk/zb_article_6.html

John

 

2-6-2 or 2-8-2 would be more in keeping with a standard. But if it's turntabled at both ends of the line...

 

The page linked to above says "the absence of trailing non-coupled wheels avoids the transfer of weight from the driving wheels that occurs when pulling hard thus ensuring that the locomotive is less likely to slip." That makes sense only when the loco runs chimney first, so presumably that is the intention.

 

Interested in a great drawing of the Britannia class? You might have the opportunity: https://www.ebay.co.uk/itm/BR-Britt...884042?hash=item444fb2a5ca:g:yTEAAOSwKdNdkiXz

Knut

 

I have had some further thoughts about the BR Standards and would like to revive this thread. There has been discussion here and elsewhere about the benefits or otherwise of improving the power output of engines with Kylchap blastpipes etc. The BR Standards have been criticised for conservative design - but on the other hand some have claimed that increased power could have adversely affected reliability, frame life etc.

Consider the following: increasing boiler pressure increases maximum piston thrusts, which can certainly cause problems but if maximum steam output is increased without increasing boiler pressure, this increases maximum power output at speed (when piston thrusts are lower) but tractive effort and maximum piston thrusts are unchanged. BR locomotives which were improved in this way included the fitting of Kylchaps to A4s and the fitting of optimised double chimneys to Castles and Kings.

The experience of the BR Class 4MT 4-6-0 is strong evidence of untapped potential in the BR Standard locomotives. In response to a request by BR Southern Region for increased power, the Class 4MT locomotives were fitted with double chimneys, tuned up on the Rugby test plant. This increased the maximum steam production from 19,600 lb/hr to 22,490 lb/hr. In service, these engines were considered to be almost the equals of Class 5Mts, which had maximum steam production of 24,000 lb/hr. There is little doubt that with a more advanced blastpipe design (such as Kylchap or Koopmans) the Class 4MT could have fully matched the performance of a Standard Class 5MT.

This leads inevitably to some 'what if?' conclusions.

* It is almost certain that performance of the Class 5MT 4-6-0 could have been similarly boosted. It had a bigger firebox and boiler, so it is reasonable to assume that its maximum power could be similarly increased by optimised draughting - maximum tractive effort would be unchanged but a 20% increase in maximum steam production would give power at speed comparable to Class 6 locomotives such as Jubilees. Again, if the boiler pressure was kept at 225psi reliability should not be a problem.

* The combination of 'Super 4MTs' with Class 5 power and 'Super 5MTs' with class 6 power - and both with excellent route availability - would have been very useful all across the network, probably making the Clan Class 6MT 4-6-2 unnecessary.

* Similarly it is reasonable to assume that with optimised draughting the Britannia Class 7MT locomotives could have achieved nearly Class 8 power at speed, making the Class 8P Duke of Gloucester unnecessary.

It is hard to escape the conclusion that the BR Standards were practical, useful engines but with optimised draughting they could have been significantly better, with improved operating efficiency and fewer locomotive classes required.

Just a thought.

 

Possibly. But bear in mind that double chimney doesn't always equal improved performance - remember the Ivatt 4MT Moguls were initially built with double chimneys, weren't particularly good steamers, and then when re-fitted with improved draughting and single chimney, their steaming and performance massively improved

 

None of what you have said is fundamentally wrong. The only qualification I would make is with regards to wear and tear. It is not simply a question of maximum force but also duration and speed. The greater steaming rate can be used in two ways; either to pull the same load at higher speeds or pull a heavier load at the same speed. Both would increase wear and tear as there has been no increase in bearing surfaces, etc.

 

I think this is, as others have said, you "could", but would you. Riddles' design philosophies were:
Make it steam easily (to give margin for poor coal, unskilled enginemen etc)
Make it easy to maintain
Make it have a unified feel (ie use design cues from all regions)
I think there was also an unstated "get them out quick so I go down in history as a CME with a list of engines to my name before they change the rules again"
Would a kylchap etc system meet that? I don't really see that it does.

Had the BTC stuck with the slow paced steam to majority electric change, thus giving more incentive to develop and re-skill (assuming they could beat the labour shortages), and sort out the coal issue, then possibly.

 

BR Standard steam locomotives did not bring any technological advances, in many ways they were a retrograde step back compared with pre BR locomotives. Certainly in terms of coal and water consumption compared with the better locos of the Big 4.

What BR Standard did bring, was nicer cabs for the driver and fireman.
The UK had a labour shortage in the late 1940s, the railway was having difficulty recruiting and retaining skilled staff.
Whether the nicer cabs of BR Standards made any drivers or fireman stay, is hard to measure.

 

Its easy enough to pick out that the design brief behind standards was to give each class the maximum boiler, with an appropriate grate area, that its potential route availability/loading gauge would allow.
The thinking being that they would never be short of steam, and that boilers ' ticking over' are more efficient than boilers being 'thrashed', but also that the potential for thrashing was there.
Co incidentally work at Swindon on getting draughting proportions right was coming up with good results to the effect that the current thinking was a correctly proportioned single arrangement would in most circumstances improve upon an off the shelf/finger in the air arrangement be that single/double/complex whatever; a philosophy that even to this day has not been given due consideration. They also figured out that a correctly proportioned double could be a better solution if circumstances demand it; the preliminary design of a double chimney for a Standard 5 does actually exist... Unfortunately the penny dropped at a time more pennies for steam development were no longer forthcoming. The standards are in many cases remarkably good considering they were prototypes produced en masse straight from the drawing board and with hindsight its easy and fun to come up with 'mk2' standrds
My own would be a 3 cylinder caprotti brit, double chimney.
and a standard 6 2-8-2 mixed traffic...

 

A matter of opinion, and not one shared by all enginemen (Yes, I've read Terry Essery and he's definitely one on his own!). They could be draughty and dirty with coal dust swirling around, steam pipes were moved outside which made them cooler in summer; the alternative of course was that they were colder in winter. Nor was the 'meat slicer' reversing wheel universally popular, it was awkward and could be very stiff. They had their fans among enginemen, but . . .

A major problem was that enginemen expected a performance improvement from a new engine, but they weren't designed to provide this, and didn't. There was nothing a BR Standard Five could do that a Black Five couldn't, so enginemen generally couldn't see the point.

 

Increasing the maximum power output from any given size of loco is arguably of little benefit if you are going to build a range of sizes anyway. But better draughting could have improved efficiency for any given power output, thus reducing the amount of shovelling required.

 

I understand that the reason for the reverser orientation was that a push-pull movement is easier than a sideways one. If they nevertheless were hard to operate, that suggests something wrong with the detailed design rather than with the principle.

 

Except it wasn't just push-pull, there was a vertical component involved in the movement. Whatever the reason, many men weren't happy with it.

 

Which probably explains why the Brits were viewed as they were on the GE vs the GW and why the twenty class fives the Southern got were well regarded--- they were a definite upgrade on the superannuated locos they were replacing.

Presumably there was a lot of railway politics in the allocation between regions? The GW had to have some even though they didn't really want them.

 

I've had the pleasure to have driven 55 ex BR locos, 10 of which were BR Standards of 5 different classes. All I can say is that, for me as a driver wanting an easy life, give me a Standard any day. Even more so if it is a Cl.4 tank. As far as I'm concerend the only thing they got wrong with those was the shovelling plate. Never had any problems with steaming and the class 4's of all versions were always up to the job on the NYMR (7-8 coaches).
With regard to the meat slicer, I like them although I agree that they can be stiff when ex works. It doesn't tend to last, though. They come into their own when running in reverse. Unlike a lot of people, I sit facing into the cab with my head turned to the right as they are meant to be driven and not all twisted with my head out of the window.

 

To my mind the problem with the standards was complacency. You can see it in Cox' books. He seems quite convinced that steam locomotive design had reached optimum performance, and there was no advance to be made on late LMS practice.

 

To be fair, Steve, you're not really comparing like with like: you're talking preservation while I'm talking about opinions of drivers in BR service. I wasn't - quite - there myself but was a guard from the early 1970s, less than five years after steam finished, and worked and talked with the men who had worked steam in the 1960s, 1950s, 1940s and earlier. The opinions stated were theirs, although I've probably adopted them since.

Today, almost all trains you work are passenger trains, fully fitted. Back then the majority would have been loose-coupled or part fitted. You have a speed limit of 25 m.p.h., no admissions but probably nearer 35, while back then 60 would have been common, sometimes even with a loose coupled goods. The engines you drive are clean while back then, filthy. It might seem inconsequential but there is a psychological element on climbing on to a filthy footplate. Defects might be deferred for three or four weeks to the next washout or X Day. That still happens but the mileage covered with those defects would be much greater. It's the SVR that I know and a normal day might consist of 64 miles. A gala might take this to 96, but that would last two, three or possibly four days. On BR, that would be normal and often exceeded, and this for most days in the fours weeks to the X Day.

Opinions varied and I recall some discussions, even among the men at Edge Hill, and the wider the net, the greater the difference of opinion. The Britannias were loved on the Great Eastern but hated on the Great Western. GE crews had gone from Class 4 B12s through Class 5 B1s to Class 7 Brits in less than ten years, so they were bound to be pleased, while GWR crews were faced with either a Castle or a Brit and knew which they preferred.

9Fs are generally thought by the enthusiast to be wonderful things but it wasn't an opinion shared by the men I knew. To be fair, they weren't too common north of the Mersey but Birkenhead had quite a few. But instead of the fast, fully fitted block trains they would have excelled on were working turn and turn about with 8Fs (and O1s/O2s, 28xx, etc.) and frankly the eight-coupled engines were better at it. With a heavy unfitted mineral train, the ability to pull was secondary to the ability to stop, and 9Fs were not renowned for the braking power.

The general opinion of the BR Standards was that they were alright but nothing to write home about: If I'm to take a Class Five engine give me a 'Black 'un' rather than a 73xxx.