Uk Push Pull Steam Workings/Steam Multiple Units & Buckeyes/Concepts

Afternoon Folks

I was having a flick through an old copy of the railway magazine last night & got to thinking - with the exception of the GWR autotrain that was apparently trialled on the brentford branch (according to wikipedia). Werre there any other attempts at the push/pull concept?

A couple of other things that came to mind were:

Steam Multiple Units (SMUs as I thought they could've maybe been called). The closest thing to a steam multiple unit I can think of is the steam railmotor that worked the looe specials. With more research & development etc, could the concept possibly have gone further??? The autotrains were kind of multiple units in a weird way as they had the loco sandwiched between 2 trailers.

Finally buckeye couplings - It's always baffled me why britain didn't follow the yanks with fitting steam locos with buckeyes. It surely would've saved the crews a fair amount of time farting about with screw couplings & somebody once said they believed buckeyes to be safer couplings but I don't buy into that myself.

Anybody got thoughts on the above, just a few concepts that've come to mind over the last few weeks or so. Does anyone else have any other possible concepts/ideas that were maybe thought up but never got off the drawing board that relate to the above?

 

I believe the LNER Pacifics with corrider tenders are fitted with Buckeye couplers could be wrong but I think they were the only ones fitted. As regards fitting them though you only have to look at things like vaccum brakes, unbraked freights etc. Why did it take so long to adopt them over here?

 

Not sure I really understand the question - push-pull trains were common right across the country in pre-preservation days. Or do you mean specifically why aren't there more examples in preservation?

With regard buckeyes - I had the pleasure of firing loco with a buckeye on the tender earlier this year, and I am not convinced that they "saved the crews a fair amount of time farting about with screw couplings". Don't forget that even with a buckeye, you still have to go between the vehicles to connect up vacuum and steam heat pipes once the buckeye is engaged, so there isn't a lot of saving in that regard - they aren't a truly automatic coupling.

Tom

 

IIRC they were the only uk examples fitted, the americans have all their locos & stock buckeye fitted. It makes sense tbh as it saves time coupling up, then just brake lines/power & eth or steam heat to connect.

 

With regards that I meant why weren't steam examples of push pull trains developed? I.E. apart from the autotrains & their tank engines they are the only example I can think of. Buckeyes I meant would save time as once their in the raised position, all that's needed is to pull a pin out to open the coupler, i've watched crews doing steam heat pipes & vac/air brake pipes never seemed to take them that long.

 

As said, push pull operation, under several different names, was common across Britain. So too were rail motors: a steam powered, self-propelled coach. These latter fell into disfavour due to their inflexibility: adding another coach in times of stress would be more than they could handle. Probably the best were the L&YR example, which seem to have had more power than most and could manage an extra vehicle.

The coupling issue was down to the unfitted goods trains common in this country. Throwing a three link coupling over with a pole was easy; no need to go between. Instanters were more of a problem: they could be uncoupled from outside, but if there was a way of shortening one with a pole, I never found it. For screw couplings or connecting / disconnecting brake hoses, a trip between was also needed.

It has to be realised how much of this hooking on and off happened; a given train might be remarshaled several times during its journey. This was easy with three link but would have been impracticable with a buckeye or screw couplings, or fully fitted. It needed block workings to make these viable. And if you have a centre draw hook on your goods trains, you logically have the same on your passenger stock up to the engine. Up to modern times, anyway.

 

Oddly, the LYR railmotors were the only ones numbered in the locomotive series, all others were in the coaching stock numbers, like DMUs were. Werent Instanters a GWR idea, reducing the amount of slack in a 3 link coupling?

 

I think in the USA buckeyes of a particular standard design were mandatory (correct me if I'm wrong).

In Britain there are, or were, at least 4 or 5 different designs of buckeye coupling all incompatible with each other. The side buffer arrangement were subject to RCH specification so guaranteed to be universal.

 

In the US, do you have to hook up the air pipes or is that part of the coupling?

Given the technology that existed at (say) 1920 could you have made an automatic wagon coupling that also coupled the brake pipe at the same time?

 

I recall an article in the TI or RM, the title being something like, "Wanted - an automatic coupling (but it must couple brake pipes)." So the answer is probably No.

As to the L&YR rail motors, the 'locomotive' was, pre-Grouping, numbered its own locomotive series and later in the LMS loco numbering series, but the coach part was numbered separately in its own coaching stock series, later in the general coaching numbers. When new, the two numbers matched, but there was one less coach than loco to allow for repair times so they were soon mixed up anyway.

 

I am pretty certain that on modern EMUs the brake pipes are connected with the coupling. Looking at the coupler on a class 323, it has what looks like a buckeye, with a connector mounted above it. I might be wrong though.

 

From my personal experience, coupling with a three link or even a screw coupling is far quicker than with a buckeye. With a buckeye you have to stop short, withdraw the buffers, set a coupling jaw open, align it, signal the loco/train together then do a pull test and, with luck, it will couple. If not, you have to repeat most of the foregoing again. And again until successful. Only then can you go between and couple the brakes, heat and any electrics. Coupling a screw coupling is a lot faster. Far from the norm but I have timed one NYMR fireman at 13 seconds from going between to getting back out.
As to why they didn't become universal, one major reason is the fact that the vehicle chassis has to be able to take buff and draw through a buckeye which needs a significantly different vehicle design to a conventional wagon. With several million wagons in use, the idea of a changeover for wagons would have been a nightmare as you would have required barrier wagons to couple the two different types of stock or provide all buckeye fitted wagons with drophead ones and retractable buffers at not insignificant extra cost.
The LNER & SR adopted Pullman gangways for their later coaching stock and these required buckeye couplers. This was perpetuated by BR for its corridor stock, but not for non-corridor stock, which continued to be screw coupled. One thing that has always baffled me, though, is why BR retained the British Standard Gangway (and screw couplings) for its first generation DMU stock.

 

I remember a similar title but have it in my mind that it was in an Ian Allan Locospotters annual for about 1961. Amongst others, the article featured the Dowty automatic coupler, which I think did incorporate the vacuum pipe in the couple head. I recall that 50 mineral wagons had been fitted as a trial. The fact that this coupling wasn't perpetuated tells its own story.

 

Can't argue, Steve, it's a long time since I saw it. But I think we read the same thing.

 

Others have answered about push-and-pull trains (auto trains, motor trains etc.) and also steam rail motors.

With regard coupling up - it's true that doing the vac and steam heat pipes doesn't take long, but the point is, it has to be done every bit as much with buckeyes as with a screw coupling - there is no time saving. As for the actual mechanics of coupling to fitted stock with a buckeye vs. a screw link, I think you underestimate the ease with which it can be done. To couple up, the driver has to go onto the stock while someone is on the ground pulling the coupling open; then the driver has to do a quick reversal to "pull away" to prove the coupling; followed by the person on the ground going between to do the vac bags. My feeling is that it is slightly more complicated and labour intensive relative to a screw coupling. There may well be other advantages, but a buckeye isn't a labour / time saving device like modern auto couplings. The real practical advantage only comes when all stock is thus fitted.

Tom

 

On the subject of automatic couplings, this is a demonstration (in March 1924, at Lancing), of the "Gearlock-Reynard automatic coupling", which appears to be somewhat similar in principal to a Buckeye, though what the precise differences were I don't know. With unfitted wagons, there would presumably have been no issue about automatically making brake connections, simply a coupling. Nothing much more was heard of the trial, which rather suggests the problems identified (issues about changeover; frame design of wagons to take the loads, etc.) were just as much of an issue.

(The wagon on the right, incidentally, is an Open A dating from 1899, so already 25 years old at the time of the trial - perhaps the manufacturer wanted to demonstrate a point about retrofitting to existing vehicles?)



Tom

 

I think having watched hump yard and flat yard switching operations in US and here in the UK, providing that you are using air brakes and that you only have buckeyes (no side buffers to get in the way) buckeyes are safer and quicker in both coupling and uncoupling. In the UK the combination of buckeyes and side buffers and the consequence of needing to be able to retract buffers etc meant that the only benefit was in a crash when a buckeye would hold the train upright and in line even if the bogies were ripped off. Our use of vacuum brakes meant that you couldnt (unlike in North America) reach in, twist two taps and then split the train.

 

I posted this in the WW2 locomotive topic earlier this month, but perhaps its worth a repeat. If not I apologise.

Buckeye couplings and Pullman gangways...
There was a joint trial across LMS and GWR which reported in early 1946. I've got a photo of the summary that was presented to the GW loco committee in December '46.

The GW fitted up 45 vehicles with buckeye couplings for the trial, and their joint conclusion with the LMS seems to have been that of the claimed advantages
1) reduced maintenance - no reduction could be confirmed
2) Safety to shunters - as shunters still had to go between buffers to connect vacuum and steam pipes they considered automatic coupling of marginal advantage
3 & 4) Telescoping and breaking loose - claimed that this was already being dealt with with improved drawgear and steel components.

the GWR didn't like the increased weight, and also felt that mismatched stock would be detrimental to timekeeping during the changeover period.

I'll summarise the conclusions as "not worth the trouble". Whether they were right or wrong I don't think I'm expert enough to judge.

 

It's worth remembering that the US did not transition from buffers and link couplings to Buckeyes, they replaced link and pin couplings, which were considerably more dangerous than either. I believe all Buckeye and tightlock couplings used in the UK actually use the same internal profile, which is also the same as that used in the US. However, there are several different heights of coupler and coupler body and once you put lower shelf brackets, air and electrical connections into the equation they won't necessarily couple.

You can probably do dangerous things with just about any system; Adrian Vaughan wrote an interesting account of an old porter teaching him how to couple a loose shunted wagon onto a stationary one using a shunting pole before it could rebound off - on Vaughan's first attempt the pole demonstrated leverage right back to him. The trick is always to make the safe thing to do the quickest and easiest option.

I do think the Southern Region system as used on EMUs, 73s and some 33s with drophead Buckeyes and high level air pipes has a lot to commend it, no need to go between at all and yet everything is compatible with a screw coupling if needed. That said, I do imagine the odd shunter must have cursed on seeing a train come in with the bags on the platform side neatly stowed...

 

Carriage working notices used to show notes to ensure the jumpers and brake pipes were connected on a particular side of the train to enable a formation to be split from the platform side, sometimes three or four trains in the future. It took a bit of working out at Waterloo with two separate "roundabout" services involved. On a slightly different angle drop head buckeyes were not the easiest of things to get back into the knuckle up position and slide the securing pin in....

The Southern nearly achieved a common coupling system for it's electric multiple units. Unfortunately on the South Western the final 4 SUBS were replaced with 508's, so we were no better off for the complexity of stock workings.

Cheers, Neil

PS Next time you're at Clapham Jn have a look into the Yard (Carriage sidings.) Note carefully that even with German thoroughness, Murphys law can apply. 450 and 444 units have the multiple jumper/brake pipe connection below the coupler. The new 707 units the jumper connection is above the coupler .....