9F Locomotives - Restrictions on Network Rail

I appreciate that that was done but it was after the available 4-4-0s got a bit long in the tooth. They certainly ran round the curves better; I've been to Mallaig behind a Black 5 to the accompaniment of the noise of rails and flanges being ground away.

 

A Black 5 is really not the right loco, 'a wee bit high in the wheel' as one of the drivers told me. The FW 5s were never used on the Mallaig road, the turntable there was to small.

 

I didn't know that but I was talking post-turntable when they had to run backwards anyway.

 

75014 was well regarded but limited to six? Whether a double chimney version would be allowed 7 is open to conjecture. Was told a long time ago that 75078 was felt to be a coach stronger than 75014 when compared on KWVR.

 

Getting back to the subject in hand, I note that while all the coupled wheels on a 9F have the normal 1 in 20 taper for the tyre tread, the flangeless driving wheel set have a parallel tread. As it is desirable that all the wheels are of the same diameter this raises the question as where between the outside of the tyre and the beginning of the radius leading to the flange is the nominal diameter measured on the coupled wheels?

 

Someone did post the measurement point for the nominal diameter on one thread or another. Can't find it though.

 

Not so. There is a misapprehension that "open access" somehow puts the owner of railway infrastructure to accept anything that gets proposed. "Open access" was never intended to let prospective operators do what they liked, indeed an application to the ORR to become a "open access" operator requires the operator use stock that complies with the relevant group standards specified by the infrastructure owner, plus there must be paths available in the timetable to accommodate such operations. Also under the ROGS legislation, infrastructure owners are required to ensure the standards they impose adequately mitigate the risks their infrastructure presents - not what may have been OK 60 years ago.

So "open access" makes no difference to the issue - namely that the infrastructure owner specifies in its group standard that flangeless wheels (just like trains not fitted with a contentious automatic brake between the first and last vehicle) are prohibited from its network and the fitment of AWS / TPWS, secondary door locks, etc are mandatory. You cannot use "open access" or any other privatisation / EU legislation to change this either, as its entirely possible to show that the prohibition is there for sound technical reasons plus any attempts to make a special dispensation for a single type of motive power would represent an excessive drain on resources.

I don't doubt that some are interested in finding a solution - a 9F back on the mainline would be an impressive sight after all. However supporters need to stop thinking they can somehow bend the rules to suit themselves or 'somehow force NR to accept something that has been prohibited for sound technical reasons. The bottom line is that for a 9F to return to the mainline it needs to be fitted with flanges on all driving wheels and be able to cope with raised checkrails*. The question is can this be achieved without totally destroying the 9F in the process.....

*As an aside - have a look at the extra high check rails being installed for the Tram-Train trial at Rotherham. This is because the wheel flanges on the tram-trains need to be much thinner than those of normal trains, so they can fit in the grooves on street track. It's not only models where the back-to-back is important; the result with a normal check rail would be that the opposite flange could go the wrong way at the crossing (frog) before the back (inner face) of the thinner flange came into contact with the check rail to prevent it. Hence the tram-train wheel thickens at the back just above the top of the running rail to be the same back-to-back as heavy rail wheels, and this thicker part engages with the raised check rail. You'll see the same on the off-street points of Manchester Metrolink. Note that these special tram compliant check rails do not make any difference to how the check rail works with respect to railway vehicles so the group standards are unaffected by their installation - the only difference they represent is that some vehicles like snowplough fitted diesels and independently propelled snowploughs are now barred from routes fitted with said pointwork.

 

I have no direct information so it would need someone from the Class 40 Preservation Society to confirm but I would expect that the running of D345 on the main line would include a route analysis to confirm suitability and identify speed restrictions as necessary. In Southport, for example, the main problem is the curvature at Meols Cop station where the sharp reverse curve entering the station on an eastbound service would require caution that would be identified when checking the proposed routeing yet D345 has visited during November 2014 with a charter to York.

 

I thought the specific issue with the 1-Co-Co-1 classes (especially the Peaks) in Glasgow had to do with the tight point geometry near Central, not the flanges.

 

Route availability is not the same as group standards.

The Class 40 may well have routing restrictions based on certain characteristics - but that is no different to the class 67s having routing restrictions. A class 40 is however it is fully compliant with group standards as regards wheel flanges - a 9F is not.

 

There is certainly no proposal to bend any rules and any questioning of the situation is merely that, a genuine seeking of knowledge. If flangeless wheels are prohibited the only question arising is whether there is a mechanism to seek a review by providing sound engineering evidence to invite consideration of alternative thinking. While there may be a notional process, the possibility of it being invoked is extremely remote it is safe to say.

 

I'm afraid that I'm ignorant of Class 40 bogie design, but I would imagine that, if necessary, both the central powered axle and the non-powered preceding axle could have sideways play, something not easily possible with a rigidly-coupled steam engine.

 

Group standards are of course open to review - whiteness the (misguided in my opinion) change where allegedly expert analysis has allowed the removal of the requirement fro a yellow panel if the headlights are arranged in precisely defined positions and are of a certain standard.

The process of how such a review starts is less clear however - in the case of the yellow ends it was driven by the need for the UK to align its rules to those laid out in the EU -interoperability regulations designed to harmonise all railways across the EU - a body the country voted to leave a few months ago....

In the case of moves to change the situation with regard to flangeless wheels I'm not sure who would be the lead party. In rolling stock matters this would normally be a ROSCO or a builder starting the ball rolling - helped by franchises that might have an interest in the group standards being amended. However such change would need lengthy analysis and is not a quick or cheap process.

 

Really? There is absolutely no reason why British trains should not have yellow ends. It's just that we couldn't prevent others without yellow ends from use here. The event you refer to a few months ago was a giant public opinion survey. Brexit might never happen and if it did there is unlikely to be any influence on the interoperability agreements.

 

Evidently not quite as simple as said, but would that be achievable? The 04 diesel shunters had a similar set up, but that being from rotary driven source rather than a crankshaft. Were any steam locos designed as such? Would it allow reduced hammer blow?

 

The initial issue of Class 9's operating on the main line was, as we all know, due to concerns about raised check rails through S&C. However, there is now a much more serious issue which more or less removes any chance of a vehicle with flangeless wheels operating on the national network. For about 15 years now the chosen method of train detection has been changed from Track Circuits to Axle Counters. (AC's) The actual method of operating is the same as track circuit block, but there are no track circuits. Each section has an axle counter at the beginning and the end. In very simplistic terms, the entry counter 'counts' the number of axles entering a section, the exit counter counts the axles leaving the section. When X equals Y, then the section indicates 'Clear'. AC's are more reliable than Track Circuits, so performance is improved. The Safety case for AC resignalling schemes specifically precludes the use of vehicles with flangeless wheels as there is no way to tell if a flangeless wheel will operate AC's reliably. This could lead, at worst to a wrong side signalling failure, with a track indicating clear when occupied. Even if it fails 'Right side', it would lead to sections showing occupied when clear, and hold signals at danger, requiring Drivers to be 'Talked by'. This would have a major impact on performance.
Most of the WCML, GWML, West Mids, Nottingham/Erewash, Heyford /Banbury/Leamington/Snow Hill & Stratford OA, are all equipped with AC's, and there are pockets of them in otherwise TC areas. Sea Wall at Dawlish is one, where sea water caused TC failures, so AC's were installed very early.
AC technology has come on massively in the last few years, and reliability is very high. Sadly though, not compatible with Flangeless wheels.

 

The painting of vehicle ends yellow long predates the EU (with us as part of it). It was a safety 'improvement' in BR days, about 1966 to improve the visibility of trains to persons on or near the line. Many foreign Railways don't paint train ends yellow. I also believe that the requirement for Yellow ends has recently been removed in the light of the tightening up of rules and regulations for people being on or near the line when open to traffic. Sadly, many European Technical standards for Interoperability (TSI's) have now been enshrined in British legislation (ROGS etc.), so even if/when we leave the EU, they requirements will still be legally required in GB.

 

There were a few in the early to mid nineteenth century - this is an SER example:



Source: http://vads.ac.uk:8080/large.php?uid=216947&sos=0

From memory, the LC&DR had what was in effect an 0-6-0 with the middle driving wheels removed; they were later rebuilt as conventional 0-6-0s. I think the objective at the time was to prevent crank axle failures on the uneven track of the era.

I think on the issue of hammer blow (maybe someone else can think harder than my tired brain), if you hypothetically removed the tyre on the middle driver so it wasn't in contact with the track, but left everything else (i.e. wheel centre and balance weights etc), then across the whole loco, you would still have the same cyclic variation in load. However, none of it could be supported by the centre axle, so it would have to be re-distributed to the other four axles. So I think it would make the situation worse, not better.

Tom

 

This is one of several "wheezes" by a sort of 19th Century precursor of O.V.S. Bulleid called T.R. Crampton. Although one of his types was successful in France his machines were troublesome in the U.K., one of the problems being track damage!

Not really relevant to the present thread is that he was about the first to realise (I seem to recall) the advantages of longer valve travel. However the other problems of his creations led to this advantage being overlooked.

Paul H

 

I agree with your hypothesis. You might choose to apply the reciprocating balance entirely to the jackshaft (as the centre axle has now become), which would probably ease the hammer blow peak forces, since they'd be applied to sprung mass rather than unsprung. This would allow some of the vertical out-of-balance force to be absorbed in vertical acceleration of the sprung mass if the spring rates are low, but possibly at the expense of the locomotive pogo-ing down the track. If the springs are assumed to be infinitely stiff then it makes no difference except distributing the same total force over fewer axles, as you originally suggested.

The more I think about locomotive balancing, the more I think the 2-cylinder engine is quite a crude configuration and that Gresley had a good point with his advocacy of three cylinders.