jim.snowdon

On 08/06/2022 at 08:23, Covkid said:

True Jim, but it is only feasible if the formation doesnt change en route a la multiple unit.  You would have issues at terminals where you would need to run round or shunt, and i am not convinced the ORR would be too keen.

The primary requirement is that, as a passenger train, the brake is applied automatically in the event of a division (as per the 1889 Regulation of Railways Act). The critical element in this, for the Automatic Air Brake, is the Brake Pipe. The principal purpose of the Train Pipe is as a means of providing pressurised air to the brake control valve. The source and the control valve can be on different vehicles. The compressor could be on a support carriage within the train, and the locomotive at one or other end of the train. Running round is not a problem, as long as the locomotive has an independent means of braking - as is normally the case. Splitting the train en route is not a problem either, so long as the vehicle carrying the compressor remains with the locomotive.

Thinking about it, that is exactly what happened with the 4REP/33+TC sets that were used for the Waterloo - Weymouth services. Leaving Waterloo, the driver's brake control valve was at the front of the train, whilst the compressor was 8+ cars away on the 4REP at the back of the train. On arriving at Bournemouth, that would be uncoupled and replaced by the 33 (with its compressor) at the front of the train. Before anyone comments, I am aware that these units also had electro-pneumatic brakes, for which the Train Pipe also functions as an air main for the individual carriages, but that is a system that is overlaid on the standard Westinghouse type air brake which remains fully functional in its own right (and provides compliance with the 1889 Act).

17 hours ago, Wickham Green too said:

Does the air pressure actually have to be created on the locomotive ? ..... with a two pipe system Id've thought they could fit an engine driven compressor in the vastness of the support coach and just fit the application valve on the loco.

No, and what you propose is pretty much the way it works on a multiple unit.

25 minutes ago, kevinlms said:

I certainly recall reading in books written by LMS footplatemen, that they attended some sort 'engineman improvement league' (probably the wrong term), where they met IN THEIR OWN TIME to help junior loco crew understand how steam locomotives worked and how various pieces of equipment operation could be improved on. IIRC things like injectors and firing techniques were often discussed, with the aid of working models.

So perhaps there was no OFFICIAL discussion on something that perhaps undermined the railway company, but if they were discussing off duty, then they would likely to cover other topics. Importantly the would be no official written record.

 

But perhaps, I'm barking up the wrong tree?

What you appear to be referring to were better known as 'Mutual Improvement Classes', held outside of company time, but quite probably with the company's blessing as the results were in their interests.

Apart from the coupler, I believe the gangways are wider than the standard, probably due in part to the need to accommodate wheelchair passengers. Adjacent carriages are also coupled via inter-car dampers, required to achieve the necessary ride quality at the full 225kph, and I would expect the auxiliaries to be single-phase AC only, making them incompatible with non-electric locomotives.

Some sets are understood to have gone to Transport for Wales, where they will be run as sets topped and tailed by a DVT and an outer end carriage.

6 hours ago, corneliuslundie said:

I can report that rats definitely do chew electricity cables, but apparently according to our local rodent exterminator they can detect 240 volts and avoid those (and certainly the one which chewed our cables did). Not sure if they can identify the neutral though. Ours stuck to the low voltage cables, which at least were easier to repair. So what voltage are the feeds to point motors?

Jonathan

Fortunately, they seem to steer well clear of our 750V DC traction cables, although there can be all sorts of problems caused by mechanical damage where these cables have to pass under tracks in cable management sleepers.

6 hours ago, phil-b259 said:

However it should be noted that as all railway signalling circuits are deigned to be 'earth free' / floating with respect to earth, part of the regular maintenance tasks is to test all power supplies for how much is leaking through to earth - thus hopefully identifying damaged cables before you get to a stage where two bare cores can touch...

This is inclined to cause chaos when the earth-free 750V traction system gets into contact with the signal rail in single rail track circuit areas (and results in many very rude words being directed by S&T towards those in charge of the CRE. :( )

15 hours ago, Tom Burnham said:

I believe the only areas where 6.25kV was used in regular service were Glasgow and the GE lines out of Liverpool Street. I think the Shenfield 1500V DC electrification was initially converted to 6.25kV using the original insulators and then gradually upgraded.  It was certainly possible to tell whether you were in 6.25kV or 25kV territory by looking at the number of discs on the insulators.

Was there an experimental section of 6.25kV on the Styal line which was used as a testbed for AC electrification?

One of the papers presented at the 1960 BR Electrification Conference contains a table giving the route mileages of 25kV and 6.25kV electrification, both completed  and under construction. Crewe to Euston is shown as having 48 route miles of 6.25kV, although given the date, I would presume that this was a planned figure that may have reduced to zero by the time the relevant sections were actually energised. There is zero route mileage listed for the Manchester - Crewe and Liverpool - Crewe sections.

40 minutes ago, Steamport Southport said:

As part of the electrification project, were water columns removed where overhead was installed?

No, and the 1960 AC instructions include a whole appendix listing locations where the contact wire was raised sufficiently to permit safe access to the tops of tenders for the purpose of using water columns. Worth remembering is that the standard LNWR water column did not involve over the top delivery. Delivery was by means of a leather hose (ie 'bag')  that was fixed horizontally to the top of the column and dragged across the top of the tender until the free end could be dropped into the filler.

7 hours ago, Compound2632 said:

If you are looking for a load for your Hydra, perhaps a piece of agricultural machinery or traction engine would be more appropriate?

Or a covered horse or motor van - tall enough to warrant the use of a wagon with a well deck. There are certainly photographs of horse drawn delivery vans loaded on such wagons.

8 hours ago, 47137 said:

Might we expect the motor car to travel on the same wagon throughout its journey?

 

I am looking for excuses to include a better variety of wagons on my layout. Maybe some loads were transhipped part way on their journeys, and others were not.

Yes, and that applies to virtually everything. Transhipment between different companies wagons died out with the end of the broad gauge as far as the main line railway network was concerned. Transhipment, or more properly consolidation, did occur at certain locations as a means of making more economic use of wagons by combining the loads from lightly loaded wagons into a smaller number of fully loaded ones.

7 hours ago, 47137 said:

I was rather thinking of the GWR Hydra wagon to diagram G19 when I made my post, because Connoisseur Models do a kit. And I want to try building one of these for my layout set in the middle of Essex, a fictional railway connected to GER metals.

An unlikely wagon to be used for motor car wagon, being a more specialist wagon for higher vehicles. The most likely candidate for shipping a motor car would have been one of the covered or open carriage trucks - the GWR's Pythons and Scorpions.

17 minutes ago, The Johnster said:

ISTR being told by my brother-in-law, who was involved with the design and build of the Class 81 locomotives as an employee of A.£.I., that the wires on the sections south of Crewe carried 6.25kv in certain station and yard areas, and to avoid rebuilding overbridges, to reduce the flashover risk.  He was responsible for the switchgear (his speciality) that allowed these locos to change between the 25kv and 6.6kv sections.  The 6.25kv sections had the wires set lower, which was the reason that some steam locos were banned south of Crewe.  North of Crewe, it had been decided that all the OLE would be at 25kv and the clearances were set accordingly, with the wires at the full height above the rail throughout.

 

If this is nonsense, blame my bil not me!  Of course, it it is correct, I claim full credit...

 

 

You're mostly right, but the whole reason for the reduced voltage was to cope with what were then considered safe electrical clearances to both structures and rolling stock. The lower wire height was countered by the smaller electrical clearance required.

The clue will probably lie in the later editions of the AC Electrified Lines instructions that covered the full extent of the London and Birmingham electrification, but I haven't got a copy.

3 hours ago, LMS2968 said:

South of Crewe. Steam continued to operate under the wires around the Liverpool and Manchester areas and from the North into Crewe - but no further with a yellow stripe.

The 1960 AC Electrified Lines Working Instructions make no mention of yellow stripes or restrictions on steam locomotive operation, but at that time only the wire between Crewe and Manchester were live. Liverpool was included in the diagrams, but sothwards, the electrification stopped as Basford Hall. Ergo, whatever the restriction was, it existed only south of Crewe.

45 minutes ago, bodmin16 said:

I don't know about the areas that were subject to the ban, but I would suggest that it related to specification of the OLE in some areas, the loading gauge of some locomotives or a combination of both.  I am basing my assumption on the fact that there are currently preserved locos with no cabside stripes running under the wires on the mainline network, this would further suggest to me that the clearances are greater now bearing in mind things are probably more risk averse than back in the 60s.

The clearances are just as tight, nothing significant having changed about the railway since electrification, but the values of the minimum electrical clearances have reduced over the years as understanding has improved. Similarly, the use of 6.25kV as a means for getting electrification through tight spots has disappeared entirely.

On 04/05/2022 at 23:46, Hal Nail said:

This meant that all paint manufacturers had to guarantee that anyone else's BR colour could be used for touching up, so they were all identical after 1954."

Except that paint to a standard straight out of the can will not match the colour of the paint on a loco that has been out in all weathers for any number of years. That's why car body repair shops now match the paint to the car, not the original manufacturers reference.

On 05/05/2022 at 13:52, Clive Mortimore said:

I don't worry too much as my colour memory is not brilliant but this I do remember if two locos were the stood next to each other and were the same shade of green it was by accident.

The same is true of the prototype, a fact that is conveniently forgotten by modellers.

5 minutes ago, Compound2632 said:

 

@jim.snowdon sorry, I think I failed to read this when first posted. My question is, as always, to what period do these statements apply? In other words, what is the date of the RCH regulations to which you refer?

I was quoting from the December 1937 regulations. The same text appears in the 1953 BTC/BR regulations, apart from the reference to the back pressure check on re-tyred wheels with cast iron bosses. By 1953 wheels with cast iron bosses and in need of re-tyring were to be scrapped instead.

49 minutes ago, Compound2632 said:

 

But would there normally have been any cause to take wheels off axles? Would journal wear by the issue?

Yes, or irrecoverable journal damage as a result of bearing failure (or theft). And, as I was reminded by rereading the wagon repair regulations, when overheating of the journals had led to brass penetration of the steel journal.

On 07/05/2022 at 14:30, Cwmtwrch said:

The 03 'match truck' was normally there to ensure that track circuits were activated, the loco on its own being insufficiently reliable in this respect. It would therefore need the match truck on the main line as well, unless attached to something else which would serve the same function.

Only in fully track circuited territory, and even then the problems that required the use of a semi-permanently coupled runner were really only in complex S&C areas where insulated joints had to be staggered out of necessity.

21 hours ago, BR60103 said:

Could someone explain what would wear out on the centre of a wheel that it would need replacing?

 

The hole. No, this is not normally a part of the wheel that wears, but if the bearing journal becomes too damaged as the result of a bearing failure (a 'hot box') it may become economic to recover the wheel centres and fit them to a new axle. The axle is a force fit in the hole in the wheel centre and removal and refitting will slowly degrade the quality of the fit between the two, so there is a practical limit on how many times this may be done.

This is where there is a significant difference between wheels with cast steel or wrought iron bosses and those with cast iron bosses (invariably split spoke wheels). The latter were not permitted by the RCH Regulations on wagon repairs to be re-axled.

The same regulations also give a clue as to the longevity of split spoke wheels with cast iron bosses, in that there is a requirement that whenever they are re-tyred, the wheels must be subjected to a 'back pressure' test of 50 tons, which I interpret as being an attempt to pull them off the axle. If an applied force of 50 tons did not dislodge them, the wheelset passed and was stamped accordingly. Otherwise, they failed and were deemed unfit for further use.

The same principle apply to modern monobloc wheels, which have to be replaced when the rim reaches a minimum thickness. There is a limit to how many times the axle can be fitted with replacement wheels.

2 hours ago, Wickham Green too said:

Split spoke wheels go back to day one of railways / plateways and were a fairly straightforward forging job. Solid spoke wheels had to be cast so required a foundry and a completely different set of skills - as you say Gods Wonderful Railway favoured this form of construction and presumably having loco and carriage works on the same site at Swindon may have influenced this. Disc wheels require metal spinning - again a totally different technology .... presumably the cost of this reduced in the thirties so new wheels were often made this way - though a LOT of old wheels were re-used under new wagons well into BR days. Initially all three types had separate tyres - but monobloc disc wheels became standard latterly ....... I guess this was post war following the import of American wagons thus fitted - it was a far older technology but I think we Brits were waiting for our metallurgical skill to catch up - and for there to be a ( cost ? ) incentive to change.  

My understanding is that for a long time, split spoke wheels were cheaper than solid spoke wheels, possibly helped by split spoke wheels being forged wrought iron, whereas solid spoke wheels were cast steel. This shows markedly with PO wagons, where solid spoke wheels are virtually non-existent and split spoke wheels were all but ubiquitous, except for a period in the 1930s when some wagons appeared with three-hole wheels. The latter are forged from steel billets using specialised ring rolling techniques, but there were companies in the UK who specialised in this. Steel, Peech & Tozer were one, and the process for manufacturing these are fully described in the film 'Steel Ride', viewable on youtube at -

The preference for some railways to use solid spoke wheels may have been down to a preparedness to invest in better quality and/or longer life that the PO wagon industry. Wheel centres and axles can last a very long time, and with periodic tire replacement can be recycled from old wagons to new as they are replaced.

The US built wagons imported during WW2 may have been an influence in the adoption of monobloc wheels, but then so would the search for a lighter wheel. The wheelset, plus the axleboxes, all constitute unsprung weight and engineers were aware that this was a factor in track deterioration. The US wheels would have been cast iron, with chill hardened rims - cheap and cheerful by European standards, and a standard that persisted for decades (if it isn't still current). The iron is not, obviously, bog standard cast iron as that would be too brittle, but I would expect it to be one of the grades of ductile iron.

4 hours ago, The Stationmaster said:

Oh yes there is!   If you use channel rodding there is no low profile rodding roller so standard rollers have to be used.  Reading produced a low profile roller for use with round rodding which was designed, and obviously used for, cross rods hence round rod was used.   If a normal height roller assembly was used it meant that the roller stools had to be set considerably  lower than their normal height of the top of the stools being level with the top of sleepers (thus ensuring that the rollers would be well clear of any ballast etc).

Interesting. It leaves you wondering what other regions did.

On 29/04/2022 at 11:27, The Stationmaster said:

Don't forget that GW(R) cross rods (going under track) always used round rodding.  That continued even after channel rodding was introduced for the main rodding runs. 

Dare one say 'how typical of the GW'? There isn't an obvious reason for such a convention.

Paul Bartlett's ever useful website contains several collections of what are described as LPG tank wagons -  https://paulbartlett.zenfolio.com/fueltankwagons

It's almost certainly been rebodied at some time, probably by the Dockyard given its location. The ironwork will be original but wasn't designed for four planks, the giveaway being the extent to which the bolts don't fit the planking.

It probably is of Midland origin, but axleboxes can be deceptive, being interchangeable to quite a high degree.

It is something that I was looking at late last year, as the conductor rail diagrams for the Southern Region are clogged up with grid references for all sorts of lineside features (and missing many other useful features). Some inquiries of contacts who work in the emergency services confirmed that OS grid references are not normally used (although they would not be ignored). An app by the name of Goodsam is in common use, not least because the caller's phone can be interrogated to give its location and it will allow for a video link to be established, which can be helpful in assessing the patient/victim. 'What 3 Words' is also useful.

As far as routine maintenance and the logging of defects is concerned, the railway is, as far as I can see, still very much immersed in the linear work of ELR and miles and chains, even when it is only signed to the nearest 20 chains (ie a quarter mile), if you can find the milepost amongst the vegetation and not infrequently in the dark.

14 hours ago, DY444 said:

 

Indeed and that will never change until the ORR is forced to treat the cost benefit of its pronouncements as a fundamental component of its decision making.  There are plenty of problems with the GBR proposals but one of the biggest imo is the failure to recognise the insidious impact of the ORR on the the cost of infrastructure projects.  There is a very long list of things wrong with the railways but the ORR's aloof attitude to ALARP is right up there and yet nobody in Government can see it or is too scared to address it.

The problem lies, not with the ORR, but with the unwillingness of both the Train Operators and NR to challenge the 'safety at all costs attitude' that actually originates from the RAIB.

The underlying problem is that the RAIB, at its creation, was given a remit of making safety recommendations without any accountability for the cost. At first sight, this ought to be a good thing because their conclusions should not be coloured by financial considerations. The ORR (HMRI) is the safety authority, and as such is the first filter for whether 'as safe as is reasonably practicable' has been observed. Ultimately, if a decision is required, it has to go before the judiciary. In the days of BR, there were sufficient senior people with real practical experience to make proper assessments of the practicability of safety measures, and the Inspectorate could, and did, operate a very gentlemanly arrangement of quiet pokes and prods, with the Law kept in the background for use only if necessary.

We are now in a much more commercially cutthroat age, where train operators, many of whom have links to the bus industry, are notoriously risk-averse. They will positively resist raising any challenge against authority. For some of us with more familiarity with the UK tramway sector, one only has to look at the way in which UK tramway safety is now diverging from European practice, expensively.

55 minutes ago, Cwmtwrch said:

Working 5-600 ton unfitted coal trains downhill with an 0-6-2T and one 20T brake meant that very low speeds for the whole trip were essential to maintain control of the train, even with quite a few wagon brakes pinned down.

Essentially, loaded trains were almost hauled downhill.