Manchester Piccadilly OHLE question.

[Dava]

1 hour ago, jim.snowdon said:

Purely hypothetically, but based on the experience of having been a traction equipment engineer earlier in my career, I would think that conversion of an EM1 to 25kV AC operation would have been doable. All of the DC equipment would have been stripped out, which would have left a fairly empty bodyshell. The major components of an AC equipment are, essentially, the transformer/tapchanger unit, the rectifier(s) and the reversers (which the EM1 would have had anyway). It would all have had to be above floor level anyway, as the bogies occupy all the space underneath.

 

What you could not have done at the time would have been to convert one of the ALx AC locos to dual voltage capability, basically as the more compact equipments available with solid state control had yet to be invented. I don't think there is anywhere near sufficient room inside any of the ALx locos for a complete DC traction equipment.

 

What is possible, but by no means certain, is that the loco in question could have been despatched to GEC's works at Witton for use as a load bank - the EM1s (like most DC locomotives) would have carried a quite highly rated resistor bank. It was, after all, for this reason that four of the ex-Metropolitan electric locomotives ended up at Rugby, even if they never got used for that purpose. We shouldn't forget that the LMS test train incorporate three cars whose purpose was to act as rheostatic brakes, dissipating the test locomotive's power into on board resistors.

 

Conversion of the EM1s to AC might have been technically feasible but unlikely for financial and other reasons. They were based on a Gresley era design of 1938 and built like tanks. The articulated bogies and their impact on the rails limited speed and their utility away from Woodhead would have been limited.

 

It’s the type of project that in a BREL 1970s works would probably have gone over budget because of unanticipated problems and resulted In a loco of Iimited use.

 

I was sorry to see them go, but in Thatcher era Britain with coal, steel and power being run down, there was no future for Woodhead.

 

Dava

[Edwin_m]

On the major assumption that space could have been found for a transformer and rectifier, a dual-voltage or even an AC-only locomotive could have been produced by feeding the rectified DC into the existing DC control equipment.  BR did this with the GE units that were built for DC but continued in service after the lines were converted to 25kV, and I believe SNCF's dual voltage locomotives before the advent of traction electronics were done in the same way.  They'd have had to disable the regenerative braking though.

9 hours ago, GoingUnderground said:

3rd August: EM1 No.26014 was towed from Reddish depot to Soho electric depot, Birmingham for conversion to AC/DC by G.E.C. Witton. It went to General Electric Co.'s Soho works. The converted EM1 was to have trials hauling freight on the WCML in place of the AL6 a.c. locomotives which were giving trouble at that time. The conversion/trial was obviously not a success and we hear no more of the aforementioned."

 

I too was surprised as I would have thought that there was already a wealth of experience on the abilities of EM1 to haul freight. As pointed out above, a considerable amount of advance design work would have been needed before any physical conversion could have taken place. I am not a mechanical or electrical engineer, but I would have thought that in addition to the lack of space, the additional weight would have caused problems with axle loadings.

 

I agree it would have been pointless assessing the haulage ability of the EM1 on AC lines.  I suggest if a conversion was being contemplated it was more likely it was taken to Soho, as a place reasonably convenient to Witton, for GEC to crawl all over it and see if there was any possibility of adding said transformer and rectifier...

1 hour ago, jim.snowdon said:

Purely hypothetically, but based on the experience of having been a traction equipment engineer earlier in my career, I would think that conversion of an EM1 to 25kV AC operation would have been doable. All of the DC equipment would have been stripped out, which would have left a fairly empty bodyshell. The major components of an AC equipment are, essentially, the transformer/tapchanger unit, the rectifier(s) and the reversers (which the EM1 would have had anyway). It would all have had to be above floor level anyway, as the bogies occupy all the space underneath.

... or indeed of doing something more radical along these lines.  I suspect it would have taken them about five minutes to come to the conclusion that was somebody's crackpot idea and totally impractical.  

Edited July 6, 2021 by Edwin_m

[jim.snowdon]

5 minutes ago, Edwin_m said:

On the major assumption that space could have been found for a transformer and rectifier, a dual-voltage or even an AC-only locomotive could have been produced by feeding the rectified DC into the existing DC control equipment.  BR did this with the GE units that were built for DC but continued in service after the lines were converted to 25kV, and I believe SNCF's dual voltage locomotives before the advent of traction electronics were done in the same way. 

Space is the critical element, and when BR converted the 1500V DC Shenfield and LT&S units, they had the benefit of being able to put the 25kV equipment under an adjacent coach, leaving the DC traction equipment where it was.

 

Dual voltage locomotives were technically similar, in that the transformer/rectifier set simply feeds constant voltage DC to a traction equipment. The only part that has changed is that the DC equipment has successively moved from being resistive, to DC Chopper with DC traction motors to 3-phase inverter with AC traction motors.

 

[roythebus1]

On 03/07/2021 at 11:38, Grovenor said:

If the contact wire was omitted on the linking crossovers, then any electric train accidentally taking the route would have the pan rise up into the overhead likely causing extensive damage to both pan and OHLE, not something you want in a busy station throat. In fact my recollection was that in line contact wire insulators were fitted, I am surprised to see the catenary style insulators in the pics as these also represent a hazard should a pan run into them. Without the damage scenario the electrical protection would be activated pulling out the breakers, blowing fuses etc and the train could be rescued without needing days of rewiring.

I'm certain you're right there Keith. I worked int Manchester Piccadilly when I was 2ndman at Rugby in 1974. Only a few times mind, but ISTR seeing the contact wire insulators between the 2 systems. 

 

there was also some discussion about this matter at the MRC in the late 1960s when someone (Bill Gardiner I think or maybe Roger Stone) said that if a DC loco went on the AC, the lightning detector on the loco would think "oh, I've been hit by lightning" and a circuit breaker would open.

 

It makes sense to have the double isolating sections in the contact wire as the danger of 25kv and 1500 mixing would be very real, even from induced current.  The last thing anyone would want was an extensive dewirement in the area. At least a dead loco could be easily rescued in those heady days.

 

[Grovenor]

Hi Roy, glad I'm not the only one remembers this !!

[roythebus1]

 Collective memory fade is a wonderful thing. We used to go to Manchester every Christmas for the exhibition and being youthful and interested in trains at the time I used to notice odd details like this.

 

To answer others, I don't see why the AL6s were out of service in 1967, after all they'd only been in service a year or so. I'm aware of the problems with axle hung traction motors, have you ever tried pouring from a tea can into a cup at 100 mph on one?

 

The old system at Aachen has now I believe reached the end of its life and is DB ac on one side and NMBS/NS electric the other side. Through trains drop the pan and coast into the platform where the loco is uncoupled and taken away by diesel shunter. The departing loco is backed on with pan up and after the brake test and other station duties, leaves on the other voltage.

 

I was told of a through freight that had the Belgian loco back on and the DB diesel would shove the train up the steep bank. The DB driver thought the Belgian wasn't working that had and at the top of the bank he dropped back and the train carried on. The problem being there was no Belgian loco on the front! The train is reportedly being stopped after a couple of seesaw movements and the air in the brake pipe being lost. But I digress...

[298]

15 hours ago, DY444 said:

 

Don't disagree with any of that but it seems to me replacing the rectifiers and fitting air brakes to the 83s and 84s (as was eventually done) would have been far cheaper and easier if the aim was simply more AC locomotives.  The 84s did have mechanical problems later in their lives, and this was ultimately their undoing, but at the time of storage the only major headache on both classes was the rectifiers.

 

 

 

Something we've always needed in the UK is a basic CoCo AC electric, the four axle types were fine most of the time if driven properly but they were never very good at grinding up a hill with a heavy load. The EM2s may have made better conversion subjects for this but the basic fact is it never happened.

 

On a similar note (apologies if it's been mentioned previously) are the four Met electrics that reached Rugby in the 60s for evaluation into into possible conversions, again nothing happened but it's difficult to see how they could have been used for anything other than simple third rail use.

[DY444]

38 minutes ago, 298 said:

 

Something we've always needed in the UK is a basic CoCo AC electric, the four axle types were fine most of the time if driven properly but they were never very good at grinding up a hill with a heavy load. The EM2s may have made better conversion subjects for this but the basic fact is it never happened.

 

Indeed however the electrified part of the WCML in the 1960s wasn't really a "grinding up hills with a heavy load" kind of railway.  Plenty of gradients certainly but nothing like Woodhead or the northern fells.

Edited July 7, 2021 by DY444

[adb968008]

21 hours ago, woodenhead said:

An interesting thought about Woodghead - it would have been 304s to Hadfield,

304’s did goto Woodhead.

indeed conversion / withdrawal of 506’s brought the need for 303’s from Glasgow.

 

A class 307 also worked the line for 1 weekend, a Regional Railways North West event, but went largely unnoticed due to distractions like 20/26/56/60 on Manchester-Barrow workings.

 

also side note, but on flickr is E26014 at Reddish on August 1st 1967 

(not my image/url)

[GoingUnderground]

8 hours ago, 298 said:

 

Something we've always needed in the UK is a basic CoCo AC electric, the four axle types were fine most of the time if driven properly but they were never very good at grinding up a hill with a heavy load. The EM2s may have made better conversion subjects for this but the basic fact is it never happened.

 

On a similar note (apologies if it's been mentioned previously) are the four Met electrics that reached Rugby in the 60s for evaluation into into possible conversions, again nothing happened but it's difficult to see how they could have been used for anything other than simple third rail use.

I've not knowingly come across references to them being considered for AC conversion, or conversion into anything else come to that. But they did seem to have some sort of role in the work that BR was undertaking on AC traction at the time.

 

To quote from the updated/second edition of Ken Benest's "Metropolitan Electric Locos":

"Nos 2. (Oliver Cromwell), 7. (Edmund Burke), 16. (Oliver Goldsmith) and 18. (Michael Faraday) left Neasden for Mitre Bridge Electric Car Sheds on the London Midland Region of British Railways at Willesden. It is understood that they were taken over for experimental work by the Electrical Engineer's section for work connected with a.c. traction and were moved to Rugby motive power depot on 1st March 1965. It is believed that they were cut up there in July 1966."

 

It also says that the motors and roller bearing armatures on the 8 Metrovics scrapped by LT shortly after they were withdrawn in January 1962 were sent to the Southern Region. The same thing may have happened to the Rugby 4, always assuming there was some joined up thinking going on in BR at the time.

 

So we have another 4 DC locos, the Rugby 4, mentioned as being involved in an unspecified way in BR a.c. traction experiments.

Edited July 7, 2021 by GoingUnderground

[jim.snowdon]

9 hours ago, 298 said:

 

Something we've always needed in the UK is a basic CoCo AC electric, the four axle types were fine most of the time if driven properly but they were never very good at grinding up a hill with a heavy load. The EM2s may have made better conversion subjects for this but the basic fact is it never happened.

 

On a similar note (apologies if it's been mentioned previously) are the four Met electrics that reached Rugby in the 60s for evaluation into into possible conversions, again nothing happened but it's difficult to see how they could have been used for anything other than simple third rail use.

Which is largely why out of the four contenders for the Channel Tunnel shuttle locomotives, the two 4-axle types lost out to a 6-axle electric. (The fourth contender was also 6-axle, but had other features about it that didn't make it a serious contender.) From that successful Brush/ABB loco came the BR Class 92 which, as far as I am aware, has always given a good account of itself in freight haulage. The sad part is that with UK electrification being so patchy, the diesel powered Class 66s rule the roost by being able to go anywhere without anyone worrying about loco changes.

 

As regards the 4 Rugby ex-Met locos, I thought that what was in mind for them was simply use as mobile load banks for testing the 25kV distribution equipment. Never any conversion to AC operation.

 

[dave75]

You can't blame BR for having a look, at the time, the AL3 and AL4s in store and in need of expensive refits. 

 

EM1, with an availability of 90%, if you can fit the gear to rectify 25k - dc you've got a useful reliable motive power. 

Single AC Pantograph and Air tanks in the space for the second, be an interesting project. Any thoughts on a number series E36014?? And a TOPS class 86???

 

 

[MidlandRed]

On 07/07/2021 at 09:42, adb968008 said:

304’s did goto Woodhead.

indeed conversion / withdrawal of 506’s brought the need for 303’s from Glasgow.

 

A class 307 also worked the line for 1 weekend, a Regional Railways North West event, but went largely unnoticed due to distractions like 20/26/56/60 on Manchester-Barrow workings.

 

also side note, but on flickr is E26014 at Reddish on August 1st 1967 

(not my image/url)

Thanks for posting. Looks almost, if not, ex works (esp red buffer beam)? I recall it was blue at Soho and very clean - was parked next to the perimeter fence to the canal toe path, outside the building - and thus visible to youthful spotters (quite an exciting sight!!) 

Edited July 15, 2021 by MidlandRed

[SamThomas]

On 30/06/2021 at 20:59, Michael Hodgson said:

large height detector triggered sign that suddenly starts flashing yellow lights and an illuminated legend reading "Overheight Vehicle Divert".

 

Unfortunatly, a number of these signs are calibrated incorrectly & operate when high vehcles well within the height allowed approach.

[Michael Hodgson]

8 hours ago, SamThomas said:

Unfortunatly, a number of these signs are calibrated incorrectly & operate when high vehcles well within the height allowed approach.

It should put them on alert that they may be too high, and if they believe that not to be the case they ought at least to approach slowly enough to check.  The signs sometimes seem to get stuck in the active condition when there's nothing about - I suspect that they may be detecting overhanging tree branches that ought to be trimmed.  Or maybe there's some sort of "fail safe" logic coming into play.

[SamThomas]

4 hours ago, Michael Hodgson said:

It should put them on alert that they may be too high, and if they believe that not to be the case they ought at least to approach slowly enough to check.  The signs sometimes seem to get stuck in the active condition when there's nothing about - I suspect that they may be detecting overhanging tree branches that ought to be trimmed.  Or maybe there's some sort of "fail safe" logic coming into play.

As an example trhe one pictured is signposted at 13'6" - up untill a year or so ago I regulary drove HGV's that were 12'8" (actually measured & they had self leveling air suspension) so I knew they were well underheight.

However, the warning signs were tripped by every single vehicle in the fleet.

The Local Council, TfL, Network Rail & Highways Agency were all contacted & informed about the issue & none of them accepted responsibility for the problem or appeared to get it sorted.

 

I'm not condoning the actions of HGV drivers who strike bridges but the authorities need to get their house in order too.

[DY444]

6 hours ago, SamThomas said:

As an example trhe one pictured is signposted at 13'6" - up untill a year or so ago I regulary drove HGV's that were 12'8" (actually measured & they had self leveling air suspension) so I knew they were well underheight.

However, the warning signs were tripped by every single vehicle in the fleet.

The Local Council, TfL, Network Rail & Highways Agency were all contacted & informed about the issue & none of them accepted responsibility for the problem or appeared to get it sorted.

 

I'm not condoning the actions of HGV drivers who strike bridges but the authorities need to get their house in order too.

 

Yes but the flip side to that is that particular bridge at Tulse Hill has been in the top 10 of struck bridges nationwide for as long as I can remember.  During my time commuting into London Bridge it was struck at least once a month and continues to be struck regularly.  Given how often it is struck you can't blame them for erring on the side of caution and I think it is others who should be getting their house in order.

Edited July 17, 2021 by DY444

[jim.snowdon]

7 hours ago, SamThomas said:

As an example trhe one pictured is signposted at 13'6" - up untill a year or so ago I regulary drove HGV's that were 12'8" (actually measured & they had self leveling air suspension) so I knew they were well underheight.

However, the warning signs were tripped by every single vehicle in the fleet.

The Local Council, TfL, Network Rail & Highways Agency were all contacted & informed about the issue & none of them accepted responsibility for the problem or appeared to get it sorted.

 

I'm not condoning the actions of HGV drivers who strike bridges but the authorities need to get their house in order too.

If I was in NR's position, I don't think I would change it either. If the sign illuminates and causes an HGV driver to stop and think 'how high is my trailer' then it has done its job. If the answer, as in your case is a measured 12' 8", then you know you have clearance and can proceed. Where it fails (or rather is beyond its capabilities) is where a driver who hasn't measured his vehicle just carries on and discovers the hard way that his trailer was over 13' 6" after all.

Where it all falls down (not literally) is that the railway authority cannot erect a substantial crash beam at, say, 13' 3" that will stop/decapitate an overheight vehicle before it gets to the bridge. To do that requires joined up thinking between the railway authority and the highway authority, something that seems to be a rare commodity.

[SamThomas]

You both missed my point(s).

 

If the automatic signs "err on the side of caution" then human nature can then creep in so that some drivers will then think - "if the signage (including the automatic ones) say, e.g. 12'6" clearance then I will be OK for an extra 6" or so".

 

The clearance on this bridge has reduced over the years due to road resurfacing, hence my comment that the various authorities need to get their house's in order.

 

Clearly, something needs to be done here because with the amount of time this one gets bashed it's only a matter of time before there is a serious incident.

 

"substancial crash beams" cannot be errected in areas where there is pedestrian traffic. A better solution would be something like the hanging tubes/pipes in the Blackwall Tunnel.

 

Unfortunatly, these issues are a product of the age we live in now. The railway companies, when they built the railways did not envisage just how high HGV's would get in the publics quest for cheaper products - economies of scale.

 

FYI - it is part of a drivers daily walkround (for which 15minutes is allowed & should show on his tachograph record) to check the actual height of the vehicle. It is a;lso part of the checks to ensure that the height indicator in the cab is present & displays the correct height.

 

[jim.snowdon]

2 minutes ago, SamThomas said:

If the automatic signs "err on the side of caution" then human nature can then creep in so that some drivers will then think - "if the signage (including the automatic ones) say, e.g. 12'6" clearance then I will be OK for an extra 6" or so".

In other words, you can't win?

 

3 minutes ago, SamThomas said:

"substancial crash beams" cannot be errected in areas where there is pedestrian traffic. A better solution would be something like the hanging tubes/pipes in the Blackwall Tunnel.

Apart from the bridge itself, which is quite a substantial crash beam, NR have often erected beams just ahead of the structure so that the impact is not taken by the bridge itself. The existance of pavements, and therefore pedestrian traffic, under the bridge remains the same as if a crash beam were erected some distance back.

 

6 minutes ago, SamThomas said:

Unfortunatly, these issues are a product of the age we live in now. The railway companies, when they built the railways did not envisage just how high HGV's would get in the publics quest for cheaper products - economies of scale.

Very true.

 

Jim

[Edwin_m]

7 hours ago, jim.snowdon said:

Apart from the bridge itself, which is quite a substantial crash beam, NR have often erected beams just ahead of the structure so that the impact is not taken by the bridge itself. The existance of pavements, and therefore pedestrian traffic, under the bridge remains the same as if a crash beam were erected some distance back.

Unless the crash beam is very substantial indeed, there is a risk that an impact by a very solid vehicle such as a refuse collector would bring the beam down.  This might be much more lethal to nearby pedestrians or even those in other vehicles than hitting the bridge itself which is unlikely to shed large parts of its structure.  

Edited July 18, 2021 by Edwin_m

[DY444]

9 hours ago, SamThomas said:

You both missed my point(s).

 

If the automatic signs "err on the side of caution" then human nature can then creep in so that some drivers will then think - "if the signage (including the automatic ones) say, e.g. 12'6" clearance then I will be OK for an extra 6" or so".

 

The clearance on this bridge has reduced over the years due to road resurfacing, hence my comment that the various authorities need to get their house's in order.

 

 

I think the point is entirely straight forward.  The prohibition signs on both sides of the bridge make it illegal for any vehicle higher than 13' 6" to attempt to pass beneath it.  I don't see any basis at all for a driver to unilaterally decide that really means 14'.  The fact that you even say that rather gives the impression that this may be a common haulage industry practice and if so probably gives us a good idea why so many vehicles strike that bridge and others.  Almost all bridge strikes occur because of drivers not paying attention to the posted restrictions or by chancing it.  Any suggestion that overly cautious warnings are a factor doesn't pass muster imo.  In any event warnings are warnings, they do not remove the responsibility from the driver for ensuring that the posted prohibitions are complied with.

 

I'm not convinced either that you can reasonably complain about warnings being too cautious whilst simultaneously implying that resurfacing may result in the true clearance actually being less than the posted maximum.

Edited July 18, 2021 by DY444

[Michael Hodgson]

2 hours ago, Edwin_m said:

Unless the crash beam is very substantial indeed, there is a risk that an impact by a very solid vehicle such as a refuse collector would bring the beam down.  This might be much more lethal to nearby pedestrians or even those in other vehicles than hitting the bridge itself which is unlikely to shed large parts of its structure.  

The crash beams on bridge 102 are indeed very substantial.  An additional brick abutment was built butting up to the existing  bridge supports on both sides of the road and on both sides of the line.  Firmly secured at the top of that is a massive  steel girder.  I presume its height is about an inch less than the lowest part of the bridge deck.  When a curtain sided trailer hits the beam, the thing comes out diamond-shape.  I have also seen a strong overheight load hitting the girder. The load in question was a steel digger bucket shaped a bit like a ship's anchor with a rigid support arm projecting upwards and forwards at about 45 degrees to the flatbed trailer it was chained to.  The lorry speed was not that great because there is a roundabout immediately after the bridge.  The lorry stopped dead.  The warning notices fastened to the girder fell off but the beam withstood the impact.  The bridge carries the ECML and trains on the fast are doing 125.  Any incursion into the bridge would hit the Up siding and the Up Slow before the Up Fast  was affected (for some reason most strikes on this bridge seem to be by lorries going West).  In the other direction the Down Fast is shielded by the Slow 

[Clive Mortimore]

Not only in the UK that drivers think the warning signs apply to others, not them. Willem has made a whole You Tube channel of events at the "Canopener Bridge".

 

[SamThomas]

Jim.

Unless a lot of infratructure is changed it will be a lose/lose all round.

My point about the crash beams is that they cannot be errected if pedestrians or other road users could be inured by debris from vehicles or (as pointed out by Edwin) or from the crash beam itself (FYI a refuse truck is a very substancial bit of kit). Unfortunatly, this risk will always remain regarding the bridge itself.

 

Edwin.

Agree tottaly.

 

DY

Unfortunatly, HGV (& other drivers) are under a lot of pressure & that's how large segments of the haulage/logistics industry is (see my comment at the end). Personally, I never worked for such companies. I do not condon HGV drivers for bridge bashing. However, signage simply must be accurate & drivers must know the height of their vehicle.

The particular bridge pictured was resigned some time ago when it was remeasured & found that the clearance had been reduced over the years by resurfacing.

Of course if the signage "errs on the side of caution" and all "overheight" HGV's divert (often onto roads even more unsuitable for HGV's) with the resultant increase in journey times & pollution.

 

Michael.

I'm not familiar with Bridge 102 but do see your points.

Curtainsider bodies are very flimsy & often used on multi-drop where the height of the vehicle does increase as the days duty progress' - not all vehicle have self levelling suspension.

 

General.

I'm not condoning bridge bashing at all - I'm just trying to point out some of the reasons it happens.

Now, if HGV drivers had & followed a rule book like train drivers (& were in the same salary scale) bridge bashing would be a very, very rare occurance.

The haulage/logistics industry is one of the most competative (& in some areas, noteably the parcels section) poorly regulated industies that we all depend on.

If you are on multi-drop pallet work & could comfortably cover 12 drops you will get 14 & be expected to put your tacho onto "break" when unloading.

Parcels delivery drivers are expected to cover 70 or 80 drops/pickups per shift - that could mean a drop/pickup every 6.5minutes - as for breaks - forget it (good job they are not subject to HGV/PCV drivers hours).

Inattension is a huge factor & can be caused by tiredness &/or pressure to get the job done/back to base for another driver to use the vehicle. (see below)

 

& who is to blame for this ? Yes, that's right, us, the consumer. We are indirectly part of the problem - we want it tomorrow, we want delivery for "free" or at minimal cost.

So, next time you want something from that great river just spare a little thought for the poorly paid people in the supply chain, warehouse staff, the HGV driver who works nights, the people in the local(ish) distribution centre who get up everyday at "stupid-o-clock", the guy in his Sprinter who does not get a break during his working day or (at the bottom end) the guy in his (possibly uninsured) borderline MOT case vehicle nursing it through the day.

It would be so simple to change this - pay drivers a decent wage (whatever you do for a living would you do it ?), less deiveries per shift (but then that means more vehicles). But of course the "free" deliveries would go & the costs of other deliveries would go up.

 

I repeat, I'm not condoning unprofessional driving (which is why I have been lucky enough to only drive for the few & far between responsible companies), just trying to point out some of the reasons these things happen.