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Post by Deleted on Apr 5, 2013 3:29:00 GMT
Warning: LONG - covers a bit of ground ("Rambling" as Crusty54 might put it)
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I have spent the best part of a day searching the archives of DD's, through many a locked thread. I found a number of Moderator references to relocating a thread to "New and Future Rolling Stock" - but that was on the OLD webiste/server. So, firstly, how do I find those threads?
Secondly, I was seeking to dig into an apparent paradox that claims that the 09ts is larger than other ts, and can't pass through the Picc line, hence road delivery.
I've found that, based on TfL and TubePrune's information:
1967/72ts w: 2641; frame ht: 756; roof ht: 2875; l: 15977 & 16091
1973 ts w: 2629; frame ht: 730; roof ht: 2888; l: 17473 & 17676
1992 ts w: 2620; frame ht: 690; roof ht: 2869; l: 16248 * - solebar ht based on diagram, may be misread.
1995 ts w: 2630; frame ht: 750; roof ht: 2875; l: 17770
1996 ts w: 2629; frame ht: 750; roof ht: 2875; l: 17770
2009 ts w: 2609; frame ht: 690; roof ht: 2883; l: 16345 & 16595
So, on the face of it, the 2009ts is the NARROWest of all current/recent stock, it's not the tallest and it's 5mm LOWER than Piccadilly line stock; it's the 3rd shortest, so the ONLY dimension that seems to be critical is the Frame or Solebar height, which at 690mm is the LOWEST.
Perhaps it's this that fouls the Piccadilly tunnels? The Vic tunnels IIRC were built to 12'0" (3657mm) minimum dia (some to 12'6"), the Picc to 11'8 1/4" (3562mm).
BTW, what this means is that the 09ts is only more spacious in the sense that it has more standing headroom, and that at 133275mm, the train overall is longer - with 2 fewer cabs. That means there is more floor space and more headroom, but in narrower cars.
What brought this to a head for me was a photo posted online that showed a gentleman seated in a perimeter seat of an 09ts. His knees were more than half-way across the car. Now, if there were four or five such gentlemen sitting opposite each other, the gangway would have been completely blocked. That got me checking dimensions. It also shows that the assumption that perimeter seating allows a better (as distinct from more) standing capacity may be flawed. There seems to be a platform dwell factor that correlates with population height (or more particularly, thigh bone length). Just another ergonomic/anthropometric challenge for the designers!!
Delivery: the 67ts was delivered through a temporary BR link at Northumberland Park. I can't imagine why that process wasn't used for the 09ts, or indeed why a permanent siding can't crest a gradient at the height of the protection levee at NP? (Unless the devil was cost ... ?)
ARTICULATION, CAR LENGTHS, BOGIE TURNING, CAR WIDTHS and other EXCITING THINGS
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There was a whole lot of discussion on the locked threads about the EVO concept and so on.
Here's an interesting statistic. There are basically (AIUI) two notionally standard tube platform lengths: 350' (106.680m) and 425' (129.540m). The difference is roundly 22m. If car pairs 22m long over coupling faces were used, we would have 110m and 132m trains, which with trailing cabs and some saloon in tunnel, would fit both the shorter and longer platforms with a standard stock. The cars being short, and assuming short wheelbase bogies at the outer extremities with smaller wheels (e.g. 600-650mm), would fit any tube line. In other words, a Universal tube stock. The make up would be +(DM-M)+(M-M)+..+(M-M)+(M-DM)+ where + is a coupling point and - is a bar link. The coupling points are mechanical only Wedgelock, and can be used at depot level to separate a faulty sub-unit. Spares would be +(DM-M)+.
Now, to make the weight manageable, and to reduce the number of bogies which allows more underfloor equipment space, each " - " link would be articulated. Again, following the arguments used about the EVO and the Siemens uglimobile, it would seem that if walk through gangways are desired, they can't be above a bogie (I don't actually follow why, it would seem to be eminently sensible to me). But if this is still the case, then maybe we have a 12.5m car with 2 bogies supporting at one end a 9.5m car with one. Either way works, though the uneven lengths means finding a way to optimise door positions a bit more challenging. A single leaf door may be needed. With six 22m sub units each with 3 bogies replacing eight cars with 2 bogies, we end up with 18 bogies vs 16.
1800mm doors were proposed, and there were comments about this being enough for triple streams. This would work only as zip-streams (from anthropometric data which would be the best case in human behavioural terms), which means each stream is interdependent and vulnerable to disruption. 1600mm allows generally autonomous double streams. I suspect 2m or 2.1m is needed for triple autonomous streams - a factor I have included in my DD designs. 1800mm would be useful on a line where luggage is a frequent factor, but only for double streams.
Finally, from Graham Hewitt's comments on the RIPAS threads, it seems that W&C can be extended to about 82-ish metres, or 98-ish metres or more if the travelator was removed and replaced by escalators replacing the stairway. This potentially could allow a 4 subunit, 88m train for the W&C.
As I see it, the Universal cars could be around 2650mm wide at seated shoulder height, have a floor height of 600mm, have small wheel housings about 640mm in from the sides (probably to be used in conjunction with some transverse seating), an overall height of 2870mm. I'd use saloon windows the same height as the 1938-67 stocks, which I think was the right height for checking platform names for both seated and standing passengers, and door windows that are higher. The coupling ends would also be gangwayed through with a pressure seal.
The U cars would have full regenerative braking, "last mile" capability (enough battery capacity to get home in event of total supply failure), max speed of 120km/h (to justify fettling up the longer open air plain line sections), and be air conditioned. Lightweight composites would be used as much as possible, and light, high tensile steels and strong aluminium alloys elsewhere. I expect permanent magnet AC induction motors and use of some underseat space for equipment. All U trains would have cabs at the ends, only. These could serve either for drivers or as "train captain's offices" - but whichever way they end up being used, there WOULD be cabs. The units would be fitted with ATO equipment compatible with all systems used on LU tracks, so that stock rebalancing is a straightforward matter. From day 1, they would have the capability to run on 750/850v DC 3rd rail (only) lines via a traction supply switch that could be auto linked to balises at changeover points (noting the AC-DC changeovers used on full gauge operations). Their suspension would be able to lift the cars from 600mm floor height to 840mm floor height to enable level boarding at "compromise" height platforms. Whether the extra 75mm to reach UK standard 915mm is feasible, on top of 240mm, I don't know. If it is, then it should be incorporated. "Gap filler" flaps or extension plates would be developed and incorporated.
In this manner, the cars can readily operate on NR DC tracks, and may be useful as traffic and engineering spares for some LO operations, to reduce overall fleet size. The design should be phyically and mechanically compatible with all* LU lines, the only difference between being a matter of software. The design should be such that batches could be built by multiple manufacturers with standardised interfaces at several levels - to simplify both operations and maintenance. It also means that LU becomes less dependent on a single supplier for a particular route.
* - How the doors could be made to align with the Platform Edge Doors on the Jubilee is one issue I think would be intractible. From the data to hand (and this was discussed without resolution on the locked threads), it seems prima facie that 1995 and 1996 stock could both work the route, but that the 1995 stock would need a refurb and mod to facilitate that; and the 95ts would need to be kept and managed as a separate fleet. So the Northern would get some U stock and cascade some 95 stock via the works to the Jubilee, which would remain "locked in" with its PEDs for the interegnum.
That should be enough for DD's afficiandos to chew on
Regards
DW down under
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Post by Deleted on Apr 5, 2013 9:17:24 GMT
Secondly, I was seeking to dig into an apparent paradox that claims that the 09ts is larger than other ts, and can't pass through the Picc line, hence road delivery. ISTR that the first '09 stock train did come by rail via the Picc. The impression I had was that the problem was rather than not fitting, the '09 stock didn't have the Picc line compatibility box ticked, in an era of line independence this wasn't worth doing so it had to be towed in engineering hours - and that as 'the other' PPI contractor had the Picc deal they weren't going to give up some of their time to help their competitors who had the Vic deal. But getting back to the main topic of the thread, whatever the merits (and however many there are) of 'universal' stock (which was the norm for the unified tube system until relatively recently), current thought is that each line should be on its own, with its own standards and (non-transferable) stock. |
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Post by Deleted on Apr 5, 2013 9:45:23 GMT
Air conditioning? On tube trains? Well, if a possible groundwater system is installed above the tunnels to take up the heated air (or something similar), then it could work... All U trains would have cabs at the ends, only. These could serve either for drivers or as "train captain's offices" - but whichever way they end up being used, there WOULD be cabs. So cabs will be in place. Will Half cabs be possible, like NY Subway cars, or will it be full-size cabs? Then again, they could have windows on the bulkhead, like here: [Clicky] but I doubt it. From day 1, they would have the capability to run on 750/850v DC 3rd rail (only) lines via a traction supply switch that could be auto linked to balises at changeover points (noting the AC-DC changeovers used on full gauge operations). This sounds interesting... Not exactly how the 3rd/4th rail shoes will act to this (seperate bogie traction systems?) What I mean is that ALL bogies will be powered, but half of them will have traction equipment for 4th rail (i.e. middle rail shoes etc.) and the other half for 3rd rail. 3rd/4th rail shoes that can lift out of the way of the different traction systems (so when the train is on 3rd rail, the 4th rail shoes will lift out of the way v/v).
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Post by Chris M on Apr 5, 2013 10:55:38 GMT
Why is such a complicated system needed re shoes? D stocks run perfectly happily on third rail supply when there is a fourth rail present (Richmond branch). Providing that has got to be cheaper and more reliable than two traction systems on every train. If you want to interrun on any third rail system then would it not be a better bet to convert the tube to third rail?
Also I seriously doubt there is space beneath a tube car for all these powered bogies, gap fillers, adjusting suspension and all the associated equipment (remember you'll need beefy compressors just for your suspension as well as the existing set). Can all this equipment be made reliable? One suspension adjuster failing could cause force an entire train out of service. If it failed in the "up" position it may even be unable to get home to a depot. Metro stock needs to be very reliable - I recall that plug doors were considered for the S stock but no manufacturer was able to give the reliability levels required.
Have you considered the weight issues of all this equipment? Heavier trains need more power to move and produce more wear on the track (and so lead to increased maintenance costs).
Consider that LO didn't think it value for money to make all their 378s dual voltage.
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Post by bassmike on Apr 5, 2013 12:16:00 GMT
As I have said before, I fail to understand why LU has not converted to third rail only long ago. It would save endless needless complications, and allow access anywhere by anything if needed plus more flexible interworking without 3/4 rail power change equipment.(Obviously apart from allowing full-size stock to enter the small diameter tubes).Also , call the whole lot TfL if you must this would stop the ridiculous anomalies of "Underground " stations miles out in the country like Chesham and Epping Etc; and "Overground stations in tunnel below ground like Whitechapel Wapping Rotherhithe etc: I have often heard opinions like this from people who travel to lLondon from other countries, but here, if you have no unwanted complications, you have to invent them. Secondary advantages would be hundreds of miles of fourth rail not needing maintainence, and the re-usable use as third rail or scap value if not. Un fortunately this is England.
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Post by Deleted on Apr 5, 2013 12:47:00 GMT
Warning: LONG - covers a bit of ground ("Rambling" as Crusty54 might put it) ================================================ I have spent the best part of a day searching the archives of DD's, through many a locked thread. I found a number of Moderator references to relocating a thread to "New and Future Rolling Stock" - but that was on the OLD webiste/server. So, firstly, how do I find those threads? Secondly, I was seeking to dig into an apparent paradox that claims that the 09ts is larger than other ts, and can't pass through the Picc line, hence road delivery. I've found that, based on TfL and TubePrune's information: 1967/72ts w: 2641; frame ht: 756; roof ht: 2875; l: 15977 & 16091 1973 ts w: 2629; frame ht: 730; roof ht: 2888; l: 17473 & 17676 1992 ts w: 2620; frame ht: 690; roof ht: 2869; l: 16248 * - solebar ht based on diagram, may be misread. 1995 ts w: 2630; frame ht: 750; roof ht: 2875; l: 17770 1996 ts w: 2629; frame ht: 750; roof ht: 2875; l: 17770 2009 ts w: 2609; frame ht: 690; roof ht: 2883; l: 16345 & 16595 So, on the face of it, the 2009ts is the NARROWest of all current/recent stock, it's not the tallest and it's 5mm LOWER than Piccadilly line stock; it's the 3rd shortest, so the ONLY dimension that seems to be critical is the Frame or Solebar height, which at 690mm is the LOWEST. Perhaps it's this that fouls the Piccadilly tunnels? The Vic tunnels IIRC were built to 12'0" (3657mm) minimum dia (some to 12'6"), the Picc to 11'8 1/4" (3562mm). BTW, what this means is that the 09ts is only more spacious in the sense that it has more standing headroom, and that at 133275mm, the train overall is longer - with 2 fewer cabs. That means there is more floor space and more headroom, but in narrower cars. 09 Stock never got gauge clearance for the Picc Line. The external dimensions above are not the only critical dimensions for gauging purposes - it is the kinematic envelope rather than the static envelope that matters. You also need to consider things such as wheelbase (bogie centre to bogie centre), which governs the amount of centre throw and end throw when working out a vehicles 'kinematic envelope'. Don't have all of the figures to hand, but I'm sure an 09 Stock kinematic envelope will be larger than a 73's, hence it never getting clearance for the Picc Line (gauging runs would have been required). |
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Post by Deleted on Apr 5, 2013 12:48:52 GMT
I don't get why this new EVO thing has to be so over complicated and evolutionary as the name suggests. I highly doubt it will work out of the box if it even gets out of the box. Why can't LU do anything sensible that works ever since the late 80's?!
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Post by Deleted on Apr 5, 2013 12:52:19 GMT
All U trains would have cabs at the ends, only. These could serve either for drivers or as "train captain's offices" - but whichever way they end up being used, there WOULD be cabs. So cabs will be in place. Will Half cabs be possible, like NY Subway cars, or will it be full-size cabs? Then again, they could have windows on the bulkhead, like here: [Clicky] but I doubt it.i][/quote] I enjoy this view far more than I should do at the moment! Only for another week  |
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Post by domh245 on Apr 5, 2013 13:06:07 GMT
I quite like the idea of having half cabs, so you can see out of the cab. Perhaps something like the croydon Variobahns would be good , see here, or potentially something like the DB ICE 3s |
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Post by Deleted on Apr 6, 2013 5:31:03 GMT
Warning: LONG - covers a bit of ground ("Rambling" as Crusty54 might put it) ================================================ I have spent the best part of a day searching the archives of DD's, through many a locked thread. I found a number of Moderator references to relocating a thread to "New and Future Rolling Stock" - but that was on the OLD webiste/server. So, firstly, how do I find those threads? Secondly, I was seeking to dig into an apparent paradox that claims that the 09ts is larger than other ts, and can't pass through the Picc line, hence road delivery. I've found that, based on TfL and TubePrune's information: 1967/72ts w: 2641; frame ht: 756; roof ht: 2875; l: 15977 & 16091 1973 ts w: 2629; frame ht: 730; roof ht: 2888; l: 17473 & 17676 1992 ts w: 2620; frame ht: 690; roof ht: 2869; l: 16248 * - solebar ht based on diagram, may be misread. 1995 ts w: 2630; frame ht: 750; roof ht: 2875; l: 17770 1996 ts w: 2629; frame ht: 750; roof ht: 2875; l: 17770 2009 ts w: 2609; frame ht: 690; roof ht: 2883; l: 16345 & 16595 So, on the face of it, the 2009ts is the NARROWest of all current/recent stock, it's not the tallest and it's 5mm LOWER than Piccadilly line stock; it's the 3rd shortest, so the ONLY dimension that seems to be critical is the Frame or Solebar height, which at 690mm is the LOWEST. Perhaps it's this that fouls the Piccadilly tunnels? The Vic tunnels IIRC were built to 12'0" (3657mm) minimum dia (some to 12'6"), the Picc to 11'8 1/4" (3562mm). BTW, what this means is that the 09ts is only more spacious in the sense that it has more standing headroom, and that at 133275mm, the train overall is longer - with 2 fewer cabs. That means there is more floor space and more headroom, but in narrower cars. 09 Stock never got gauge clearance for the Picc Line. The external dimensions above are not the only critical dimensions for gauging purposes - it is the kinematic envelope rather than the static envelope that matters. You also need to consider things such as wheelbase (bogie centre to bogie centre), which governs the amount of centre throw and end throw when working out a vehicles 'kinematic envelope'. Don't have all of the figures to hand, but I'm sure an 09 Stock kinematic envelope will be larger than a 73's, hence it never getting clearance for the Picc Line (gauging runs would have been required). Of course, the kinematic envelope matters. End throw: 73ts: 3276mm; 09ts: 3245mm, 3125mm. The 09ts has less end throw than 73ts. Bogie centres: 73ts: 11124; 09ts: 10095. The 09ts has closer bogie centres than 73ts. So, the 09ts must have VERY, VERY sloppy suspension (much more freedom on each degree of freedom) compared to 73ts. That's certainly not been a comment I've seen expressed on any forum. There was a gauging run. Would be nice to know the outcome, but we didn't hear of new train stuck in Piccadilly Line tunnel, did we? I think you're wrong about kinematic envelope. But the fact that the stock did not have gauge clearance, and that two competing businesses were running what should have been ONE network probably explains why. Back to the old Met vs District balderdash again. London doesn't need it, the Mayor knows that and is fixing it (despite his political label). |
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Post by Deleted on Apr 6, 2013 5:46:01 GMT
Secondly, I was seeking to dig into an apparent paradox that claims that the 09ts is larger than other ts, and can't pass through the Picc line, hence road delivery. ISTR that the first '09 stock train did come by rail via the Picc. The impression I had was that the problem was rather than not fitting, the '09 stock didn't have the Picc line compatibility box ticked, in an era of line independence this wasn't worth doing so it had to be towed in engineering hours - and that as 'the other' PPI contractor had the Picc deal they weren't going to give up some of their time to help their competitors who had the Vic deal. I tend to agree with you. I think it is now clear that a re-unified LU wants to avoid the lock-in problems of dedicated stock. The EVO work was a longer term planning exercise and represented senior management thinking. Independent lines require an overall higher level of stock because synergies in engineering and traffic spares cannot be realised, and the benefits of new stock designs and technologies inaccessible until complete line renewal. LU had no real problems with the 38ts being the foundation (with the 49ts extension order) of the bulk of the network's trains - with some specially adapted cars for specific lines. I think the aim is to get back to that place. The Vic '09 design, as I've shown, isn't really that radical in making use of the larger VL tunnels. I was actually very dismayed to read the hard numbers when compared to the promo balderdash. It does nothing with the Vic tunnels that couldn't be done on the others, save perhaps the Central - and even the Central has the same 690mm high solebar with wider cars! So far, I've found NOTHING that justifies the claim that the 09ts makes better use of the VL tunnels and the cannot be used on other lines. The only thing done is the trains are LONGER overall, by a few metres. That's got nothing to do with the tunnel diameter, but all to do with a generous stopping margin allowed for a 1st generation ATO system. |
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Post by Deleted on Apr 6, 2013 6:17:34 GMT
Air conditioning? On tube trains? Well, if a possible groundwater system is installed above the tunnels to take up the heated air (or something similar), then it could work... You haven't read the old threads, have you? All the work centres on lighter trains made up of lighter components including lighter permanent magnet AC induction traction motors, lighter more efficient traction control modules, with fully functioning regenerative braking which requires the electrical system to handle voltages close to 800v DC (possibly more). Composites for the body. The argument is that the reduction in heat from motoring the train (more efficient equipment pushing a lighter load) and almost complete elimination of waste heat from braking, coupled with current work to improve air flow by upgrading ventilation plant should be sufficient to allow air conditioning to be incorporated. Groundwater tunnel cooling seem to me to be a no-brainer, but something seems to be holding it up. Any ideas what, other than politics and funding? That ultimately would be determined by future negotiations. Cabs would be modular, so that the appropriate set up for the day, for the line, could be implemented. Half cabs are certainly conceivable, given adequate DOO displays - but there's nothing quite like a look down the platform just to be sure, is there? No. All wheels will be powered from the DC fed traction control modules. A brief and simplified lesson in DC circuits here: DC can have a positive +ve voltage and a negative -ve voltage. The actual potential difference is the sum of those. Normally, in a single conductor supply system, "earth" is the return conductor, so the potential difference IS the voltage on the single supply = 750v DC for example, or 25kV AC. But, if the supply has two conductors, then you can have half the total voltage on each or some mix thereof. This reduces the potential difference between the supply and earth, reducing risks of electrocution, flashovers and more importantly, stray return currents passing through the cast iron linings of tunnels and other conducting material nearby. By having dual conductors, and lower voltage on each, the LU system reduces corrosion on nearby conducting materials. This was a real concern in the late 1890s/early 1900s because of the fear of damages claims. So the +420/-210 (sometimes shown as +415/-215) system came eventually into use. If you are using a 2 conductor system, and wish to co-work with a 1 conductor system, all that is required is to put the full voltage on one conductor and tie or bond the other to "earth." That's what happens out towards Richmond, north of Queens Park, etc. All the switch I propose does is to link the 4th rail shoe pickup circuit with the earth link through the wheels. This is a straight circuit breaker, and it means that a 4th rail bonded to the "earth" rail is no longer needed for through operation. Note please that only one rail is the "earth" rail in any track-circuited track, because the other is the "live" side of the track circuit voltage. That's why the WCML has been changed to an axle-counting system: to improve continuity of the "earth" side of the supply circuit by allowing BOTH rails to be bonded together and to "earth". |
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Post by crusty54 on Apr 6, 2013 7:27:15 GMT
short memories here. 73 stock scraped the tunnels on delivery. had to use revised handrails over the doors to reduce the height.
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Post by Deleted on Apr 6, 2013 9:02:09 GMT
Why is such a complicated system needed re shoes? .....
Prepared response offline. Hope is clear ....
Why is such a complicated system needed re shoes?
What’s complicated? A circuit-breaker between the 4th rail circuit and “earth” via the wheels? Circuit breakers – well tried, tested, proven.
D stocks run perfectly happily on third rail supply when there is a fourth rail present (Richmond branch). Providing that has got to be cheaper and more reliable than two traction systems on every train.
I’m broadly aware of how the 4th rail voltage is stepped down in stages from -215vDC to -0vDC. The circuit breaker suggested allows the 4th rail to be removed on such former dual system sections.
There is ONLY ONE traction system in the EVO concept and in my iteration of it. DC traction supply from whichever source feeds solid state traction control modules in turn feeds permanent magnet AC induction traction motors. All motors are operational under all operating scenarios, fault isolation aside
If you want to interrun on any third rail system then would it not be a better bet to convert the tube to third rail
Interesting point. Let’s review. As I pointed out above, the dual conductor system was adopted to limit the stray (eddy) currents from the putative LU affecting conducting material in the vicinity – to minimise the risk of litigation, damage to railway structures and corrosion of cast iron linings.
However, the GN&C has now run on “earth” return for 37 years and I’m not aware of any adverse consequence. The W&C ran for nearly 100 years with “earth” return. Likewise, I’m not aware of any adverse consequences.
So, yes it appears prima facie that LU could convert to single conductor supply, but bear in mind the other factors: lower (but still real) risk of electrocution, and reduced risk of flashovers.
Under present arrangements, it would have to be a 2-stage process tied in with rolling stock renewal. The first stage, gradually bonding the 4th rail to “earth” as the traction supply for each section is modified. When that is complete, the 4th rail is still in use but now at -0v (ie “earth”) and bonded to a running rail. Then when new rolling stock has completely replaced the old, the 4th rail can be removed.
With the U stock in place, the rolling stock can handle either supply, so the 4th rail can be removed as soon as the power supply is modified/upgraded. It no longer needs to be maintained.
Also I seriously doubt there is space beneath a tube car for all these powered bogies, gap fillers, adjusting suspension and all the associated equipment (remember you'll need beefy compressors just for your suspension as well as the existing set).
As far as the traction and air conditioning equipment, the EVO teams and Siemens were in NO doubt.
The gap fillers and ride height adjustment are new. They would probably be cam driven with electric and hydraulic/pneumatic motors (for redundancy).
I don’t see them as needing a huge amount of space, but the ride height system will need some high tensile steel framing and “pantographic” type assemblies to keep everything stable and aligned. That is extra weight. We’d need input from folks with access to engineering design software to help us on this one.
The gap filler replaces the existing steps, just allows them to slide in and out and perhaps a bit of angular swing. Not a lot to it, and designed as a frangible component so as to not be mission-critical.
Can all this equipment be made reliable? One suspension adjuster failing could cause force an entire train out of service. If it failed in the "up" position it may even be unable to get home to a depot. Metro stock needs to be very reliable - I recall that plug doors were considered for the S stock but no manufacturer was able to give the reliability levels required
Plug doors are not used on LU because they can’t be made fast enough for tight dwell time metro operations. Also, manufacturers are risk averse and were not willing to commit to reliability levels required in the specification, with the risk of litigation.
In terms of doors, I’m considering use of a non-straight door guide, similar to the system used for many years in the demanding commercial applications of vans and minibuses – like the side doors of a Toyota HiAce Commuter (consider those in taxi service). This system would have to be designed to keep the door very close to the body side. For gauging purposes, an open door would be regarded as “frangible.” If a door fails in the open position, the train will be taken OOS and worked back to a depot ASAP. The extra width should be within the kinematic tolerances, especially with an empty train run at reduced speed – and if it scrapes a layer of paint here and there, is not going to stop operations.
The ride level system. I’ve already indicated that I’d look for at least dual redundancy here, to raise reliability levels. However, I’d contend that a failure would be an order of magnitude less frequent than door failures causing a train to be taken OOS. This is because the public does not interact with the ride height equipment, but they do with the doors. The plan is to activate the lowering to tube height BEFORE the last turnout prior to the tube portal. If a failure should occur, the train would be diverted to a surface line station where it can terminate (eg from Kensal Green, a southbound Bakerloo failure would divert to the DC lines Up platform at Queens Park and continue to terminate at Euston).
But I do expect that suitable sections of line will see quite intensive use during the prototyping process. The Roding Valley line comes to mind. An off-peak Chesham shuttle? W&C, Kensington Olympia? Woodford – Epping off peak
Have you considered the weight issues of all this equipment? Heavier trains need more power to move and produce more wear on
the track (and so lead to increased maintenance costs)
Yes. And so have the EVO designers and Siemens. They are sure that it can work. Now I have added to the equipment the “gap fillers” (I should call them “active step plates”, it sounds more technical!) and the ride level adjusters. These will add to the weight that the EVO and Siemens teams were calculating. However, these trains will be lighter on the track than existing trains, whatever happens. That’s the design task.
Consider that LO didn't think it value for money to make all their 378s dual voltage
Quite rightly so! As long as ALL the engineering and traffic spares that are provisioned are dual voltage, there is no risk to having a dedicated DC sub-fleet. The DC sub-fleet would be cheaper to acquire and maintain. It makes every economic sense to do so.
I expect that the U stock allocated to a line (without any engineering or traffic spares) would have only the features needed. But the spares would be fully-featured and come from a shared pool.
Examples of lines that do not or should not need ride level control include Victoria and Jubilee. On the other hand, these will be the LAST to receive new stock. The Victoria because it has just been re-equipped, and I am assuming that the 09ts will have a better track (hmmm!!) record than the 83ts. The Jubilee because it has PEDs (Platform Edge Doors). To provide for future growth on the Jubilee, I expect the 95ts by virtue of having doors that AFAIK align with the Jubilee PEDs, to be adapted to suit. They would be managed and maintained as a separate fleet due to the many differences between them and the 96ts. To replace them, the Northern would receive U stock.
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Post by Deleted on Apr 6, 2013 9:04:17 GMT
As I have said before, I fail to understand why LU has not converted to third rail only long ago. It would save endless needless complications, and allow access anywhere by anything if needed plus more flexible interworking without 3/4 rail power change equipment.(Obviously apart from allowing full-size stock to enter the small diameter tubes).Also , call the whole lot TfL if you must this would stop the ridiculous anomalies of "Underground " stations miles out in the country like Chesham and Epping Etc; and "Overground stations in tunnel below ground like Whitechapel Wapping Rotherhithe etc: I have often heard opinions like this from people who travel to lLondon from other countries, but here, if you have no unwanted complications, you have to invent them. Secondary advantages would be hundreds of miles of fourth rail not needing maintainence, and the re-usable use as third rail or scap value if not. Un fortunately this is England. Covered in my response to Chris M, Quizmaster. |
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Post by Deleted on Apr 6, 2013 9:44:57 GMT
short memories here. 73 stock scraped the tunnels on delivery. had to use revised handrails over the doors to reduce the height. Those handrails being for maintenance staff to clean the windscreens, displays and lamps - yes? At the very extremity of the vehicle? No surprises there, really? |
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Post by crusty54 on Apr 6, 2013 9:47:23 GMT
short memories here. 73 stock scraped the tunnels on delivery. had to use revised handrails over the doors to reduce the height. Those handrails being for maintenance staff to clean the windscreens, displays and lamps - yes? At the very extremity of the vehicle? No surprises there, really? no they were the internal handrails above the doors which had to be changed and the roof had to be pulled down be surprised |
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Post by Deleted on Apr 6, 2013 10:19:25 GMT
Those handrails being for maintenance staff to clean the windscreens, displays and lamps - yes? At the very extremity of the vehicle? No surprises there, really? no they were the internal handrails above the doors which had to be changed and the roof had to be pulled down be surprised Where's this recorded. Is there an online reference? Surely it would have been a big issue back then. Let's clarify, which doors? Every passenger door? Or those at car ends, where there is a lot of throw? And meanwhile, what's your take on the EVO work and the Siemen's Uglimobile? |
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Post by crusty54 on Apr 6, 2013 10:26:48 GMT
it was a big issue at the time. Centre doors. The trains arrived lighter than expected and did not 'sink' as much as thought.
Strange when you look at facts rather than fantasies.
There are more manufacturers than Siemens.
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Post by Deleted on Apr 7, 2013 7:02:49 GMT
it was a big issue at the time. Centre doors. The trains arrived lighter than expected and did not 'sink' as much as thought. Strange when you look at facts rather than fantasies. There are more manufacturers than Siemens. None of the descriptions of the 73ts (incl Tubeprune IIRC) make reference to this. Were you an "insider" at the time? Would love more facts - perhaps you could be more forthcoming? I arrived in Britain in '77 to study for my MSc. Whatever clamour there had been, had died down by then. Siemens were the only player to show their hand on EVO. The others (Bombardier and Alstom IIRC) did not go public. But I agree, there are more. Hitachi for one, then a host of Europlayers, and other Asian players. Sure. There's even Australian builders, to stretch a point <BOING>! But, there's only the EVO team's presentation and the Siemens' presentation to inform us (outsiders) at this stage. Thank goodness the 73ts was sorted out. |
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Post by d7666 on Apr 11, 2013 21:30:32 GMT
Modern trains are no longer built fixed to one or or other supply system.
The savings in not having a fully dual voltage fleet are marginal, thats not to say not worth doing, but probably marginal enough for the bean counters to consider it as a Capex saving. I personally doubt it is a whole life Opex fleet saving because I suspect they could get away with one less unit overall if they were all the same.
All VVVF technology trains ... thats those with contemporary traction packs and AC motors ... are independent of traction supply system and can very easily be converted between AC or DC or both.
Inside what happens is that either 750 V DC or 25 kV AC is converted to the HVDC link - not sure what it is in 378s but probably around 3000 V, converted again to VVVF (Variable Voltage Variable Frequency) AC to drive asynchronous motors, all done by electronics.
Apart from the transformer, alterations are minimal and rapid, a pantograph is peanuts in todays scheme of things.
The days of DC with resistor control and AC with tap changers, are long gone.
The same traction /principles/ apply to S stock, the only thing here is that S stock bodies are not provisioned with pantograph wells nor underframes for transformers. But S stock could very easily have been built run off 25 kV if say there were some sort of transport coordination in this country and Chilterns lines were soon to be wired, and if someone fitted a couple of sets of points around West Hampstead, and so on.
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Nick
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Post by Deleted on Apr 13, 2013 5:23:50 GMT
Modern trains are no longer built fixed to one or or other supply system. The savings in not having a fully dual voltage fleet are marginal, thats not to say not worth doing, but probably marginal enough for the bean counters to consider it as a Capex saving. I personally doubt it is a whole life Opex fleet saving because I suspect they could get away with one less unit overall if they were all the same. All VVVF technology trains ... thats those with contemporary traction packs and AC motors ... are independent of traction supply system and can very easily be converted between AC or DC or both. Inside what happens is that either 750 V DC or 25 kV AC is converted to the HVDC link - not sure what it is in 378s but probably around 3000 V, converted again to VVVF (Variable Voltage Variable Frequency) AC to drive asynchronous motors, all done by electronics. Apart from the transformer, alterations are minimal and rapid, a pantograph is peanuts in todays scheme of things. <SNIP> -- Nick Thanks Nick (D7666) for the briefing on moderrn solid state traction elelctronics. I'd covered the issues in my post: Consider that LO didn't think it value for money to make all their 378s dual voltage
Quite rightly so! As long as ALL the engineering and traffic spares that are provisioned are dual voltage, there is no risk to having a dedicated DC sub-fleet. The DC sub-fleet would be cheaper to acquire and maintain. It makes every economic sense to do so.
The 378s without AC capability must cost less than those with. By omitting the pan and tran cuts first cost and weight. It makes sense, but is future proofed by being retro-fittable. The point is that you treat the whole fleet as one, define the operational requirement, then add a traffic and engineering spares requirement. The latter I suggested must be dual voltage. In that way, one set of spares covers two sub-fleets and can reduce the number of spares otherwise needed by one or two units - not to be sneezed at. There's NO need to make the whole fleet dual voltage.
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Post by d7666 on Apr 13, 2013 19:03:17 GMT
Ahh yes I see I skipped over too much of your post, sorry.
But I bet there are a good many readers out there unaware of how easy these things are today ... I know the lack of awareness is there as this matter comes up over and over again on other, non-LU, forums.
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Nick
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Post by Deleted on Apr 14, 2013 8:07:09 GMT
Modern trains are no longer built fixed to one or or other supply system. The savings in not having a fully dual voltage fleet are marginal, thats not to say not worth doing, but probably marginal enough for the bean counters to consider it as a Capex saving. I personally doubt it is a whole life Opex fleet saving because I suspect they could get away with one less unit overall if they were all the same. All VVVF technology trains ... thats those with contemporary traction packs and AC motors ... are independent of traction supply system and can very easily be converted between AC or DC or both. Inside what happens is that either 750 V DC or 25 kV AC is converted to the HVDC link - not sure what it is in 378s but probably around 3000 V, converted again to VVVF (Variable Voltage Variable Frequency) AC to drive asynchronous motors, all done by electronics. Apart from the transformer, alterations are minimal and rapid, a pantograph is peanuts in todays scheme of things. The days of DC with resistor control and AC with tap changers, are long gone. The same traction /principles/ apply to S stock, the only thing here is that S stock bodies are not provisioned with pantograph wells nor underframes for transformers. But S stock could very easily have been built run off 25 kV if say there were some sort of transport coordination in this country and Chilterns lines were soon to be wired, and if someone fitted a couple of sets of points around West Hampstead, and so on. -- Nick Hi I know a little bit about Electrostars, maybe I can help. 25KV AC is transformed into 640 AC. This is then rectified into 750 DC by the line converter modukes before the motor converter modules convert it to 3 phase 750 volts AC for the motors. When running on DC, the 750 volts is simply changed into 750 AC three phase missing out the previous steps. The additional AC equipment is carried in the PTOS(L) vehicle - transformer and pantograph and there are additional line converter modules on motored coaches. |
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Post by Deleted on Apr 14, 2013 10:30:04 GMT
Modern trains are no longer built fixed to one or or other supply system. The savings in not having a fully dual voltage fleet are marginal, thats not to say not worth doing, but probably marginal enough for the bean counters to consider it as a Capex saving. I personally doubt it is a whole life Opex fleet saving because I suspect they could get away with one less unit overall if they were all the same. All VVVF technology trains ... thats those with contemporary traction packs and AC motors ... are independent of traction supply system and can very easily be converted between AC or DC or both. Inside what happens is that either 750 V DC or 25 kV AC is converted to the HVDC link - not sure what it is in 378s but probably around 3000 V, converted again to VVVF (Variable Voltage Variable Frequency) AC to drive asynchronous motors, all done by electronics. Apart from the transformer, alterations are minimal and rapid, a pantograph is peanuts in todays scheme of things. The days of DC with resistor control and AC with tap changers, are long gone. The same traction /principles/ apply to S stock, the only thing here is that S stock bodies are not provisioned with pantograph wells nor underframes for transformers. But S stock could very easily have been built run off 25 kV if say there were some sort of transport coordination in this country and Chilterns lines were soon to be wired, and if someone fitted a couple of sets of points around West Hampstead, and so on. -- Nick Hi I know a little bit about Electrostars, maybe I can help. 25KV AC is transformed into 640 AC. This is then rectified into 750 DC by the line converter modukes before the motor converter modules convert it to 3 phase 750 volts AC for the motors. When running on DC, the 750 volts is simply changed into 750 AC three phase missing out the previous steps. The additional AC equipment is carried in the PTOS(L) vehicle - transformer and pantograph and there are additional line converter modules on motored coaches. Which is a little different to other systems: where the DC voltage is more strictly controlled than that of the 3rd rail supply, requiring a higher DC voltage into the VVVF converters. |
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Post by d7666 on Apr 14, 2013 12:17:40 GMT
As low as 640 V DC ?
This is news to me.
I know there is no reason why it sould not be as low as that, but on most of the EMU, UK and elsewhere, where I have seen voltage values for these links they are at least 1500 V and often 3000 V or more. This applies even if the supply voltage is as low as 600 V, it still gets stepped up to 3000 V.
Having said that, I have not seen any DC link values for any of the Adtranz / Bombardier types built at Derby.
Does the 640 V you are cite just apply to 378s, or applies to all main line Electrostars (357/375/377/379 et al) ?
And how is this on S stock ?
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Nick
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Post by Deleted on Apr 14, 2013 15:02:44 GMT
Hi Nick
The 640V figure comes from the traction manual for 375s. Whether it is correct I am unsure? I know that 378s are quicker to accelerate under AC as indeed are most dual voltage units.
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Post by d7666 on Apr 14, 2013 18:56:24 GMT
Hi Nick The 640V figure comes from the traction manual for 375s. Whether it is correct I am unsure? I know that 378s are quicker to accelerate under AC as indeed are most dual voltage units. OK thanks for confirming. -- Nick |
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Post by Ben on Apr 23, 2013 0:48:05 GMT
On a slightly lateral note, presumably higher voltages (3000 vs 640 say) are prefered because of lower requirements for the conducter cross-section?
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Post by phillw48 on Apr 23, 2013 8:38:07 GMT
On a slightly lateral note, presumably higher voltages (3000 vs 640 say) are prefered because of lower requirements for the conducter cross-section? Higher voltages require less fixed equipment (sub stations etc.). High voltage is not suitable for third/fourth rail for various reasons such as safety. |
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