Deleted
Deleted Member
Posts: 0
|
Post by Deleted on May 20, 2014 20:15:16 GMT
Hello  As I was making my way in to the city this morning I noticed that my train was much squeakier than usual when pulling away, but also under braking too and there was generally a lot of squealing from the rails and/or wheels. Mine wasn't the only one, either, I noticed one on the eastbound at Leyton making just as much noise. My first question, simply for my own interest and edification is - is this, in general, something that could be caused by low adhesion? Was I right to suspect that that could be related, or do I simply not understand the term properly? That's really my main reason for asking, I'm just curious about the terminology and causes and I'm sure a little squeaking is not a very big deal, it must happen all the time, I just noticed it was quite prominent this morning. But I'm asking here in case there was something different about the Central line this morning, does anyone know if those metals were especially greasy today or something like that, or is this just another day in the life of London Underground? |
|
|
|
Post by Dstock7080 on May 20, 2014 21:26:18 GMT
A lot of milling/grinding has been taking place on the Central (and other west London lines) recently, taken from a Staff newsletter:
A new track record for Central line.
Four rail profiling machines help deliver 35.5km of improvements for Track Delivery Unit (TDU),
Over the bank holiday weekend, while many people would have been relaxing at home enjoying the sunshine, a massive operation was underway on the west end of the Central line by the Track Delivery Unit (TDU) to improve the track between West Ruislip and White City.
Close collaboration between the LU planners, project team and a number of external suppliers from across Europe saw the largest single weekend of rail grinding and milling ever delivered anywhere on the Tube network with a total of 35.5km of rail re-profiling successfully delivered, some 1.5 kilometres above the original project scope.
Four rail re-profiling machines, some of which have never before been used on the LU network, were supplied by Schweerbau GMBh, Speno International & Strabag for this project – making the project a truly international effort!
Additional work carried out over the 72 hours included drainage works at North Acton, points and crossing grinding works at Ealing Broadway, North Acton, Northolt and West Ruislip, along with improvements to the track within Ruislip depot.
TDU Senior Project Delivery Manager Derek Greer was full of praise for everyone involved in the rail defect reduction project: “The amazing amount of work carried out demonstrates what can be achieved when a number of different departments and disciplines from across the business work closely with our suppliers to achieve our shared goal of delivering an outstanding Tube for London. Well done to everyone involved!”
Key project milestones and achievements
· 35.5km rail re-profiling (five per cent of Reliability & Safety programme scope)
· 12 sets of points ground
· New drainage installed at North Acton
· Re-timbering through nine sets of points within Ruislip depot
· Preparing and replacing 100 metres of conductor rails from upside down 47 kilograms bull head rail to conventional 74 kilograms conductor rail"
|
|
|
|
Post by domh245 on May 20, 2014 21:32:20 GMT
But did this grinding also happen on the East end of the Central, or have they been grinding during engineering hours?
|
|
|
|
Post by superteacher on May 20, 2014 22:07:07 GMT
Is the purpose of rail grinding purely to improve ride quality, which then reduces wear and tear to the trains and tracks. I don't suppose it will reduce vibration, and therefore allow the 92 stock to return to 100kph running?
|
|
hobbayne
RIP John Lennon and George Harrison
Posts: 516
|
Post by hobbayne on May 21, 2014 19:03:49 GMT
There has been new rails laid in the Leyton area during engineering hours recently.
The 92 stock is capped at 85kph. 100 kph is still available in coded manual but is not allowed.
|
|
|
|
Post by superteacher on May 21, 2014 19:46:40 GMT
Yes it was capped at 85 kph following the Chancery Lane derailment. My question was regarding if there is a possibility of 100 kph running being reinstated if the track quality improves?
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on May 21, 2014 19:47:26 GMT
Thanks for the information I guess it was nothing really of importance or connected to anything, since I noticed a lot of squeaking, really, from Woodford all the way to Liverpool Street. I dunno, maybe it was even specific to that train. But I'm sure new rails in the Leyton area would have contributed. I was coming in on the west and I noticed a lot of squeaking from the one pulling out of the eastbound platform. It was probably nothing, but I'm glad I asked, I got a lot of unexpected, interesting information. So I'm right, at least, in thinking that "low adhesion" - whether or not it was the cause here - could cause some squeaking and squealing to be heard, especially when pulling away? |
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on May 21, 2014 19:53:17 GMT
Yes it was capped at 85 kph following the Chancery Lane derailment. My question was regarding if there is a possibility of 100 kph running being reinstated if the track quality improves? I'm by no means in the know, but I thought it had long been ruled pretty unlikely given the info in this thread including your own observation about how much it vibrated and I think, even with new track in place, it's likely that it'd still give pretty poor ride quality for very little return. The observation that it's very difficult even to accelerate up to 100 kph is also telling , don't you think? That said you probably don't need me to tell you that and I too would be very interested if somebody came along with the information that that was being planned, but I wouldn't get your hopes up |
|
|
|
Post by superteacher on May 21, 2014 20:21:47 GMT
Yes it was capped at 85 kph following the Chancery Lane derailment. My question was regarding if there is a possibility of 100 kph running being reinstated if the track quality improves? I'm by no means in the know, but I thought it had long been ruled pretty unlikely given the info in this thread including your own observation about how much it vibrated and I think, even with new track in place, it's likely that it'd still give pretty poor ride quality for very little return. The observation that it's very difficult even to accelerate up to 100 kph is also telling , don't you think? That said you probably don't need me to tell you that and I too would be very interested if somebody came along with the information that that was being planned, but I wouldn't get your hopes up 100 kph was achieved in quite a few places - the 92 stock have some serious acceleration! Most of the Ruislip and Epping branches had 100kph target speeds (and actually still do, although as has been pointed out, driving in coded manual at that speed is not permitted). I have heard it discussed that the speed in some of the tunnel sections would be slightly higher but for the poor track quality. Mile End to Stratford is a case in point. |
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on May 21, 2014 20:31:22 GMT
I'm by no means in the know, but I thought it had long been ruled pretty unlikely given the info in this thread including your own observation about how much it vibrated and I think, even with new track in place, it's likely that it'd still give pretty poor ride quality for very little return. The observation that it's very difficult even to accelerate up to 100 kph is also telling , don't you think? That said you probably don't need me to tell you that and I too would be very interested if somebody came along with the information that that was being planned, but I wouldn't get your hopes up 100 kph was achieved in quite a few places - the 92 stock have some serious acceleration! Most of the Ruislip and Epping branches had 100kph target speeds (and actually still do, although as has been pointed out, driving in coded manual at that speed is not permitted). I have heard it discussed that the speed in some of the tunnel sections would be slightly higher but for the poor track quality. Mile End to Stratford is a case in point. Ah now MIE - STR is a very good example. *Shrug*, I don't presume to know, but I would be surprised. Don't you think you'd just be left with a queue to get into Epping? Mind you, as you say, it was managed before, but was the frequency as intensive then? Well, perhaps it would shave a minute or so off the journey time to Epping, but I'd imagine that would bring little real major line-wide benefit, as I can't see the ageing 92s, or the packed pipe, or bottlenecks like Leytonstone handling more trains on the timetable. Still, I should probably stop speculating and wait for someone with the knowledge to tell us whether or not it's in the works, but I'll pin my colours firmly to the 'sceptical' pole  Not to mention the cynical one  |
|
|
|
Post by superteacher on May 21, 2014 20:44:30 GMT
Epping is a two platform terminus so as long as there is a platform to run into, the extra speed wouldn't cause a queue. Remember that trains would be going 100 kph in both directions, so it would balance itself out. But it could all be conjecture anyway!
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on May 21, 2014 20:51:21 GMT
Well I was foreseeing that with trains steaming up to Epping at 100 kph there might very well not be a platform going spare; but you're right, conjecture, I'm sure they'll only bother with the hassle if there's a good reason for it. LUL does not like to bother with hassle, but then it doesn't always get it right when judging whether or not its reasons are good, or when judging the extent of the hassle it's signing up for |
|
|
|
Post by domh245 on May 21, 2014 20:58:35 GMT
I seem to remember hearing that the 92TS have a very intensive maintenance regime, with almost no spare trains, so it is doubtful that 100kph could be run now without more trains. Perhaps the 92TS from the drain could be cascaded to the Central (along with the necessary upgrades) to allow a few extra trains, but all of the upgrades would be fairly costly, for not a huge return, so I doubt it'll happen at the moment. Whilst it may happen with the arrival of the NtFL but then it would be a very limited timescale
|
|
|
|
Post by superteacher on May 21, 2014 21:18:33 GMT
Yes the Central line timetable is so intensive nowadays, so it's probably a big job trying to keep enough trains serviceable. Gone are the days when nearly half the trains did nothing outside the peaks, making it easy to service the trains and reduce wear and tear. The A stock had quite an easy life in their 50 years of service. If a modern train lasts that long, it would be miracle considering the huge increase in off peak services.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on May 21, 2014 21:38:57 GMT
Just imagine an in service Marble Arch to Liverpool Street Sunday shuttle now! |
|
|
|
Post by superteacher on May 21, 2014 21:44:40 GMT
Just imagine an in service Marble Arch to Liverpool Street Sunday shuttle now! Sunday service is 21 tph through the Central area now, which would have been unthinkable a few years ago! Was there ever a Sunday shuttle? I think the Marble Arch to Liverpool Street shuttle only ever ran in the Monday to Friday midday off peak. |
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on May 21, 2014 21:49:59 GMT
Ahhhh I thought it was only ever on Sundays for the shoppers, but I could easily have that back to front |
|
hobbayne
RIP John Lennon and George Harrison
Posts: 516
|
Post by hobbayne on May 22, 2014 9:55:33 GMT
Just imagine an in service Marble Arch to Liverpool Street Sunday shuttle now! Sunday service is 21 tph through the Central area now, which would have been unthinkable a few years ago! Was there ever a Sunday shuttle? I think the Marble Arch to Liverpool Street shuttle only ever ran in the Monday to Friday midday off peak. Thats right. The MAA - LIS sevice ran M-F between the peaks. It was the most mind numbingly boring thing I ever done (Apart from the HOL-ALD shittle. IIRC it was 12 mins running time and 15 mins in the turnback sidings. Two or three times. When I came back to the Central after years in exile on the Picc, I was glad to hear they had been withdrawn as the Oxford St traders association had withdrawn their funding. |
|
North End
Beneath Newington Causeway
Posts: 1,769
|
Post by North End on May 22, 2014 14:21:23 GMT
100 kph was achieved in quite a few places - the 92 stock have some serious acceleration! Most of the Ruislip and Epping branches had 100kph target speeds (and actually still do, although as has been pointed out, driving in coded manual at that speed is not permitted). I have heard it discussed that the speed in some of the tunnel sections would be slightly higher but for the poor track quality. Mile End to Stratford is a case in point. Ah now MIE - STR is a very good example. *Shrug*, I don't presume to know, but I would be surprised. Don't you think you'd just be left with a queue to get into Epping? Mind you, as you say, it was managed before, but was the frequency as intensive then? Well, perhaps it would shave a minute or so off the journey time to Epping, but I'd imagine that would bring little real major line-wide benefit, as I can't see the ageing 92s, or the packed pipe, or bottlenecks like Leytonstone handling more trains on the timetable. Still, I should probably stop speculating and wait for someone with the knowledge to tell us whether or not it's in the works, but I'll pin my colours firmly to the 'sceptical' pole Not to mention the cynical one A few points taking up various items in this thread. Firstly, 100 kph was definitely regularly achieved pre-Chancery Lane, in places where the track was in a far worse condition than today (anyone remember Northolt to South Ruislip?!). Certainly on many of the longer open-section runs 100 kph could be and was easily achieved. It is still more than possible for the trains to reach this speed, as Coded Manual operation still gives a 100 kph target speed, however there is a standing instruction in place that trains should not exceed 85 kph. The 85 kph restriction was imposed following the Chancery Lane derailment in order to reduce vibrations from the traction motors, I don't think it was anything to do with the track condition. I have seen documentation suggesting that 100 kph operation was to be restored from the latest timetable, however this doesn't appear to have happened. There was also a plan to increase tunnel brake rates to their originally designed level, which I don't think had ever previously been achieved. This change is definitely still on the agenda, not sure if it's actually happened yet or not. Given the line continuously struggles to provide enough trains to run the service, any further increase in service I would imagine would *have* to rely on increased performance, therefore I would speculate that reversion to 100 kph operation is definitely a possibility for the future. I don't think the 92 stock target speed exceeds 65 kph in any tunnel sections (I'd be interested to know if anyone can say otherwise on this). By network standards this is quite low, as the Jubilee and Victoria Lines regularly reach 50 mph or more, and even the Northern Line reaches 40 mph in a small number of locations. Interestingly, the 1971 Central Line supplement gives a 45 mph maximum permitted speed east of Liverpool Street. |
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on May 22, 2014 14:30:01 GMT
Thank you for that North End, much appreciated. I stand corrected This thread gives some useful information. Auxsetreq agrees with you that the maximum maximum safe speed, as it were (or, probably more specifically, the maximum target speed, but I couldn't resist the wordplay ), in the tunnels is 65 kph, although Tom quotes Code 8 - 75 kph, which is of course, as he says, a tad over 45 mph. |
|
As I was making my way in to the city this morning I noticed that my train was much squeakier than usual when pulling away, but also under braking too and there was generally a lot of squealing from the rails and/or wheels. Mine wasn't the only one, either, I noticed one on the eastbound at Leyton making just as much noise.
Not to mention the cynical one 
