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Journey by Journey => Wales local journeys => Topic started by: grahame on January 24, 2019, 13:36:17



Title: Valley lines - a journey report from recent days
Post by: grahame on January 24, 2019, 13:36:17
A review of the Welsh Valley lines as they are and operate at the moment by Gareth David at railwayworld.net (https://railwayworld.net/2019/01/24/how-green-was-my-valley/)

Quote
Having previously travelled the Aberdare and Ebbw Vale lines, my challenge, using more bargain-priced GWR January promotional fares and an Explore Cardiff & Valleys day ranger ticket, was to complete my Welsh rail mileage by travelling the three principal Valleys Lines – to Treherbert, Merthyr Tydfil and Rhymney.

...

Worth a read


Title: Re: Valley lines - a journey report from recent days
Post by: eightf48544 on January 24, 2019, 15:23:37
Very interesting. Wonder what he would have said if he'd done it summer with the lineside trees in leave and the views obscured?


Title: Re: Valley lines - a journey report from recent days
Post by: Worcester_Passenger on January 24, 2019, 18:43:23
And, in my exerience, a staggering quantity of Japanese knotweed.

Meanwhile, a technical question for the signalling experts. The article describes the Treherbert branch as being operated with the drivers extracting the single-line tokens at Porth. I go to Porth from time to time, and there's two little huts on the platforms which house the token machines. Does this mean that over a day all the tokens from the northbound platform hut end up in the southbound one? And who moves them all back again (and when)?


Title: Re: Valley lines - a journey report from recent days
Post by: MVR S&T on January 24, 2019, 19:15:15
With a magazine of tokens such as:

https://photos.signalling.org/picture?/19100/category/1904-ystrad_rhondda



Title: Re: Valley lines - a journey report from recent days
Post by: martyjon on January 24, 2019, 20:24:46
Having examined a token instrument in the past I would assume a little man wearing a HV uniform emblazoned with the words NETWORK RAIL on the rear would come along with his key, open up the token instrument, count out a number of the tokens, record the number removed, lock up the token instrument and then carry out the reverse of the preceding to replace the tokens in the other instrument making sure the number replaced is equal to the number removed. Have to check next time I'm in a signal box using this method of working. That will be the next time I visit Didcot Railway Centre.


Title: Re: Valley lines - a journey report from recent days
Post by: grahame on January 24, 2019, 20:51:41
With a magazine of tokens such as:

https://photos.signalling.org/picture?/19100/category/1904-ystrad_rhondda


Looks like (with the section closed) the magazine could be transferred from one instrument to the other, with mechanical locking to ensure tokens couldn't be taken out of either instrument or magazine when it was detached.  Then a simple swap of the magazines without any need to count / sign for, and no potential question of it happening anything but the right way.

Good question ... I learn something every day.


Title: Re: Valley lines - a journey report from recent days
Post by: MVR S&T on January 24, 2019, 21:06:43
The same system is in use between Maiden Newton and Yeovil Pen Mill, with two cabins at Maiden Newton. as well as a fixed magazine a single portable one can be provided, for the transport of token between cabins or even between Maiden Neweton and YeovilPen Mill sgnal box or vice versa. As long as only one can ever be taken by a driver/signalman, to provide security of the single line. And the sytem can interface with a panel, such as at Dorchester so could be linked to a ASC or IECC at Basingstoke say.


Title: Re: Valley lines - a journey report from recent days
Post by: eightonedee on January 24, 2019, 22:20:01
(Is this thread an attempt to lure S&T Engineer back into print - hope it works!)


Title: Re: Valley lines - a journey report from recent days
Post by: grahame on January 24, 2019, 23:16:24
(Is this thread an attempt to lure S&T Engineer back into print - hope it works!)

I started the thread. No such intent, and how could there have been when I was starting a thread pointing you to a travelogue which only had little bit of signalling in it.  Having said which, I would clearly welcome back any poster who has lapsed their posting through their choice who would like to contribute again.


Title: Re: Valley lines - a journey report from recent days
Post by: Worcester_Passenger on January 25, 2019, 17:53:26
Thanks for those.

I think there's about 30 trains per day in each direction - which would make the moving of the tokens a daily task.


Title: Re: Valley lines - a journey report from recent days
Post by: grahame on January 25, 2019, 20:31:35
Thanks for those.

I think there's about 30 trains per day in each direction - which would make the moving of the tokens a daily task.

I'm sure it is ... probably cheaper that signalling both platforms bidirectional and crossing alternately left to right and right to left. And imagine the confusion that would cause passengers.

More sensibly with bidirectional loops, you could take the train to Cardiff from the main platform - with all the facilities - in the morning, then in the afternoon have the trains from Cardiff drop off at that main platform.  In fact I thing there are places where trains only use the loop when crossing, with that use being by the more secondary train.  Can anyone confirm that?


Title: Re: Valley lines - a journey report from recent days
Post by: SandTEngineer on January 25, 2019, 21:27:44
Its all explained here: http://www.railsigns.uk/info/nstr1/nstr1.html


Title: Re: Valley lines - a journey report from recent days
Post by: Worcester_Passenger on January 25, 2019, 22:04:20
Its all explained here: http://www.railsigns.uk/info/nstr1/nstr1.html
Thanks for that.


Title: Re: Valley lines - a journey report from recent days
Post by: WSW Frome on January 26, 2019, 16:19:11
An similar example of Grahame's query is Dorchester South, where the main (northside) platform is prioritised for bi-directional travel except when a crossing movement is required. Gillingham (Dorset) the same.


Title: Re: Valley lines - a journey report from recent days
Post by: rogerw on January 26, 2019, 17:31:52
Honiton is also the same


Title: Re: Valley lines - a journey report from recent days
Post by: SandTEngineer on January 26, 2019, 18:15:07
The most economical way to do it is to do a 'Penryn' (as in Cornwall).  No footbridge and only one set of passenger facilities required: https://thestationmaster.files.wordpress.com/2012/04/penryn-station.jpeg and https://s0.geograph.org.uk/geophotos/02/01/49/2014968_4fda9823.jpg

I did once look at this for Grahame for a potential solution for a crossing loop at Melksham :D


Title: Re: Valley lines - a journey report from recent days
Post by: brooklea on January 26, 2019, 18:21:14
In fact I thing there are places where trains only use the loop when crossing, with that use being by the more secondary train.  Can anyone confirm that?
Weston-super-Mare being another


Title: Re: Valley lines - a journey report from recent days
Post by: eightf48544 on January 27, 2019, 16:14:32
I first came across the single platform passing loops on the Bostock Bad Dobran line in the early 2000s> However as I understand it  the difference is that in Germany the trains don't pass before reaching the platform. they stop nose to nose  with the point for the loop in the gap. Hopefully the train for which the loop is a facing point starts first


Title: Re: Valley lines - a journey report from recent days
Post by: SandTEngineer on January 27, 2019, 22:29:56
I first came across the single platform passing loops on the Bostock Bad Dobran line in the early 2000s> However as I understand it  the difference is that in Germany the trains don't pass before reaching the platform. they stop nose to nose  with the point for the loop in the gap. Hopefully the train for which the loop is a facing point starts first
Yes, but due to the need to have sufficiently long signal overlaps, that makes the station platforms veryyyyyyyyy longgggggggg :P


Title: Re: Valley lines - a journey report from recent days
Post by: grahame on January 28, 2019, 07:45:50
I first came across the single platform passing loops on the Bostock Bad Dobran line in the early 2000s> However as I understand it  the difference is that in Germany the trains don't pass before reaching the platform. they stop nose to nose  with the point for the loop in the gap. Hopefully the train for which the loop is a facing point starts first
Yes, but due to the need to have sufficiently long signal overlaps, that makes the station platforms veryyyyyyyyy longgggggggg :P

The "Penryn Solution" seems to me to have the best potential where the trackbed for the rest of the line is single track, and where a clockface service of relatively short workings that are broadly independent of other services are to be run, all calling at the passing place station.   As someone else raised Melksham, yes, it's an option though not ideal;  the alternative(s) is / are dynamic loops on the the long stretches from just north of Melksham Statioon nearly to Thingley, and / or from just south of Melksham Station to just north of the Avon Bridge at Staverton. Sure, other options start off as simple as an intermeiate signal (which as a limited intervention would only give a limited return) through to full redoubing which surprsingly would not solve issues of faster trains needing  to overtake slower ones somewhere between Westbury and Swindon.


Title: Re: Valley lines - a journey report from recent days
Post by: Gordon the Blue Engine on January 28, 2019, 09:06:26
I first came across the single platform passing loops on the Bostock Bad Dobran line in the early 2000s> However as I understand it  the difference is that in Germany the trains don't pass before reaching the platform. they stop nose to nose  with the point for the loop in the gap. Hopefully the train for which the loop is a facing point starts first
Yes, but due to the need to have sufficiently long signal overlaps, that makes the station platforms veryyyyyyyyy longgggggggg :P

Maybe they could signal it like P12-15 at Reading: the approach control and mid platform Stop boards apparently help S&T Engineers get round the need for proper overlaps.   


Title: Re: Valley lines - a journey report from recent days
Post by: eightf48544 on January 28, 2019, 10:26:36
Maybe I should have  the Bad Dobran line doesn't have any freight traffic it's all 2 possibly 4 (2*2 ) car DMUs.

Yes the platform at Bad Doran is pretty long. So probably only applicable on lines with only short passenger trains.

The other common station layout on double track lines is 3 platforms mainlines and a bi directional loop for stopping trains, although I have ben round the loop on an IC  at an intermediate station between Hanover and Magdeburgh to overtake a freight train. 

Most through platforms at Reading do have intermediated stop boards.


Title: Re: Valley lines - a journey report from recent days
Post by: stuving on January 28, 2019, 10:42:33
Most through platforms at Reading do have intermediated stop boards.

Actually, all of them. The Western Sectional Appendix says:

Quote
READING
A ‘Rear Clear Marker’ board is a circular board with white background, a black triangle and numerals in black font.
These boards are located on platforms 7 to 15, they are positioned approximately halfway along the platform and are applicable to DMUs and EMUs with a consist of 2 to 5 vehicles. The boards apply to trains travelling in either Up and Down direction, and are reversing in the station.
Drivers, of DMU’s or EMU’s, with a consist of 2 to 5 vehicles, must stop the train 5 metres from the board if the service is to reverse in the platform and the next journey will be in the opposite direction to the arrival.
Drivers of formations that consist of more than 5 vehicles must go passed the ‘Rear Clear Marker’ board and stop the train at the normal stopping location for the formation they are driving.
Dated: 25/03/17

But that has nothing to do with whether permissive working is allowed - it only simplifies a train stopping at the first half of a platform. Permissive working is allowed in all platforms (1-15) other than P12P11 in the Down direction, with (as far as I can see) the same rules.


Title: Re: Valley lines - a journey report from recent days
Post by: IndustryInsider on January 28, 2019, 11:18:38
But that has nothing to do with whether permissive working is allowed - it only simplifies a train stopping at the first half of a platform. Permissive working is allowed in all platforms (1-15) other than P12 in the Down direction, with (as far as I can see) the same rules.

P12 is OK for permissive working both directions, it's P11 in the down direction that isn't.


Title: Re: Valley lines - a journey report from recent days
Post by: grahame on January 28, 2019, 11:22:31
The other common station layout on double track lines is 3 platforms mainlines and a bi directional loop for stopping trains, although I have ben round the loop on an IC  at an intermediate station between Hanover and Magdeburgh to overtake a freight train. 

Ironically that too could have its uses in Wiltshire - a bidirectional loop at Chippenham alongside the spare platform face.   Many and varied uses ...


Title: Re: Valley lines - a journey report from recent days
Post by: stuving on January 28, 2019, 11:25:46
But that has nothing to do with whether permissive working is allowed - it only simplifies a train stopping at the first half of a platform. Permissive working is allowed in all platforms (1-15) other than P12 in the Down direction, with (as far as I can see) the same rules.

P12 is OK for permissive working both directions, it's P11 in the down direction that isn't.

You're right, of course - my mis-copying.



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