Track configuration differences

[adc82140]

I've noticed that there is a difference between the configuration of tracks on the Great Western mainline and the South Western Mainline (west of Earlsfield)- ie the layout on the GWML is Down fast-up fast-down slow-up slow, whereas on the SWML it's down slow-down fast-up fast-up slow.

I can see advantages for both- on the SWML trains can cross from the slow to fast lines and back without conflicting with trains going in the other direction, and smaller stations can be built without an island platform. On the GWML some engineering work can be carried out without having to close the entire line.

What is the historical reason for this difference?


TIA

 

[jopsuk]

I think it depends on the whim of the company that built the line, to a certain extent. The Great Eastern Mainline (out of Liverpool Street) is configured roughly similar to the GWML, as is the southern section of the West Anglia/Lee Valley lines.

the Great Northern (once it fully untangles itself from the arrangements for the suburban platfroms at Kings Cross, the Moorgate line and the Hertford Loop) has the fasts up the middle.

The line through Bromley South where four track (from Shortlands to Swanley) operates as up|down|up|down too, from what I remember of commuting there.

 

[Old Timer]

In a lot of ways it depends upon the Company, the reason for increasing the number of lines, and when it was done.

There was also the impact of road over rail bridges and how the arches were configured. It sometimes being cheaper to add an arch at each side for a single track rather than rebuild the bridge with a pair of arches.

For example Railway Companies that built additional running lines for freight. e g. LNWR / Midland in the middle part of the 19th Century, built them to one side so as to separate them completely from the passenger lines. The Goods lines were in various cases then Permissively signalled, whereas the Passenger lines were not.

Increasing passenger traffic led to the Goods lines being converted to Passenger use at a later stage.

Companies who increased the running lines for passenger traffic in the late 19th Century in many cases placed the Slow lines on the outside sometimes so as to avoid increasing the size of the station other times simply to prevent the need to cross over an already busy mainline when crossing from Fast to Slow and vice versa.

Running junctions were also cheaper to install and signal with minimal alterations to the interlocking on directionally paired lines compared to speed separated lines.

The GCR, which was built later had many of the stations placed on the outside so that express passenger trains could pass slower trains at stations on the fast lines. The slower trains could then cross back onto the fast and overtake freight trains running on the slows.

 

[bunnahabhain]

The GCR, which was built later had many of the stations placed on the outside so that express passenger trains could pass slower trains at stations on the fast lines. The slower trains could then cross back onto the fast and overtake freight trains running on the slows.

No it did not. The Great Central Main Line was a two track railway with island stations, exceptions to this rule being Rushcliffe Halt, Nottingham Arkwright Street and Carrington stations, the latter due to being built after the line, and the former two due to space constraints.

 

[Aictos]

The GCR, which was built later had many of the stations placed on the outside so that express passenger trains could pass slower trains at stations on the fast lines. The slower trains could then cross back onto the fast and overtake freight trains running on the slows.

That's not a bad idea, I suppose it was setup so the express trains could stop at some of the stations then cross back onto the fast?

 

[Old Timer]

No it did not. The Great Central Main Line was a two track railway with island stations, exceptions to this rule being Rushcliffe Halt, Nottingham Arkwright Street and Carrington stations, the latter due to being built after the line, and the former two due to space constraints.

West Ruislip, Beaconsfield, Gerrards Cross, High Wycombe, Princes Risborough are just a few that spring to mind :roll:

 

[mallard]

West Ruislip, Beaconsfield, Gerrards Cross, High Wycombe, Princes Risborough are just a few that spring to mind :roll:

Those are all on the GC/GW Joint, not the GCR proper.

 

[BuggieJack]

The Midland line, when it was widened to 4 tracks between New Mills South and Chinley North Junction was arranged Down Fast, Up Fast, Down Slow,Up Slow. This left Bugsworth station on the fast lines only, which was a bit of a nuisance as it was only served by local stopping trains. This operational difficulty ensured that few stopping trains actually stopped at Bugsworth.

 

[Spartacus]

One unusual bit of line I know about is from Wakefield Kirkgate to Horbury Jn where the fasts are on the outside and the slows on the inside. I think this was due to Healey Mills yard being built in the centre of the running lines, but I'm unsure how far past there this configuration continued.

 

[Old Timer]

Healey Mills yard.

A place of mystery and romance to us southern lads when it really was a marshalling yard 40 years ago.

Somewhere as exotic and exciting to get to (and about as hard to as well !) as New York.

I have memories from long, long ago of visiting Healy Mills, just a friend and I, followed by Frodingham, a run to Cleethorpes, and then travelling back from Cleethorpes to Grimsby (where she got off :cry::cry::cry::cry beside a truly beautiful blonde angel.

A day of great joy followed by immense sadness as the MetCam sped away from the Grimsby skyline leaving my heart behind, never again to be found :cry::cry:

 

[DaveNewcastle]

. . . . I have memories from long, long ago of visiting Healy Mills, . . . . . . A day of great joy followed by immense sadness as the MetCam sped away from the Grimsby skyline leaving my heart behind, never again to be found :cry::cry:

Er, wasn't that Hayley Mills?
(dives for cover)

 

[generalvegitable]

One unusual bit of line I know about is from Wakefield Kirkgate to Horbury Jn where the fasts are on the outside and the slows on the inside.

There is a similar situation on the Euston station approaches, the fast lines are on the outside, and the slow and new lines are on the inside

 

[Old Timer]

Changed now Chap, its lines 1 to 6. Bloody silly way of naming lines !

What was wrong with down and up Fast / Slow / DC ????

Probably too difficult for the burger bar managers and newbies into the Industry

Er, wasn't that Hayley Mills?
(dives for cover)

That was our nick name for Healy Mills, based on the rounded Northern vowels found thereabouts.

Little did I know in those days I would end up working there !

 

[DaveNewcastle]

Very good!