Ground Frames

RichmondCommu · 11 Oct 2013

G'day all,

I'm interested to know what circumstances need to exist for Ground Frames to have been installed as opposed to direct control by a signal box. Are Ground Frames ever connected to the mainline and if so how are the points protected? Were they always exposed to the elements? Also how were they locked and who operated them? I'm guessing that it would always have been the driver and his guard?

Finally I would be interested to learn about Ground Frames that still exist on Network Rail. The only one I was aware of was on the Denby branch in Derbyshire but the track has since been lifted.

Your contributions would be very welcome.

Kind regards,

Richmond Commuter.

RailUK Forums

Tomnick · 11 Oct 2013

Typically you'd find a ground frame to operate relatively infrequently used siding connections or crossovers that are distant from the controlling signal box (in mechanical areas) or where there was no justification for including the connection in a power signalling scheme. There are examples of the former on our patch at Melton Jcn (giving access to Old Dalby) and Ketton (for the cement works), both within the station limits of their respective signal boxes, and of the latter at Belper (engineers' sidings on the up side). Usually an electrical release from the controlling box. You'll sometimes find them partway along single lines too, released by the staff or token and controlling intermediate sidings or run-round loops (sometimes with the ability to shut a train inside and resume operations on the single line), connections to branches off the branch (Looe!) or reversals within the single line section (Bere Alston).

RichmondCommu · 11 Oct 2013

Tomnick said:
Typically you'd find a ground frame to operate relatively infrequently used siding connections or crossovers that are distant from the controlling signal box (in mechanical areas) or where there was no justification for including the connection in a power signalling scheme. There are examples of the former on our patch at Melton Jcn (giving access to Old Dalby) and Ketton (for the cement works), both within the station limits of their respective signal boxes, and of the latter at Belper (engineers' sidings on the up side). Usually an electrical release from the controlling box. You'll sometimes find them partway along single lines too, released by the staff or token and controlling intermediate sidings or run-round loops (sometimes with the ability to shut a train inside and resume operations on the single line), connections to branches off the branch (Looe!) or reversals within the single line section (Bere Alston).

Many thanks for your very interesting post. I'm assuming that in the examples you have cited in the East Midlands the driver has to contact the signal box in order to have the Ground Frame released? I'm assuming that once a train has passed over the points the Ground Frame is locked. I apologise for what must seem to be stupid questions but signaling fascinates me!

alex17595 · 11 Oct 2013

There is one to get onto the heysham port branch (1tpd). The train stops just before entering the branch and just after leaving to set it. I think someone comes from the station to do it.

High Dyke · 11 Oct 2013

RichmondCommu said:
Many thanks for your very interesting post. I'm assuming that in the examples you have cited in the East Midlands the driver has to contact the signal box in order to have the Ground Frame released? I'm assuming that once a train has passed over the points the Ground Frame is locked. I apologise for what must seem to be stupid questions but signaling fascinates me!

Communication can be achieved in a couple of ways...either by phone or bell signals, with a small plunger provided at the Ground Frame (GF). The ones i have been familiar with require communicating with the controlling signalbox who operates a switch or lever to give an electrical release to the GF.

The interlocking of the GF means that when in operation the normal main line signalling remains at Danger until the GF has been restored to 'Normal'. At some locations where it may be needed to lock an engine into the siding a token release instrument may be provided (depending on the type of signalling used on that line). More often than not though the engine shunting a siding controlled by a GF may only be there for that specific purpose and then continue on its journey.

Other examples of GF's are at termini stations to provide a shunt release for an arriving loco. Great Yarmouth is one that springs to mind as does Norwich and Skegness though i don't think any of them see any regular use these days.

In some locations the traditional Ground Frame may be replaced by a small switch panel.

Tomnick · 11 Oct 2013

High Dyke's just about answered everything, I think - certainly every ground frame requiring a release from the box has relied on telephone communication. Quite often, nowadays, a Shunter is provided to operate the ground frame and see the train inside: that's certainly the case at Ketton, where there's sometimes a bit of proper shunting to be done (at the main line end) anyway. Once you've given a ground frame release, they're free to shunt back and forth - they'll then advise you when they're finished. Rothley Brook GF on the GCR is another good example, controlling access to sidings on both sides of the single line.

Perhaps the best example of ground frames on a single line, with the ability to shut inside, is the Glaisdale - Whitby section, with ground sections at Grosmont and Bog Hall (both with instruments to allow the token to be restored and another released somewhere else, and another to allow a two-car DMU to be shut 'inside' at the buffer stops at Whitby). Both ground frames will be released by the token to prove that there's nothing moving anywhere in the section.

swt_passenger · 11 Oct 2013

There's a couple of examples of ground frame controlled crossovers on the Fareham to Southampton line, which come into use fairly regularly ( a couple of times a year?) for routine engineering work closures, they allow the route to be operated with reversals and/or shunts at Woolston or Netley. The GFs are positioned just east of Woolston, and just west of Netley, and what usually happens is that NR have a couple of chaps there for the day operating out of a van in the carpark...

duffield · 11 Oct 2013

Last night's episode of "The Railway:First Great Western" on CH5 actually showed one of the train crew operating the ground frame at Bere Alston.

Incidentally I'd recommend this programme (although I suppose it's nearly finished now I assume it will get repeated or be available on demand). It's got a surprising amount of technical detail for a 'mainstream' program, and lots of HST related stuff, plus some good scenery etc.

Edit: Just checked, whole series is available on CH5 website including last night if you want to see the ground frame being operated.

matchmaker · 11 Oct 2013

They are not uncommon. There is one at Dalnacardoch (or is it Dalanraoch?) on the Highland main line which controls an emergency crossover in the middle of the long double track section from Blair Atholl to Dalwhinnie. It is released from one (or is it both?) of the boxes.

Captain Chaos · 11 Oct 2013

I use the Groundframe at Bourne End for the Marlow branch. Used to be 2 locking levers and a points lever but is controlled by a switch panel now. Not sure how long it will last though. Slough box is supposed to shut and move to TVSC end of the year so no idea what they plan on doing with it!

Pacerpilot · 11 Oct 2013

Funnily enough, I worked through a ground frame two hours ago. This one permits access to the aggregate sidings at Neath Abbey wharf. The frame is unlocked with an Annetts Key (released upon a phone call to Port Talbot panel) and is operated by a shunter.

http://www.flickr.com/photos/88406088@N02/10206875833/sizes/l/in/photostream/

TheEdge · 11 Oct 2013

There is another one at Great Yarmouth. Released by the box it forms the run round loop in P2 and 3.

30907 · 11 Oct 2013

To answer one of the OP's points - Ground Frames were/are mostly exposed to the elements, but there were examples in a ground-level wooden signalbox-like structure, and there are or were some examples that started life as signalboxes but have been downgraded.

This site might interest you (or occupy you for hours....)
http://www.signalbox.org/index.php

Nippy · 11 Oct 2013

Captain Chaos said:
I use the Groundframe at Bourne End for the Marlow branch. Used to be 2 locking levers and a points lever but is controlled by a switch panel now. Not sure how long it will last though. Slough box is supposed to shut and move to TVSC end of the year so no idea what they plan on doing with it!

Slough not coming into TVSC at the end of the year now. The bit round West Drayton is but the rest will follow later. As far as I know when the rest comes in, the Bourne End branch remains the same for a while but will eventually be axle counters and signals.

Crossover · 11 Oct 2013

Are there any ground frames on the mainlines? I had a feeling there were some manual emergency crossovers on the likes of the WCML (indeed, wasn't there one at Lambrigg that caused the accident a few years ago?)

alex17595 said:
There is one to get onto the heysham port branch (1tpd). The train stops just before entering the branch and just after leaving to set it. I think someone comes from the station to do it.

The points are driver operated (the guard does the door)

The first time I did the branch, the poor driver had to jump down in monsoon like conditions, only for it to be pretty much dry again by the time we arrived at Heysham Port!

Signal Head · 11 Oct 2013

Crossover said:
Are there any ground frames on the mainlines? I had a feeling there were some manual emergency crossovers on the likes of the WCML (indeed, wasn't there one at Lambrigg that caused the accident a few years ago?)

When the northern LMR section of the WCML was resignalled in the 1970s, several GF-controlled emergency crossovers were put in. Some of these wre in pairs (ie facing and trailing), to assist with single working for engineering work or other blockages.

Over the years quite a few were converted to power operation, still locally controlled from a switch panel, released from the PSB in a similar way as the original GF.

Others were converted to fully worked points (ie controlled from the interlocking by route-setting) as part of minor signalling alterations, eg south end of Tebay loop when that was made bi-directional in the 1980s, the former GF connection is now the route for Up trains to get back onto the Up Main when exiting the loop, which is on the Down side.

In recent years there has been a programme of recovering the remaining ones as they are considered uneccessary.

edwin_m · 11 Oct 2013

There are crossovers both ways next to each other at Accrington. Last time I looked one of them was controlled from Preston and the other one was on a ground frame (or rather a ground panel).

The Planner · 11 Oct 2013

Signal Head said:
In recent years there has been a programme of recovering the remaining ones as they are considered uneccessary.

That is coming back to bite as single line sections are now too long to be useful. North of Preston there is talk of upgrading Garstang and the hassle that was had in getting rid of Harrison's was massive. Penrith is being upgraded and a plan to rip out Clifton and Lowther is likely to be dropped.

If people want to look for them download the appendices and look for the symbols that look like toast racks.

Joseph_Locke · 12 Oct 2013

The Planner said:
That is coming back to bite as single line sections are now too long to be useful.

Planner, I once heard a comment that a facing / trailing crossover pair every ten miles or so was (then) a good idea? Some of the WCML EGF recoveries were prompted as much by the strange places they were located (in terms of curvature, access, etc.) as much as the longer-term cost point of view.

Any new provision would be box-worked now anyway; I think all the WCML former GF and EGF (except Quintinhill) are now on the box?

Ships · 13 Oct 2013

Joseph_Locke said:
Planner, I once heard a comment that a facing / trailing crossover pair every ten miles or so was (then) a good idea? Some of the WCML EGF recoveries were prompted as much by the strange places they were located (in terms of curvature, access, etc.) as much as the longer-term cost point of view.

Any new provision would be box-worked now anyway; I think all the WCML former GF and EGF (except Quintinhill) are now on the box?

I can tell you this is a massive pain in the backside when we are doing renewals on both roads up that way and the engineering trains and tampers need to go miles to cross over. Even the planners weren't 100% sure which cross overs where there and which had been abandoned.

The Planner · 13 Oct 2013

Joseph_Locke said:
Planner, I once heard a comment that a facing / trailing crossover pair every ten miles or so was (then) a good idea?

You don't want them much further apart. Currently you have got Upperby to Penrith at 17 miles in the down and effectively Carlisle to Penrith in the Up at slightly longer, you just can't get much through that in SLW. Tebay to Oxenholme is a good 14 miles too.

Any new provision would be box-worked now anyway; I think all the WCML former GF and EGF (except Quintinhill) are now on the box?

Clifton is released to a push button GF I think, Penrith is odd as it is electric pointwork operated by the box with no signalled routes IIRC.
--- old post above --- --- new post below ---

Ships said:
Even the planners weren't 100% sure which cross overs where there and which had been abandoned.

The cynical amongst us may argue that if it has rust on it then it isn't used much and therefore can be ripped up....

W230 · 13 Oct 2013

There's an emergency crossover operated by groundframe between the Up and Down at St. Helier on the Sutton loop.

Often used if there is a block on the line at Sutton. It's pilotman operated and works with SLW from St Helier to West Sutton, where they terminate and reverse services back towards Wimbledon.

Ships · 13 Oct 2013

The Planner said:
You don't want them much further apart. Currently you have got Upperby to Penrith at 17 miles in the down and effectively Carlisle to Penrith in the Up at slightly longer, you just can't get much through that in SLW. Tebay to Oxenholme is a good 14 miles too.

Clifton is released to a push button GF I think, Penrith is odd as it is electric pointwork operated by the box with no signalled routes IIRC.
--- old post above --- --- new post below ---

The cynical amongst us may argue that if it has rust on it then it isn't used much and therefore can be ripped up....

Yeah it's sad that sometimes that view is taken, I have go with the continental attitude of having far more engineers sidings dotted about and extensive use of cross overs and single line working.

The thing is I bet when some of these crossovers where taken out we still got sensible possessions on Sundays. Now with the much reduced access and the desire for 80mph hand back being able to hand back a road and use ALO so we can have extended access to tamp / use the DTS and/or AFM might be useful

Maxfly · 14 Oct 2013

Inverness has 3 GF's, 2 at culloden and one in the station for the triangle. The far north and Kyle lines have a multitude, one for each set of sidings (6 for Kyle & 16+ for the far north iirc) although not all are in use and there are still 6 on the screens of which 5 I believe have been removed, they were mainly for distillery access etc.

Crossforth · 14 Oct 2013

There is a ground frame at Neville Hill East Junction and it links onto the Down Hull.

moggie · 14 Oct 2013

The reason for using a GF in the past was to avoid the need for expensive remote interlocking connected by miles of cable or TDM to the signal box for what would have been a relatively small, infrequently used piece of infrastructure. Signals protecting GF's used to be classed as semi-auto, nowadays auto signals which are largely controlled via local line side circuits. If remotely controlled, movement sinto and out of the GF would likely be fully signalled by controlled signals - more signalling where a shunter would suffice .It made sense then and would now - perhaps.

Except many interlocking systems are no longer remotely based but centrally based with a distributed comms network to line side signals either side of the GF. The interlocking of the points could therefore be considered no more onerous to provide than any other. Power can be provided from batteries charged from the signalling supply. Yet still GF's are perpetuated when the previous constraints no longer exist. They even use power operated frames now with motor worked points thus negating previous constraints of inadequate power supply, hence the use in the past of mechanical frames. Simply, GF's in an otherwise fully signalled railway using modern line side signalling is perverse imho. It also imposes the need for a shunter on the FOC using the facility.

Joseph_Locke · 15 Oct 2013

The Planner said:
The cynical amongst us may argue that if it has rust on it then it isn't used much and therefore can be ripped up....

The truly cynical would take rusty GF rails as a sign that the track budget has been cut again, reducing the SLW usage ...

mainframe444 · 15 Oct 2013

There is a groundframe still in use at Melton Junction.

For those who don't know the history, there was at one time a signalbox here when the Melton-Nottingham mainline was in use. This was where the London-Nottingham mainline route via Melton diverged from the line to Leicester.

Today, the line from Leicester is the "main line" and the line towards Nottingham is singled, leading to the Test Track.

Trains arrive at Melton, from Leicester they will go into the loop beyond Melton to reverse, from Peterborough they reverse from the down to the up line.

Trains then make a wrong direction move towards Melton Junction on the up line, where the signaller is contacted to release the ground frame. A tylers key is used to unlock it, the points are changed and the train moves onto the up/down Asfordby line.

The levers in the frame are then returned to normal and the release taken back by the signaller.

When leaving the test track this is done in reverse.

MF

AlexS · 15 Oct 2013

moggie said:
The reason for using a GF in the past was to avoid the need for expensive remote interlocking connected by miles of cable or TDM to the signal box for what would have been a relatively small, infrequently used piece of infrastructure. Signals protecting GF's used to be classed as semi-auto, nowadays auto signals which are largely controlled via local line side circuits. If remotely controlled, movement sinto and out of the GF would likely be fully signalled by controlled signals - more signalling where a shunter would suffice .It made sense then and would now - perhaps.

Except many interlocking systems are no longer remotely based but centrally based with a distributed comms network to line side signals either side of the GF. The interlocking of the points could therefore be considered no more onerous to provide than any other. Power can be provided from batteries charged from the signalling supply. Yet still GF's are perpetuated when the previous constraints no longer exist. They even use power operated frames now with motor worked points thus negating previous constraints of inadequate power supply, hence the use in the past of mechanical frames. Simply, GF's in an otherwise fully signalled railway using modern line side signalling is perverse imho. It also imposes the need for a shunter on the FOC using the facility.

Perhaps one way to look at it is that with signallers controlling ever larger areas, in some cases it is not desirable for them to focus their attention on what could be repetitive shunt moves (particularly when forming up trains) when a shunter could be provided for marshalling purposes anyway? Horses for courses I guess?

fergusjbend · 15 Oct 2013

Are there any useful books or websites on signalling practice in Britain? I'm looking for something readily comprehensible to a non-technically minded lay person with an IQ of about 70.

Fergus

Ground Frames

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