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Ground Frame Release Question


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Afternoon all,

 

Picture if you will, a token worked freight only branch. Within this branch is a loop with 2 crossovers. Let’s say east and west for arguments sake. As I understand it, the west ground frame can be released by Annett’s key (or similar), but how would the east ground frame be released? Is it possible that the west ground frame could have a separate mechanical or electrical  release for the east so both could be used at the same time?

 

Thanks for any help!

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If the branch is worked by token and there are locked ground-frames, then they would be unlocked by the token. There might be one central GF working both connections, or - probably more likely - one GF at each connection. If the latter, then clearly only one GF can be used at any one time.

Edited by RailWest
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If there was an operational need to work both connections at once, and that is a big "if", the nominated master ground frame could include an Annett's Key, locked into the GF unless the GF has been released by the single line implement (tablet, token or staff). Once the GF has been released, the Annett's Key can be removed to release the other GF in turn. Everything has to be returned to its normal position before the single line implement can be released from the master GF to allow traffic to resume. The LNWR, which held a blanket licence from S&F for the use of Annett's Keys, was fond of this arrangement, occasionally locking a whole sequence of GFs with AKs released in turn.

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Thanks for the informative replies everyone. 
As a bit more background, this would be in a late 70s early 80s BR WR setting. 
Interesting to hear that handpoints are acceptable as it’s freight only. Would this mean throw off points wouldn’t be necessary on any sidings?

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14 hours ago, cold-ash said:

Thanks for the informative replies everyone. 
As a bit more background, this would be in a late 70s early 80s BR WR setting. 
Interesting to hear that handpoints are acceptable as it’s freight only. Would this mean throw off points wouldn’t be necessary on any sidings?

If we assume late '70s/early '80s the connections are almost inevitably going to be ground frame worked especially if the line is busy and or is used by (then) modern heavy wagons.  I can't think of any locations on the Region at that time where running line connections on such lines, particularly where existing signalling was being removed, where the points were not worked by ground frames and it was not unlikely, even on a freight only line that the points also had facing point locks.  the ground frames would be released by token.

 

When the new link to Whatley Quarry was put in c1974/75 the new passing loop at Hapsford had ground frame operated points with facing point locks because the line was used by heavy stone trains (the provision of facing point locks on running line on new work points on freight only branches was WR Regional policy at that time).  The same applied to new connections on the Merehead quarry line but at Cranmore, where the heaviest vehicles were 45 ton tank cars the points had hand levers because speeds were low.  It really depends to some extent on what the line was being used for and how frequent trains were.    The provision of trap points, or not, would depend very much on what took place in the sidings and, again, how busy the line was as well as the gradient.  For example the old connection to the original exchange sidings at Hpsford had an FOPL in the running line end and a trap at the sidings end - which was just as well in view of the number of times vehicles ran away there.  When the new line to Whatley Quarry was provided a trap point was provided in the single line at Whatley because there was a stretch of falling gradient from the quarry itself.

 

So think of the traffic, think of any gradients, think of teh frequency of trains - and so on - and you would be very likely to finish up with ground frame worked points with an FPL on the running line end of the connection. 

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Thanks very much Stationmaster. 
 

Two separate ground frames sounds like the most likely scenario for my situation.

 

thanks again for all the replies

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