Curious "half-a-point" on old siding.

[Ken H]

Are there any unworked catch points still in existence? I recall the “fully fitted railway” being the phrase in the early 80s with the end of unfitted wagons.

I havent seen any for years. they have all gone from Settle/Carlisle.

 

[Joseph_Locke]

I havent seen any for years. they have all gone from Settle/Carlisle.

I doubt there are any unworked ones left at all, as they do not suit high(er) speed running at all.

NR had (well they did 6 years ago) have a national project in action removing all the worked ones too, as there are, as MadMac says, no "unfitted" trains to justify them and they cost money to maintain.

 

[Ken H]

I doubt there are any unworked ones left at all, as they do not suit high(er) speed running at all.

NR had (well they did 6 years ago) have a national project in action removing all the worked ones too, as there are, as MadMac says, no "unfitted" trains to justify them and they cost money to maintain.

what is a worked catch point? I thought they are all spring loaded and just sat there.

 

[edwin_m]

what is a worked catch point? I thought they are all spring loaded and just sat there.

On a single or other bi-directional line they had to be worked so that a legitimately signalled train in that direction wasn't derailed. Having said that they were probably rare on single lines as there usually wouldn't be a following train close enough to be at risk from a rollback. However one place that did have them was the line through Darwen, as desribed by this accident report:
http://www.railwaysarchive.co.uk/docsummary.php?docID=490

The train, a four-car diesel multiple-unit, had been diverted via a goods loop line to by-pass a set of worked catch points that had been giving trouble, and the driver had been instructed to pass the loop exit signal, which was being held at Danger by the failed points, and thence to proceed onto the single line again. The driver, after traversing the loop exit points at caution, allowed his train to accelerate on the steeply falling gradient to a speed of some 40 mile/h, when it arrived at a second set of worked catch points which were set wrong for it, and diverted it into a short spur terminating in a stop block.

 

[6Gman]

dont we ever learn?

https://en.wikipedia.org/wiki/Stafford_rail_crash_(1990) - train running into back of another doing permissive working.

Not sure the Plymouth and Stafford incidents are directly comparable.

 

[Dr_Paul]

I noticed the other day a catch-point on the avoiding line that comes off the up main at Clapham Junction and serves platform 7, just after the line leaves the up main, which prevents anything from running back on to the up main. What puzzles me is that the up track here is on a falling gradient so there is little danger of anything rolling backwards from platform 7. The line through platform 7 is not bi-directional, there is no connection from it on to the down fast, so it's not a trap-point protecting the up main from down services. The only explanation I can think of is that the line through platform 7 might be used as a shunting neck for stock moving in and out of the yard between the main and Windsor lines, and that a catch-point (or would it be a trap-point?) would be necessary to stop anything being shunted too far and fouling the up main.

 

[Ken H]

I noticed the other day a catch-point on the avoiding line that comes off the up main at Clapham Junction and serves platform 7, just after the line leaves the up main, which prevents anything from running back on to the up main. What puzzles me is that the up track here is on a falling gradient so there is little danger of anything rolling backwards from platform 7. The line through platform 7 is not bi-directional, there is no connection from it on to the down fast, so it's not a trap-point protecting the up main from down services. The only explanation I can think of is that the line through platform 7 might be used as a shunting neck for stock moving in and out of the yard between the main and Windsor lines, and that a catch-point (or would it be a trap-point?) would be necessary to stop anything being shunted too far and fouling the up main.

why would they need a catch point if all the stock is automatic braked.
or is it a trap to derail a train that spads* towards the main line?

* not Special Political ADvisorS!

 

[Dr_Paul]

why would they need a catch point if all the stock is automatic braked. or is it a trap to derail a train that spads towards the main line?

Good questions. The track-plan shows that it might be possible for something to come across from the West London Line and end up in the down direction on platform 7.

 

[edwin_m]

I noticed the other day a catch-point on the avoiding line that comes off the up main at Clapham Junction and serves platform 7, just after the line leaves the up main, which prevents anything from running back on to the up main. What puzzles me is that the up track here is on a falling gradient so there is little danger of anything rolling backwards from platform 7. The line through platform 7 is not bi-directional, there is no connection from it on to the down fast, so it's not a trap-point protecting the up main from down services. The only explanation I can think of is that the line through platform 7 might be used as a shunting neck for stock moving in and out of the yard between the main and Windsor lines, and that a catch-point (or would it be a trap-point?) would be necessary to stop anything being shunted too far and fouling the up main.

why would they need a catch point if all the stock is automatic braked.
or is it a trap to derail a train that spads* towards the main line?

* not Special Political ADvisorS!

Good questions. The track-plan shows that it might be possible for something to come across from the West London Line and end up in the down direction on platform 7.
View attachment 59979

The dashed lines on the Sectional Appendix are sidings where trains may be parked up, and which therefore need trap points under the rules whether they are dead ends or in this case can be entered from a running line at the far end (this would be at low speed and unlikely to be used for through movements). The automatic brake leaks off after a few hours without power and while trains should be secured by hand brakes there is always a risk of not enough being applied or of some being faulty, hence the need for trap points. The ladders of slips across these sidings are an unusual feature, but the interlocking is probably arranged so that when nothing is signalled in or out, the points are set to divert anything coming out of the sidings into the last one before the running lines. Another trap is shown in the siding, to derail anything that might otherwise enter the platform 7 loop when not signalled to do so.

In respect of Platform 7 I think Dr_Paul's first post has it right. The layout probably dates from the time when some trains were loco-hauled and empty stock could be propelled out of the sidings to reverse in 7 and head towards Waterloo. Even EMUs might have been driven from the back cab to do this, although I suspect that would now be forbidden. In either situation it would be very easy to push the tail of the train past the signal and in the absence of these traps into head-on collision with an approaching train heading for platform 6.

 

[BS56]

There used to be a catch point on the up goods loop at Broxbourne (Herts ) it may still be there as there has not been any track renewals there. The loop goes around the back of the marshalling sidings which can be seen from a down train if your on one. Although thinking about it it might also be a slotted joint which I mentioned above.

 

[Ken H]

One other track feature that may cause confusion is one of these
https://upload.wikimedia.org/wikipedia/commons/thumb/a/a6/Expansion_joint,_Hayle.jpg/240px-Expansion_joint,_Hayle.jpg (Pic of Continuous Welded rail expansion joint)

Its to allow for expansion, especially at the transition from CWR to welded track
Dunno if they are obsolete on Network Rail.
But I think one accident was when someone clipped one of these thinking it was the catch point. Of course the train derailed at the unclipped catch point. Think in a possession.

 

[edwin_m]

One other track feature that may cause confusion is one of these
https://upload.wikimedia.org/wikipedia/commons/thumb/a/a6/Expansion_joint,_Hayle.jpg/240px-Expansion_joint,_Hayle.jpg (Pic of Continuous Welded rail expansion joint)

Its to allow for expansion, especially at the transition from CWR to welded track
Dunno if they are obsolete on Network Rail.
But I think one accident was when someone clipped one of these thinking it was the catch point. Of course the train derailed at the unclipped catch point. Think in a possession.

CWR is welded track - did you mean jointed? Expansion joints are used between CWR and any track feature that can't withstand the stresses that CWR applies, such as older switches and crossings.