Class 455 Mishap - Battersea Park (07/10)

[FordFocus]

Given the rule book allows some concessions with regards to isolated, unbraked vehicles provided it's a bar coupler then I definitely think the industry will look at the event in greater detail.

 

[physics34]

But not like that! Coupled & uncoupled using the tightlock, yes, that's normal, not using this method it's not.

There should be at least 4 substantial bolts holding that together and the bolts are held in with locking nuts & IIRC locking pins as well to prevent them working loose. So something serious has happened.

However I believe that it could be quite prejudicial to any enquiry & it could be quite dangerous to speculate on what went wrong with this and what the failings are/were.

yeh but the forces involved with coupling units will inevitably affect the fixed bar coupling too i wouldve thought. over time.... or at least the bolts.

 

[A-driver]

Wow. I've seen trains break apart in service before including a potentially serious incident when a 317 came apart outside Hitchin but have never seen a semi-permanently coupled carriage break apart.

I have very strong suspicions what happened here but don't like speculating before the report comes out.

 

[physics34]

The units were on the Up Slow all the way up from Streatham Hill Down Siding, so there was no crossover. That makes it all-the-more worrying!

I often notice a similar sort of jolt on the 313s when taking power.

im not sure the jolt is just a warn camshaft or something but it does seem worse if the motor coach is the 3rd rather than the 2nd coach, if you are at the front....

 

[HarleyDavidson]

yeh but the forces involved with coupling units will inevitably affect the fixed bar coupling too i wouldve thought. over time.... or at least the bolts.

Fixed bar couplings are only ever undone by T&RSMD staff using specialist tools, they don't normally come apart at any other time than in depot for maintenance.

 

[redbutton]

Wow, that's quite an image.

I'm glad that unit was ECS, even more so considering that there's a 750V connection between those two carriages.

Surely the RAIB will want to investigate this given the potential consequences and the perceived rarity of such an event?

 

[SpacePhoenix]

https://paulbigland.files.wordpress...5-conversion-wimbledon-park-depot-30-6-14.jpg

Would the actual coupling bar be bolted onto that? Is the actual coupling bar a solid piece of metal or a hollow tube?

 

[Crossover]

Wow, that's quite an image.

I'm glad that unit was ECS, even more so considering that there's a 750V connection between those two carriages.

Surely the RAIB will want to investigate this given the potential consequences and the perceived rarity of such an event?

I don't think 455's have a power bus, do they? Isn't all the main electric kit (including collection and motors) on coach 3?

 

[A-driver]

I don't think 455's have a power bus, do they? Isn't all the main electric kit (including collection and motors) on coach 3?

They are bus wired unlike 313s. The 455s have shoes at each driving trailer so the 750v is bus wired to the motor coach which is in the middle.

 

[tsr]

455s on southern get coupled and uncoupled on a very regular basis, there must be alot of strain on inter-unit couplers/bars.. you can actually feel a bit of "give"/play on many southern 455s when taking power... they jolt a bit when they first move..a sign that there is wear and tear there.
--- old post above --- --- new post below ---


rough-ish set of points north of battersea park but nothing out of the ordinary...... if the units came from the up fast to the up slow they are rougher still.... 40mph max speed over those points but still nothing to get excited about

Battersea Park Jn feels OK at the moment - there've been a few ESR/TSR issues round there recently but I've been over it during various passenger and ECS moves recently and couldn't really significantly complain. In any case, as below, it does really seem that in any case the service was on the Slows from Battersea Park and had not reached any point where it could diverge at Battersea Pier Jn (incidentally, the way I remember the junction names is that Battersea Park = land, Pier = water, and pick what you're closest to).

 

[furnessvale]

But not like that! Coupled & uncoupled using the tightlock, yes, that's normal, not using this method it's not.

There should be at least 4 substantial bolts holding that together and the bolts are held in with locking nuts & IIRC locking pins as well to prevent them working loose. So something serious has happened.

However I believe that it could be quite prejudicial to any enquiry & it could be quite dangerous to speculate on what went wrong with this and what the failings are/were.

As you say, speculation is dangerous but I doubt an official enquiry will be swayed by us.

So I will speculate a little. Did the 4 bolts fail or was the bar coupling pulled completely out of one carriage.

Many failures on US railroads involve the whole coupling being pulled out of one of the wagons rather than the coupling parting, bar or otherwise.

 

[SpacePhoenix]

They are bus wired unlike 313s. The 455s have shoes at each driving trailer so the 750v is bus wired to the motor coach which is in the middle.

https://www.youtube.com/watch?v=qaqfm2OpuPs

Pause it at 3:46

 

[redbutton]

I imagine the cause will be either human error relating to maintenance, or some kind of fatigue issue relating to the high frequency of attachment pull-away tests.

The motor coach is coach 3, so I can imagine a pull-away test puts a fair amount of strain on not only the tightlock but the rigid-bars between coaches 1/2 and 2/3. I wonder how often those get inspected?

 

[HarleyDavidson]

As you say, speculation is dangerous but I doubt an official enquiry will be swayed by us.

So I will speculate a little. Did the 4 bolts fail or was the bar coupling pulled completely out of one carriage.

Many failures on US railroads involve the whole coupling being pulled out of one of the wagons rather than the coupling parting, bar or otherwise.

You never know who's watching and reading.

 

[physics34]

Fixed bar couplings are only ever undone by T&RSMD staff using specialist tools, they don't normally come apart at any other time than in depot for maintenance.

i mean when units gets coupled together..

 

[A-driver]

https://www.youtube.com/watch?v=qaqfm2OpuPs



Pause it at 3:46

Why? What does it say? As far as I can see it backs up what I say that 455s have a bus wire...

 

[HarleyDavidson]

They have what's known as a power train line or PTL to connect the 4 shoes on each DT to the motor coach.

 

[A-driver]

They have what's known as a power train line or PTL to connect the 4 shoes on each DT to the motor coach.

A power unit line and bus wire are pretty much the same thing. Basically a 455 has shoes at either end linked with the motors in the middle. If you gap the rear shoe but front one is still in contact you still get full power. A 313, on the other hand, dosnt have this. So if you gap the shoe on the A end you loose A end motors, A end headlight/heating/coach lights etc and the compressor. If you gap the B end shoe you loose b end motors, battery charging and all direct 750dc feed systems like heating, headlight etc. that end.

But 455s have a jumper between coaches (but not units) which carries 750v. This jumper dosnt exist on a 313-only get a 110v jumper.

 

[cjmillsnun]

i mean when units gets coupled together..

I really doubt that the forces involved in coupling and uncoupling would affect the fixed bars that much. If it did, this would likely have happened a lot more than this.

Lets be blunt, this is a freak occurrence. It is extremely rare for this type of coupling to come apart like this.

 

[RichardKing]

A line block has now been put on Platforms 10 and 11 at Victoria (and possibly Platform 9). I'm assuming this means the 455 unit involved in the earlier incident is due to be moved to a depot?

 

[Yabbadabba]

So I will speculate a little. Did the 4 bolts fail or was the bar coupling pulled completely out of one carriage.

I would from the pictures I've seen on the intranet it's not as simple as your speculation. I look forward to reading the report on this one if its investigated. All I know is it made my job very busy and sometimes very quite at times.

 

[tsr]

A line block has now been put on Platforms 10 and 11 at Victoria (and possibly Platform 9). I'm assuming this means the 455 unit involved in the earlier incident is due to be moved to a depot?

1H62 is on 9 so not that one as well. I should imagine the block will likely coincide with a specific power isolation and may be to allow the RAIB / Southern / any other parties involved (if indeed RAIB are investigating) to inspect the train and make it safe to remove. If an additional inspection in situ is needed then I am not sure what this would entail time-wise. It may be deemed most practical to run the train to Stewarts Lane as 455s are currently maintained there and it is closest.

 

[RichardKing]

1H62 is on 9 so not that one as well. I should imagine the block will likely coincide with a specific power isolation and may be to allow the RAIB / Southern / any other parties involved (if indeed RAIB are investigating) to inspect the train and make it safe to remove. If an additional inspection in situ is needed then I am not sure what this would entail time-wise. It may be deemed most practical to run the train to Stewarts Lane as 455s are currently maintained there and it is closest.

That makes sense! I noticed, after posting the comment, 1H63 was using 9 to form 1H62.
The inspection of the train shouldn't be under too much time-pressure as no units are due to berth in either platforms overnight (tomorrow should get off to a good start - fingers crossed!) There will be a good few platform alterations this evening to contend with though!

 

[Townsend Hook]

1H62 is on 9 so not that one as well. I should imagine the block will likely coincide with a specific power isolation and may be to allow the RAIB / Southern / any other parties involved (if indeed RAIB are investigating) to inspect the train and make it safe to remove. If an additional inspection in situ is needed then I am not sure what this would entail time-wise. It may be deemed most practical to run the train to Stewarts Lane as 455s are currently maintained there and it is closest.

I would be very surprised indeed if the RAIB were not investigating. As has been pointed out, a coupling failure like this can potentially have fatal consequences.

 

[physics34]

its gonna take a while to recover the coaches closet to the buffer stops..... nothing can couple to them!!

 

[Townsend Hook]

Just spoken with an acquaintance of mine from Southern Engineering, he tells me that the tail pin holding one of the couplers to the coach sheared.

 

[Crossover]

its gonna take a while to recover the coaches closet to the buffer stops..... nothing can couple to them!!

Could it be moved under its own power (piloted from the broken end, driven from the other)?

 

[Chris M]

Could it be moved under its own power (piloted from the broken end, driven from the other)?

I expect that identifying whether that is safe will be the primary purpose of the inspection. If they have to move/remove any bits before they can do this then the RAIB (assuming they are involved) will want to observe this happening so nothing goes missing (I'm not suggesting this would happen deliberately) and there are photographs and measurements of how things were before it happened.

If it can't be moved under it's own power then someone is going to have to think outside the box.

 

[furnessvale]

Just spoken with an acquaintance of mine from Southern Engineering, he tells me that the tail pin holding one of the couplers to the coach sheared.

As I speculated. Often a weaker link than the four bolts at the centre of the bar.

 

[DelW]

Could it be moved under its own power (piloted from the broken end, driven from the other)?

Given the possible exposed/broken wiring where the set broke apart I would have thought it would be risky to apply power to it.

Presumably the rescuing set is still between the casualty and the buffers so could push from the rear, but that would still need someone standing in the damaged corridor end which has safety implications in itself.