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WGroleau 24th June 2020 19:10

Derailing devices
 
There are several abandoned rails near where I live. On one of them, there is a device which is obviously intended to derail anything passing it (and labeled as such).

The labeling indicates that it is commercially manufactured for that purpose, implying that there are many more in use somewhere. The size of the device indicates that the steel alone in it isn't cheap.

On another abandoned line, there is a derailed of a different style, but this one is on an active rail (a cement loading station is between it and the abandoned rail).

WHY would anyone intentionally spend that much money to derail trains?

tonyharker 24th June 2020 19:14

a. to stop runaway trains
b. to prevent movements which will cause a collision

DSY011 24th June 2020 22:01

Also used to protect workers on the line where they are not visible due to obstructions blocking the view until the last min. Yes, I know the driver should be going slow, but you can't stop a heavy load on a six-pence. (21/2P in todays money.)

aussiesteve 25th June 2020 03:22

G'day,
There are various designs employed for the purpose of derailing an errant train movement.
On main lines at crossing loops and refuges, a Catch Point is generally utilized.
This in the form of a switch rail blade which remains open to prevent anything passing and fouling the main line.
A deflection rail just beyond that switch blade ensures that the wheels of an errant movement is directed away from converging with the main running line.
And the switch blade is closed to permit correct movement out of the loop or refuge.
Within yards and sidings, derailers that sit ontop of the rail are generally utilized.
One version dubbed a Scotch Block.
This derailer has a formed groove to lift the wheel and flange above it and aim the wheel outside of the running rail.
The derailer generally pivots over to the side of the rail to permit correct movement during shunting etc.
Rail yards and sidings are rarely flat, in fact a slight gradient was employed at most yards to permit gravitating wagons during shunting movements.
Imagine a run-away cement wagon at the siding that you mentioned.
Without the provision of either a catch point or derailer, that wagon could roll towards the points onto the main line.
Yes, it would still derail as those points would be set for the main line.
But, the wagon would encroach the main line and present a potential collision risk to a train approaching on the main line.
One location on the NSW Blue Mountains which posed a challenge for heavy coal train crews was Lawson.
The coal train dropping down the 1 in 33 grade and directed into the UP refuge to permit a cross with an UP interurban pas job.
This refuge ONLY just long enough to fit a 33 hopper coalie with quad locos.
A catch point just feet beyond the Refuge starter did not provide any misjudgment and overrun.
Yes, the occasional train did overrun the signal and roll through the open catch points.
It would not go far and be jammed up against the cutting wall.
With much of the train still perched on the falling 1 in 33, only a short section of the refuge adjacent the station platform on level ground.
The loco brakes would NOT hold a 3300 tonner stationary, so you had to leave the train brakes applied.
I believe that one of the "incidents" occurred when the crew got off to go to the shops and had only left the train sitting with the loco brakes applied.
Gravity overcoming the loco brakes.
At the Kandos cement works on the Mudgee branch line, the yard was protected by a catch point that was infact the points to the old loco turn table.
The yard on a falling grade towards the main line.
I was working home from Mudgee one time and we were halted at Kandos works to assist with a run-away cement pot recovery.
The errant cement loaded cement pot had rolled out of the yard, through the points and over the old turn table and buried in the mud on the opposite side.
We detached our loco from the train, stabling it on the main line, and then shunted to enter the works yard and then aim towards the turn table.
The turn table was very wonky and booked out of service for yonks.
So, we could not go onto the turn table, but sit on the other side and use a heavy wire hawser attached to the cement pot to drag it back onto the rails.
Apparently, the hand brake on that cement pot was defective and it decided to roll away.
It is far better to derail an errant movement than incur a collision, especially with a passenger train.
Steve.

aussiesteve 25th June 2020 08:17

I have popped back to this threat, as I have uploaded a couple of photos into the Gallery.
The first showing the TRAD NSWR derailer which sits on top of the rail.
We nicknamed this type as a Lizard.
https://www.railwayforum.net/gallery...a_nsw_1985.jpg
A revolving disc shunt signal is attached to indicate which was the derailer is positioned.
A red target and light when the derailer is in position and cannot be passed.
A white arrow and light when the derailer is removed and can be passed.
It being worked from ground frame B.
This derailer in Tarana yard in NSW no longer exists, nor does the Down Starter upper quad semaphore.
There being no connection from the reduced yard at the west end to the main line today.
I had mentioned Lawson UP Refuge and how there is very little overrun from the Loop UP starter to the catch point.
https://www.railwayforum.net/gallery..._june_2002.jpg
While you cannot see that catch point in the uploaded photo, you can see the deflection rail associated with such.
Go past the stick and you are definitely in the dirt and going to cop aggro from management.
4500 tonner coalies of today are too long for the refuge so no longer get diverted in there.
I mentioned the cement pot run-away at Kandos works, and have uploaded the photo that I took at the time.
https://www.railwayforum.net/gallery...s_4_7_1989.jpg
I am standing on the main line (Mudgee branch) taking the shot of our 442 class weasel and the pot.
Over the years, there was more than one cement pot run-away and rattle over the old turn table.
At some stage, a STOP BLOCK was placed across the rails before the turn table.
That in an attempt to prevent the errant pots from crossing the table and getting buried in the mud.
I am not sure if the old turn table still exists, the Kandos cement works has been closed for 9 years.
Not all Loops possessed a catch point (jack pionts as we called them).
Mainly only those with potential overrun due to misjudgment of train handling.
One such being Tumulla Loop, perched halfway up the 1 in 40 Tumulla bank.
Eastbound trains dropping down the hill faced the run-away embankment catch points at the end of the loop.
And, out through them jacks did the train go that I was working as fireman on my first shift out on the road.
My driver had lost it on the approach to Tumulla loop and we became a run-away.
The incident scared the "you know what" out of me, and prompted RESPECT for steep hills for me.
Fortunately, the train did finally stop just before tragedy.
Barely 12 inches of metal remaining under the front wheels on the run-away road.
BUT, the lack of jacks at Geurie in NSW on the line from Orange to Dubbo contributed to a nasty prang.
In august 1963, westbound goods 669 was tabled to cross the eastbound Mail train W58 at Geurie.
W58 tabled through Geurie at 2033 / 2034, was worked by soot belcher 3817, 4-6-2.
Goods 669 on the night of the incident was worked by monster soot belcher 6003, 4-8-4+4-8-4.
The single line safe working system being Electric Train Staff token working.
Info available about the prang is limited.
To access the official incident report, you must pay the NSW State Archives mob, which I won't bother.
No fatalities occurred, though many cattle aboard the Mail were injured.
Many being cattle in the sleeper cars tumbling out of the top bunks.
The info spruiked states that train 669 reversed into the Loop from the Dubbo end.
However, the tail gunners caboose became foul at the rear end of the Sydney end loop points.
So, the goods moved forward to clear the rear end.
But, in doing so, passed the clearance post and fouled the main line at the Dubbo end.
The Garratt being so long that in the dark, the crew could not see that clearance post.
W58 approached and slammed into the partially foul front left side of the Garratt.
3817 derailing and ending up on it's side, the Garratt being shoved backwards and jack-knifing into the silos.
Attested speed being spruiked as at 20 MPH.
HMMMMMMMM.
The impact time being attested as at 2044, thus inferring that W58 was running ten minutes late.
HMMMMMMMM
Both soot belchers were subsequently written off and scrapped.
Had jack points existed at Geurie, then the pilot bogie of the Garratt would have derailed and slew away from the main line.
With the then UP Home semaphore signal being barely 300 feet from the Dubbo end Loop points, train 669 would have had to pass such to then reverse into the loop.
ETS rules dictate that to shunt outside of a Home stick, the ETS token for that section MUST be obtained.
That preventing an opposing train from entering the section while shunting is occurring.
DID they grab the Geurie to Wongarbon ETS peg to perform the shunt ?
IF so, that may account for the tardy W58.
Being tardy, was W58 train speed only 20 MPH when it slammed into the foul left side of the Garratt ?
The photos portraying the damage seem to infer a higher impact speed.
Regardless, the incident reinforces that any potential fouling of the main line can result in tragedy.
Steve.

WGroleau 18th July 2020 07:50

Thanks for explaining the reason for putting one on a line in use. Why would it be on an abandoned line? It is obvious that the line has not been used in decades, and someone would have to intentionally change a switch to get any cars onto the spur. (Not possible to get onto it from the other end.). Since I posted, I have seen two more of these things.

TRP 18th July 2020 09:26

Quote:

Originally Posted by WGroleau (Post 93955)
Thanks for explaining the reason for putting one on a line in use. Why would it be on an abandoned line? It is obvious that the lie has not been used in decades, and someone would have to intentionally change a switch to get any cars onto the spur. (Not possible to get onto it from the other end.). Since I posted, I have seen two more of these things.

I guess it could be on the abandoned line because either
a) it was already in situ before the line was abandoned and they have no reason to remove it or they feel the need to leave it there or
b) it may have been installed to prevent trains using the abandoned line, either intentionally or unintentionally

Tony

WGroleau 19th July 2020 01:59

Derailing sounds like a rather dangerous way to prevent access.

Beeyar Wunby 19th July 2020 15:32

Quote:

Originally Posted by WGroleau (Post 93964)
Derailing sounds like a rather dangerous way to prevent access.

Yes it absolutely is. There's a very real risk of injury or death to anyone on the train, particularly if the line speed is significant.

I was led to believe that you only derail a train if there's a risk of serious collision. Nowadays in the UK new installations are usually at depots (5 mph max) or freight lines, as TPWS should stop a train on the mainline before the point of collision.

Beeyar Wunby 5th August 2020 14:55

1 Attachment(s)
And here's a picture of one of the blighters (obviously train drivers hate derailers - they bring only sorrow).

This photo was taken at an EMU maintenance depot. The derailer is the yellow plate lying along the running rail - and is in the "career restructuring" position. Note the small CCTV camera which is pointed roughly at the device. This depot has been modernised and all train movements are controlled by a Yard Supervisor sitting behind a small signalling panel - the camera gives him a chance to check that the device is clear of the railhead before authorising a train movement towards the shed.

All roads into the shed have derailer protection, because although the speed in the shed is only 3MPH max, there are fitters/techs workling in/under/on top of & between vehicles. It's better to drop an errant unit into the dirt rather than have it hit a train that guys are working on the outside of.

HTH, BW


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