St Erth to St Ives line - ongoing discussion, including a book about the line (merged posts)

[whole diary]

[stuving]

Seeing that machine, I wonder why it's going to take a week to relay St Ives!

One thing these machines can't yet do is bring their own rails with them - these have to be brought in and placed in position first. That's not so bad for replacement, where the existing track can be used, and the rails kicked off the side of a train. For installation from scratch, or from track so bad it can't be used for a goods train, it must be quite a challenge. I think it means bringing in quite short lengths and welding on site, and in any case the whole length has to be temporarily joined across the gaps that will be finally welded only when tensioning is done.

Maybe the next development step of the machnes will be for that gantry that scoots back and forth the whole length of the train, carrying sleepers up to the front, to pull rails forwards from an even longer train-load of supplies. The gantry runs on rails attached to the sides of the wagons, which are continuous across the gaps between them while allowing for curves. I'm sure some kind of channel equipped with rollers can be included for rail handling too. Note that (at least in Balfour Beatty's one) there's a driver inside the gantry - I'm sure that's a more popular gig than the "seat" down at track level for the operator who appears to be supervising the clipping down of the rails.

[RailCornwall]

i'm hearing some good news that reviewed serviceable removed rail and sleepers are destined for the Helston Railway.

[Thatcham Crossing]

Presumably the fact that steel sleepers are being laid in an area with salty sea air has been considered?

[Electric train]

Presumably the fact that steel sleepers are being laid in an area with salty sea air has been considered?

They will last longer than the timber ones with cast iron chars, concrete is excessive for what is effectively a light railway

[rower40]

I found a quite recent video of the overall track laying process involving the Balfour Beatty new track construction train, (NTC^▸ (New Track Construction)).  It?s installing track on steel sleepers in this example, at Shildon, the machine can be seen at around 15 mins into the video.

https://youtu.be/vUd2kc-JsB8

It seems to me this machine is possibly more relevant to installing brand new track, or for single track replacement, but on double track a lot of replacement will still get done one side at a time by conventional road rail equipment working from the existing parallel track?

Paul

Seeing that machine, I wonder why it's going to take a week to relay St Ives!

It's done like this:

https://www.youtube.com/watch?v=jrmZIgVoQw4&t=111s

1m33 in, and onwards.

[paul7575]

Seeing that machine, I wonder why it's going to take a week to relay St Ives!

One thing these machines can't yet do is bring their own rails with them - these have to be brought in and placed in position first. That's not so bad for replacement, where the existing track can be used, and the rails kicked off the side of a train. For installation from scratch, or from track so bad it can't be used for a goods train, it must be quite a challenge. I think it means bringing in quite short lengths and welding on site, and in any case the whole length has to be temporarily joined across the gaps that will be finally welded only when tensioning is done.

Maybe the next development step of the machnes will be for that gantry that scoots back and forth the whole length of the train, carrying sleepers up to the front, to pull rails forwards from an even longer train-load of supplies. The gantry runs on rails attached to the sides of the wagons, which are continuous across the gaps between them while allowing for curves. I'm sure some kind of channel equipped with rollers can be included for rail handling too. Note that (at least in Balfour Beatty's one) there's a driver inside the gantry - I'm sure that's a more popular gig than the "seat" down at track level for the operator who appears to be supervising the clipping down of the rails.

On the Borders railway, they used a quite different (Dutch) machine, which effectively pulled long welded rail strings off the front of a rail delivery train, and pushed them ahead of itself, but it relied on the sleepers already being accurately positioned for hundreds of yards ahead in the direction of movement.  They also had a small tracked guidance machine right at the front, and temporary rollers.

A short Rail Engineer video, it?s the very last part:  https://youtu.be/VHWuTvpcco4
Much longer video: https://youtu.be/bSmkO0un5Go

It seems to me on single track you either have to lay the rails ahead of the sleeper delivery train, or lay the sleepers ahead of a rail delivery train, but it would be pretty much impossible to do both at once using a single machine travelling on rails...

Paul

[stuving]

On the Borders railway, they used a quite different (Dutch) machine, which effectively pulled long welded rail strings off the front of a rail delivery train, and pushed them ahead of itself, but it relied on the sleepers already being accurately positioned for hundreds of yards ahead in the direction of movement.  They also had a small tracked guidance machine right at the front, and temporary rollers.

A short Rail Engineer video, it?s the very last part:  https://youtu.be/VHWuTvpcco4
Much longer video: https://youtu.be/bSmkO0un5Go

It seems to me on single track you either have to lay the rails ahead of the sleeper delivery train, or lay the sleepers ahead of a rail delivery train, but it would be pretty much impossible to do both at once using a single machine travelling on rails...

Paul

I was going to say that (including the video) shows what I was proposing would be quite feasible. Couple that rail-handling machine and wagons to the back of the sleeper wagons, feed rails along/over/through those, and use similar small tracked vehicles and rollers to pull the rails out in front. Depending on gauge issues you might need to lose the bottom layer of sleepers to feed the rails through (on rollers and guided), but it all looks doable.

But I find that Plasser&Theurer have got there first (as well as a Chinese company and perhaps Harsco). Their biggest beast, the SVM 1000, can be configured in several ways, for replacement or for laying from scratch. They put a layer of rails under the sleepers on their adapted wagons (supporting the shuttle-gantry), though other descriptions have separate wagons for rails. I can't find a clear set of words or a video of it operating in this mode, but I suspect it does the pulling-out of rails and the picking them up and laying the sleepers as two separate steps. I also suspect they have never tried to down-size these machines of theirs for British gauge - not a trivial task.

That leaves one more operation that might be better done by train as it involves delivering something very heavy - laying the ballast. I can't see that being done by the same omnipotent machine, but I think it should be possible to lay track on bare soil and put the ballast underneath it afterwards with a separate big machine (possibly in two or more passes). I can imagine that it might take longer to get it tamped and stable afterwards, and the ground preparation would need to be adapted.

However, you need to be careful you are not going to a lot a effort and expense to mechanise something better (and cheaper) done by a bunch of blokes of above-average BMI with much simpler machines and tools. Plus, of course, laying brand-new track isn't that common.

[eightonedee]

In the light of the last few posts - what prospects of someone developing something better than the much-heralded machine that failed to deliver the goods on the Great Western Mail Line (GWML^▸ (Great Western Main Line)) electrification to deliver Over-Head Lines (OHL^▸ (Over-Head Line)) quicker and cheaper?



Edit: VickiS - Clarifying Acronyms

[Electric train]

In the light of the last few posts - what prospects of someone developing something better than the much-heralded machine that failed to deliver the goods on the Great Western Main Line (GWML^▸ (Great Western Main Line)) electrification to deliver Over-Head Lines (OHL^▸ (Over-Head Line)) quicker and cheaper?

The "clever" people who dreamt up the Over-Head Lines (OHL) factory train have mostly left the industry, we now have engineer in the industry with recent experience who have learnt the lessons of GWEP^▸ (Great Western Electrification Program) especially from a number of former British Rail (BR^▸ (British Rail(ways))) engineers who were involved in East Coast Main Line (ECML^▸ (East Coast Main Line)) etc that were brought in as consultants.



Edit: VickiS - Clarifying Acronyms

[RailCornwall]

So how practically will the work be done at St Ives, when the line ends at the buffers at the station. An explanation would be welcome.

[CyclingSid]

Probably not acceptable to Network Rail:
https://www.yorkshirepost.co.uk/heritage-and-retro/heritage/army-has-relaid-bridge-level-crossing-and-450m-track-wensleydale-railway-just-three-weeks-3002103
From another article it appears the Army's interest is that this is the railway that brings tanks into Catterick Garrison.
What I was looking for was the fabulous picture of an RE^▸ (Religious Education) track laying machine on the Longmoor Military Railway, not to modern H&S^▸ (Health and Safety) standards but a typical Army pragmatic solution.

[Electric train]

So how practically will the work be done at St Ives, when the line ends at the buffers at the station. An explanation would be welcome.

The sleeper laying train will work as close to the line end as it can, also when the Maidenhead - Bourne End was relayed last year the platform areas have concrete sleepers which were laid by RRV^▸ (Road Rail Vehicle) (Road Rail Vehicles) effectively track panel by track panel (60 ft ish)

[TonyK]

But I find that Plasser&Theurer have got there first

There is plenty of video of the Plasser machine in action, including this piece in Sweden.

In the light of the last few posts - what prospects of someone developing something better than the much-heralded machine that failed to deliver the goods on the GWML^▸ (Great Western Main Line) electrification to deliver OHL^▸ (Over-Head Line) lines quicker and cheaper?

It seemed to me at the time that the fault lay not with the Over-Head Lines (OHL) train but with whoever thought it was appropriate for the particular job in hand. I may well have this wrong and look forward to correction, but I recall that it worked according to what it said on the tin. There were lots of issues with stuff that had been buried along the lineside without being recorded, such as a massive internet outage when it punched a gantry base through a fibre optic cable, and signal cables being cut. Some of the tracks weren't in the same position as when someone last updated records, and we were left with exploratory digging having to be done by men with shovels. On a lovely virgin railway, with all the add-ons routed neatly through proper conduits, it might well have accomplished the claimed 1.6 Km per overnight shift, but the real world proved to be a more challenging environment. I would hope that we got our money back, but somehow, I doubt it..


Edit: VickiS - Clarifying Acronyms

[RailCornwall]

from Network Rail Western on Twitter.

[bobm]

Lovely photos, but torture we can't go to see for ourselves!