Problems with IET trains from April 2021

[whole diary]

[stuving]

A further snippet of real information from Clarence Yard is that the material in question is A7N01S-T5 and its suitability for the corrosive environment is in question. That's obviously eminently Googleable, and the top hits mostly say this is an alloy much used in high-speed train bodies, and it suffers from stress corrosion cracking (SCC^‡(resolve)). The alloy's main components, other than aluminium, are zinc, magnesium, manganese, plus variable amounts other elements. The corrosion usually comes from chlorides, but apparently the process inside the cracks involves hydrogen.

This form of cracking does specialise in sudden failures, unexpected because the cracking is internal, so maybe we should be thankful that it was spotted before that happened. It has been known for ages, but by all accounts it is still hard to predict or control, or even to find by inspection. Hitachi's job was of course to manage all such risks, including the hard ones, so there's no excuses there - except, perhaps, in a specification that wasn't accurate. But could the UK^▸ (United Kingdom) train environment for all fleets (i.e. not just the 802s that venture past Dawlish) be saltier than elsewhere (e.g. Japan), and than was specified? That doesn't sound likely ...  but we must await further intelligence.

[TonyK]

A further snippet of real information from Clarence Yard is that the material in question is A7N01S-T5 and its suitability for the corrosive environment is in question. That's obviously eminently Googleable...

Indeed, and it seems to gave been a favourite research topic for the budding metallurgist (not me - guitarist once) or stress engineer for quite a few years. I read a bit of this paper from 2016. I have no idea what it says, other than that hydrogen can be an issue as you said. The pictures are good, though equally meaningless to my untrained eye. The point is, though, that one assumes all these matters were considered, and the choice of alloy was deemed sufficient for the job awaiting it. That will be occupying minds for some little while.

[grahame]

From JourneyCheck:

Saturday 15 May

"A number of Class 800 series Hitachi trains in use by several train companies, including GWR^▸ (Great Western Railway), were withdrawn from service earlier this week as a precaution. After completing rigorous safety checks, we will begin reintroducing train services. Trains on some routes will be less frequent than usual, and your journey might take longer than it normally would. "

"We're running a reduced timetable as we reintroduce services after safety checks. Trains might be busier than normal. Check your journey before you travel."

Local and regional trains are not affected and will continue to run as normal.
 
There are no through services between London Paddington & Cheltenham Spa.
 
A shuttle service will operate between Swindon and Gloucester only where onward connections are available.

The direct train which normally runs between London Paddington, Reading, and Oxford for stations via Evesham to Worcester, Great Malvern and Hereford has been withdrawn. A revised service will run along the Oxford - Evesham - Worcester route.

An hourly service will operate between London Paddington and Bristol Temple Meads.
 
Extra shuttle trains will run between Swindon, Didcot Parkway, Reading, and London Paddington.

Most GWR long distance services between London Paddington and Penzance via Exeter St Davids & Plymouth are expected to operate.

Most GWR long distance services between London Paddington and Swansea via Bristol Parkway & Cardiff Central are expected to operate.

[grahame]

JourneyCheck this morning (Sunday 16th May 2021) - no new line updates, but the reports are timestamped this morning.  Amended trains are in the journey planners.   In brief:

* London to Swansea, London to Bristol, London to Plymouth running about hourly
* Shuttle services running Oxford to Worcester,  Swindon to Cheltenham Spa, Bedwyn to Reading

There are a few reported "shortforms" such as

11:30 London Paddington to Paignton due 14:59
Facilities on the 11:30 London Paddington to Paignton due 14:59.
This is due to more trains than usual needing repairs at the same time.
Will be formed of 5 coaches instead of 9.

[broadgage]

With UNCONFIRMED reports suggesting that "dozens" of GWR^▸ (Great Western Railway) IETs^▸ (Intercity Express Train) are unavailable, it seems very surprising that an only slightly reduced service is being offered.

So is the only slightly reduced service  a "fiddle" achieved by declaring a significantly reduced service to be the "new normal"
Or are more IETS available than has been suggested ?
As well as the issue of cracks, I would expect a few units to be unavailable due to routine servicing and unrelated random mechanical faults.

So, so does anyone have actual figures for GWR IETs
1)number of units available for use.
2)number of units stopped due to cracks.
3) number of units unavailable due to routine servicing or unrelated mechanical failures.

And other data, such as reasonably expected changes in the above.

I appreciate that some members feel that my remarks about these trains are unduly frequent, or overly critical, and am therefore limiting such remarks.

[stuving]

From yesterday, we had a figure of 54-60 out of 93 (58 5-car and 35 9-car) units expected in service.Those are full fleet numbers, so there's no margin for maintenance or failure.

Now the man on the spot, Clarence Yard, has just given an update on railforums - 59 now with more to be added during today. That can only mean that some of those previously signed off long-term sick have been given a fit note. That's not unreasonable, given that the general strategy has been a precautionary one: stop trains on suspicion, and then look for evidence that they can, after all, be operated with close monitoring.

[grahame]

I don't have answers to your questions, but I've been practicing being a politician and answering a different question in such a way you won't notice it's not what you asked.   Ooops ...  

Comparing what was expected for Summer 2021 when the December 2019 timetable was introduced, you may see:

2 an hour Bristol to London via Parkway Superfast - 8 trains not running
Still running 2 an hour via Chippenham

1 an hour Cardiff to London - 4 trains not running
Still running hourly Swansea to London
Also electric shuttle London to Swindon

1 an hour Bedwyn to London - 3 trains not running
Running electric to Newbury for turbo shuttle

1 every 2 hours semifast Exeter to London - 3 trains not running
Alternate Plymouth exprsses calling between Reading and Taunton

1 an hour London to north Cotswold line - 6 trains not running
Turbo shuttle Oxford to Worcester

1 every hour Cheltenham Spa to London - 5 trains not running
Turbo shuttle Swindon to Gloucester
Also electric shuttle London to Swindon

I make that about 30 IET^▸ (Intercity Express Train) diagrams, with perhaps half a dozen each of Turbo and 387 diagrams filling in with shuttles.  What normality you compare to, though, is an interesting question. It might very much depend on traffic levels when and where 5, 9 and 10 cars were  expected to be needed and will be expected to be needed this summer.  Or indeed whether a 15 minute Paddington to Swindon service rather than a 10 minute service is adequate for a while.

I wonder where the turbos are coming from ... units that will be required for MetroWest, perhaps, or is there a risk of 2 cars on the Summer Saturday Weymouth trains?

Details / correction to the above welcome.

[Lee]

I appreciate that some members feel that my remarks about these trains are unduly frequent, or overly critical, and am therefore limiting such remarks.

At least no-one can accuse the trains themselves of being "unduly frequent" !

[IndustryInsider]

I expect Tornado will be kept in steam just in case.

Several crystal ball predictions looking on shaky ground.

[ChrisB]

My understanding from prior to this problsm was that 70 IET^▸ (Intercity Express Train) units are required to service what would have been the new May timetable on a werkday. So 59 is only 11 short of that requirement whicjh in no one’s vocabulary could be described as “dozens”

[Timmer]

Looks like the Paddington-Exeter/Plymouth/Paignton semi fasts are running next week.

[stuving]

There's now a picture of the new phase 2 cracking, but first here's the one from phase 1 in April again (the previous picture has vanished). This was "liberated" from the NIR (national incident report) that prompted all 80x and similar fleets to be examined. As always any comments of mine can only be superficial.

That looks to me like fatigue cracking in form, and its location isn't so unlikely given the oscillating loads on it. The bracket under that piece attaches not only the yaw damper bracket but also a vertical link to the anti-roll bar, which is probably more relevant in this context. (I'm sure there's a vertical damper or two somewhere as well, but haven't spotted them yet.)

While I did think at first that was a single casting, on second thoughts (and looks) there is weld metal visible behind the screw head (or nut). The whole bolster may even have been made from many little plates, all welded, like they were cut from a sheet of balsa with an X-acto knife and glued.

The picture of the phase 2 crack apparently was put out by Mark Hopwood on LinkedIn - for some reason. What strikes me about that is how straight it is, like two pieces of metal placed next to each other for welding but next fixed. Or, perhaps, that the weld was made on the other side, and has cracked allowing the join this side to move.

In this case there no obvious source of the kind of cyclic stresses that would lead to fatigue. That probably explains the initial precautionary overreaction, and the accompanying chorus of scratched heads.

[RailCornwall]

Not a regular user of Sunday Evening services, but looking at tiger tonight it seems a fairly full service is operating across Cornwall this evening. Tomorrow will be telling.

[IndustryInsider]

There’s been a lot of stock movements today, IET^▸ (Intercity Express Train)’s and other, to try and get everything back to where it needs to be for tomorrow.  I doubt it’ll be perfect, but hopefully far better than many, including myself, envisaged a few days ago.

[broadgage]

I don't have answers to your questions, but I've been practicing being a politician and answering a different question in such a way you won't notice it's not what you asked.   Ooops ...  

Comparing what was expected for Summer 2021 when the December 2019 timetable was introduced, you may see:

2 an hour Bristol to London via Parkway Superfast - 8 trains not running
Still running 2 an hour via Chippenham

1 an hour Cardiff to London - 4 trains not running
Still running hourly Swansea to London
Also electric shuttle London to Swindon

1 an hour Bedwyn to London - 3 trains not running
Running electric to Newbury for turbo shuttle

1 every 2 hours semifast Exeter to London - 3 trains not running
Alternate Plymouth exprsses calling between Reading and Taunton

1 an hour London to north Cotswold line - 6 trains not running
Turbo shuttle Oxford to Worcester

1 every hour Cheltenham Spa to London - 5 trains not running
Turbo shuttle Swindon to Gloucester
Also electric shuttle London to Swindon

I make that about 30 IET^▸ (Intercity Express Train) diagrams, with perhaps half a dozen each of Turbo and 387 diagrams filling in with shuttles.  What normality you compare to, though, is an interesting question. It might very much depend on traffic levels when and where 5, 9 and 10 cars were  expected to be needed and will be expected to be needed this summer.  Or indeed whether a 15 minute Paddington to Swindon service rather than a 10 minute service is adequate for a while.

I wonder where the turbos are coming from ... units that will be required for MetroWest, perhaps, or is there a risk of 2 cars on the Summer Saturday Weymouth trains?

Details / correction to the above welcome.

That number of trains that are "not running" but that do not count as cancellations does sound to me like a fiddle to make things look better than they are.

And the report that GWR^▸ (Great Western Railway) are only short of 11 IETs is better than the "dozens" suggested elsewhere but it is still a significant shortfall.