Great Western Electrification Progress

[SamYeager]

With regards to the Severn Tunnel itself, I’ve heard some scare stories and rumours as above of permanently earthing it; and also completely contrary rumours that the “fix” required isn’t that difficult; they’ll have to suffer a greatly reduced lifespan (numbers of 5-10 vs 30 years mooted) of the conductor rail system currently installed; and at whatever point x years down the line that turns out to be they’ll renew it with something that will have a much better resilience to the conditions.

So another bout of several weeks closure of the tunnel in less than 10 years. Marvellous!

 

[paul1609]

Thank goodness we have Dft supervision to insist on bi modes, if this had been left to the rail industry or BR wed have electric trains terminating at Pilning with passengers transferring to a pacer for Cardiff ;}

 

[Grumbler]

Thank goodness we have Dft supervision to insist on bi modes, if this had been left to the rail industry or BR wed have electric trains terminating at Pilning with passengers transferring to a pacer for Cardiff ;}

What's wrong with rope haulage or Brunel's atmospheric system?

 

[Envoy]

I would have thought it absolutely vital that the Severn Tunnel is electrified in order to remove fumes - which I have smelt in the carriages.

 

[Jpeg]

Platform extensions ongoing at Slough

 

[traji00]

Platform extensions ongoing at Slough

View attachment 67035 View attachment 67036 View attachment 67037

Thanks for the share.
Is there a list of platforms requiring extension available?

 

[Dai Corner]

Thank goodness we have Dft supervision to insist on bi modes, if this had been left to the rail industry or BR wed have electric trains terminating at Pilning with passengers transferring to a pacer for Cardiff ;}

If decisions had been made on purely technical and commercial grounds without any political interference the electrification may have reached Temple Meads, by both routes, but not Wales.

 

[MarlowDonkey]

Is there a list of platforms requiring extension available?

I think most of the stations out to Reading are scheduled eventually to have extensions to cope with full length Crossrail trains. GWR are already operating 12 car 387s on peak hour commuter services. At Maidenhead, only about 8 or perhaps 9 cars can be accommodated in the platforms. The Slough extensions look as if they are designed to take 12.

The existing service of 8 car 387s on the Reliefs has selective door opening for 6 or 7 coaches at many stations.

 

[MarlowDonkey]

No, the current line speed for electric trains is, and always has been 60. It is being raised to 110 for electrics. The Diesel speed limit has been 125mph since the 1970s, and isn’t changing.

It's the presence of a level crossing nearby that's really the problem isn't it? Wires have to be at the lowest tolerance to get under the bridge and at the highest for safety reasons at the crossing. The question being whether the pantographs can cope at speed with the change of height over a short distance. There was some reason why it wasn't possible, or too expensive to remove the level crossing instead.

 

[hwl]

I think most of the stations out to Reading are scheduled eventually to have extensions to cope with full length Crossrail trains. GWR are already operating 12 car 387s on peak hour commuter services. At Maidenhead, only about 8 or perhaps 9 cars can be accommodated in the platforms. The Slough extensions look as if they are designed to take 12.

The existing service of 8 car 387s on the Reliefs has selective door opening for 6 or 7 coaches at many stations.

Lots of platform extension and DOO camera (wireless connection to in cab monitors) fitting going on this autumn. Touch and go (only 1 "spare" weekend) whether all will be ready for December TT change and TfL Rail take over, working being focused on the busiest stations.

 

[swt_passenger]

Thanks for the share.
Is there a list of platforms requiring extension available?

From the March 2019 enhancement plan:

“4 car
Appleford – Platform 1 and 2.
Aldermaston – Platform 2.
Bramley – Platforms 1 and 2
Mortimer –Platform 1
8 car
Tilehurst – Platforms 1, 2, 3 and 4
Pangbourne – Platforms 1 and 2.
Goring and Streatley – Platforms 1, 2, 3, 4
Cholsey – Platforms 1, 2, 3 and 4.
Culham – Platforms 1 and 2.
Radley – Platforms 1 and 2.
Reading West – Platform 2.
Theale – Platforms 1 and 2.
Thatcham – Platforms 1 and 2.
Iver –Platforms 4 (resurfacing)
12 car
Slough – Platforms 2, 3, 4 and 5.
Maidenhead – Platforms 1, 2 ,3, 4 and 5.
Twyford – Platforms 1, 2 and 3.
Didcot - Platform 3 – (funded by IEP).”

Hope this helps

 

[coppercapped]

I would have thought it absolutely vital that the Severn Tunnel is electrified in order to remove fumes - which I have smelt in the carriages.

Wimp!

You should have gone through it steam days and met a freight going the other way...

You don't know what clean air is!

 

[stj]

I was on a 158 a few years ago after a steamer had gone through and may passengers were concerned including the conductor until I explained what the haze and smell was.

 

[SamYeager]

From the March 2019 enhancement plan:

Somewhat surprised to discover the other day that the down platform at Bath Spa only accommodates 8 carriages despite that platform having been extended. No wonder coach A was quiet.

 

[Envoy]

Wimp!

You should have gone through it steam days and met a freight going the other way...

You don't know what clean air is!

It has been suggested that part of the problem of corrosion of the new equipment is not just the damp in the tunnel but also the fumes from diesels reacting with the damp. That being so, just think what it is doing to our lungs. If all the trains were electric in the Severn Tunnel, I do wonder by how much the problems of overhead line corrosion would be negated?

 

[GRALISTAIR]

All diesel fuels contain traces of sulfur. So sulfur dioxide and trioxide are produced which react with moisture to form sulfurous and sulphuric acid. Without data and experimentation I can not prove this is massively exacerbating the corrosion. However, the basic premise that 100% electric would massively reduce the issue I do agree with.

 

[coppercapped]

It has been suggested that part of the problem of corrosion of the new equipment is not just the damp in the tunnel but also the fumes from diesels reacting with the damp. That being so, just think what it is doing to our lungs. If all the trains were electric in the Severn Tunnel, I do wonder by how much the problems of overhead line corrosion would be negated?

All diesel fuels contain traces of sulfur. So sulfur dioxide and trioxide are produced which react with moisture to form sulfurous and sulphuric acid. Without data and experimentation I can not prove this is massively exacerbating the corrosion. However, the basic premise that 100% electric would massively reduce the issue I do agree with.

If one spent all day, every day in such an atmosphere it might have some effect on one's lungs - but the effect will vary from person to person.
The normal passenger train takes about 4 minutes to pass through the Severn Tunnel, and the passengers are in an enclosed tube so the levels of pollution will only build up over a period as the ventilation system draws in replacement air. After four minutes the ventilation system is drawing in clean air again.

For a commuter making a return trip by train every working day that is 8 minutes a day exposure to a level of pollution which is less than the level in the tunnel. It's a level of risk that I am prepared to take.

As to the sulphur products - from my understanding of the tunnel atmosphere the main reasons for the corrosion of metal components are the high humidity and the warmth. This document states:

A European Fuel Quality Directive was set out in 2009 which stated that as of 1st January 2011, all non-road mobile machinery should only contain up to a maximum of 10 milligrams of sulphur for every kilogram of fuel used (10 ppm or 0.001%). This made the use of fuel more ‘sulphur-free’ by reducing the levels by 99 percent and it also brought these sulphur levels in line with Ultra Low Sulphur Diesel (ULSD) EN590 for on-road use. The change to ‘sulphur free’ fuel was needed in order to comply with the latest EU non-road mobile machinery usage.

In 2010 an update was made in the UK to British Standard BS 2869 for gas oil (red diesel) requiring a limit of 10mg of sulphur per kg fuel for mobile off-road equipment. BS 2869 red diesel was split into two different categories. Class A2 covered all off-road vehicles, including trains and tractors. The sulphur content for class A2 diesel is 0.001% (10 ppm).

Half the length of the tunnel is downhill at about 1 in 100 and the line limit is 75mph so the trains' engines will be at 'flight idle'. More power will be needed for the climb out - but that still only amounts to about 2 minutes worth of exhaust. I can't see that the sulphur by-products produced by 10 parts per million of sulphur in the quantity of diesel used in two minutes would make much of a difference to corrosion rates to those already generated by the warm, salty and damp atmosphere.

 

[Fougasse]

Flash notice in this week’s WON stating equipment from the current limit of electrification at Patchway Junction to St Brides Feeder station (between Ebbw Junction and Marshfield) is to be considered live from 1100 hours on Saturday September 14th 2019.

General consensus among the worker bees is that 14 Sep (NR week 25) is a very ambitious target for energisation verging on overly optimistic (not quite the terms being used!).

 

[linuxlad7]

If one spent all day, every day in such an atmosphere it might have some effect on one's lungs - but the effect will vary from person to person.
The normal passenger train takes about 4 minutes to pass through the Severn Tunnel, and the passengers are in an enclosed tube so the levels of pollution will only build up over a period as the ventilation system draws in replacement air. After four minutes the ventilation system is drawing in clean air again.

For a commuter making a return trip by train every working day that is 8 minutes a day exposure to a level of pollution which is less than the level in the tunnel. It's a level of risk that I am prepared to take.

As to the sulphur products - from my understanding of the tunnel atmosphere the main reasons for the corrosion of metal components are the high humidity and the warmth. This document states:

Half the length of the tunnel is downhill at about 1 in 100 and the line limit is 75mph so the trains' engines will be at 'flight idle'. More power will be needed for the climb out - but that still only amounts to about 2 minutes worth of exhaust. I can't see that the sulphur by-products produced by 10 parts per million of sulphur in the quantity of diesel used in two minutes would make much of a difference to corrosion rates to those already generated by the warm, salty and damp atmosphere.

Er the Great Spring is fresh, not salt I think

 

[GRALISTAIR]

Heat accelerates any chemical reaction including corrosion. That is true. As for sulphur- I admitted without data I can’t prove it.

 

[kevin_roche]

Platform extensions ongoing at Slough

View attachment 67035 View attachment 67036 View attachment 67037

Just interested to know which direction these are happening in. Are the extensions at the western end of the platforms?

 

[Non Multi]

Just interested to know which direction these are happening in. Are the extensions at the western end of the platforms?

No, the eastern end beyond the new footbridge.

 

[kevin_roche]

No, the eastern end beyond the new footbridge.

Thank you. It is 20 years since I worked in Slough and I did not recognise the buildings in the pictures. Although I have been there since it wasn't by train and passing occasionally on a fast train to Reading doesn't give you time to see what's happening.

 

[MarlowDonkey]

No, the eastern end beyond the new footbridge.

There used to be a turnback line and bay platform facing London alongside platform 5, the Paddington direction Relief. There used to be an all stations service from Slough to Paddington. I suspect that went out of use when the Heathrow services started. In any event, it wouldn't have been usable for Crossrail because they stuck electrification masts in the way. To my mind it was a little odd that first Maidenhead and then Reading were chosen as the terminal stations for Crossrail rather than Slough.

 

[swt_passenger]

There used to be a turnback line and bay platform facing London alongside platform 5, the Paddington direction Relief. There used to be an all stations service from Slough to Paddington. I suspect that went out of use when the Heathrow services started. In any event, it wouldn't have been usable for Crossrail because they stuck electrification masts in the way. To my mind it was a little odd that first Maidenhead and then Reading were chosen as the terminal stations for Crossrail rather than Slough.

I expect Maidenhead was chosen because the track layout could be easily adapted so that Crossrail terminators could use a centrally located platform between up and down reliefs, and there was also a space for stabling sidings west of Maidenhead so that trains could enter and leave service there.

 

[hwl]

I expect Maidenhead was chosen because the track layout could be easily adapted so that Crossrail terminators could use a centrally located platform between up and down reliefs, and there was also a space for stabling sidings west of Maidenhead so that trains could enter and leave service there.

Closest sensible to Reading as they didn't want to be reliant on Reading rebuild/electrifcation or be asked for a contribution.

 

[reddragon]

Inevitably the IET diesel engines will be replaced by batteries on a number of units in 10 years so not really an issue

 

[cambsy]

If I travelled London-Wales week commencing 30th September will i be likely to have electric running all the way to Newport on all trains or will it be hit and miss? Will there be booked trains for electric running to Newport?.

 

[paul1609]

Inevitably the IET diesel engines will be replaced by batteries on a number of units in 10 years so not really an issue

I reckon there's no chance of that happening within 10 years and very little within 25

 

[coppercapped]

Heat accelerates any chemical reaction including corrosion. That is true. As for sulphur- I admitted without data I can’t prove it.

Sorry - I didn't mean to be so abrupt. I thought I would help the discussion along by finding out what the current levels are and in my enthusiasm failed to phrase my post properly.

Er the Great Spring is fresh, not salt I think

Oh yes, absolutely. But my understanding is that there are other, much smaller, sources of water ingress and some of these are salty. In addition both ends of the tunnel are not far from the sea so salty air can get carried in by the draught of the trains.

High humidity and slightly elevated temperatures can, as Gralistair says, accelerate corrosion rates.