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Any idea about this pattern on the top of the rail?
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RailUK Forums
Looks like an example of rolling contact fatigue (see this article). However, I'm not entirely certain if that is the case, and I'm sure there must be at least one permanent way engineer on this forum somewhere who will put me right if I am wrong.
BTW, where was this taken? It doesn't look British.
BTW, where was this taken? It doesn't look British.
Wyvern
Established Member
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Has the rail grinder been past a little while ago?
Old Timer
Established Member
Rolling Contact Fatigue (RCF).
Looks like hardened US rail on a heavy haul site ?
Looks like hardened US rail on a heavy haul site ?
asylumxl
Established Member
It would seem the OP is in America judging by him using METRA for his daily commute 
. I may be totally wrong.
. I may be totally wrong.
I assumed it wouldn't be bad, but yeah it was taken in the Chicago suburbs on the Union Pacific line. This track has a 70 mph limit.
Probably the rail grinder is a good theory since I hadn't noticed it before.
I'm an ex-pat so hence why I hang out with you guys
Probably the rail grinder is a good theory since I hadn't noticed it before.
I'm an ex-pat so hence why I hang out with you guys
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I was thinking a rail grinder - but as said the picture didn't look English so left it and saw what came up.
(Admin/Mods)Maybe this is worth moving to the International Rail Area
(Admin/Mods)Maybe this is worth moving to the International Rail Area
hock:
TheExmoorBeast
Member
Good job you never saw the track at Wimbledon on the down fast a couple of years ago, it started bouncing when a train got to the Waterloo end of the platform with mud geysers all over the place. Linespeed 75mph.
It seems NR have been working hard down here and apart from one or two locations where it seems a bit lively, the track's in pretty good nick.
It seems NR have been working hard down here and apart from one or two locations where it seems a bit lively, the track's in pretty good nick.
thefab444
Established Member
Living in Taunton I didn't know you'd have much experience of Wimbledon's trackwork?
Interesting nonetheless, and good to hear NR are sorting it out.
Interesting nonetheless, and good to hear NR are sorting it out.
TheExmoorBeast
Member
I don't normally, however I was on the platform waiting for a train back to Surbiton for the connection into the Woking/Basingstoke train and watching it with some interest. Quite shocking.
Old Timer
Established Member
No grinder has been anywhere near there.
Perhaps not a hand grinder but I remember a couple of years ago that a rail grinding train was working on the line where I was working and left marks identical to the OP's picture.
After a couple of months of general use the marks were gone and the rail head was back to normal.
Old Timer
Established Member
Not a grinding train either. The purpose of grinding is to remove the headchecking.
The headchecking here extends across the top of the rail, through the wear band which can be seen in the centre of the rail.
The location being N. America, I anticipate they will be using the LORAM GR1 which takes the rail head down to good steel.
b0b
Is this rail in the braking curve, towards a signal or junction perhaps ?
Trog
Established Member
It looks like rail grinding to me, run on enough to have got back nearly to smooth along the crown of the rail.
Old Timer
Established Member
If you look closer you will see the marks run across the rail, the picture is slightly over-exposed on the wear band giving that impression.
There are also no grinding marks on the head corners, because the Americans take the grind right across the head.
It's at a station - I got off the train and noticed the pattern and wondered what caused it as I'd never seen anything other than a shiny rail on regularly used track. It's also in the breaking curve for a signal where three tracks go down to two - UP freight trains regularly wait at this station waiting for a gap in commuter service to get a path.
Is there a particular reason you asked that?
Trog
Established Member
b0b
Is there any sign of rusty staining on the track as if iron fileings had been scattered about? Or even lumps of 'metal' where the iron fileings that collect on the spark guards have dropped off a grinding train. These lumps are usually part circular in shape, and a mixture of blue and rust coloured depending on how long they have been laying out in the weather.
Is there any sign of rusty staining on the track as if iron fileings had been scattered about? Or even lumps of 'metal' where the iron fileings that collect on the spark guards have dropped off a grinding train. These lumps are usually part circular in shape, and a mixture of blue and rust coloured depending on how long they have been laying out in the weather.
chuffchuff
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I'm with Old Timer on this
No grinder has been near it
Another couple of years and the top will have waves on it
No grinder has been near it
Another couple of years and the top will have waves on it
Can someone then explain what I witnessed? Ie, clean rail head, rail grinding train came through which after resulted in the rail head looking exactly the same as the picture in the orginal post...for quite some miles.
After some use (about 2 or 3 months) the marks on the rail head were gone and looked the same as any other piece of rail.
After some use (about 2 or 3 months) the marks on the rail head were gone and looked the same as any other piece of rail.
Old Timer
Established Member
The original poster stated that the picture was over-exposed thus explaining the bright band on the head of the rail.
I have seen RCF of exactly this nature in the Americas before, where the top of the rail is well worn but with RCF marks on the gauge side of the rail.
I am trying to ,locate a picture with this type of RCF pattern.
It is particularly prevelant on heavy-haul freight railways and seems to be related to a particular strength of steel in that scenario. There are trials with a different steel ongoing to see if this is the case. Early experience suggests this is so.
The photo was taken in the US where the practice is to grind the whole running surface of the rail and the gauge corner, in order to restore the original profile of the rail. This grinding will go down into the RCF and remove it. The result is a clean rail head. A visit to the Loram website will find a video illustrating this.
In the picture there has been no reprofiling of the gauge corner which will allow the RCF to continue to propogate. That alone to me suggests no grinding.
This one has what appears to be the wear band with RCF still present and does suggest that it has not been ground. Tie this in with the original words and the wear band should not be as bright as it is.
If the original poster can supply a better exposed picture or can confirm the presence of any markings that suggests rail grinding HAS taken place, as asked by Trog then I am happy to look at it again and revise my comment. As far as I can see though, there is no obvious evidence of dust or contamination on the sleepers or the baseplates. That said, the US systems now do remove much of this during the grinding process.
If the photo has been taken in the UK then I would tend to go with Trog who is a very experienced Engineer and much respected by myself. Bearing in mind the fact that this is not in the UK I hold a different view. That does not suggest he is wrong, simply it is indicative of our different practices and experiences. I have never been involved in maintenance in the UK.
b0b
The reason for asking was to confirm that the head checking is due to the braking forces from the trains. Normally I would expect to see RCF primarily (but not always) predominantly on the outside rail where a curve is involved. In the US they do not apply cant in the vast majority of Railroads unlike European practice. The type of RCF in the photograph gave every indication of head checking through traction braking forces, and your reply supports the belief that this is the means by which it is propogated. I have a case of some 900 miles of track where this problem is evident but only through S&C
I have seen RCF of exactly this nature in the Americas before, where the top of the rail is well worn but with RCF marks on the gauge side of the rail.
I am trying to ,locate a picture with this type of RCF pattern.
It is particularly prevelant on heavy-haul freight railways and seems to be related to a particular strength of steel in that scenario. There are trials with a different steel ongoing to see if this is the case. Early experience suggests this is so.
The photo was taken in the US where the practice is to grind the whole running surface of the rail and the gauge corner, in order to restore the original profile of the rail. This grinding will go down into the RCF and remove it. The result is a clean rail head. A visit to the Loram website will find a video illustrating this.
In the picture there has been no reprofiling of the gauge corner which will allow the RCF to continue to propogate. That alone to me suggests no grinding.
This one has what appears to be the wear band with RCF still present and does suggest that it has not been ground. Tie this in with the original words and the wear band should not be as bright as it is.
If the original poster can supply a better exposed picture or can confirm the presence of any markings that suggests rail grinding HAS taken place, as asked by Trog then I am happy to look at it again and revise my comment. As far as I can see though, there is no obvious evidence of dust or contamination on the sleepers or the baseplates. That said, the US systems now do remove much of this during the grinding process.
If the photo has been taken in the UK then I would tend to go with Trog who is a very experienced Engineer and much respected by myself. Bearing in mind the fact that this is not in the UK I hold a different view. That does not suggest he is wrong, simply it is indicative of our different practices and experiences. I have never been involved in maintenance in the UK.
b0b
The reason for asking was to confirm that the head checking is due to the braking forces from the trains. Normally I would expect to see RCF primarily (but not always) predominantly on the outside rail where a curve is involved. In the US they do not apply cant in the vast majority of Railroads unlike European practice. The type of RCF in the photograph gave every indication of head checking through traction braking forces, and your reply supports the belief that this is the means by which it is propogated. I have a case of some 900 miles of track where this problem is evident but only through S&C
Trog
Established Member
While my opinion has to be viewed in the light of me never having been on track west of Swansea. While Old Timer has I believe been out to the USA and scrunched their ballast.
The thing that really makes me think that this is the marks left by a grinding train is the repartition of some of the more prominent marks. I have marked up two series of them on the original photo. Note how they both repeat at the same spacing, and stay in step.
This says to me that this is the direct result of a one off mechanical process. While RCF is also repetitive, I would expect a much more 'analogue' feel to the markings as their spacing was affected by variations in the rail steel and small differences in the top and line.
The thing that really makes me think that this is the marks left by a grinding train is the repartition of some of the more prominent marks. I have marked up two series of them on the original photo. Note how they both repeat at the same spacing, and stay in step.
This says to me that this is the direct result of a one off mechanical process. While RCF is also repetitive, I would expect a much more 'analogue' feel to the markings as their spacing was affected by variations in the rail steel and small differences in the top and line.
Old Timer
Established Member
Trog
An interesting analysis, and well presented. Your points certainly merit further investigation.
b0b
Is it possible to get any more pictures, specifically those metered/focussed onto the railhead itself ?
Also can you confirm the RR who maintains the track ?
If you can, could you check the inside (gauge side of the railhead) and get a photo of that ? If not can you see any evidence of grinding to the inside top of the rail just below the head ?
If you can get to the S&C could you get a few photos of the rails within the S&C ?
GB
Consider this one still open, whilst we see what other photos we dig up ? Trog has made some good points which I would like to explore if possible before we put this one to bed.
An interesting analysis, and well presented. Your points certainly merit further investigation.
b0b
Is it possible to get any more pictures, specifically those metered/focussed onto the railhead itself ?
Also can you confirm the RR who maintains the track ?
If you can, could you check the inside (gauge side of the railhead) and get a photo of that ? If not can you see any evidence of grinding to the inside top of the rail just below the head ?
If you can get to the S&C could you get a few photos of the rails within the S&C ?
GB
Consider this one still open, whilst we see what other photos we dig up ? Trog has made some good points which I would like to explore if possible before we put this one to bed.
I'll take my DSLR camera to work on Monday and take a good picture for everybody.
This is track maintained by Union Pacific, specifically Union Pacific's ex-Chicago & North Western West Line to Omaha.
I did take a look at the track last Thursday while looking for the shavings and the wear band is starting to come back though, so I hope I'm not too late. I didn't see anything that looked like shavings, but some of the sleepers where coated in some sort of blue metallic substance - though this being a line with heavy freight traffic, it is not unusual to see deposits like that.
This is track maintained by Union Pacific, specifically Union Pacific's ex-Chicago & North Western West Line to Omaha.
I did take a look at the track last Thursday while looking for the shavings and the wear band is starting to come back though, so I hope I'm not too late. I didn't see anything that looked like shavings, but some of the sleepers where coated in some sort of blue metallic substance - though this being a line with heavy freight traffic, it is not unusual to see deposits like that.
Trog
Established Member
b0b think of big corse grinding stones being used, what you are looking for or the absence of. Is the traces of the burning fileings that come off the stones. You may also see lumps of this material that have collected then dropped off the guards that contain the sparks. Particually any where that the machine may have had to stop or start work.
The rails and baseplates are also sometimes stained, in a way that changes their colour in a way that makes them look newer. The fresh rust of the grinding debri, being darker than the weathered rust surface on an old rail.
You may also if there has not been too much traffic since the grinding has been done, see that the curve of the rail head is made up of several facets. Where a group of flat stones, all at slightly different angles has been used to restore the curve of the rail head.
The aim of restoring the head profile is to get the wheels to run along the top of the rail. So that the contact forces between wheel and rail are spread out, and not concentrated on the gauge corner of the rail. So if the wheels appear to be running mainly on the top centre of the rail, rather than right across and onto the gauge face. This to could be evidence that the rail has been ground.
The rails and baseplates are also sometimes stained, in a way that changes their colour in a way that makes them look newer. The fresh rust of the grinding debri, being darker than the weathered rust surface on an old rail.
You may also if there has not been too much traffic since the grinding has been done, see that the curve of the rail head is made up of several facets. Where a group of flat stones, all at slightly different angles has been used to restore the curve of the rail head.
The aim of restoring the head profile is to get the wheels to run along the top of the rail. So that the contact forces between wheel and rail are spread out, and not concentrated on the gauge corner of the rail. So if the wheels appear to be running mainly on the top centre of the rail, rather than right across and onto the gauge face. This to could be evidence that the rail has been ground.
The line is considered to be over capacity and UP is currently extending the triple track west of the station where the triple track currently ends for several miles.
Checking the timetable, there are 30 booked passenger trains per weekday (in each direction), plus virtually constant freight when there are paths between the passenger service. There's a joke around here with freight trains that it takes "2 days to get to chicago and 2 days to get through".
So maybe it's not the southern end of the WCML where pendos fly through every 10 mins but its certainly a line that sees traffic.
--- old post above --- --- new post below ---
Little later than planned but some pics with my DSLR:
http://www.midml.com/~bob/rail/DSC_7513.JPG - close up of the rail
http://www.midml.com/~bob/rail/DSC_7514.JPG
http://www.midml.com/~bob/rail/DSC_7515.JPG - this is the rail on the other side, so you can see the "inside" of the rail. I was too scared to get down on the track on the other side to take the inside picture
http://www.midml.com/~bob/rail/DSC_7516.JPG - slightly further east of the other pictures, i saw these marking on the top & side of rail
http://www.midml.com/~bob/rail/DSC_7518.JPG
http://www.midml.com/~bob/rail/DSC_7519.JPG - the metallic blue substance I saw on the sleepers. maybe related or not?
I'm still with the grinding theory, the marks Trog pointed out are so obvious along the running rail that they had to be put there deliberately. also there are similar markings on the other side...
hope you have fun with this little part of US rail
Checking the timetable, there are 30 booked passenger trains per weekday (in each direction), plus virtually constant freight when there are paths between the passenger service. There's a joke around here with freight trains that it takes "2 days to get to chicago and 2 days to get through".
So maybe it's not the southern end of the WCML where pendos fly through every 10 mins but its certainly a line that sees traffic.
--- old post above --- --- new post below ---
Little later than planned but some pics with my DSLR:
http://www.midml.com/~bob/rail/DSC_7513.JPG - close up of the rail
http://www.midml.com/~bob/rail/DSC_7514.JPG
http://www.midml.com/~bob/rail/DSC_7515.JPG - this is the rail on the other side, so you can see the "inside" of the rail. I was too scared to get down on the track on the other side to take the inside picture
http://www.midml.com/~bob/rail/DSC_7516.JPG - slightly further east of the other pictures, i saw these marking on the top & side of rail
http://www.midml.com/~bob/rail/DSC_7518.JPG
http://www.midml.com/~bob/rail/DSC_7519.JPG - the metallic blue substance I saw on the sleepers. maybe related or not?
I'm still with the grinding theory, the marks Trog pointed out are so obvious along the running rail that they had to be put there deliberately. also there are similar markings on the other side...
hope you have fun with this little part of US rail
Old Timer
Established Member
b0b
Thank you for the detailed photos. They are much better and have more detail.
I agree with Trog that there has been rail grinding taking place. Photo 7514 shows steel particles on the web and foot of the rail. You can also see the gauge corner grinding, as I do not think the rail is on a curve and the surface is vertical rather than worn.
The rail head marks are also in opposition.
Thank you for the detailed photos. They are much better and have more detail.
I agree with Trog that there has been rail grinding taking place. Photo 7514 shows steel particles on the web and foot of the rail. You can also see the gauge corner grinding, as I do not think the rail is on a curve and the surface is vertical rather than worn.
The rail head marks are also in opposition.
Trog
Established Member
The marks on the side of the rail in 7516 photo look to just be tar or oil. But I really don't like the look of the mark running along the head of the rail, in the middle of the photo.
That looks as if it could be a longitudinal split in the rail, perhaps caused by problems when the rail was rolled. The warning sign with a defect like that is that as it starts to fail the head of the rail tends to sink and spread so you get a wide patch in the shiny running path on the rail, like a squat defect but longer. The grinding will however tend to hide that, at least for a while by restoring the rail head shape back towards its normal shape.
--- old post above --- --- new post below ---
It used to be a standard but not very widely used maintenance activity, targeted on rails that were developing surface corrogations. Sometimes called roaring rails due to the noise they made when a train ran over them.
It was stopped in the early Railtrack period as a money saver.
But now it is a regular planned process to help prevent the spread of RCF cracks.
That looks as if it could be a longitudinal split in the rail, perhaps caused by problems when the rail was rolled. The warning sign with a defect like that is that as it starts to fail the head of the rail tends to sink and spread so you get a wide patch in the shiny running path on the rail, like a squat defect but longer. The grinding will however tend to hide that, at least for a while by restoring the rail head shape back towards its normal shape.
--- old post above --- --- new post below ---
It used to be a standard but not very widely used maintenance activity, targeted on rails that were developing surface corrogations. Sometimes called roaring rails due to the noise they made when a train ran over them.
It was stopped in the early Railtrack period as a money saver.
But now it is a regular planned process to help prevent the spread of RCF cracks.
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