Deltic White line on tyres query

[Lost property]

Watched the move of a Deltic on "Train Truckers " and saw two white lines, the longer one appeared to be slightly offset, on the front tyres / wheels of the locomotive. On an aircraft wheel assy,these would be creep marks, but, I can't see this being the case here. Just curious, as always, given I've never noticed them before and would they be found on other types please ?

 

[GC class B1]

Watched the move of a Deltic on "Train Truckers " and saw two white lines, the longer one appeared to be slightly offset, on the front tyres / wheels of the locomotive. On an aircraft wheel assy,these would be creep marks, but, I can't see this being the case here. Just curious, as always, given I've never noticed them before and would they be found on other types please ?

I don’t know about Deltics specifically, but class 47 locomotives which have tyred wheelsets have three white lines painted on the outside of the wheels to indicate any movement of the tyres on the wheel centres. If the lines are offset this means that the tyre has moved. The white painted lines run from the tyre to the wheel centre radially and are painted at about 120° apart so that at least one line always visible.
It is quite possible that the Deltic was being moved by road because the tyres had moved.

 

[Lost property]

I don’t know about Deltics specifically, but class 47 locomotives which have tyred wheelsets have three white lines painted on the outside of the wheels to indicate any movement of the tyres on the wheel centres. If the lines are offset this means that the tyre has moved. The white painted lines run from the tyre to the wheel centre radially and are painted at about 120° apart so that at least one line always visible.
It is quite possible that the Deltic was being moved by road because the tyres had moved.

Thank you for the explanation...same principle as creep marks on inner tubed wheel assy's then although I have seen them on tubeless as well.

The Deltic was being moved by road after extensive maintenance for testing prior to release to service

 

[ac6000cw]

This is a Wikipedia page about railway tyres - https://en.wikipedia.org/wiki/Railway_tire

I assume that modern locos, MUs and hauled stock all have one-piece 'monoblock' wheels (no tyres) - is that correct?

 

[GC class B1]

Thank you for the explanation...same principle as creep marks on inner tubed wheel assy's then although I have seen them on tubeless as well.

The Deltic was being moved by road after extensive maintenance for testing prior to release to service

I am curious why you didn’t think the white lines wouldn’t be painted on the Deltic wheels for the same reason that they are on aircraft.
I also read from your post that on aircraft the rubber tyres may creep around the wheel centre in normal service. For tyred railway wheelsets, the interference fit is designed to prevent tyre movement unless the tyre becomes overheated as a result of a dragging brake and therefore movement is extremely rare but must the wheelsets must be checked and monitored if movement occurs.
I appreciate that rubber tyres are separate to the metal wheels and therefore able to move in the wheel centres. Tyred railway wheels are not as obvious as the join is not easily seen so I wouldn’t expect non railway people to know that tyres wheelsets existed. For your information tyred railway wheelsets are now quite rare as one reason they are not used for disc braked vehicles is because the braking as well as the traction forces are transmitted from the axle to the wheel tread and it is good engineering practice to minimise the number of interfaces.

 

[ac6000cw]

Did most of the 1960s diesel and electric locos have tyred wheelsets?
From the above Deltics and 47s obviously did, so I'd guess 20s and 37s did too. What about 24s-27s and 33s?

From what I've read in the past, as freight loco tractive efforts increased (with advances in wheelslip control), tyre slippage problems became more severe and drove the switch to one-piece wheels in that application.

 

[Lost property]

I am curious why you didn’t think the white lines wouldn’t be painted on the Deltic wheels for the same reason that they are on aircraft.
I also read from your post that on aircraft the rubber tyres may creep around the wheel centre in normal service. For tyred railway wheelsets, the interference fit is designed to prevent tyre movement unless the tyre becomes overheated as a result of a dragging brake and therefore movement is extremely rare but must the wheelsets must be checked and monitored if movement occurs.
I appreciate that rubber tyres are separate to the metal wheels and therefore able to move in the wheel centres. Tyred railway wheels are not as obvious as the join is not easily seen so I wouldn’t expect non railway people to know that tyres wheelsets existed. For your information tyred railway wheelsets are now quite rare as one reason they are not used for disc braked vehicles is because the braking as well as the traction forces are transmitted from the axle to the wheel tread and it is good engineering practice to minimise the number of interfaces.

Thanks for your detailed and informative reply.

To answer your question, as I said, creep marks on aircraft wheel assys are common, hence when I saw the marks on the Deltic wheel, I wondered if they were there for the same reason because I didn'trecall seeing them elsewhere.

I fully understand what an interference fit is and recall a programme showing the renovation and replacement of a tyre on a old locomotive at, Dartmouth ??...workshops and how little time once prepared there was to fit the tyre.

I also understand and appreciate the engineering principles in you last paragraph, thank you, and even more so because as you say, I'm a non railway person who happens to have a general interest in many aspects of rail operations. I am interested in many forms of transport in general terms and I think this is often the case with people who are involved with other transport sectors.

I always recognise and acknowledge people in other areas who pass on their knowledge because, as a non railway person, I encountered some very denigratory comments from some individuals or "an officer of the railway" as they like to be styled, as well as discrimination because I had no railway knowledge as such ...and could hold a conversation on topics other than trains on the railway I was familiar with.

 

[GC class B1]

Did most of the 1960s diesel and electric locos have tyred wheelsets?
From the above Deltics and 47s obviously did, so I'd guess 20s and 37s did too. What about 24s-27s and 33s?

From what I've read in the past, as freight loco tractive efforts increased (with advances in wheelslip control), tyre slippage problems became more severe and drove the switch to one-piece wheels in that application.

Yes from memory up until about 1970 tyred wheelsets were used on most if not all locomotives ( think the diesel hydraulic locos had monobloc wheels) and passenger vehicles. The class 86 passenger locomotives had them changed for a two piece wheel with rubber elements between the outer part of the wheel ( a complete disc) and a centre mounting piece fitted to the axle to reduce the unsprung mass and reduce track damage. All Disc braked vehicles including the Mk2 running on the Glasgow - Edinburgh push pull services had monobloc wheels. I think all new locomotives from class 56 and class 87 onwards had monobloc wheels but I am not sure about class 50. All second generation DMUs and EMus and most wagons have monobloc wheels.

== Doublepost prevention - post automatically merged: 15 Sep 2022 ==

Thanks for your detailed and informative reply.

To answer your question, as I said, creep marks on aircraft wheel assys are common, hence when I saw the marks on the Deltic wheel, I wondered if they were there for the same reason because I didn'trecall seeing them elsewhere.

I fully understand what an interference fit is and recall a programme showing the renovation and replacement of a tyre on a old locomotive at, Dartmouth ??...workshops and how little time once prepared there was to fit the tyre.

I also understand and appreciate the engineering principles in you last paragraph, thank you, and even more so because as you say, I'm a non railway person who happens to have a general interest in many aspects of rail operations. I am interested in many forms of transport in general terms and I think this is often the case with people who are involved with other transport sectors.

I always recognise and acknowledge people in other areas who pass on their knowledge because, as a non railway person, I encountered some very denigratory comments from some individuals or "an officer of the railway" as they like to be styled, as well as discrimination because I had no railway knowledge as such ...and could hold a conversation on topics other than trains on the railway I was familiar with.

I am disappointed and somewhat surprised that you have received derogatory remarks from people within the industry. One of the reasons that I found the railway industry enjoyable to work in is because of the width and breadth of expertise and disciplines within the industry and consequently the number of transferable skills. I am always keen to discuss my personal experiences in the industry with anyone who will listen and learn from others both within the industry and outside. I my opinion all of us in the industry are ambassadors and should always act as such. The railway industry is a public service and without the public the railways wouldn’t exist. On a personal note I always enjoy explaining those technical issues that I have knowledge about to those people who are interested to learn and in return I also learn from them.
The forum members are mix of professional railway people and enthusiastic non railway people and as such is an excellent mechanism for imparting and gaining knowledge (in my case in that order of priority). This is one of the reasons I joined this excellent forum.

 

[Lost property]

Yes from memory up until about 1970 tyred wheelsets were used on most if not all locomotives ( think the diesel hydraulic locos had monobloc wheels) and passenger vehicles. The class 86 passenger locomotives had them changed for a two piece wheel with rubber elements between the outer part of the wheel ( a complete disc) and a centre mounting piece fitted to the axle to reduce the unsprung mass and reduce track damage. All Disc braked vehicles including the Mk2 running on the Glasgow - Edinburgh push pull services had monobloc wheels. I think all new locomotives from class 56 and class 87 onwards had monobloc wheels but I am not sure about class 50. All second generation DMUs and EMus and most wagons have monobloc wheels.

== Doublepost prevention - post automatically merged: 15 Sep 2022 ==


I am disappointed and somewhat surprised that you have received derogatory remarks from people within the industry. One of the reasons that I found the railway industry enjoyable to work in is because of the width and breadth of expertise and disciplines within the industry and consequently the number of transferable skills. I am always keen to discuss my personal experiences in the industry with anyone who will listen and learn from others both within the industry and outside. I my opinion all of us in the industry are ambassadors and should always act as such. The railway industry is a public service and without the public the railways wouldn’t exist. On a personal note I always enjoy explaining those technical issues that I have knowledge about to those people who are interested to learn and in return I also learn from them.
The forum members are mix of professional railway people and enthusiastic non railway people and as such is an excellent mechanism for imparting and gaining knowledge (in my case in that order of priority). This is one of the reasons I joined this excellent forum.

Let me clarify please. It wasn't from mainline rail professionals I encountered....I once spent a very pleasant time talking with a driver about Skelton Jnc, as was, and is now...he was fascinated when I told him about the past layout...or indeed from most of the other volunteers...it came from a very small, but influential, group which does contain rail " professionals " and two, well three, individuals who felt they were beyond reproach .

I also enjoy this site for the same reasons as yourself, hence my acknowledgement to anybody who answers my queries.

 

[Dougal2345]

The class 86 passenger locomotives had them changed for a two piece wheel with rubber elements between the outer part of the wheel ( a complete disc) and a centre mounting piece fitted to the axle to reduce the unsprung mass and reduce track damage.

That's interesting - that's not in any way similar to the wheel design that caused the Eschede disaster in Germany?

 

[DarloRich]

Is it not so they know which way to tighten the wheel nuts?

 

[GC class B1]

That's interesting - that's not in any way similar to the wheel design that caused the Eschede disaster in Germany?

I think you may be right in principle and that the wheels involved in this incident had resilient elements that failed, but I suspect technically quite different to the class 86 SAB wheels.

 

[D6968]

Yes from memory up until about 1970 tyred wheelsets were used on most if not all locomotives ( think the diesel hydraulic locos had monobloc wheels) and passenger vehicles. The class 86 passenger locomotives had them changed for a two piece wheel with rubber elements between the outer part of the wheel ( a complete disc) and a centre mounting piece fitted to the axle to reduce the unsprung mass and reduce track damage. All Disc braked vehicles including the Mk2 running on the Glasgow - Edinburgh push pull services had monobloc wheels. I think all new locomotives from class 56 and class 87 onwards had monobloc wheels but I am not sure about class 50. All second generation DMUs and EMus and most wagons have monobloc wheels.

== Doublepost prevention - post automatically merged: 15 Sep 2022 ==


I am disappointed and somewhat surprised that you have received derogatory remarks from people within the industry. One of the reasons that I found the railway industry enjoyable to work in is because of the width and breadth of expertise and disciplines within the industry and consequently the number of transferable skills. I am always keen to discuss my personal experiences in the industry with anyone who will listen and learn from others both within the industry and outside. I my opinion all of us in the industry are ambassadors and should always act as such. The railway industry is a public service and without the public the railways wouldn’t exist. On a personal note I always enjoy explaining those technical issues that I have knowledge about to those people who are interested to learn and in return I also learn from them.
The forum members are mix of professional railway people and enthusiastic non railway people and as such is an excellent mechanism for imparting and gaining knowledge (in my case in that order of priority). This is one of the reasons I joined this excellent forum.

Err no, the hydraulics do not have monobloc wheels, I have a memory of a test on 821’s tyres slipping on its wheels from about 25 years ago.