What Are Wheel Flats?

[Highlandspring]

Flats always sound much worse than they actually are. Many people won’t have heard the cacophony from a seriously damaged wheel but you’re left in no doubt about it when one does pass you. As a matter of interest I’ve previously been told by a rolling stock engineer that very small flats tend to “run themselves out” as the tyre wears and don’t necessarily need to go on the lathe. Does anyone know if that’s true?

 

[Erniescooper]

Flats always sound much worse than they actually are. Many people won’t have heard the cacophony from a seriously damaged wheel but you’re left in no doubt about it when one does pass you. As a matter of interest I’ve previously been told by a rolling stock engineer that very small flats tend to “run themselves out” as the tyre wears and don’t necessarily need to go on the lathe. Does anyone know if that’s true?

On stock with tread brakes you stand a chance they may run out but with disc brake stock you nearly always end up turning the flats out however small they are.

 

[Erniescooper]

I have twittered the TOC to tell them about bad wheel flats. I have told the guard when i got off about flats in the front carriage of a unit. Cant hurt to speak up.

What tends to happen is that unless the flat is on the bogie directly under the cab and it starts to irritate the driver then they are just ignored and then after a few days the flat starts to form a cavity and next thing you know you have a Gotcha activation of 300 Kn .
If anybody feels like a read this https://www.rssb.co.uk/rgs/standards/GMGN2497 Iss 1.pdf is pretty much the bible of wheel set maintenance.

 

[37057]

What tends to happen is that unless the flat is on the bogie directly under the cab and it starts to irritate the driver then they are just ignored and then after a few days the flat starts to form a cavity and next thing you know you have a Gotcha activation of 300 Kn .
If anybody feels like a read this https://www.rssb.co.uk/rgs/standards/GMGN2497 Iss 1.pdf is pretty much the bible of wheel set maintenance.

When maintenance control can hear the flats over the phone you know they're bad. Rode a unit once for flats and an old lady got up to show me where they were. Doesn't make you popular after inspecting them at a station when it's announced that the train has to be taken out of service. Especially when it's the crew's train home and it's reduce speed!

 

[Highlandspring]

after a few days the flat starts to form a cavity and next thing you know you have a Gotcha activation of 300 Kn .

494kN is the biggest Gotcha activation I’ve dealt with. You could probably hear it faintly from on the moon.

 

[Railengineer]

Great Western have always been reactive in their approach to wheelflats and maintenance in general. The likes of East Coast, MML and Grand Central all fitted new Westinghouse/Knorr-Bremse wheelslide protection systems to their coaches and power cars (power cars got them with the upgraded Brush electronics package, as well as improved Wheelslip control systems). LNER and EMT (and GC when they had HSTs) also operate a policy of doing preventative tyre turning which skims the wheels to remove tread damage before bigger problems develop and a much bigger chunk of wheel needs to be removed on the lathe. As a result passengers get a better ride - it is rare to find a wheelflat on an EMT HST even during the leaf fall season, for example - and the operator can get extended wheelset life. As a result those operators have extended time between power car bogie overhauls out to at least 588,000 miles and in some cases 630,000 miles. Meanwhile GWR - who have never done the power car upgrades and have been haphazard with the trailers - are still at 480,000 miles between power car bogie changes and routinely run vehicles with severe flats.

Remember - There is nothing 'Great' about Great Western.
The reason they are reactive is because the owning group dos not care about the customer. Money is First

 

[43096]

Remember - There is nothing 'Great' about Great Western.
The reason they are reactive is because the owning group dos not care about the customer. Money is First

Ironically that approach has lead to them not paying a dividend to shareholders for around five years. Even better they promoted the CFO who has overseen that to CEO last year!

 

[trainmania100]

I remember as a kid standing near the line at Cullompton hearing huge bangs as GW HSTs went past. Clearly no one was that bothered in the late 90s early 00s about getting stuff reprofiled!

I cannot go to Devon without stopping at cullompton service station and seeing the trains

 

[edwin_m]

I remember as a kid standing near the line at Cullompton hearing huge bangs as GW HSTs went past. Clearly no one was that bothered in the late 90s early 00s about getting stuff reprofiled!

Was a crackdown on wheelflats part of Railtrack's response to the gauge corner cracking issue? I don't recall but I think Wheelchex first came in around that time.