A train with a wheelflat?

[truckman060473]

On Youtube "70002 on the Marches line" shows the coal hoppers coming through Ludlow at a low speed. At the end, the caption mentions a wheelflat on the rear wagon which is a prominent noise on the clip. Would a driver be aware of this, seeing as he's a few 100yds away in front? Who or what would inform him that there's a problem, and is it a high risk to run at speed in this condition?

 

[Wyvern]

One way is lineside equipment like the "Wheelchex" system or WILD - Wheel Impact Load Detector

 

[PaulW]

I've noticed on the Marches last year that quite a few of those hoppers had been scattered in sidings along the route due to this.

Usually signallers that notice these things unless they're locked up in PSBs!

 

[driver9000]

Vehicles can run with flats up a collective size of 60mm or a single flat of that size without restriction. If the flat is outside this then it's a maximum of 20mph to a location where it can be removed from the train.

Unless the driver heard it he wouldn't be aware of it. If you can hear it, it's ok, if you can feel it then it's time to stop.

 

[MggW]

The driver would not be aware. A wheelflat couldn't be heard from the front, and would not affect handling in any way.

Wheelchex and WILD will measure the force being exerted by the flat, and the severity of that will determine what speed a train can continue at, if at all.

 

[9K43]

A wheel flat is caused by leaving a hand brake on and dragging the truck along the track etc.
An air brake which has been over charged, which applies the brake.
A bad flat will cause scaling to the wheel set, causing massive heat to be generated, effecting the wheel bearing.
Before any goods train leaves a siding, it must be prepared and passed fit to travel by a competent person, passed out in the duties of examining vehicles.
Part of this inspection is to perform a roll by, where the train is drawn past the Shunter/tapper at a slow speed. This inspection is to check if wheel flats are on any trucks, or hand brakes applied or rubbing on the tyres, or any other defect that may effect the safe running of that train.
You can detect a problems with a wheel flat by the noise it makes when moving.
If it has seized the wheel bearing, the wheel will smell of boiling grease in that bearing or the heat coming from the afflicted wheel set.
If it is only a small flat on the tyre, it will wear itself out in traffic.
If on inspection the the tyre has scale all over it, it comes out of the train.
Then a Red Card marked NOT TO GO will be placed on the clips of the truck.
If you have a bad wheel flat on the main line, the driver maybe far away from the defective truck.
Anyone on or about the line should watch trains go by to watch out for defects on the passing train, and report ir ASP to the signal box.
If the wheel defect is really bad, the Knottigley Team would bring out a wheel set and change it in situ, or get it on a wheel skate to repair at at KY Depot.
It is a hanging offence to let a truck/vehicle into traffic with a defective wheel or hand brake pinned down.
On the main lines there are Hot Box Axle Detectors linked into the Signal Box.
If one these detectors is actioned, the signal box will stop the train, and the driver will have to inspect the train and report back.

 

[Wyvern]

Just to be clear a hot box detector (HABD) is different from a wheel flat detector (WILD)

The former (I believe) detects radiated heat from the bearing, while the latter measures mechanical vibration produced in the rail, mainly from a tread flat. The more sophisticated can also recognise vibration caused by a dragging brake or disintegrated or siezing bearing.

Hot Box & Hot Wheel Detectors

 

[9K43]

Just to be clear a hot box detector (HABD) is different from a wheel flat detector (WILD)

The former (I believe) detects radiated heat from the bearing, while the latter measures mechanical vibration produced in the rail, mainly from a tread flat. The more sophisticated can also recognise vibration caused by a dragging brake or disintegrated or siezing bearing.

Hot Box & Hot Wheel Detectors[/QUO

No offence, but with a hot box activation its normal a false alarm.
Smell, sound, sight and touch is the best way of finding a hot box.
You can save all your machines, I can detect a hot box upwind 20 trucks by the smell of hot oil/grease, a bit closer the crackeling of the effected bearing, then the touch of the bearing cap and I see the smoke/fire from the effected bearing.
If train preperation is carried out properly, you can eliminate hot boxes/bearings on trains.
EWS would shoot you out of hand if a train was let out onto the main line with a hand brake pinned down.

 

[Wyvern]

Didnt they use to use aniseed in the bearings at one time?

Wasn't there also a heat detecting wax stick?

 

[StoneRoad]

My local line has multiple unit trains of various classes, and it is not unknown for a set to have a bad wheel flat. Reporting it to staff seems to be ignored, as quite a while ago, the same unit, with the same flat on the rearmost bogie, stayed in traffic for several days. I know that I was not the only person to report the fault! (unfortunately I no longer have the service and vehicle details available)

 

[driver9000]

My local line has multiple unit trains of various classes, and it is not unknown for a set to have a bad wheel flat. Reporting it to staff seems to be ignored, as quite a while ago, the same unit, with the same flat on the rearmost bogie, stayed in traffic for several days. I know that I was not the only person to report the fault! (unfortunately I no longer have the service and vehicle details available)

It was probably already entered in the repair book and noted as 'within tolerance FHDA'. I've known them stay in traffic for weeks with flats before eventually being sent for tyre turning.

FHDA - For Home Depot Attention.

 

[9K43]

Didnt they use to use aniseed in the bearings at one time?

Wasn't there also a heat detecting wax stick?

When Mallard broke the World Speed Record, the engine was taken off after the run, as the middle big end was running hot.
When oiling round, the oil when it got hot, smelled of garlick.
Driver Duddington of Donny shed knew the bigend had gone as he could smell the scent of garlick.
This was a common defect with the A4's.

When coming back from York one Friday Night on a loose coupled train, I got the wiff of hot oil back in the Brake Van.
When we go to Castleford, I threw the Bobby a Red one, and he stopped the train as Castleford Gates.
I got out of the brake and examined the train, I found a wheel running hot on an old bogie bolster.
As we had about 10 miles to go to the Mill, we ran at very much reduced speed and got back with no problems.
The Driver on this job was Danny Kaye( Johnny opposite.)
The stick you are talking about was the ' Temple Stick. '
Smell, touch, and see is the best detector of a hot box.

The link below is my stamp for examing trains. This must stamped on tops sheets and drivers slips before that train goes on the mainline. ( I have edited my name out of the stamp.)

http://www.imagebam.com/image/f799d096284708

 

[gregh]

Smell, touch, and pee too

Pee on it, and if it turns to steam, it's flippin' hot

 

[9K43]

Smell, touch, and pee too

Pee on it, and if it turns to steam, it's flippin' hot

I forgot to mention pee as its rather rude.
If a wheel set was far gone, it was just a jesture if you peed on the set.
That would be like chucking a bucket of water on a raging forrest fire.
If it made you fell good then why not.

 

[gregh]

I'd rather pee on it than touch it, i know that. Better a cloud of steam than a singed middle finger.
--- old post above --- --- new post below ---

An air brake which has been over charged, which applies the brake.

Over-charging an air brake system will have exactly the opposite effect, i.e. to release the brake.

Over-charging an air brake system is a procedure carried out after a brake continuity test has been completed. Standard running pressure for the train air brake pipe is 5 bar, or 72.5 psi. Overcharging the system puts an extra 0.5 bar into the system to ensure that any possible brake drag after a complete venting of the system is eliminated. This extra 0.5 bar is allowed to gently bleed off over a period of several minutes, thus returning the brake pipe to standard running pressure but without the danger of creating brake drag. On older locomotives, the overcharge facility was built into the train brake handle in the cab. On modern locomotives it generally takes the form of a push button on the desk.

As regards hot boxes - we still all carry Templesticks. They really are the best way of determining whether a bearing is failing or not. Hot Axle Box Detectors are also pretty good at picking them up, and as the technology has improved over the years we now get far fewer false alarms whereby the HABD has picked up brake pad heat rather than a failing bearing, and caused the signalman to pull us up.

 

[9K43]

I hear what you say about dragging brakes.
Many times I have had to go round trains that have been over charged, and pull the strings on the vehicles.
3 examples were continetal ferry vans coming out of COBRA, at Wakefield, with 1 van sliding on the rails.
2 A passenger charter train with a Deltic on the front came to a stop out side of Flasgrave Box , with dragging brakes, remedy go round the train and pull the strings.
A train of 30 HEA wagons from NCB loading plant at Gasgoin Wood, Selby. ( Now demolished. )
The NCB Pilot overcharged the brakes and it brought us to a stop, yet again go round 30 wagons and pull the strings..
It does not take a fully loaded truck long to wear a flat into the wheel sets when the brakes are dragging.
You only have to sit over a bogie on and HST to hear the drumming of the numerous flats on the wheels.
Then the Freight Companies are after some ones scalp for sending a defective train onto the system.