Overshoot at St Austell?

Discussion in 'UK Railway Discussion' started by notadriver, 26 Aug 2015.

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  1. notadriver

    notadriver Established Member

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    Does anyone know anything about an alleged overshoot last night at St Austell?
     
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  3. Rich McLean

    Rich McLean Established Member

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    It happens, especially with the composite brake blocks now fitted to Mk3 stock combined with poor rail head conditions that we have had in this wet weather.

    Expect more of this sort of thing over the up and coming leaf fall season
     
  4. TDK

    TDK Established Member

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    Brake blocks are a lot better than disc brakes in leaf fall/low adhesion as they clean the wheels. The low adhesion recently has been minimal and to be fair an over run at this time of year is seldom diagnosed to be because of poor adhesion. You get a lot more brake fade with brake blocks than disc brakes and as a driver take this into account.
     
  5. jj1314

    jj1314 Member

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    Sorry to slightly change the topic, but might these new composite brakes be responsible for the slightly-strange odour not dissimilar to that of a burnt clutch plate I've noticed between Paddington and Didcot Parkway recently?
     
  6. VP185

    VP185 Member

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    Mk3's are not fitted with brake blocks, they utilise brake discs and pads.

    Brake fade is actually more a problem on disc braked trains especially at low speed than those fitted with blocks. The performance of disc braked trains varies greatly from train to train compared to those fitted with blocks.
     
  7. irish_rail

    irish_rail Established Member

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    WTF? "The low adheison recently has been minimal" Try talking to people who actually drive HSTs in the south west before coming out with bland statements like that. Since early summer (and especially the past month) adhesion has been very poor with the near constant rain.
    As Rich Mclean points out, new brake blocks have worsened the problem as the wheels are no longer getting "roughed up" , giving less grip.
    I have never known a summer like it for slippage (especially when under power), and am absolutely dreading the Autumn season.

    Thoughts to the driver concerned in this incident......:|
     
  8. HarleyDavidson

    HarleyDavidson Established Member

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    For me as a juice jockey, stopping doesn't appear to be an issue, it's the pulling away that causes issues, if you just sling a unit into full power, however the remedy is good old fashion hand notching if you're on a 455/456 or low power on a Desiro.
     
  9. Rich McLean

    Rich McLean Established Member

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    EDIT:

    Few things to clear up for clarity.

    MK3 trailers are disk braked with pads

    Power cars used to use cast iron break blocks. They now have composite break blocks which no longer rough up the powered wheels.This is where the issue is, and not from the Mk3 stock.

    Sorry for any confusion
     
    Last edited: 26 Aug 2015
  10. TEW

    TEW Established Member

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    I was on the train last night. It did happen, and the correct parties were immediately informed by the train crew and the protocols followed.
     
  11. VP185

    VP185 Member

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    Power cars actually use a combination of both disc brakes and tread brakes (brake blocks), it's not shared 50/50 between the two though.
     
  12. BestWestern

    BestWestern Established Member

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    That'll be the brakes, certainly, but it's nothing new. Under heavy braking HST trailers will always kick up a burning smell. Lets you know you've got a Driver who means business! <D
     
  13. TDK

    TDK Established Member

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    The statement is not bland it is fact maybe in the South West there has been adhesion problems but this is local, as I said it is very unusual that a train has an over run due to adhesion in August
    --- old post above --- --- new post below ---
    Tread brake trains have more fade from high speed than disc brakes trains by far, low speed you are correct however I have not had noticeable brake fade from the disc brakes traction I drive at any speed.
     
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