If you register, you can do a lot more. And become an active part of our growing community. You'll have access to hidden forums, and enjoy the ability of replying and starting conversations.

P2 Locomotive Company and related matters

Discussion in 'Steam Traction' started by class8mikado, Sep 13, 2013.

  1. The Green Howards

    The Green Howards Part of the furniture

    Joined:
    Feb 20, 2016
    Messages:
    2,831
    Likes Received:
    963
    Occupation:
    Layabout
    Location:
    Your nightmares
    Heritage Railway Volunteer:
    No I do not currently volunteer
    Aww, shucks.... looks like I'm going to end up being a covenantor to the P2 as well as Tornado now!
     
    Foxhunter likes this.
  2. Eightpot

    Eightpot Part of the furniture

    Joined:
    Aug 10, 2006
    Messages:
    5,035
    Likes Received:
    577
    Location:
    Aylesbury
    Are the cylinder bores smaller than the originals to reduce the overall width, or to spread out the piston rod centres a little?
     
  3. Foxhunter

    Foxhunter Member

    Joined:
    Jun 9, 2011
    Messages:
    493
    Likes Received:
    257
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    With the increased boiler pressure (compared to the original class) the opportunity has been taken to fit smaller cylinders so that No. 2007 isn't as 'wide about the hips' as the early P2s - this means it will conform better with NR's loading gauge.

    Foxy
     
  4. Eightpot

    Eightpot Part of the furniture

    Joined:
    Aug 10, 2006
    Messages:
    5,035
    Likes Received:
    577
    Location:
    Aylesbury
    Thanks for that info. 2001 was 8' - 11-1/4" over the cylinders, which is 1-3/8" more than an A3 at 8' - 9-7/8". However, with the P2 cylinders immediately in front of driving/coupled wheels rather than further forward between the sets of bogie wheels wouldn't the P2 have less 'throw-over' of the cylinders on curves compared with an A3?
     
  5. Foxhunter

    Foxhunter Member

    Joined:
    Jun 9, 2011
    Messages:
    493
    Likes Received:
    257
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    ....meanwhile, in darkest Devon, the pace is being cranked up.... see the news here.

    [​IMG]

    Foxy
     
  6. Hermod

    Hermod New Member

    Joined:
    May 6, 2017
    Messages:
    69
    Likes Received:
    10
    Gender:
    Male
    Location:
    Klitmoeller,Denmark
    Heritage Railway Volunteer:
    No I do not currently volunteer
    Last edited: Jun 8, 2017
  7. Matt37401

    Matt37401 Part of the furniture

    Joined:
    Jun 8, 2014
    Messages:
    5,033
    Likes Received:
    1,313
    Gender:
    Male
    Location:
    31A
    Heritage Railway Volunteer:
    No I do not currently volunteer
    That looks a seriously big chunk of metal!
     
  8. Steve

    Steve Resident of Nat Pres Friend

    Joined:
    Oct 7, 2006
    Messages:
    7,693
    Likes Received:
    1,782
    Occupation:
    Gentleman of leisure, nowadays
    Location:
    Near Leeds
    Heritage Railway Volunteer:
    Yes I am an active volunteer
  9. S.A.C. Martin

    S.A.C. Martin Well-Known Member

    Joined:
    Aug 31, 2010
    Messages:
    1,928
    Likes Received:
    1,004
    Gender:
    Male
    Occupation:
    Compliance Control Officer, Writer & Film Maker
    Location:
    Sidcup, Kent
    Heritage Railway Volunteer:
    No I do not currently volunteer
    Epic! Looks brilliant boys. Keep it up!
     
  10. Hermod

    Hermod New Member

    Joined:
    May 6, 2017
    Messages:
    69
    Likes Received:
    10
    Gender:
    Male
    Location:
    Klitmoeller,Denmark
    Heritage Railway Volunteer:
    No I do not currently volunteer
    Was it some kind of poppet valve with rotary cams on P2?
    The forged ones can be stronger?P2s had crank issues.
     
  11. W.Williams

    W.Williams Member

    Joined:
    Dec 20, 2015
    Messages:
    347
    Likes Received:
    179
    Occupation:
    Mechanical Engineer
    Location:
    Aberdeen
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    This was pressed? with heat right?

    Forging is great if you have the equipment, but a fabricated assy can be equally as well engineered.
     
    Sunnieboy likes this.
  12. Foxhunter

    Foxhunter Member

    Joined:
    Jun 9, 2011
    Messages:
    493
    Likes Received:
    257
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    A critical failure area on the original class P2s was the crank axle. Modern principles are being adopted in the redesign of this critical area. Larger diameter components and the use of roller bearings are considered beneficial, and more modern techniques avoid stress points and relieve fatigue points. To this end the stubs are the largest that can be fitted with roller bearings and have stress relief grooves cut into them - clearly visible in the images.

    Foxy
     
  13. W.Williams

    W.Williams Member

    Joined:
    Dec 20, 2015
    Messages:
    347
    Likes Received:
    179
    Occupation:
    Mechanical Engineer
    Location:
    Aberdeen
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    Have material grades helped too? Specifically that we have tougher grades nowadays.
     
  14. Eightpot

    Eightpot Part of the furniture

    Joined:
    Aug 10, 2006
    Messages:
    5,035
    Likes Received:
    577
    Location:
    Aylesbury
    To answer your question 1) it is driven by a mini cranked axle on the middle (outside) set of driving wheels. Not by an eccentric.
     
  15. Hermod

    Hermod New Member

    Joined:
    May 6, 2017
    Messages:
    69
    Likes Received:
    10
    Gender:
    Male
    Location:
    Klitmoeller,Denmark
    Heritage Railway Volunteer:
    No I do not currently volunteer
    Is it going to have roller inside conrod big end?
     
  16. LMS2968

    LMS2968 Well-Known Member

    Joined:
    Sep 1, 2006
    Messages:
    1,614
    Likes Received:
    745
    Gender:
    Male
    Occupation:
    Lecturer retired: Archivist of Stanier Mogul Fund
    Location:
    Wigan
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    Not judging by the photo. The roller bearing has to be fitted before the second crank web; it cannot be fitted afterwards.
     
  17. 242A1

    242A1 Active Member

    Joined:
    Dec 3, 2006
    Messages:
    938
    Likes Received:
    322
    Check out split roller bearings. I am not saying that fitting one would have been possible but they have existed for many years.
     
  18. Hermod

    Hermod New Member

    Joined:
    May 6, 2017
    Messages:
    69
    Likes Received:
    10
    Gender:
    Male
    Location:
    Klitmoeller,Denmark
    Heritage Railway Volunteer:
    No I do not currently volunteer
    Yes, but the claimed beauty of built up cranks, is that it can be taken apart and assembled a couple of times.
    The picture shows not a pressing together opperation.
     
  19. LMS2968

    LMS2968 Well-Known Member

    Joined:
    Sep 1, 2006
    Messages:
    1,614
    Likes Received:
    745
    Gender:
    Male
    Occupation:
    Lecturer retired: Archivist of Stanier Mogul Fund
    Location:
    Wigan
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    Yes, I know. But I have still to actually see one.
     
  20. LMS2968

    LMS2968 Well-Known Member

    Joined:
    Sep 1, 2006
    Messages:
    1,614
    Likes Received:
    745
    Gender:
    Male
    Occupation:
    Lecturer retired: Archivist of Stanier Mogul Fund
    Location:
    Wigan
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    This is true, and must be done should the bearing need to be replaced. But it's a far from easy operation and one you don't do without good reason - or too often.
     

Share This Page