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.

Thermodynamics, DBHP and related technical matters

Discussion in 'Steam Traction' started by class8mikado, Jul 1, 2018.

  1. 8126

    8126 Member

    Joined:
    Mar 17, 2014
    Messages:
    823
    Likes Received:
    962
    Gender:
    Male
    Perhaps unfairly, I don't consider 232U1 particularly significant in the grand scheme of French locomotives. It showed some sensible thinking in terms of simplifying operation and mechanical refinement, but didn't achieve the conceptual leap and increased power of 242A1 (on which the stillborn French 2-10-4 was based). The later Baltics occupied a fairly niche role in French motive power, only eight in total within three sub-classes, and I wouldn't say they particularly distinguished themselves compared to the much more numerous 'P' classes in terms of power or economy.
     
  2. John Baritone

    John Baritone New Member

    Joined:
    Feb 22, 2018
    Messages:
    140
    Likes Received:
    134
    Gender:
    Male
    Location:
    Buxton
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    According to Terry Essery, the first time he fired a 9F was on a goods train, at night. Admittedly, the stock was short-wheelbase stuff, but they were going fast enough that when they pulled up, the guard said to the driver that he thought they were going to have him off the road - yet Terry said he parked a mug of tea on top of the handbrake column whilst they were going at whatever speed it was, and it didn't move; all he saw was tiny concentric ripples on the surface of the tea, spreading out from the centre.
    And what about the driver whose Gresley Pacific failed on an up express to Kings Cross, and the only available spare engine was a 9F which was shunting coal wagons? The driver said that she just felt so smooth, that he just let her run - yet, according to a passenger . . . was it O S Nock? . . . she was doing 92mph at one point, and until he walked down the platform at Kings Cross to take a look, he'd assumed that the spare engine was one of Gresley's!
     
  3. LMS2968

    LMS2968 Part of the furniture

    Joined:
    Sep 1, 2006
    Messages:
    2,987
    Likes Received:
    5,084
    Gender:
    Male
    Occupation:
    Lecturer retired: Archivist of Stanier Mogul Fund
    Location:
    Wigan
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    See Posts 71 and 73.
     
  4. Hermod

    Hermod Member

    Joined:
    May 6, 2017
    Messages:
    985
    Likes Received:
    283
    Gender:
    Male
    Location:
    Klitmoeller,Denmark
    Heritage Railway Volunteer:
    No I do not currently volunteer

    A gentleman named Steve has running expirience with 9F and Austerities and the american 2-8-0.
    The austerities are by common consent unfit for human consumption doing more than 45 mph.
    They shuttle fore and aft due to having no reciprocating balance.The benefit is they give no hammerblow.
    Piston and crosshead of 9Fs must be more or less the same mass and they are 40% balanced fore and aft.
    Harmfull ness of vibration grow with square of velocity ratio so a 9F at 60 is more uncomfortable than an austerity at 45 and more harmfull to track.
     
  5. LMS2968

    LMS2968 Part of the furniture

    Joined:
    Sep 1, 2006
    Messages:
    2,987
    Likes Received:
    5,084
    Gender:
    Male
    Occupation:
    Lecturer retired: Archivist of Stanier Mogul Fund
    Location:
    Wigan
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    I'd agree with all that except for the upper speed of a WD before the shuffling sets in: 25 mph was nearer the mark!
     
  6. MellishR

    MellishR Resident of Nat Pres Friend

    Joined:
    Apr 16, 2009
    Messages:
    8,068
    Likes Received:
    5,165
  7. 240P15

    240P15 Well-Known Member

    Joined:
    Dec 1, 2017
    Messages:
    1,598
    Likes Received:
    1,588
    Gender:
    Male
    Location:
    Norway
    Heritage Railway Volunteer:
    No I do not currently volunteer

Share This Page