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.

60007 (4498) Sir Nigel Gresley Overhaul

Discussion in 'Steam Traction' started by No.7, Mar 25, 2016.

  1. green five

    green five Resident of Nat Pres

    Joined:
    Apr 30, 2006
    Messages:
    6,596
    Likes Received:
    2,242
    Gender:
    Male
    Location:
    Hampshire
    Heritage Railway Volunteer:
    No I do not currently volunteer
    Quite right about 6201, 71000 and D213. I wasn't sure what other arragements had been set up.
     
  2. Thompson1706

    Thompson1706 Part of the furniture

    Joined:
    Nov 19, 2007
    Messages:
    2,438
    Likes Received:
    1,844
    Gender:
    Male
    Occupation:
    Retired
    Location:
    Rhiwabon
    Heritage Railway Volunteer:
    Yes I am an active volunteer

    Attached Files:

    JEB-245584 likes this.
  3. Steve

    Steve Resident of Nat Pres Friend

    Joined:
    Oct 7, 2006
    Messages:
    11,930
    Likes Received:
    10,088
    Occupation:
    Gentleman of leisure, nowadays
    Location:
    Near Leeds
    Heritage Railway Volunteer:
    Yes I am an active volunteer
  4. northernsteam

    northernsteam Member

    Joined:
    May 25, 2010
    Messages:
    593
    Likes Received:
    271
    Gender:
    Male
    Occupation:
    Used to be in civil engineering, highway bridges.
    Location:
    Tyne and Wear
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    Perhaps there is some confusion with the method being used here? It looks a bit as if a cutting torch is being used, whereas I assume they are being cut with a grinder, which is quite accurate enough and leaves a tidy edge, if done by a trained worker!
     
  5. W.Williams

    W.Williams Well-Known Member

    Joined:
    Dec 20, 2015
    Messages:
    1,585
    Likes Received:
    1,465
    Occupation:
    Mechanical Engineer
    Location:
    Aberdeenshire
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    You are joking I presume.

    I said trestle. So obviously they would be out of the box.

    If that’s a grinder that’s in my eyes almost worse!

    Is it such a hassle to measure the tubes and cut them to the correct length?!
     
  6. JEB-245584

    JEB-245584 Member

    Joined:
    May 21, 2008
    Messages:
    375
    Likes Received:
    390
    Occupation:
    ADI
    Cutting off the flue tubes in situ is an acceptable practise ( see attached file)

    Also the picture was taken by a senior member of the SNG's engineering team, and the work is being overseen/ carried out by one of the industry's most experienced boilersmiths, so I think everything is just fine.
     

    Attached Files:

    jnc and W.Williams like this.
  7. W.Williams

    W.Williams Well-Known Member

    Joined:
    Dec 20, 2015
    Messages:
    1,585
    Likes Received:
    1,465
    Occupation:
    Mechanical Engineer
    Location:
    Aberdeenshire
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    Thanks for the info. :)
     
  8. Steve

    Steve Resident of Nat Pres Friend

    Joined:
    Oct 7, 2006
    Messages:
    11,930
    Likes Received:
    10,088
    Occupation:
    Gentleman of leisure, nowadays
    Location:
    Near Leeds
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    I was expecting Estwdjhn to come galloping in on his white charger to give good reasons but, as he must be too busy bashing boilers, I'll have a go. Boilers are usually built and repaired by boilersmiths. They are 'smiths', who, like blacksmiths, coppersmiths and tinsmiths generally bash bits of metal around. That's where the name comes from (to smite.) Boilersmiths don't generally work to the nearest thou, only the nearest boiler. They also tend to use a BBH (bloody big hammer) and that BBH isn't a precision piece of kit. Whilst tubeplates are, in theory, flat bits of metal, once they have been talked to with a BBH and other brutal bits of kit they aren't that flat or indeed parallel to each other and the distance between them can vary by quite a bit, even on the same boiler. I've known tube lengths differ by as much as 1" over the width of the boiler.
    As I generally play with industrial loco boilers I don't really have any personal experience of installing superheater flue tubes but have watched it done on several occasions. First job is to tap a thread in the copper tubeplate and cut a 45 degree chamfer on the water side. You do this with a tap on the end of a long mandrill. If you are lucky you will have a machine to do the job. See:

    There will be a chap in the firebox keeping an eye on things and shouting instructions to the operator at the smokebox end so it isn't a precision machining job. When you then come to install the tubes you might have a fancy tube driver to screw the flue in as in this next video:,

    In which case you could measure each tube and cut to length, taking a good guess as to exactly how long it will need to be to stick out the requisite amount when screwed fully home. Expensive if you make a mistake, though! However, I've never seen one of these tube drivers and whenever I've seen it done the practice has been to weld a suitable driver onto the end of the tube and screw it in with an air driven tool or a big ratchet. You don't have a driver for each flue to you have one and weld it to a tube. When the tube is installed, you cut it off and weld it to the next tube. It goes without saying that the tube has to be over long. You then trim the tube to the correct length, ready for expanding. Doing it this way, even if you have a posh driver, reduces the risk of mistakes. As I said, writing off a flue tube that it too short is an expensive mistake.
    The above is just my take on the subject.
     
    ghost, 8126, Bluenosejohn and 7 others like this.
  9. huochemi

    huochemi Part of the furniture

    Joined:
    May 6, 2008
    Messages:
    2,751
    Likes Received:
    1,393
    Gender:
    Male
    Location:
    UK
    Heritage Railway Volunteer:
    No I do not currently volunteer
    Do you mean a mandrel?;)
     
    MellishR likes this.
  10. Steve

    Steve Resident of Nat Pres Friend

    Joined:
    Oct 7, 2006
    Messages:
    11,930
    Likes Received:
    10,088
    Occupation:
    Gentleman of leisure, nowadays
    Location:
    Near Leeds
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    Do you mean as a technical term for posh driver? Not exactly, although I guess it incorporates one although I wouldn't really consider it as such, more a wedge. The 'posh driver' is a piece of kit(another technical term!) which is inserted in the tube end and a hexagonal mandrel/wedge pushes out jaws which grip the tube when it is rotated. Have a look at page 9 of https://static1.squarespace.com/sta...B9001-Is02+-+Tubing+of+Locomotive+Boilers.pdf for a sketch of one. They obviously exist but I've never seen one.
     
  11. huochemi

    huochemi Part of the furniture

    Joined:
    May 6, 2008
    Messages:
    2,751
    Likes Received:
    1,393
    Gender:
    Male
    Location:
    UK
    Heritage Railway Volunteer:
    No I do not currently volunteer
    I was wondering what a "mandrill" was.
     
  12. The Green Howards

    The Green Howards Nat Pres stalwart

    Joined:
    Feb 20, 2016
    Messages:
    14,119
    Likes Received:
    7,644
    Occupation:
    Layabout
    Location:
    Naughty step
    Heritage Railway Volunteer:
    No I do not currently volunteer
    [​IMG]

    Mandrill.
     
    MellishR and craigy like this.
  13. 61624

    61624 Part of the furniture

    Joined:
    Sep 27, 2006
    Messages:
    5,294
    Likes Received:
    3,596
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    I thought it was a big drill turned by hand!:)
     
  14. huochemi

    huochemi Part of the furniture

    Joined:
    May 6, 2008
    Messages:
    2,751
    Likes Received:
    1,393
    Gender:
    Male
    Location:
    UK
    Heritage Railway Volunteer:
    No I do not currently volunteer
    I wondered if it was a disrespectful term to those wielding the big hammers.
    Visions of Arny ripping the business end off a pillar drill and wielding it on the tube plate.
     
  15. Steve

    Steve Resident of Nat Pres Friend

    Joined:
    Oct 7, 2006
    Messages:
    11,930
    Likes Received:
    10,088
    Occupation:
    Gentleman of leisure, nowadays
    Location:
    Near Leeds
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    Oops. Missed that one!:Shamefullyembarrased: I can't even think of an excuse.
     
  16. MellishR

    MellishR Resident of Nat Pres Friend

    Joined:
    Apr 16, 2009
    Messages:
    8,069
    Likes Received:
    5,165
    I'm wondering whether this discussion (the one about boilers, not the one about monkeys) should be moved to the Boiler design & construction ex Patriot thread. While it's here, I have a question. If the flue tube is screwed into the tube plate at one end, what is the equivalent means of fixing at the other end?
     
  17. gwalkeriow

    gwalkeriow Well-Known Member

    Joined:
    Aug 17, 2009
    Messages:
    1,703
    Likes Received:
    1,727
    Gender:
    Male
    Occupation:
    Retired.
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    Tube expanders in the same way that the small tubes are fitted.
     
  18. Davo

    Davo Well-Known Member

    Joined:
    Oct 12, 2018
    Messages:
    1,523
    Likes Received:
    634
    Gender:
    Male
    Location:
    W yorkshire 56f
    Heritage Railway Volunteer:
    No I do not currently volunteer
    I'm not sure myself but is it when the other end of the tube is expanded by inserting a expanding driver inside on a drill to push out the ends of tube making it a tight fit in the tubeplate? Then it is bottlecapped over using a pneumatic drill with a specially shaped tool on it like a hook shape. As you hammer away round the end of the tube you move it round the full circumference end of the tube and it flattens it out over the tube plate making it water tight, so only heat goes through the tube. This last process is called capping or rimming
     
    Last edited by a moderator: Feb 5, 2019
    jnc likes this.
  19. marshall5

    marshall5 Well-Known Member

    Joined:
    Oct 26, 2010
    Messages:
    2,377
    Likes Received:
    3,981
    Location:
    i.o.m
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    The process is called beading - rimming is something completely different!
    Ray.
     
    GWR4707, Spinner, W.Williams and 3 others like this.
  20. Davo

    Davo Well-Known Member

    Joined:
    Oct 12, 2018
    Messages:
    1,523
    Likes Received:
    634
    Gender:
    Male
    Location:
    W yorkshire 56f
    Heritage Railway Volunteer:
    No I do not currently volunteer
    So beading then is sealing the ends of the tubes. Beforehand to that is that process called tube rolling when the tubes are expanded around the tubeplate hole is that, been drive expanded?
     

Share This Page