Building Beeg Boy.... (LOTS of pictures)

Discussion in 'Scratchin' & Bashin'' started by doctorwayne, May 13, 2008.

  1. doctorwayne

    doctorwayne Active Member

    Well, I understand how the injectors work, and, as Bernhard points out, the injector does impart heat to the water. But that raises the question of why railroads would then bother with a feedwater heater system at all.
    From reading further in the Locomotive Cyclopedia, it seems that the answer is in fuel savings - the otherwise waste heat from the exhaust steam used in a fwh is sufficient, on average, to raise the water temperature by 160 deg F. - with feedwater at 60 deg., that's 220 deg. F. as the water enters the boiler, all of that gain at almost no extra cost in fuel. (Some boiler steam is used to run the cold water pump.)
    In an injector, the water temperature is raised only to 180 deg. F., but the "live" steam required had to be produced by the boiler for this purpose: in other words, fuel had to be burned to produce the steam solely for the operation of the injector.
    Either way, whether at 180 deg. or 220 deg., the fire still has to raise the water temperature to about 600-650 deg. F., the normal operating temperature of steam in the boiler at normal operating pressures.

    Because the water from an injector is impelled by live steam at boiler pressure, it's able to open the boiler check valve, admitting the water. In a fwh, using waste steam at lower pressure, the check valve is held open by pressure supplied by the cold water pump.

    I appreciate all the assistance and information added by others, and welcome more - my information is only from books, so first-hand knowledge is particularly useful.

  2. ocalicreek

    ocalicreek Member

    Efficiency is the name of the game in 'Modern' steam locomotives. So many of the devices and appliances on late model steam are all about making the most of the fuel burned and resulting steam. Thanks to all for such great explanations. I had wondered about the injector/temperature issue as well.

    Wayne - I'll be revisiting this thread often as a source of inspiration and motivation for my own projects. Your step-by-step photos, well, it's gleaming eye-candy for anyone who appreciates steam and/or detailing, but more than that, it's helpful too!

  3. cnw1961

    cnw1961 Member

    Wayne, all I can add is WOW :inw::inw::inw:.
  4. zigzag_i

    zigzag_i New Member

    This is very nice work doctorwayne.

    I really appreciate all the in formations you gave for this project. It will come handy for me in a near future. Have a look at my other tread "CN Consolidation".

    Where did you find the Canadian National plate in front?


  5. doctorwayne

    doctorwayne Active Member

    Thanks, Luc. The front number plate is from the CNR SIG: they're etched brass and come in sheets of 60 plates - supposedly, there is one for every CNR steamer ever built, although I've found some difficult to get. You have to paint them red, then use very fine (#1000 or finer) sandpaper to remove the paint from the raised numerals and roadname. Very credible number plates can also be made using Microscale set 87-1019. They supply several number plate decals, to which the modeller adds the individual digits. The set includes various heralds, all of the small lettering for the air tanks, cylinders, tender, etc. and cab numbers. I use the etched brass cab numbers, also from the CNR SIG, and brush paint them after the locomotive has been painted.


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