Re: A question for all you boiler specialist

rehunn Wrote:
=======================================================
> To David's thought and Bill's statement, there is
> no forced draft in a
> locomotive unlike a fan driven HVAC unit. You
> create a draft, or negative
> pressure zone, in the smokebox by introducing
> steam or by cylinder exhaust
> steam. Because of that you want a minimum pressure
> reduction through the
> flues and tubes to enhance combustion in the
> firebox. As to tube material
> I've always used fully annealed seamless tubing.
> One of the advantages of
> seamless is that you reduce the chance of the
> seams splitting when rolling
> the tubes into the sheet.


Great choice seamless would be the smartest route to take, no need to create an option for the pressurised steam to weaken and find a way to escape. So what is the advantage of fully annealed material? That would be the soft end of a heat treating process after the pipe is constructed. Other then it would be easier to shape on both ends of the firebox and smokebox sheets. Does the annealed pipe actually go through a heat treating process everytime the locomotive is steamed up?

Still a Student,

Dave