drgwk37 Wrote:
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> TheTrekki Wrote:
> --------------------------------------------------
> -----
> > Sadly the reason that I hear that 497 has not
> been
> > rebuilt is due to it needing a new boiler
> because
> > when it was last inspected it's boiler was too
> > thin. What I heard is that if they rebuilt it
> they
> > would have to take one of the good boilers from
> > the other K-37's. Most likely 492.
> > David
> > Phoenix, AZ
>
>
> Sorry to be rude but that would be one of the
> dumbest things that could be done and create a
> whole new set of issues when relocating a boiler
> from one frame to another. This rumor that you
> heard is one that came out of a fantasy land
> conversation on this board years ago. I think I
> stated then what a lame idea it was. Bottom line
> there are not any shortcuts when overhauling a
> locomotive. If you were going to do all of that
> you might as well take 494 and rebuild her on her
> existing frame and her existing boiler. I bet
> it's in better condition than most or all of the
> operating K36's. Just my 2 cents and my opening
> comment is not directed at you but rather that
> loon of an idea about swapping boilers! I think
> what John Bush stated sums it up....nothing
> significant to see to mot have 497 returned to
> service.
>
> William
> aka drgwk37
Where just did you get that idea from William?
Surely Burnham shops built these K-37's to a Blueprint or were there just 10 Locomotives constructed by making it up their heads as they went along?
excerpted from Wiki NZR A
B class page
here
The AB type boiler had a working pressure of 180psi, a standard across the type. These boilers were of standard construction, no matter which firm built them, and as such were interchangeable across any locomotives of the type. They were also similar to the boilers built for the WAB and WS class 4-6-4T tank locomotives in 1939 - in fact, the WAB boiler and AB boilers were the same, with those fitted to the WAB fitted with the necessary components to draw water from the locomotive's side tanks.
This type of boiler was also adapted for use on the Q and AA class 4-6-2 tender locomotives of 1901 and 1915 respectively when their original boilers wore out. In the case of the AA class, the boiler change was not necessitated by the condition of the boilers but due to the limitations of the original boilers. The replacement took place in the 1930s, and these locomotives gained new heights of reliability, before they were withdrawn in 1957 (at the same time as the Q class). All of these boilers were then put back into the AB class pool, and were reused on engines of that class.
In all, 6 separate classes used the standard AB boiler. When Q, AA and G class locomotives were scrapped in the 1950s, the boilers were overhauled to keep locomotives of A, AB, and WAB serviceable.
So to our Chief Mechanical Engineer's and Workshops Manager's, no big deal to swap Boilers, convert old locomotives to different wheel arrangements and build completely new design loco's as well.