----- Original Message -----
From: Harry Wade <[EMAIL PROTECTED]>
To: Multiple recipients of sslivesteam <[EMAIL PROTECTED]>
Sent: Monday, February 04, 2002 10:02 AM
Subject: Re: Other boiler related topic
>
> >what do you think in terms of brushes in copper flues?
>
> Well, I may not be able to help you much, not ever having had an
> operating coal burner ("operating" being the key word), and not having
paid
> all that much attention to my large scale guys when they were cleaning
out.
Harry and Richard and List,
I HAVE spent many years with coal fired engines, and Harry is right that you
won't be doing any apreciable damage if you were to agressively clean every
week for the rest of your life. If anything, you will find wasting of the
boiler at the tube plates where the unburned coal and other by-products of
burning attack the tube sheet as they leave the fire. And what you will see
disappear is the silver solder from around the joints. In my larger scale
(1/2" & 3/4" scales) locomotives, the only real wear/ wasting, was to the
superheater elements. These are not cooled by steam, when the throttle is
closed, such as when you are drifting, or waiting in a station. These get a
sand blasted look to them, and will wear out long before any other failures
occur. It is just part of the facts of life that if you have superheaters,
they will wear out, and you will have to replace the elements return bend.
My solution? Get rid of the superheater! I have yet to notice any difference
in steaming, and I still feel there is much more to be gained by syphons in
the firebox, than superheaters in the tubes. So, again, clean away with your
nylon brush, or even gently with a wire brush. Don't bother to try and make
it shiney, no one can see in there anyway! And cold water hydo test every
year to make sure that the silver hasn't all disappeared from the joints
around the tube sheet. I also do not believe in over testing your boiler.
You do NOT need to pressure tesst to anything more than one and one half
times the working pressure. You will just end up deforming the sheets, and
that movement will work harden the areas where movement takes place. So
don't over stress the boiler in the name of testing, you can cause more
damage than you'll find!
Keith Taylor
