Melting burners

Melting burners

Post by Dick Lehm » Sun, 09 Feb 1997 04:00:00



At the state college where I blow glass, the furnace had trouble last
summer. The burner and its support system drifted off center and got
too much flame on the outside, damaging the side wall a lot. So one of
the grad students rebuilt the side wall and the burner assembly. Did
what seemed to be a nice job, too.

But here's the problem. When they fired up the furnace, it got so hot
that it melted the burner head. So they made a new one. It melted, too.
The first one looked to me to be too far inside the furnace chamber. I
never saw where the second one was installed, but they moved it out
some, I believe. The shop has a brand new Giberson burner, but they're
understandably a bit nervous about installing it.

I've looked through everything I have about building furnaces (not
much! but I do have Halems _Glass Notes_ and a few little notes in
other places. Nothing addresses this problem. In fact, nothing says
anything about how to install burners. I figure there's only a couple
of ways to mess up. You can have the port too large or too small for
the burner, or you can put the burner too far in or too far out.
(There's plenty of gas pressure and air, and the previous burner head
lasted 8 years or so in the same furnace.)

Can any of you furnace workers out there offer any suggestions? Exactly
WHERE does the burner head go? How big should the port be relative to
the burner? Anything else that might help these folks? (Helping them
will, of course, help me, too, even if it's not MY shop.)

Thanks.

------------------------------------------------------------------------
--

Professor of Psychology       (That's R-underscore-Lehman)
Franklin & Marshall College            Voice (717)291-4202
PO Box 3003                              FAX (717)291-4387
Lancaster,  PA  17604-3003
               "I'd rather be blowing glass."

 
 
 

Melting burners

Post by Phil Taylo » Sun, 09 Feb 1997 04:00:00


Hi***,
        I don't have an answer or solution for your furnace and burn-out
(burn-up?) problem.  Just wondered if you knew*** Nissely or Keith
Spalding, two people from Lancaster who used to visit us every summer.  
*** Nissely is a retired highway engineer and currently owns a winery
there.  And, I believe, that Keith Spalding was once President of F & M.
 Let us know.  T. in Montana

------------------------------------------------------------------------> --

Quote:

> Professor of Psychology       (That's R-underscore-Lehman)
> Franklin & Marshall College            Voice (717)291-4202
> PO Box 3003                              FAX (717)291-4387
> Lancaster,  PA  17604-3003
>                "I'd rather be blowing glass."


 
 
 

Melting burners

Post by Roger Peterso » Mon, 10 Feb 1997 04:00:00


Dick,

Call Dudley Gibberson at Joppa Glasswork

Joppa Glassworks, Inc.
P.O. Box 202
Warner, NH  03278

Phone: (603) 456-3569
  Fax: (603) 456-2138

If Dudley does not know what to do, it most likely can't be fixed.

Roger...

 
 
 

Melting burners

Post by mikefi.. » Tue, 11 Feb 1997 04:00:00



Quote:
Lehman) writes:
>I figure there's only a couple
>of ways to mess up. You can have the port too large or too small for
>the burner, or you can put the burner too far in or too far out.
>(There's plenty of gas pressure and air, and the previous burner head
>lasted 8 years or so in the same furnace.)

>Can any of you furnace workers out there offer any suggestions? Exactly
>WHERE does the burner head go? How big should the port be relative to
>the burner? Anything else that might help these folks? (Helping them
>will, of course, help me, too, even if it's not MY shop.)

  Gibberson's "catalog" and the instructions that come with his burners
give very precise directions for placing the burner.
  The burner should be placed so that its front face is even or a little
(1/4") outside the castable forming the furnace.  The port should be
barely larger than the burner and ideally should taper so the small end is
at the burner.   A small amount of frax should be used to fill the crack
without encasing the burner head.  The head should not be surrounded with
insulation of any kind.  The furnace should have venting, either a leaky
door or a flue so that back pressure does not force hot gas past the head.
 I use both a Gibberson head and a flared iron pipe burner and neither has
"melted".  I would be surprised if a Gibberson head melted, cracked maybe,
melted? No.
  If a burner is fired up and the flame starts inside the pipe rather than
at the end, the pipe will soon get red hot.  If this happens, the burner
needs to be shut down and restarted with more air flow.  
  If the burners were redesigned after the first failure, the pipes may
have been increased in size without putting a proper flare on the end to
hold the flame.

 Mike Firth, Hot Bits furnace glassblowing newsletter

 
 
 

Melting burners

Post by Robert Mill » Thu, 13 Feb 1997 04:00:00


Quote:

>Can any of you furnace workers out there offer any suggestions? Exactly
>WHERE does the burner head go? How big should the port be relative to
>the burner? Anything else that might help these folks? (Helping them
>will, of course, help me, too, even if it's not MY shop.)

        the burner head should be recessed as far as you can get it ( not
knowing the actuall structure I cant give you dimmensions) Also  your
air\gas ratio is critical. to much gas and the burner will overheat.
Run it as lean as you can get away with . Placement within the
structure is not all that critical . ( I locate mine about 1\2 the
length of the furnace) You do have to have either a decent size port
or an exaust flue . ( the port should be as large or larger than the
burner) but from what I have read of your post I would bet that the
burner was running to rich.
        I am not an engineer, but I have built a variety of burners,
furnaces,annealing ovens, etc. and have run into most of the common,
( and sometimes not so common) problems.
        If I knew the actual structure dimmensions, type of insulation,etc I
could probebly be more specific about the cure. but my money is on the
over-rich air\gas ratio.
        Robert Miller  c / o
         Lundberg Studios