Subject: Re: (fwd) Re: thermite for molten iron casting???

From: [email-masked] (David Hoopes)
Date: Wed, 4 Jan 1995 16:23:10 GMT

According to Alan Richer:
}
}Greetings, and a question if I may:
}
}In your directions on the forge burner, you describe (as I can imagine)
}a T  made of 2 12" pipes, with a 1.5" and a 1" pipe welded inside. I'm a bit
}confused here...
}
}Why the triple pipes? Wouldn't capping the 2-inchers and drilling the pipe for
}gas jets have much the same effect?
}
This isn't just propane at this point.  It is air supplied by a electric
blower mixed with propane.

}The reason I'm asking is that it seems that the 2-flame setup
} that would arise from this would be inefficient and cause a soot build-up.
}This could be ungood for some processes...
}
}   Pardon the question -ajr
}As referenced....
}
}Screw the two pieces of 2 in pipe into the elbow.
}
}Attach blower to one end.
}Drill and tap a hole in the elbow near the blower end of the elbow (just
}above where the threads of the straight piece stop)
}
}Screw in the 1/2 in pipe.  Attach valve, propane line, and regulator.
}
}on the business end, insert the 1 1/2 in piece.  Use three wedges to hold
}it in place so that it is centered inside the end of the 2in pipe.  Hammer
}these in good. If you have a welder, you might weld these in.  ( I didn't,
}and I havn't had any problems, but I always over do it if I can). 
} 
}Put the 1 in piece inside the 1 1/2 in piece and wedge it in the same way.
}
}Stick it through the hole in the side of the forge/furnace.  Use large
}amounts of bailing wire to hold everything in place.
}
}Make sure that you turn on the blower first, then turn on the propane.  I
}always wad up a piece of newspaper, light it through it into the forge,
}and then turn everything on.
}
}Hope someone finds this useful :-)
}
}

No, there will only be one very big flame.  The two smaller pipes are
there simply to mix the propane and air.  I have seen several variations
of this set up, and tried a couple of them.  I didn't detect much
differance when using the different defussers.  One was as simple as a wad
of chicken wire stuffed into the end.

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 ===========================================                      |
                                           |                      |
                                           |                      |
                                           |                      |
                                           |                      ----
                                           |                       Propane
                                           |                      ----
                                           |                      |

                                                      ^
                                                      |
                                                     Air

Maybe this drawing will make it a little clearer what I was talking about.
There will not be any soot.  By adjusting the air flow, and watching the
flame you can adjust it so that it is a reducing flame.  At that point you
will have a blue inner core inside the flame that is 4-6in long.

-- 
David Hoopes                              Exabyte Corp.
[email-masked]                       11100 W 82nd St.          
Voice: (913) 492-6002 x3323               Lenexa, Ks  66214