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Hi to all,
I am working on 2 smith gsx 288,000 steam boilers that are united together by a knucklehead near boiler piping marriage.
The Smith boilers have two 3" trappings on top.
Each boiler has one 2" riser, and a 3" plug
The header is 4" with 4" main feeding the building
1. Would adding a 3" riser be beneficial with the existing 2"?
2. Any ideas on getting a 3" plug out that is buried flush with the cast iron section, 4ft pipe wrench did not work.


  • Jamie Hall
    Jamie Hall Member Posts: 23,275
    Short answers: 1. Yes, a lot. 2. Not a clue...
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    EBEBRATT-Ed Member Posts: 15,517
    I would rework the piping as shown in the MFG installation instructions.

    Getting the plug out will be difficult. Try KROL OIl or another penetrating oil but it probably won't work. Knock it with a hammer a few times.

    Drill a series of holes maybe a 1/4" diameter 1/2" in from the outside edge of the plug. Then saw between the holes and knock out the middle. (don't let it fall in the boiler) Now you can use a sawzall to cut towards the threads. Do this in 3-4 places. Try not to hit the threads. Then use a cold chisel.

    It won't be easy. The plug is cast iron which won't peel away like steel will. You will get little bits at a time.

    Once you get a chunk out of the threads and "break the arch" it should come out.
    JUGHNE Member Posts: 11,060
    There is a posting (I found in search) by Icesailor. He said he used a hole saw a little smaller than the opening. Drill thru then saw to threads. A little oil on the holesaw. Boiler may need skimming/wand washing afterwards.
  • ratio
    ratio Member Posts: 3,624
    Maybe treat with penetrating oil for a few days, then heat the block with a torch for a while, then hit the plug with some ice & immediately wench it with the 48"er.
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
    Maybe an impact wrench will make this easier.--NBC