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Welding Boiler Pipes

Dairon421
Dairon421 Member Posts: 81
edited March 30 in Strictly Steam

Can you weld boiler pipes together? And if you can or did it before how was your experience? I just did a commerical boiler and it kicked my **** trying screw those big pipes with a gigantic pipe wrench I borrowed from my boss. I need a easy alternative lol

Comments

  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 10,374
    edited March 28

    I'm wondering what size pipes you are muscling together?

    I have used welded flanges to connect 4” steel pipes together on the near boiler piping. I have also re-tubed a boiler (1-1/2" fire tubes) where there is no welding involved, but a tool that expands the ends of the fire tubes in place.  Interesting process.  

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

  • pecmsg
    pecmsg Member Posts: 5,952
    edited March 28

    operating pressure

    pipe size

  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 17,627

    Having done it both ways threading and welding. Neither one is easy especially on the larger sizes.

    JMHO with my ability I would thread everything up to and including 4". Anything larger would be welded. But you have to know how to weld. A half **** welding job is NG.

    Anyone can learn to screw pipe together, it's the measuring and fitting allowances are the key.

    Not everyone can weld.

    Mad Dog_2Long Beach Ed
  • pedmec
    pedmec Member Posts: 1,192

    Do it both ways. No way around it on the bigger Boilers. And i refuse to do megapress on steam. the twisting of the fittings can have you going the wrong way and don't trust those o-rings against the harsh environment steam creates

    Mad Dog_2clammy
  • Intplm.
    Intplm. Member Posts: 2,601

    When we did it, the rule was two inch or less…thread the pipe. Anything larger was welded. Its a tough job either way.

  • Mad Dog_2
    Mad Dog_2 Member Posts: 8,028

    Some welded joints are ok, but you can beat screw pipe & fittings to accommodate the great expansion & contraction, especially on Steam boilers Mad Dog

    Consulting by Mad Dog & Matt Jr.
    delcrossv
  • delcrossv
    delcrossv Member Posts: 2,117
    https://forum.heatinghelp.com/discussion/comment/1850272#Comment_1850272

    +1 No swing joints with welded pipe.

    Although they do make flange expansion joints, I've never seen them on near boiler piping.

    Trying to squeeze the best out of a Weil-McLain JB-5 running a 1912 1 pipe system.
    Hap_Hazzard
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 17,627

    You will get expansion on welded pipe. Thousands (most) CI boiler in commercial buildings have welded fittings and if done properly they don't fail.

    The key point is to come out of the boiler and swing to one side for the header and make those horizontal pieces long. We all know that the welders trick of coming out of one boiler tapping and going straight back to the other tapping with no turn will rip a boiler apart although I have seen many done that exact way.

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