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Threaded connections

HOJplumberHOJplumber Member Posts: 1
I work as a building plumber for The City and County of San Francisco. The Stationary (boiler) Engineers I answer to often have me impersonate a steamfitter (usually to replace valves) and work on steam and hydronic heating lines in the building. For copper tube lines I braze ("silver/hard solder") the connections, but for the threaded connections I use the same Blue Magic or Rectorseal brand pipe dope and teflon tape that I use for potable water. Before manning the plumbing/piping shop at this bulding by myself, I was part of a crew of plumbers and genuine steamfitters who shared a shop (though we had seperate locker rooms as well as seperate supervisors who each answered to the same stationary engineer). When I called my vendor (who have the word steam in their name) to ask what I should use for high heat threaded connections they just say to use Blue Magic, but I remember that the steamfitters used a different kind of pipe dope that was grey in color, so I suspect that their must be pipe dope and tape that is better for steam and hydronic heating lines. I haven't found any answers in "Modern Hydronic Heating" or in Dan's books so I'm asking you. Please tell me what to use for threaded heating piping and components.



  • JaredMJaredM Member Posts: 57
    Pipe Dope for Steam

    This subject has been argued by folks for years.  Do some searches on this board and you will find all manners of opinions.

    For steam and water I use single strand wicking and a good quality pipe thread compound.  I usually grab some flavor of teflon based pipe thread compound. 
  • RJRJ Member Posts: 484
    pipe dope

    For fittings i never want to leak i would use expando or grip.   Our you at the Hall of Justice, I worked for a co. that did alot of work there, i knew Manee , he retired also Knew Renee and Tom.     Retired fitter Rick
  • gennadygennady Member Posts: 680
    edited April 2013
    Pro dope

    Pro dope is the best and only tread joint compound right for job.
    Gennady Tsakh

    Absolute Mechanical Co. Inc.
  • Cal Steam

    in the Bay Area sells all the usual stuff: Recorseal, Blue Magic, etc.  The grey dope that you mention sounds like a specialty product.

    If I have a difficult connection, say a large, pitted fitting where I have to start my piping or a European fitting that has no taper, I use Super Dope; it works anaerobically.  I've tried it on new fittings with only hand tightening - no leaks!
    Often wrong, never in doubt.
  • SteveSteve Member Posts: 486
    Pro dope

    Is gray

    Seems very popular on the east coast
This discussion has been closed.


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