Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

what is radius of long turn copper sweat fittings (and press)

archibald tuttle
archibald tuttle Member Posts: 1,090
edited February 2021 in Plumbing
Trying to find drawings or industry standard specifications for long turn radius by tubing size in copper. I find various discussions of long turn vs. standard radius that suggest standard radius is 1 time pipe dimension and long turn is 1.5 times. But they don't indicate where the radius is measured (or whether that is a standard for copper or steel or . . . )

this is actually a non plumbing application for mid-range diameter (1 and 1/2"). I don't find that suppliers list a radius or offer drawings. Charlotte has great drawings of their PVC fittings available which I often use when working in close quarters and wondering what i would save with size changing street wyes and tee wyes but I can't find anything like it for copper either by industry standard or manufacturer.

as it happens this macgyver is with sweat fittings although I have occasionally been used to obtaining long turn or looser radius elbows from some manufacturers of propress fittings and likewise, if these radiuses were better known and called out by manufacturers or industry i think it might improve availability of these fittings which can be really handy for configuration and/or desirable to reduce pipe friction.

appreciate if any other retentive pipers out there could pipe up on this question.




  • ratio
    ratio Member Posts: 3,696
    edited February 2021
    Refrigeration use fittings are generally sweep fittings. My advice would be to get one & measure it—I've not that I recall seen a dimensioned drawing for them (I've not looked for one, however). Keep in mind that refrigeration tubing is measured by the outside dimension, not the inside like plumbing. To get a ½" sweep 90°, order a ⅝" 90°; to get a 1" sweep 90°, order a 1⅛" 90°.
    EBEBRATT-Ed Member Posts: 15,829
    The raidus is measured from where the fitting starts goes to go from straight to where it just starts to turn to the center of the bend
  • archibald tuttle
    archibald tuttle Member Posts: 1,090
    @Youngplumber that's just what i was looking for. thanks

    @EBEBRATT-Ed i think you are kind of describing the C or D dimensions in the sweat long turns depicted in the nibco catalogue. these drawings/pics are great but i would figure the radius, if expressed as a specification number rather than through drawing would be most easily stated as the radius to the center of the quarter arc from the centerline of the pipe diameter in the fitting, which I believe is effectively the same number arrived at in the drawings, but they don't actually show it as a radius. that does correspond to the general convention I had found online that the radius of long turn is 1.5 times the tubing size. 1.5 inch tubing long turn has radius to centerline of 2.25 according to the drawings.