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  • #16
    Dear Rick and Gaplumbing, Yes the machine is portable with servo motor which is more precise as compare to cut threading machines. Secondly if in cut threading machine 1000 Pipe Nipples can be made using one header so in Rolled threading machines 10,000 and more pipe nipples can be made easily without any problems.

    We are looking forward to revolutionize the market and piping systems more easy, sufficient and cost effective .

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    • #17
      looks like i am not allowed here to give the right information. My comments got deleted

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      • #18
        Rolled threads on used for bolting, it is a common method for bolting and very precise.

        Here's a short video about rolling the threads.

        "It's a table saw, do you know where your fingers are?" Bob D. 2006

        https://www.youtube.com/user/PowerToolInstitute

        ----

        1/20/2017 - The Beginning of a new Error

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        • #19
          Bob you are right. We have convert the method of Rolled threading for fasteners into threading of Pipes. We need to inform you that the threading we do is as per ASTM standards and the threads requirements are also get fulfill as NPT and BSP standards.

          If you need any other information please feel free to contact me.

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          • #20
            Humm, there's a difference between rolling a thread on a piece of round stock and on a tube.
            What happens to the tube diameter, is there a backup roller on the ID to prevent deforming the tube.
            "It's a table saw, do you know where your fingers are?" Bob D. 2006

            https://www.youtube.com/user/PowerToolInstitute

            ----

            1/20/2017 - The Beginning of a new Error

            Comment


            • #21
              Bob thanks for asking question about Rolled threading. I really appreciate. In Rolled threaded Galvanized Pipe Nipples the ID is not an issue actually as these reduction on the ID is less 2% - 7% depending on the size of the tube. We have test the Pipe Nipple with required pressure and there was no pressure problem at all because of ID

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              • #22
                I copied some this from an older post however what you've got, I'm very familiar with the pictures since we would have to deal with it from time to time. As a former fire sprinkler fitter we would cut threads all day 5 days a week so our 300 machines would undergo a lot of wear. As a side note, a supplier once told me that pipe alloys have changed a lot and they are now more harder, less flexible. Perhaps that topic that requires further examination. Anyhow if you haven't already, please do thusly: "Disassemble and thoroughly clean the die head, dies, replace the die head onto the carriage and tighten the bolts on the die head. The die head adjusting lever must not move when you making threads as you already know. Set your dies where you like them and make sure it's not moving when your cutting a thread, make sure the "chuck" bolts are tight and the machine is greased. Use Oaty Hercules (preferred) or Rigid dark cutting oil. Dirt, sand, water are unavoidable but they contribute to poor threads so be conscious of it and refresh your oil constantly!" There can't be a lot of slop in the die head meaning if the dies wiggle a lot, it could be a problem. Rebuilding an old machine will improve things greatly but it's expensive and buying even just the power head is almost as much. For some machines I found that it was a combination of many things that affected the geometry of the pipe being threaded and it was wasnt until the machine was completely rebuilt or replaced with a new one that the issues were resolved. The Diehead is a good starting point, good luck!

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                • #23
                  When I cut pipe that big or larger, I always do it in two passes.
                  A light cut at first, followed by the full thread depth.

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                  • #24
                    Originally posted by johncameron View Post
                    When I cut pipe that big or larger, I always do it in two passes.
                    A light cut at first, followed by the full thread depth.
                    I have never heard of threading 2" (or any size) in two passes, anyone else?

                    I have a few thousand 2" threads under my belt in both black iron
                    and galvanize and have always cut threads in one pass. Even for SS
                    pipe I would not consider this method.

                    The only way to do as you suggest would be to use two dies (one set for
                    a shallow cut, the other for a normal thread depth) or reset the one die
                    every time, and get it right every time. If you're off by a smidge then
                    your thread will seat a little deeper (or shallower) on each joint making
                    for a PITA when you try to achieve a certain C-C distance.
                    "It's a table saw, do you know where your fingers are?" Bob D. 2006

                    https://www.youtube.com/user/PowerToolInstitute

                    ----

                    1/20/2017 - The Beginning of a new Error

                    Comment


                    • #25
                      Always did pipe in a single pass, unless a fine adjustment of deeper cuts were needed. Even 4" was cut in 1 pass.

                      Rick.
                      phoebe it is

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                      • #26
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                        • #27
                          Open/Close handle can be manipulated (usually halfway) to slightly disengage dies during the first cut. Then, Back off and then restart with adjustment fully down (closed). I've been doing this for about 30years and get perfect threads every time. It takes about 20 or so seconds for two passes on 2 in Npt.

                          ​​​

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                          • #28
                            I don't think any of us needed a picture to refresh our memories. At least I don't.

                            What you do may achieve what you claim but is certainly not how the die is designed
                            to be used and I doubt there are many who do this.

                            Perfect threads should be the result of using the die as the manufacturer intended, not
                            the result of a work-around.
                            "It's a table saw, do you know where your fingers are?" Bob D. 2006

                            https://www.youtube.com/user/PowerToolInstitute

                            ----

                            1/20/2017 - The Beginning of a new Error

                            Comment


                            • #29
                              Originally posted by Bob D. View Post
                              The only way to do as you suggest would be to use two dies (one set for
                              a shallow cut, the other for a normal thread depth) or reset the one die
                              every time, and get it right every time. If you're off by a smidge then...
                              Ah, I just showed you another way to do it with the same die.
                              ​​​
                              Tradesmen do this all the time in these parts, and I see nothing wrong with it. It reduces heat, saves wear and tear on the equipment, makes for cleaner threads, and can be repeated with accuracy.


                              Not saying there's not an underlying problem here, I'm just saying what I do that works. If the die is set-up correctly it's probably just bad batch of pipe.

                              ​​​​​​​Oh, and I'd like to apologize for that picture. That was just wrong.




                              ​​​​​​

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                              • #30
                                our go to machine for production threading was a collins 22a. The die head was not the same. it would lock into a set position and that was all it took. once properly adjusted, it would duplicate the same thread all job long.

                                Rick.
                                phoebe it is

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