Miller Electric

Welding Discussion Forums

Home » Resources » Communities » Welding Discussion Forums

The forum is currently undergoing maintenance and is in a 'read-only' mode for the time being. Sorry for the inconvenience.


  • If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Announcement

Announcement Module
Collapse
No announcement yet.

Air compressor piping

Page Title Module
Move Remove Collapse
X
Conversation Detail Module
Collapse
  • Filter
  • Time
  • Show
Clear All
new posts

  • Air compressor piping

    I just purchased a Kobalt 60 gallon compressor and I have a question on the recommended pipe size to run in the garage. The tools I am looking to use are spray gun, D/A sander, impact/ratchet wrenches. From the factory the tank has a 2"x3/8" reducer which I was thinking of changing that to a 2"X3/4" then run some 3/4" copper pipe. The overall run will be around 40-60 ft around the room with 3 drops, depending on the elevation I am guessing drop lengths of 5ft or so.

    What do yoy guys run or recommend?

  • #2
    3/4" copper is my suggestion. 1/2" is adequate for what you described but the reduced air speed in the larger pipe will increase the time to cool thereby dropping more moisture.

    Scott

    Comment


    • #3
      I read somewere that copper and pvc have a tendency to seperate under pressure and they suggestd that you use cast iron pipe! it was on another post somewhere on here. I"ll trie to find it if I can its realy interesting.

      Comment


      • #4
        Visegrip:
        Ridgid PVC is NOT gas pressure rated. When a water pipe splits open there is only a spray of water as the water is not compressed to many times its normal volume. There is little explosive action. Compresed air expands and the explosive action of the expanding gasses can throw shrapnel everywhere.

        mxtras:
        There are thousands of articles readily accessable about the dangers of using PVC for compressed air. To summarize all of these articles: Don't use PVC for compressed air systems.

        EDITED: I retract my approval of PVC. :embarrassement:
        Last edited by Craig in Denver; 02-28-2008, 09:35 PM.

        Comment


        • #5
          I would go 3/4 because you will get more volume (CFM) to your tools. Black pipe would be the best, but very time consuming to run. I have PVC in my shop even though they say you should not use it. I haven't had a problem with it yet.

          Comment


          • #6
            If we want these forums to stay clean an neat .
            We should moderate ourselves and try to post in the correct forum.
            This should maybe be in the Disussion Forum.

            Never use pvc.
            Under pressure if you hit it with a hammer or a object. it will shatter with sharp projectiles and cause very serious injury or death.

            Copper or black iron
            there is a special plastic or similar type pipe for air ,but I cant rember the name right now.

            Rich

            Comment


            • #7
              play nice please

              If we want these forums to stay clean an neat .
              We should moderate ourselves and try to post in the correct forum.
              This should maybe be in the Disussion Forum.

              this is one of the points i made before the change and why it was a bad idea. many people ( myself included) don't care what section they are in or are not shore which is the right one.
              next we have members telling others they did it wrong or control your self, before long the screw you , bite me starts and we loose members. so let it go, if he wants it here he will post it here. its his question, let him categorize it.
              maybe he has a nascar paint booth. painting car's is not motor sports??? i think it is. let others make there own choices.

              Comment


              • #8
                Ridgid PVC is NOT gas pressure rated. When a water pipe splits open there is only a spray of water as the water is not compressed to many times its normal volume. There is little explosive action. Compresed air expands and the explosive action of the expanding gasses can throw shrapnel everywhere.
                Copper pipe will work well and does not have internal rust issues that black pipe can. High pressure and humid air tends to eat the insides of iron pipe and can spit oxide into your tools. $ no object? $tainless $teel. Home use, the plan you have looks good 3/4 for the mains and 1/2 for the drops is standard. Add some drop legs with blow out valves so you can clear ant water that condenses and rund down the drops and keep it from getting into your tools.
                Last edited by Vicegrip; 02-28-2008, 07:20 AM.

                Comment


                • #9
                  I used 3/4 black pipe and it turned out real nice.

                  Comment


                  • #10
                    There are thousands of articles readily accessable about the dangers of using PVC for compressed air. To summarize all of these articles: Don't use PVC for compressed air systems.

                    I recently plumbed my shop for air and while I wanted to use copper, the cost was prohibitive. Copper has come down since then. I ended up using black iron pipe. I ran a 3/4" trunk circuit with 1/2" drops every 12'. My shop measures 38'X50' with 16' ceilings.

                    If you use copper, you should use either type L or K. L is identified with blue markings and K is identified with green markings. Type M is marked red and is not recommended but it will hold 125PSI.

                    Scott

                    Comment


                    • #11
                      You might want to check on the 2" x 3/8" reducer outlet fitting...

                      On my 60 gallon tank the reducer is straight pipe/o-ring sealed not the typical tapered pipe plug readly available at plumbing supply houses.

                      While you could attempt to "seat" a taper into the straight threads welded into the tank a drill/tap combination can make the reducer any thread size you wish and most likely would never leak!

                      Comment


                      • #12
                        Originally posted by fun4now View Post
                        If we want these forums to stay clean an neat .
                        We should moderate ourselves and try to post in the correct forum.
                        This should maybe be in the Disussion Forum.

                        this is one of the points i made before the change and why it was a bad idea. many people ( myself included) don't care what section they are in or are not shore which is the right one.
                        next we have members telling others they did it wrong or control your self, before long the screw you , bite me starts and we loose members. so let it go, if he wants it here he will post it here. its his question, let him categorize it.
                        maybe he has a nascar paint booth. painting car's is not motor sports??? i think it is. let others make there own choices.
                        I didn't tell anyone to do anything other than moderate ourselves.
                        your comment on this was not needed.
                        it seems like you like to get in the middle of things alot.
                        "play nice " " let others make choices "
                        who's playing wrong? Who had to say the above?

                        It was my choice not yours
                        By the way I was for the change in the format.
                        I keep my shop very clean and neat.

                        Rich

                        Comment


                        • #13
                          I sorta have a different opinion...If the moderator would mqderate this and leave a post explaining why after a few thousand times it would pay off. It happens on the other welding forums everyday
                          Another thing that causes it to happen is unless they changed it when you use the old address to the old forum you arrive here and it looks the same. If they changed that now then never mind.
                          So I guess you could say it is about 80% Millers fault.... IMO So come on guys lets get to moderating before this gets out of hand and we end up with 2 discussion forums!!!!!!!!!!!!!!!!!! (that would just be plain dumb)


                          As for the PCV...as some of you know last year I had a real job for a year or so.
                          Well in that shop they had pvc air lines. I have got to see first hand how they blow to ****!!! Just the sound scares the living crap out of you. And pieces will fly my friend.
                          I read a post somewhere about a severe eye injury from this and I believe it was from an ambulance driver it seems like if my memory serves me correctly.

                          Comment


                          • #14
                            I read a post somewhere about a severe eye injury from this and I believe it was from an ambulance driver it seems like if my memory serves me correctly.

                            i saw that one too.
                            my dad has PVC in his shop, been there for years no problem. i cant afford to do mine in copper yet so for not i just have standard air lines running from one shop to the other. from there its hooked to a reel with another 50" i think of roll out to cover the hold shop. some day i hope to get it hard lined, copper or the aluminum stuff they sell ready made for instillation would be my choice.

                            also be shore to leave a flexible link from the compressor to the start of the hard lines for vibration. i'll see if i can find a link to one if ya don't know where to get one.

                            Comment


                            • #15
                              Originally posted by DDCGuy View Post
                              You might want to check on the 2" x 3/8" reducer outlet fitting...

                              On my 60 gallon tank the reducer is straight pipe/o-ring sealed not the typical tapered pipe plug readly available at plumbing supply houses.

                              While you could attempt to "seat" a taper into the straight threads welded into the tank a drill/tap combination can make the reducer any thread size you wish and most likely would never leak!
                              Thanks for the heads up, I will have to look into it.

                              How would it be to run the 3/4" line but still have that 2x3/8" reducer off the tank?

                              Enough talk on the PVC, I already know I am going to run copper.

                              Comment

                              Working...
                              X
                              Special Offers: See the latest Miller deals and promotions.