Announcement

Collapse
No announcement yet.

Air compressor piping

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • #31
    If you want to build a cooler try 3/4" alum fin radiant heating pipe. The stuf you use to heat your house. When I worked for a compressor shop we built several of these. Just build something like a car radiator and put it in front of a fan. Ours was mounted in the exhaust fan for the shop area. Cooled the shop and the shop air.

    Comment


    • #32
      Heres this if it will help. http://www.1969supersport.com/draw1.html

      I also have a link to a 12 page discussion on air lines and compressors on my web site if your interested, also some stuff on negative pressure and supplied air respirators.

      Rob

      __________________
      "There are questions to be answered, and answers to be questioned"


      Jigs, sandblasting, shop, paintroom, rotisserie, pictures, little bit of everything.
      http://www.1969supersport.com
      Last edited by rubadub; 03-05-2008, 07:23 PM.

      Comment


      • #33
        In a small shop 1/2 line is plenty and no need for anything larger than 3/4. Most places have one thing running at a time. Simple is good, I have extra piping but really only 5 places I use air, Menard's has one of those tool time kits, regulator, filter, all 1/2 ports under 50$, I threw the oiler away.
        Attached Files
        Last edited by Sberry; 03-06-2008, 04:02 PM.

        Comment


        • #34
          Wrong post forum

          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'll have to agree. I wander all over these forums. I jump in when I feel like it. I don't care where it is. I suppose the moderator can move the post to the correct area (if necessary). I thought that what a moderator was for.
          Thanks, BH

          Comment


          • #35
            the moderator can move the post to the correct area (if necessary). I thought that what a moderator was for.
            Thanks, BH

            the true Miller moderators prefer to let the board run its self without too much interference. if fighting starts they warn then suspend members as needed. moving posts is not that big a deal and not enough moderators to keep up with them all.
            the few member moderators like myself only step in for excessive profanity, nudi ty, and spam. beyond that we leave members posts for miller to handle.
            we all just need to let things slide once in a wile and every one will be happy and get along......tall order, i know.
            thanks for the help
            ......or..........
            hope i helped
            sigpic
            feel free to shoot me an e-mail direct i have time to chat. james@newyorkmetalart.com
            summer is here, plant a tree. if you don't have space or time to plant one sponsor some one else to plant one for you. a tree is an investment in our planet, help it out.
            JAMES

            Comment


            • #36
              Originally posted by eyecandy View Post
              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.
              If you stay with the 2x3/8 reducer at the tank your SYSTEM will only flow to the flow potential of the 3/8 reducer. It will not matter how large your downstream piping is.
              Change the reducer to a 2x "whatever size piping" you are going to use.

              Griff

              Comment


              • #37
                The fitting on the tank will still frow more cfm then the compressor can put out, changing the fitting will not hurt anything, but I don't think you will see any benifit.
                The larger downstream piping will act as a receiver storage tank.

                I have a similair type compressor, Cambell Halsfield, I will diffinantly build an air system in the new shop (I actually have two of these compressors and will run them in tandom when needed), but for the past 4 years I have just used a 3/8 hose.

                I run a 3/8 hose from tank , through the filters to the work 3/8 hose. The sandblast cabinet sucks the compressor down in about six minutes.
                Not the ideal setup but I use it this way almost everyday.
                Tim Beeker,
                T-N-J Industries
                (my side bussiness)

                Miller Synchrowave 350LX with tigrunner
                Esab 450i with wire feeder
                HH135 mig
                Thermal Dynamics cutmaster 51 plasma cutter
                Miller aircrafter 330 - sold
                Marathon 315mm coldsaw
                vertical and horizontal band saws
                table saw
                Dewalt cut off saw
                Sand blast cabinet
                lots of hand grinders
                Harris torch
                beer fridge

                Comment


                • #38
                  Originally posted by tnjind View Post
                  The fitting on the tank will still frow more cfm then the compressor can put out, changing the fitting will not hurt anything, but I don't think you will see any benifit.
                  The larger downstream piping will act as a receiver storage tank.

                  I have a similair type compressor, Cambell Halsfield, I will diffinantly build an air system in the new shop (I actually have two of these compressors and will run them in tandom when needed), but for the past 4 years I have just used a 3/8 hose.

                  I run a 3/8 hose from tank , through the filters to the work 3/8 hose. The sandblast cabinet sucks the compressor down in about six minutes.
                  Not the ideal setup but I use it this way almost everyday.
                  Not a very big compressor if it cannot fill a 3/8" hole.

                  Griff

                  Comment


                  • #39
                    Nope, just like the OP has.

                    That is why I think a larger fitting is unnecassary.
                    Tim Beeker,
                    T-N-J Industries
                    (my side bussiness)

                    Miller Synchrowave 350LX with tigrunner
                    Esab 450i with wire feeder
                    HH135 mig
                    Thermal Dynamics cutmaster 51 plasma cutter
                    Miller aircrafter 330 - sold
                    Marathon 315mm coldsaw
                    vertical and horizontal band saws
                    table saw
                    Dewalt cut off saw
                    Sand blast cabinet
                    lots of hand grinders
                    Harris torch
                    beer fridge

                    Comment


                    • #40
                      not so simple...

                      Short restrictions in air supply piping do not act as predictably as one may think. The smaller nipple may not play a role under most circumstances. The air is compressed and then finds the pressure/volume on the other side of the restriction until the point that the "choke flow" ratio is reached.

                      Choke flow calculations are fairly deep into calculus and I certainly am not an expert. What it boils down to is that the pressurre on the downstream side of the restriction would need to be almost half of the supply side before there would be any restrictive effect. I do not think you will experience any problem unless you plan on running multiple high air volume consumption tools at the same time, like a DA and a plasma cutter or impact. You just would not normally use the air fast enough for that to act as a restriction.

                      That is why most smaller compressors only have a 3/8 outlet.

                      Of course, to gain the greatest volume and delivery regardless of how quickly the air is consumed, opt for the largest fittings. Easier than trying to do the calculus

                      I just wanted to point out that some minor restriction may be irrelavant based on the actual use of the system.

                      Thanks,
                      John

                      Thunderbolt AC/DC
                      MM 175
                      Maxstar 150 STL
                      Blue Star 185 DX
                      Spectrum 375

                      Comment


                      • #41
                        Originally posted by Handy560 View Post
                        Short restrictions in air supply piping do not act as predictably as one may think. The smaller nipple may not play a role under most circumstances. The air is compressed and then finds the pressure/volume on the other side of the restriction until the point that the "choke flow" ratio is reached.

                        Choke flow calculations are fairly deep into calculus and I certainly am not an expert. What it boils down to is that the pressurre on the downstream side of the restriction would need to be almost half of the supply side before there would be any restrictive effect. I do not think you will experience any problem unless you plan on running multiple high air volume consumption tools at the same time, like a DA and a plasma cutter or impact. You just would not normally use the air fast enough for that to act as a restriction.

                        That is why most smaller compressors only have a 3/8 outlet.

                        Of course, to gain the greatest volume and delivery regardless of how quickly the air is consumed, opt for the largest fittings. Easier than trying to do the calculus

                        I just wanted to point out that some minor restriction may be irrelavant based on the actual use of the system.

                        Thanks,
                        Incorrect. Once a line is restricted the system cannot pass more air than what can pass through the restriction. Period. No calculus needed.
                        In this case the 3/8 orifice may or may not impact this gentleman's useage but it will restrict the system's potential.
                        Griff

                        Comment


                        • #42
                          Hmmm?

                          Well, then really we agree.

                          The restriction can ultimately limit the amount of air volume.

                          The fitting may or may not be a factor depending on the use.

                          The easiest way to avoid being marginal is not to use restrictive fittings.

                          The fitting may limit the systems potential.

                          But my point was that in a compressed air system the physics are more complicated and a small restriction may be inconsequential to his use.

                          The restriction only comes into play when you can use enough volume to reach the point of choke flow.

                          This is a link to an engineering book on hydraulic and compressed air piping systems. The pertinent section is between pages 293 and again on 297 where this book mark is.

                          Note the section on "choke flow" and the related calculations.

                          http://books.google.com/books?id=H5w...l=en#PPA293,M1

                          This is not as simple as a restrictor in a shower head.

                          Makes for boring reading but if someone is interested there it is...
                          John

                          Thunderbolt AC/DC
                          MM 175
                          Maxstar 150 STL
                          Blue Star 185 DX
                          Spectrum 375

                          Comment


                          • #43
                            Originally posted by Handy560 View Post
                            Well, then really we agree.

                            The restriction can ultimately limit the amount of air volume.

                            The fitting may or may not be a factor depending on the use.

                            The easiest way to avoid being marginal is not to use restrictive fittings.

                            The fitting may limit the systems potential.

                            But my point was that in a compressed air system the physics are more complicated and a small restriction may be inconsequential to his use.

                            The restriction only comes into play when you can use enough volume to reach the point of choke flow.

                            This is a link to an engineering book on hydraulic and compressed air piping systems. The pertinent section is between pages 293 and again on 297 where this book mark is.

                            Note the section on "choke flow" and the related calculations.

                            http://books.google.com/books?id=H5w...l=en#PPA293,M1

                            This is not as simple as a restrictor in a shower head.

                            Makes for boring reading but if someone is interested there it is...
                            I was not referring to a shower head.

                            Comment


                            • #44
                              It is my understanding that the restriction is a function of diameter and length. especially where gases are concerned. I'm no expert but i'm pretty sure if you plumbed with the same diameter tubing as the restriction you would see a great drop in airflow. I have an engineer friend who has dealt with gas flow extensively, i believe he is the one who told me this but the conversation probably happend 10+ years ago. I'l run it by him.
                              Dynasty 200 DX
                              Millermatic 175
                              Spectrum 375
                              All kinds of Smith OA gear

                              Comment


                              • #45
                                Sorry, no offense

                                In this case the issue is one of a fitting creating an orifice as the restriction; a fitting on the 60 gallon tank. If you were to reduce the entire length of the remaining supply pipe you would restrict the volume based basically on the same flow rate calculation which would be a function of the pressure 1, restriction size or pipe size, pipe resistance per length (rough/smooth) and the pressure 2 on the end of the pipe, i.e. atmosphere, other back pressure or vacuum. Each fitting, elbow, tee, etc. has a calculated resistance which is added as a function of feet of resistance. There are even more variables, such as heat loss, temperature of the gas, moisture etc.

                                My recollection, and it has been some years is that increasing pressure1, the source, will continue to increase the velocity and volume of gas until the speed of the gas becomes sonic, at which point you reached choke flow.

                                In other words when the P2 (your pipe/hoses system) reaches approximately half of P1 (your tank/compressor) the air moves so quickly across the orifice or restriction that it goes from subsonic to sonic and at that point no additional volume of air can pass.

                                Keep in mind that when the pneumatic system is in use these variables are not constants, the compressor kicks on, other users use air etc. The other less apparent variable is the size of the system after the restriction. When the system is static, both sides of the restriction reach equilibrium. As soon as you begin to use the air, the volume on the user side decreases reducing the pressure on that side and the air from the source rushes in (through the restriction) to replace the void seeking equilibrium. As long as the ratio of P2 pressure to P1 pressure is above the choke flow point and the air moving across the restriction is subsonic, the volume to the user/device remains the same. If the compressor doesn't kick on eventually the pressure will dwindle, if the compressor is running and it constantly can provide P1 pressure sufficient to maintain the volume the flow remains the same. You can see that there would be many possible variables based on your specific use and number of users. If the system then has a large volume (lots of large piping or a tank after the restriction) when the air begins being used the proportion of volume depleted is less (slower pressure drop) on the user side of the restriction so the chance of P2 falling quickly enough to choke the flow is diminished.

                                I only wanted to raise this point because it is easily misunderstood, not to be offensive. My point about the shower head is that there are different dynamics in a fluid system when you add a restriction because of the compressibility of gases.

                                My physics is limited to a high school class and it was mannnnnny years ago and this is my best recollection. I would be interested in someone who is an engineer to chiming in. Maybe i'm off base... OK, shoot me!

                                Thanks
                                Last edited by Handy560; 03-19-2008, 11:35 AM. Reason: cause I cAn'T tYpE
                                John

                                Thunderbolt AC/DC
                                MM 175
                                Maxstar 150 STL
                                Blue Star 185 DX
                                Spectrum 375

                                Comment

                                Working...
                                X