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Copper fitting friction loss

Anyone have a friction loss chart for 1/4" ,5/16" , and 3/8" OD copper fittings and copper? I tried ASHRAE, Carrier, Mueller Brass Co., Cello Copper, DuPont, National Refrigerants, RSES, CDA( Copper Development Association ) Handbook," Facilities Piping Systems Handbook " by Michael Frankel and "Piping Practices for Refrigeration Applications" by Stanley Aglow, NOBODY , I MEAN NO ONE, NOBODY has charts for the smaller tubing sizes. Really? And 1/2"OD added 7-30-14 .


  • icesailoricesailor Member Posts: 7,265
    Friction Loss:

    I think that the reason is that those size ells aren't sold in short pattern 90's but in short or long patterned radius ells. Or you use a bender. They are refrigeration sizes and used for refrigeration. That the restriction from a radius'd bend is insignificant.

    Only Techno-Weenies like you and I would even dream up the question without an answer. Do they list resistance for copper tube made with lever bent copper tubing with the radius's made? Nothing looks more professional that lever bent copper tube. And its quicker and cheaper than using and brazing fittings. Except for the couplings of course.
  • TechmanTechman Member Posts: 2,144
    Friction losses

    Ice, guilty as charged ! They do have short and long ell's in the smaller tubing sizes. And knowing the resistance for the hand bender and for the slightly wider radius gear bender would be cool . Isn't this what  "they" do for a living? With linesets, there are an awful lot of places where tight ells are "required" by the  "make it look pretty rule"  and the LL has to be bent to physically match the SuctionLine  bend ,wheather or not its  a bend or a solderd/brazed ell. And then there are those that chose to use the 3rd radius ell, the dirty rotten "plumbers ell". So, on existing systems I get curious !
  • icesailoricesailor Member Posts: 7,265
    Bent into shape:

    When doing a replacement, just what do you do with all those short left over pieces of 3/8 OD copper tube back at the shop that are going to be sold for scrap. That you already charged for?  Is it worth more per pound as scrap or more by the foot in an install?

    The guy who replaced my system didn't do Shade Tree bends, but did a really neat job with brazed Refer 90's. Not having any of those old favorite tools, I would have loved to eliminate all those potential leak sources with nice lever bent 90's. Teach him how. Those bending springs are for DIY'ers or Pro's that use the Orange box as a supply house.

    If you ever have to run protected tube, oil (orange/red) or Gas (Yellow) in 3/8" OD, they bend perfectly in a 1/2" OD Ridgid lever bender.
  • TechmanTechman Member Posts: 2,144
    edited July 2014

    you know how to hurt a guy. I use bending springs on/off all the time. They have a drawer in my 4draw Solder/Braze tool box!!! Oh Man!  LOL!!!   For copper we charge for what we use, being 99% service/troubleshooting, that doesn't leave much room for installs. We also buy 50' rolls or 50' line sets, so any leftover copper is for sale on my next service call. I recover ANY/ALL pieces of copper that are just a little longer than the "make-up" of two fittings that are back to back, in all sizes. Most are capped/plugged! Much more profit on a sale as compared to scrap ,either dirty or clean !
  • RobGRobG Member Posts: 1,850

    I had to hook up an icemaker at my inlaws and went to the big orange store for some copper tubing. This stuff must have been type Z. I have never seen a peice of copper so thin. Needless to say, I stayed untill Monday and went to the supply house.

  • icesailoricesailor Member Posts: 7,265

    When I was a carpenter, I worked with this old grizzled guy who was really set in his ways. You never went anywhere without your hammer and a rule (wooden 6' folding types) He used to say that a carpenter without a hammer (or a ruler) is worse than a woman missing certain body parts. He also had a thing about cutting boards with a circular saw. The shoe of a circular saw always stayed on the board you were keeping, NOT on the board you wanted if it was short and going to fall. I learned that lesson so I didn't get the lecture. It had something to do with blade guards sticking and the shoe on the short piece and it falling off and the blade sticking, and sawing your leg.

    So if he saw you cutting a 12' board to 10'6", and you cut it from the short end with the shoe on the short end, he would jump up and down, take off his hat, throw it on the ground and stomp on it. Then berate you for it. Something about needing a 18" piece and leaving a 10'6" waste piece.

    Sort of like having a bucket full of left over usable pieces. Line them up on a floor and measure the total length of all the pieces. You'd be surprised at the value of that bucket as scrap. Which is far less than the valve as new and saleable pipe. But the straight hard or soft copper is like the board. If you need a 3' piece and you have a scrap piece that is 42" long, why would you cut 3' off a 50' roll? And have a 47' roll of tube and not know how long it was?

    As far as bending springs, you never know where you are when you bend them. If you can pipe with formed fittings, you can use a lever bender. You just have to use the old tried and true HABYM (Half **** Back Yard Mechanic) method. Take a short scrap piece and put it in the bender . Mark the 0* on the tube. Bend the tune to a 90* ell. Mark the 90* spot in the tube. Take out ell bent tube and save for future reference and measuring. You can take any and all measurements from the marks on the copper ell jig.
  • TechmanTechman Member Posts: 2,144
    Copper fittings

    See that? I had a mental wizzz.!Dam! I would like to add to the list of fittings that I have to find out what the friction loss is . And that is 1/2" OD copper.
  • TechmanTechman Member Posts: 2,144
    Friction loss.

    Hi SWEI, Thanks!. One of those sites starts at 1/2" nominal(ID) and the other starts at 3/8 nominal which is 1/2OD , but I think they are both good for good ole' H2O.Tks!
  • TechmanTechman Member Posts: 2,144
    edited August 2014
    American Standard to the rescue!

    American Standard has an Application Guide that has 1/4'' and up, it shows the Total Equivalent Length and for fitting losses it states " for smaller sizes, use 1/2" values".
  • icesailoricesailor Member Posts: 7,265
    Pressure Drop:

    If resistance is a form of pressure drop through a fitting, and you are using the pressure and temperature on a gauge to determine pressure drop, how do you compute pressure drop if it is heat loss/gain through the medium in the pipe? Cooling causes contraction which will decrease the pressure, and a rise in temperature gain will cause an increase. How can you determine the difference?

    If pipes increase as do their squares, and you have a 1/2" OD (38" ID) pipe, it takes four 1/2" ID pipes to equal a 3/4" ID pipe. Does the 3/8" ID pipe have 4 times the resistance as the 3/4" Pipe?

    I don't know. I'm just asking.
  • TechmanTechman Member Posts: 2,144
    Friction loss

    Just like hydronics, the fitting losses are converted to "feet" and added to the actual measured length of copper. 100' run and 75' for the fittings=175 Total Equiv Length, then compare to the "charts", uh oh ! that liquid line is supposed to be 1/2" , not the 3/8" that is in there. No wonder I have activity at the top of the riser and into the TXV!!
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