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View Full Version : A question of fittings and head


Molehs
01/26/2012, 10:26 AM
If I were to put 1 1/4" fittings at the bends (90's) of a run of 1" pipe would that significantly reduce overall head?

Utah Fatman
01/26/2012, 10:48 AM
You are putting 1.25 inch elbows on 1 inch line? If so, yes, every bend or length of pipe adds friction loss to the head. Oversizing them can help some but the turbulence caused by a 90 degree bend is amazing to see. I used to have a chart but probably can't find it. If the loss is significant depends on your requirements and how close you are to maxing them out. If you have margin to accept the slight loss and you need to put the elbows in then you have to accept the slight loss of head. The bigger the pipe, the larger the acceptable rate of flow at the same velocity and the the bigger the pipe at the same rate of flow the less friction loss.

Molehs
01/26/2012, 11:02 AM
Cool, thanks. I'm still theory crafting a HOB closed loop in my head for a spring/summer project. Trying to maximize the potential of the pump. So if spending a tiny bit extra on elbows/adapters means preventing head in a noticeable amount, then that's what I will plan. I will use flexible PVC and 45's everywhere I can but 90's are inevitable.

der_wille_zur_macht
01/26/2012, 12:37 PM
Given that goal, why not just use 1 1/4" everywhere? It'll probably be cheaper and will definitely be easier since you're not bushing up and down at every single elbow.

Molehs
01/26/2012, 12:43 PM
Given that goal, why not just use 1 1/4" everywhere? It'll probably be cheaper and will definitely be easier since you're not bushing up and down at every single elbow.

:headwally:Logic has no place here!:beer:

Utah Fatman
01/26/2012, 01:15 PM
I would agree, my irrigation background helps with this plumbing problem. 1.25 inches used to be common, but since the cost of 1.5 inch is just a bit more most are going to that for the increased flow. If you run build 1.25 inches throughout it will probably be near the same cost as doing 1 inch with 1.25 elbows and bushings. If you want a higher flow 1.5 is easier to find than 1.25 and gives a great deal of added flow to your system.