"Existential Angst" wrote in message
...
"Zootal" wrote in message
. 97.131...
mike wrote in
:

On Feb 10, 4:14 pm, Zootal wrote:
Here is a somewhat more esoteric question. I have to snake around
some stuff, and I can do it with two 90 degree elbows, or two "45"
degree elbows. In the end, will using the 45 elbows give noticably
increased wat
er
flow? The pipe goes into a shower valve that is 1/2 inch, and the
interio
r
of the valve is even more restricted, so I'm thinking in this case it
won
't
make any difference.

But out there in the real world where we bend this way and that way,
does it matter how sharp the bend is wrt water volume?

Don't worry about it.

But I can tell you're an obsessive type, so if you want, you can look
up the equivalent friction loss of a 90 degree and 45 degree elbow
with regard to pipe diameters in a fluid dynamics book at the library
or on Google books if you don't believe me. From what I recall,
neither is significant, and you won't notice a difference.

Worry about low-flow shower heads instead.

I am cursed with curiosity for just about everything... ggg what if...?
what if ... ? what if ... ?

Proly not the biggest deal, but certainly two 45s are more elegant.
Slightly more expensive than one 90, but certainly more correct.
And the effect of pressure loss will be proportional to flow -- truly
insignificant with a low-flo shower head, perhaps noticeable in something
like a high-flo garden hose..
90s in air conditioning have a pretty substantial effect, and 45s would be
a good idea there.
--
EA


Personally, I always use a 45 degree elbow when I have a choice. For example
to change directions and elevations at the same location, such as when a
pipe is traveling parallel to and between joists and must make a 90 degree
turn and drop below the joists, I always use the 45 to angle down to below
the joist and then a 90 to turn across the bottom of the joist. If I am
going around something such as another pipe where one would need 4 90s to
get around the obstruction, I always use 4 45s to accomplish it, if the
obstruction is only slight, I will try to use "street" 45s to accomplish the
offset. To me it looks better, it does improve the water low and also
reduces noise at a high water flow.