Water head, pressure, pipe diameter

100 feet of elevation will give you 43.31 pounds of pressure.
1 foot = .43 psi
just multiply feet of elevation cahng time .43 to get pressure you want

digitalmaster wrote:


Thank you. Is it really that simple? Seems to me even one of our cows
could have figured that out.

I can make it more complicated for you, if you like.  Pressure is force
per unit area, or the weight of water per unit area.  The volume of water
in a pipe is V=A*h, where A is the cross-sectional area and h is the
height.  The density is d, acceleration of gravity g, giving a weight of
W=A*h*d*g, and divide by A to get pressure, P=hdg.  But d and g are
physical constants, the only parameter that you can adjust is h.

So just say 0.43 psi per foot.

No regulator is necessary because the pressure is determined by the height
of the tank, and I assume the tank will have a predictable position.

Also, if the pipe is too skinny the pressure will drop when the water is
running because of the impedence of the line.  I don't know off-hand what
you'd get from a one inch ID.

If I were in cow country, I might be worried about drinking water that
had been filtered through cow poop.  I'll just have to trust that you know
what you're doing, but you might want to get the water tested for E. Coli
if you think it might be a problem.

--
"In any case, don't stress too much--cortisol inhibits muscular
hypertrophy. " -- Eric Dodd

Gregory L. Hansen wrote:
[snip]

E. Coli, cryptosporidia, giardia, the fun never ends. Plus, some
possible things that may be in the water require either boiling
or significant chemicals to get rid of.

They typical way that cattle country folk test the water goes
like so. They elect one of their group to try the water. They
don't *tell* him he's elected, just fill his canteen with the
at-hand liquid. If he remains of acceptable health, the water
is declared fit to drink.
Socks

Gregory L. Hansen wrote:



Great! My life is not nearly as complicated as it outta be. :-)


Okay, I will. :-) I have yet to look at the on-demand propane water
heater's specifications for water pressure to see what its tolerances
are, but at the moment I am considering locating the water source 120
feet above the outlet.


We will probably create our own flat area on the hill to bury the water
collection box (55 gallon drum), so the hill will not force us to pick
a site we don't want--- unless we hit a boulder. But then we also got
some dynamite.


Current water lines on the ranch are 1.5 diameter. I suppose the owners
of the ranch will want to keep the same diameter, since there are
already tools and spare parts for that size.


I have been force to drink such water when I hiked across the Mojave
Desert and then up the length of Death Valley (for fun; no, really).
Fortunately the water here is extremely clean: it comes out of rocks
and flows into a concrete tank at the spring; the spring and tank are
covered with plastic sheeting, plywood, and rocks. Two of the three
humans who live here have been drinking it for 11 years.

For 40 years that water used to be transported down to the ranch via
cedar logs that had been carved into troughs like a flue; 30 years ago
that flue was replaced with hose.

There is another good spring down the canyon a mile that was once flued
down to the canyon floor (well, a bench 30 feet above the canyon floor)
around 70 years ago. It is located at the base of a cliff wall that
rises 1,700 feet. I climb up there now and then to get a drink. :-)

The propane on-demand heater I've got works with 18' of head
fed through a 3/4" garden hose, but not with 16'.    I know
this because the 55-gal barrel sits on a 16' tower, and
the heater doesn't work when the barrel's less than half full.

1. 100 feet of elevation difference.

2. No

3. No

I presume you will use the barrel as a reservoir with overflow of the excess
water.
Pipe size depend on the horizontal distance and the desired rate of flow.
This data is missing.

SJF

I did this kinda thing for my mom, back in 1976... geez how time
flies:(

Anyhow with a similiar drop and using garden hose we were able to run a
sprinkler the kind that goes left and right, for a long time.

in my moms case she had a cistern on the hill, for their home.

I tapped the overflow to a old hot water tank so she could water her
garden withourt concern about depleting the water for her house. It
worked great till my moved back here and got diovorced.

odd how something that long ago applies here today

hallerb@aol.com wrote:


Yeah, damn few of us are getting younger as the days fly by. :-)


Hummm. I was thinking of a second tank at the cabin but the demand for
water probably will not be that great.

Thank you for the reply--- I have added it to my notes to tell the
ranch owners.

SJF wrote:



Thank you. Your answer matched the other reply. Hummm. Why did I not
know the answer? 100 feet of head is 100 feet of head, after all. It
does not seem it could be that simple.


The greatest demand at the cabin will probably be a shower: about 5
gallons a minute at most. Since the hill's incline is about 20 degrees,
I can probably use a sine table to find distance. Angle "A" is 20
degrees and side "a" is 100 feet. Makes me wish I finished high school.
:-) Horizontal distance at the moment is unknown because I do not know
how far away, climbing the hill, will be 100 feet high.

Thank you for your answers. Since the answer to query #2 appears to be
"No," then we can err on the side of too high.

desertphile@hotmail.com wrote:

   ...


The distance that matters is the length of the pipe. One elbow or globe
valve has about as much pressure drop as maybe eight feet of straight
pipe. Use 3/4, or, to be generous, 1". (Generous means you won't mind
someone flushing the toilet while you're taking a shower.)

Jerry
--
Engineering is the art of making what you want from things you can get.
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯

Sorry!  I hastily misread your question 2.  The answer is YES.  If you put
the collector higher than 100 feet, the static pressure will be more than 43
psi.

That's a pretty steep hill at 20 degrees.  Or did you mean 20 percent grade?
A slope of 20 degrees means the minimum length of your supply line to the
house will be 300 feet.  For a 20 percent slope, it would be 500 feet.  You
will probably need something to counter water hammer when you shut off the
flow.

SJF

This is a ranch, man.  If there is water hammer, they'll hammer back.
    8-)

Remove NOPSAM to email me.  Please let
me know if you have posted also.

mm wrote:



Ranch, shmanch. If there's a serious water hammer it can blow a fitting
off the pipe. There's more than 300 lb of water in 400' of 1.5" pipe.
How fast do you think you can stop it without breaking something?

Stretch in the pipe wall helps considerably. With polyethylene pipe, t
can reduce the peak pressure to one quarter, down from the 1000 psi that
steel pipe might generate.

There's 37.5 gallons in out hypothetical 400' run of 1.5" pipe, weighing
about 300 lb. At 5 gpm, it flows at 100 fpm, or 17 ft/sec or over 5 mph.
If you slam a 300lb weight into a cinder-block wall at 5 miles an hour,
would you bet that the wall stands? I wouldn't!

Jerry
--
Engineering is the art of making what you want from things you can get.
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯

Jerry Avins wrote:

There shouldn't be any more problem of water hammer with that set up
than with a standard system with long runs of pipe.  I was on a
community well system (40-60 psi) with a 1/4 mile run to the well for
me.  Never had a hammer.  No difference in flow in the pipe or dynamics
of possible water hammer if the pipe is horizontal or vertical, the
flow is the same.

Harry K

¯AF¯AF¯AF¯AF¯AF¯AF¯AF¯AF¯AF¯AF¯AF

Jerry Avins wrote:

There shouldn't be any more problem of water hammer with that set up
than with a standard system with long runs of pipe.  I was on a
community well system (40-60 psi) with a 1/4 mile run to the well for
me.  Never had a hammer.  No difference in flow in the pipe or dynamics
of possible water hammer if the pipe is horizontal or vertical, the
flow is the same.

Harry K
 ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯

Actually, in your case, it is the distance from your house to the water main
that determines the water hammer.  Not the total distance to the supply
source.  The OP is dealing with a single long pipe which will create a
problem unlike the usual suburban situation.

SJF

SJF wrote:

¯AF¯AF¯AF¯AF¯AF¯AF¯AF¯AF¯AF¯AF¯AF

That was my distance to the system, 1/4 mile of pipe between my house
and the well, no other connections.

Harry K

Harry K wrote:

   ...


Is there anything else between the house and the well? A pump and
storage tank, maybe? At my place, the pump is at the bottom of the well
and the pressure tank in the house. No possibility of hammer there.

Jerry
--
Engineering is the art of making what you want from things you can get.
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯

Jerry Avins wrote:

Pressure tank (huge) at the well head.  That system used to serve 4
houses.  I finally drilled my own to get off of it as I wound up the de
facto non paid maintenance man.

Harry K