"Rodney Pont" wrote in message
news:atcfzvasbuvgflfgrzfygqhx.i06dgd0.pminews@ihs1 ...
On Thu, 01 Jul 2004 02:24:56 GMT, Grubber wrote:


http://www.aquaticeco.com/index.cfm/...Detail/ttid/54

Anyone interested should see the chart on that page since you need to
know flow rate and effective pipe length and its diameter.

There is another friction loss chart here
http://www.plumbingsupply.com/flowchart.html that goes up to 500GPM and
5" pipe, it also has the pipe length to add for various types of
fittings.

Flex PVC - no turns

Flex PVC has turns even when you're trying to keep it straight :-)

I did a little experiment with flex PVC compared to solid waste pipe.
The pump was an Otter Maximus 9000 with 8 foot of pipe and two 90
degree bends to a head of 2 foot 6 inches.

I tried with 1 1/2" flex PVC, good quality thick pipe with very little
ribbing visible inside the pipe, and two gentle 90 degree curves. The
waste pipe was push fit 1 1/2" with two 90 degree bends.

I timed the flow into a 2 gallon bucket, flex pvc first then solid
waste pipe and the waste pipe allowed 40% more water to flow than with
the flex pipe. I can't remember the flow rate now but I do remember the
40%.

I also have some of the cheaper flex pipe that is far more ribbed
inside than the type I used but I only have 4 foot of it spare do
didn't try with that and it would have been worse anyway.

I was really surprised by the huge difference the small amount of
ribbing made to the water flow and will always use solid waste pipe
where I can.

--
Regards - Rodney Pont
The from address exists but is mostly dumped,
please send any emails to the address below
e-mail ngpsm4 (at) infohitsystems (dot) ltd (dot) uk



OK, you guys just about had me convinced that my pump wasn't flowing at all
so I did a test. I turned off the pump, bailed 20 five gallon buckets out
of the settling pool the pump spills into and timed how long it took to fill
back up (134 seconds). Based on that, it's doing ~2685 GPH. Works for me.

As for the 'turns', there's about 150 degrees worth of gradual bend over the
75' of 2" pipe. No UV, no filter, just a strainer on the intake to keep
fish out of the pipe.

Based on the charts, 1.5" pipe has about 3.4 times as much resistance as 2"
pipe. Also, this pipe is so stiff I don't think I could do 2 90 degree
turns in 8 feet. An 8 foot semi-circle, sure. Maybe we're talking about a
different kind of pipe.