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Glenn Ashmore
 
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Default watermaker pump questions

You can do that with a AX or B size belt. The AX might be better
because it is easier to get pulleys in that size. Both are available
from Grainger and most industrial suppliers. They are both rated a
little over 2.5 HP on a 2.5" drive pulley @3450 RPM. A 2 HP AC motor is
going to eat a lot of power though. You will need better than 3K watts
to crank it up and 1,500 to keep it running. That is why I decided to
go with engine drive.

Carl wrote:
How about building a watermaker with an existing 2 hp 3450 motor I
already have. With a 2.5" dia pulley on the motor - would need 7"
pulley on the pump to get 1330 rpm at the pump.

What about power transmission and longevity - some sort of toothed
pulley / belt - like a timing belt?



On Thu, 01 Jul 2004 21:50:39 -0400, Glenn Ashmore
wrote:


The Cat 280 is a 3 frame pistom pump with 304 valves and chrome plated
brass pistons. It can be ordered with chrome plated brass or 304
manifolds but it is the valves, pistons and cylinder walls that pit
first. A 3 frame plunger with an all stainless top end like the 241
would be a better choice but the 280 optput is just about right for an
18-20 GPH RO system at 3 GPM @ 800 psi and 1330 RPM. It can be direct
or belt driven. If you keep it running every day or so and flush it
with fresh water it should last a fairly long time. If you don't flush
it after every use it will not last very long. Still, it is half the
price of all bronze, 1/3 the price of a full stainless model and you can
rebuild the whole top end for under $200. Just don't plan on rebuilding
it on Bora Bora.

Hank wrote:

I've seen some watermaker pump questions here in the past - where's
the DIY watermaker expert - here's another.

I can get a good price on a new CAT 280 pump - 3 gpm at 1000 psi.

Cylinder and sleeve wear surfaces are hard chrome plated 304 stainless
steel - 304 Stainless steel discharge valves for wear resistance.

Prev thoughts were that either 316 SS or Bronze were or for
watermakers - how about the 280?





--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
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