----- Original Message -----
From: <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Wednesday, May 01, 2002 5:10 AM
Subject: Re: First Tea Analysis Results
>
> In a message dated 4/30/02 10:56:08 AM, [EMAIL PROTECTED] writes:
>
> << I think I'm losing interest in the flow forms idea because it
> involves pumping the biologicals. I think I'm going to stick with
> 'small bubble aeration >>
>
> I am working on (in my head) a flow form that will work through an
upweeling
> tube...SStorch
>
> Hi Steve and Allan
Maybe you can help me. I am having
trouble coming to grips with the controversy surrounding pumps - several
questions arise
1. Diaphragm pumps are more softer than rotary types ?? I have used a hardie
dia pump on a couple of field sprayers. The forces inside these things would
be pretty incredible - the whole water column smashes to a stop and then
accellerates to full velocity 700 times a minute - incredible velocity of
the fluid through the restriction of the valve bodies - and if you dont run
a air filled pressure compensating bladder to soften the hammer effect the
whole system will eventually self destruct - blow pipes - wreck the innards
of regulator valves etc. BUT they dont rotate the water (more later)
2 . Given all of the above and that we dont require high pressure how much
worse is a slow running centrifugal pump? Has anyone seen data that compares
the peak velocity of either system ? Or has this all been a case of doing it
by feel (nothing wrong with that) 3. All of the rotary pumps that I have
seen lately rotate the water in an anti clockwise direction which is wrong
and detrimental for you guys but good and beneficial for us south of the
equator.
4. Has anybody your side of the centreline seen and/or tried a rotary pump
that puts a clockwise spin on the water as it goes through?
Old centifugal pumps are a dime a dozen and cheap to maintain where a
diaphragm pump good enough to feed a set of flow forms is a very pricey
item.
Any other thoughts would be appreciated
Cheers
Lloyd Charles
