Thanks for the response. I was concerned about the 10,000 rpm on the SQ. I'm going to need more help in figuring all this out. Here is my situation:
The well is used exclusively to water a 4-acre vineyard divided into 5 blocks of 500 vines each. I need ~12 gal/min to provide water to each vine some of which are 10-50 feet above the level of the well. The 2 hp pump sits at 85 feet in a 200 foot 8" inch well that was drilled in 1975. I have the well log and it tested at 50 gal/min at 100 feet. It is a simple system controlled by a standard pressure gauge set at 55 to 75 psi and uses a 350 well-x-trol pressure tank. I believe the pump is undersized because most of the time it runs constantly when a valve opens. Not sure if that is a problem or not. I use 1 gal/hour pressure compensating emitters which work well. Historically, pumps in this well fail after about 10 years due, I think, to 3ppm iron in the water. The pump is starting to go bad and I want to replace it before the growing season, my thinking was I could upgrade the system in the process. I got a bid from a local pump installer for a more robust pump and he recommended a 3-phase motor. Here is the upgrade proposal:
--35-GPM at 50-PSI with a 30ft elevation lift above the top of the well and a 140Ft pumping level down the well
--Gould 35GS30 3 HP 3-phase
--3HP VFD control panel with transducer
I'm not about to go with this proposal as I have doubts about three-phase and this was a very expensive bid.
Because of the complexity of the irrigation system (11/2" supply pipe with a bit of 1" and many hundreds of feet of 5/8" irrigation tubing), I don't have a good idea of pressure loss to friction. Not sure how to figure that out.
My thinking at the moment is to go with the Grundfos SP series with something close to what I have. If it ain't broke don't fix it. But any thoughts about an upgrade would be greatly appreciated.
In a related problem, I use a Mazzie venturi to fertigate the vines. It works perfectly for the two acres that are at well level but will not operate for the hillside grapes. When pumping that 10 to 50 feet higher there is no pressure differential at the venturi. I'm looking into installing a small booster pump before the injection point.