Why do I want a continuous Safe Vacuum pump? I want one in order to move air through the processor as well as create a minimum -10 hg vacuum. I can already do this with the car Evacuation AC vacuum pump rated at 2.5 CFM but the pump tends to overheat, and well that is bad for so many reasons. So, I think I have a solution for a safe continuous vacuum pump that moves 2-3 CFM, but I need some help. Specifically about understanding PSI, Head, and GPM with pumps.


Clearly Venturi's work at making a vacuum. I have even plumbed a water Venturi/Vacuum system like I am describing below with a HF pump and a small Mazzei Venturi (584) and was able to pull -22 hg with it. However, it basically was moving only a small CFM, so any air added was overwhelming the vacuum system.


The Design:
Basically if you took a 5 gallon bucket, filled it with water and put a Submersible Water Pump like this one, which basically moves water at a tad under 60 gpm and unknown PSI and couple it with a Mazzei Injector of 1.5" (Model 1584) and use the tables listed HERE and look at page # 9 (Green Air Suction pages 5-50 psi --- the first column for 1584 injectors) you get at 40 PSI inlet, 51 gpm, lets say 5 PSI on the outlet (although that is all friction I am guessing) you get 188.7 Standard Cubic Feet per hour which I am guessing (again) is 3 CFM.

This would allow you to have a continuous vacuum, safe because the vacuum is created by water so the worse that could happen is that you get a slight bit of methanol in that water, and relatively inexpensive set up ~ $120.


The questions that still remain:

1. What PSI do these pumps create?
2. Can they be run continuously in 5 gallon buckets? Will that be enough water to dissipate the heat. (I do have a 15 gallon barrel I could cut the top off.)
3. In my arrogance, everything else I do don't understand or am missing.

Thanks
Doug

PS. Oh why only -10 hg Vacuum and not a full -25? Because more or less about -15 hg, my processor pump stops getting a good flow to its inlet side.