Mainline on a 12 volt pump

[tonka]

I am looking to buy a few diaphragm pumps to install on the mainline, the pump I am looking at will run at 5.5 gpm, whats the max length of mainline can I have on that pump? also, there is another pump at 7 gpm, can the mainline be longer with the pump than the 5.5 gpm pump? My plan is to install 3 different pumps all on one mainline (2000' mainline, will be adding almost another 1000' to the top end, so 3000' in total, I'm dealing with a suddle slope).

[tonka]

Thought I would add the pump runs at 60 psi if anyone is wondering. Thanks!!!

[tonka]

So I have been crunching some numbers with my setup. I will have about 3000 feet of mainline and want to install a 12v pump every 750 feet or so.

Average season = 2 weeks/14 day
Gallons per tap/whole season = 20 gallons on vacuum
= 1.4 gallons per day per tap x 600 taps = 840 gallons per day
840 gpd / 8 hour day run = 105 gph
105 gph / 60min = 1.75 gpm

1.75 gpm of sap needing to be pumped out of the mainline, at the tank end, I would only need a 2 gpm pump to the least, 3 gpm pump should be a good pump for a little over kill. So I could have 2-3gpm on the bottom of the line with 2 2gpm pumps on the top end of the line.

I noticed in some of the videos I watched that guys are running about that 4 gpm pump (that I know of) and dealt with sputtering/chewing from the pump due to there not being enough sap in the line which would, from my understanding, loose inches in the tubing.

If you think my figuring is off please say something. I come to the conclusion that very few guys are monkeying around with this type of set up even on the small scale (50-150 taps).

[Super Sapper]

For one the psi doesn't mean anything unless you are pumping uphill. The gpm is determined by the volume of each stroke and the speed of the strokes. The higher the gpm the more volume it can move, both sap and gases (or air from leaks). The parameters to look at with these pumps is gpm and suction lift which is determined somewhat by how well the checks seat themselves.

[tonka]

If you get a pump with high gpm, like 5 or 7 gpm, will that increase the vacuum in the tubing?