mainline distance with vacuum?

[yards1520]

I need to run about 2,000' of mainline through a very flat woods. There will be about 5-600 taps on this line. I was planning on running 1"wet/dry line and getting a 30cfm pump because it is so flat with long distance. Does this sound sufficient to you guys? I am really nervous about getting sap out of this flat level woods.

[spencer11]

how flat are you talking? i heard mainlines should have a max of 2% slope to not cause turbulance, but could be wrong. you could use sap ladders or just tap really high at the end of the line.

spencer

[sapman]

If it's flat, any slope you can get is good. 1/2% isn't out of the question. Just have it super tight, with either lots of tiebacks or posts. But 2000', that is a LONG way!

[Sunday Rock Maple]

Go with 1 1/4" for the dry line.

[yards1520]

I know i can get a slight slope to it, but my main concern here is distance. I have read that my CFM's decrease significantly with distance so I am wondering if my 30CFM pump will be adequate or if I need a larger pump. The same with the line size. for 2000' should I use a larger size or does that just depend on #of taps only?

[Thompson's Tree Farm]

You will lose CFM in that distance. Having the wet dry will help that some and Sunday Rock is right, the 1 and 1/4 inch for dryline would be better. Having a larger wet line might help the slope issues too. I try to oversize lines in areas where slope is very limited. Look at it this way, if there is minimal slope (say 1% or less) the sap will drain out of the lines slower and a very slight dip (I know, my lines are perfectly tight and I never get any sags either:lol:) may cause slugging. Slightly bigger line may help avoid this problem and thus help get more CFM's to the far end of the line.

[sapman]

I had bad problems with pooling/sags even in 500'. 1" wet and 1.25" dry, both loaded up. 1.5" would even be prudent, given your distance, unless you really can get reasonable slope.

[Gary R]

Based on Cornell's chart's, no matter how much CFM you have at your pump, the 1" pipe will only flow 6CFM at 2000'. Cornell offers a tubing work book that will help producers size mainlines.

[Thad Blaisdell]

You wont need to run huge pipe the whole distance, It is possible that you could run 500' of 1.5/1.25 then 500' of 1.25/1 then go 1 inch for both the last 1000. take the first run right to the first group of mainlines, then reduce.... etc

[spud]

[QUOTE=Gary R;189898]Based on Cornell's chart's, no matter how much CFM you have at your pump, the 1" pipe will only flow 6CFM at 2000'. Cornell offers a tubing work book that will help producers size mainlines.

I read the same thing from Cornell just last night. If you have to go 2000 feet just to get to the woods then you should run 1 1/2 inch all the way. With a 30 CFM pump you will lose half of it just going the 2000 feet. Now you have to start running your 1 inch mainlines. If your mainlines are going to be 500 feet or so then your CFMs at the end of those lines will drop to 8-10 CFMs maybe. Your going to need all of that to get the max out of your trees.

Spud

[GeneralStark]

Everything you would ever need to know about setting up vacuum systems is contained in a Webinar and included documents (the workbook mention above by Gary R.) by Steve Childs of Cornell. If you follow this link: http://maple.dnr.cornell.edu/web/schedule.htm it will bring you to a schedule of webinars and the vacuum systems one is one of the first. Watch it and then download the workbook, do some simple math and you will have a design for a system that will produce. Why just wing it based on others' vague opinions?