Vacuum Boosters - Part 2

[ennismaple]

With the help of Kevin (Maple Hill Sugarhouse) I've made my first vacuum booster. It's got 2 incoming and 1 outgoing 1" lines and a 1" dryline connection on top. I'm leaning towards a 1-1/4" dryline but haven't made up my mind yet. I didn't add any valves or pressure gauges to it yet. I got everything from Home Depot for about $30 Cdn.

While trying to sell the idea to my father he asked if the vacuum at the booster will work against the vacuum downstream of it. I see his point. The vacuum at the booster will be around 15" Hg and on the mainline downstream of it may only be 8"-10". In my mind, the sap will want to flow back uphill towards the booster instead of towards the tank due to the pressure differential. FYI - The mainline where I plan to install it is fairly flat.

Am I missing something or does the Old Man have a point? Any comments would be appreciated.

Martin

[maplwrks]

Martin,
Why would it be different? If both lines go directly to your releaser, the vacuum will be the same. The only thing that would cause the vacuum to drop in your wet line would be leaks. Keep all connections good and tight and you won't have a problem.

[brookledge]

You shouldn't have that much of a difference. What happens is that the wet line has a tendency to fully fill the diameter of the pipe especially if you have a flatter slope or a good run. The liquid can't travel as fast as the air so when this happens you begin to get turbulance and you lose vacuum capacity up the line. With the booster utilizing the dry line what you are acomplishing is to allow the air to get out into the bush without interference
I do not think you will ever have enough of a vacuum difference to pull the sap back up hill on your wet line.
You will definately see an increase in efficiency.
Keith

[ennismaple]

Thanks for the explanations! It makes more sense to me when you call it a vacuum equalizer. The highest vacuum is still at the releaser and if the mainlines are all flowing downhill then the sap will end up where it belongs.

We've got another section of mainline that's probably 25 years old (or more) that we intend to replace. It's still air tight but I can't imagine it being anywhere near as clean as it should be. What I want to do is use it as a dryline by replacing all the cut-in manifolds with unions and putting a booster about halfway out.

I hope we need to buy a bigger tank...

[Parker]

I use Kevins type of booster too,,I would like to find a way to see inside my boosters,,like the Lapeirre boosters,,I saw a few opperators that were using the LaPeirre boosters and it was helpful to see inside the booster (especially where it was being used for a manifold,,5-6 lateral mainlines into the 2-2" mainelines) made it so you couls really see what was happening in there..,,,,any ideas? do they make clear PVC?

[emericksmaple]

Parker, He is an idea that I am going to try. Ever look in the leader catalog and see the boosters they have. it just looks like a piece of pvc pipe on it's side with two pieces of thick plexyglass on the end for covers. I am going to try to bulid a couple of these the summer for the new system we are putting in. When we was up in Canada this spring visiting friends during season i saw one of these, I don't like them as good as the upright ones but I do think they would be easier to make to be able to look inside of one.

[saphead]

McMaster-Carr carries a full line of clear PVC.A couple of elbows ,a tee,some short nips and socket/fnpt fittings for the elbows and voila, a vacuum transfer device with optical observation! I would also add a couple of valves and a vacuum gauge for quick leak detection.

[Maple Hill Sugarhouse]

post edited

[maplecrest]

i build my manifolds out of 1and1/2 inch black plastic pipe stand up with dry on top, wet at bottom with the main lines in between. i put one every 1000ft. or where every 3/4 or 1 inch line comes to main lines of wet and dry. then i use clear milk hose to hook line to manfold with vac gauge and valve for trouble shooting. if you see sap ripping thru milk hose you know that you have an air leak up that line. makes finding problems, like lost vac quick when you can see each line going in. i can see it from a distance with out having to go right up too it. same idea as the loops you use to hook lateral lines to main lines. you see sap shooting thru loop you know you have a vac leak up that line. loose spout,broken tee ect. i have seen pvc manifolds but expensive to make. mine are still 30 plus dollars , depends on number of lines comming in and valve type, vac gauge ect. i have one wet line that is 1 and 1/4 with dry line 1and1/2 that is 1and 1/2 mile long with the vac loss of 2 on a full flow day if no moose or wind storms come thru like this year.i have 8 manifolds on that system. jeff

[danno]

Trying to figure out this dry line thing. Can I tie the same dry line into the same wet line in a few locations as I move up the bush? I have several sections of maple all tied into the same mainline as it works it way down the hillside.

I was going to tie a dry line booster into the wet line just below where I begin pick up my first taps (about 1000 feet from the releaser). Can I than continue the same dry line up to the next section of taps (another 500 feet) and tie it back into the same wet mainline again?

[Maple Hill Sugarhouse]

post edited

[maplecrest]

Danno- Yes you can T off the first booster and then keep running a dry line to the 2nd or more boosters if you would like. Danno, If you have lines of 3/4 inch teeing into an inch or 3/4 that is where i put a manifold i tee into the wet line and into the dry line and run the lat. line in the center adding vac to the line that is tieing in. i put a manifold on each one or every 1000 feet jeff