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Fox Run
02-25-2014, 10:40 AM
What sthe size of tubing need for running a dry vacum line. We are lookng into putting in a whipping dry vac system and i've heard for dry vac line, it needs to be one tubing size larger than the vacum line? We are running 1000ft of 1 1/2" then reduced down to 1'' for the next 2000ft for our main line, with 3/4'' lateral lines Tee-ing off from it. Any help would be appreciated.

maple flats
02-25-2014, 12:28 PM
2000' of 1" is too long if it is 1 piece. You won't get vac. that far.
For wet dry the terms are wet conductor, dry line or dry conductor, off those are your mains and the laterals tie into the mains (laterals are 5/16" tubing. Your description sounds like you have 1 long run, 1000' of 1.5, then 2000' of 1". If that's the case, you need 1000' 1.5", then 1000' 1.25" then 1000' 1" at a minimum. Part will depend on the slope and the number of taps. Ideally you want the wet/dry and your mains at 2%, much steeper causes turbulence. Then you want the laterals (5/16") as steep as you can, up to 15%+, then they may even want to gradually climb the slope rather than go straight up. As for dry conductor size we need more specifics. # taps, layout etc. If my original guesses are correct it should be 2" line, but can't say for sure without all the specifics.

BreezyHill
02-26-2014, 07:27 AM
FoxRun

To answer the question I need more info.
Size of the pump and cfms used on other lines of the system or is this pump on this line only?
Minimum slope of the mains
taps on the mains

The simple answer is yes this will work...the problem is the number of taps that the line will carry.

1.5" at 1000' will carry 15.75 cfms and the 2000' of 1" will carry 6 cfms; but not if they are hooked to a pump that will only produce 10 cfms.

To often the size of the pump is over looked when designing a mains system. This is the key to the entire project.
The level of vac is also relative to the sizing of the system as is the type of releaser and how the releaser is connected to the pump and the distance to the pump.

So get me these answers and I will walk you thru the process. It is very simple when you use the Cornell CFM charts. PM your email and I will send you the charts and calculator sheet so you can look at it as you read the response.

Ben

Fox Run
02-26-2014, 08:49 AM
Maybe a better discription of our setup.
Our system starts at the pump house. Our pump is a DeLeval milk house pump that produces 18cfm (glass jar). We have one main line running straight along side a logging road. It’s starts with 1.5” tubing running from the pump house, up a 2% grade, for 1000ft. Then it reduces down to 1” tubing and shortly starts to climb a 20% grade hill (best guess) for the next 2000ft, were all our taps are. We Tee-off from the 1” mainline with ¾” lines running across the hill about every 40-45 yds. All our blue line runs into the ¾” lines. We have about 2000 taps on this line.
What I wanted to do was put a dry vacuum line in because I didn’t think I was getting any vacuum to the tap and i liked te idea of a whipping system.

JoeJ
02-26-2014, 01:24 PM
I installed a new 2045 tap woods this summer and ran about the same distance (2,850') that you have in your woods. First of all, I have a 56 cfm pump. I plumbed my vacuum, moisture trap and releaser with 3" pipe. From the releaser I ran 2,850' of 1 1/2" wet line and then started the dry line from the releaser with 540" of 3" and continued the remaining 2,310 ' of dry line with 2". The purpose of the first 540' of 3" dry line was to cut the cfm line loss (3 cfm in 540').

The old cfm rule of thumb for the number of taps is 1 cfm per 100 taps. In my opinion, your 18 cfm pump is already too small for 2,000 taps. The problem with the cfm rule of thumb is that the 100
taps per cfm rule does not take into account the law of physics, the friction of air traveling through the pipe and the resulting cfm line loss. The Cornell CFM charts provide very important
information for proper mainline installation.

GeneralStark
02-26-2014, 02:22 PM
You can add a larger 2" + dry line to get vac. out to the woods, but as JoeJ said, your pump is too small. Using the 1cfm to 50 tap rule you should be using a 40 CFM pump (40 CFM @ desired vac. level). Then, probably 3" pipe to 2" pipe for the dry line as JoeJ suggests.

jgrenier
02-26-2014, 07:36 PM
Could some one post a link to the Cornell charts that you speak of it would be greatly appreciated. I looked on there web site and could not find them. Thanks

Thompson's Tree Farm
02-26-2014, 07:54 PM
Call Steve Childs at
Cornell or email him and ask for a hard copy.