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SeanD
04-23-2020, 10:39 AM
I'm thinking of upgrading the mainline I use to offload sap from the IBC on my truck to my collection tank at the SH. Right now, I have a 60ish-foot 1" black water pipe on a mainline wire that drains the tank by gravity dropping maybe 5 feet as it goes downhill from valve to top of tank.

I wish I had timed how long it takes to drain a typical load of sap. I'm not always in a hurry. There's plenty of stuff to do while it drains. Sometimes, though I do want to unload faster to go collect again. I may add a second tank to the truck down the road.

I'm thinking of bumping it up to 1.5" blue mainline. Any idea on the flow rates of 1" vs. 1.5"? Is 2" insanely fast? I do take the line down every year, so ease of unrolling and rolling is a factor.

littleTapper
04-23-2020, 11:35 AM
Just using cross-section area (which probably isn't the whole picture). 1" line is .79 sq-in, 1.5" is 1.77 sq-in. So, 2.24x the area. At same pressure it should flow that amount more. 2" would be 3.97x the area.

DrTimPerkins
04-23-2020, 11:41 AM
Just using cross-section area (which probably isn't the whole picture). 1" line is .79 sq-in, 1.5" is 1.77 sq-in. So, 2.24x the area. At same pressure it should flow that amount more. 2" would be 3.97x the area.

That is correct, assuming you don't have some restriction (fitting, valve, etc) somewhere in the line that necks it down to a common size, in which case you won't see any real difference due to pipe size.

Bucket Head
04-23-2020, 07:24 PM
I can not speak on gravity from experience but I can speak on the difference when pumping through 1" and 2" hose. For years, I both collected and then unloaded with the same, 1" inlet/outlet gas engine pump. It took well over twenty minutes to pump off the 450 gal. tank. Last year I bought a 2" pump for unloading. (Still like the smaller pump for going barrel to barrel while collecting. Easier to move around.) I can now unload the tank in minutes! I've never timed it but it's not more than five. Just an incredible difference. Gravity will be a little slower but you should see a noticeable decrease in unloading time with bigger hose.

Steve

steam maker
04-23-2020, 07:25 PM
Maybe a little redneck but what about 6/7 ten ft pieces of pvc pipe and appropriate amount of fernco couplings . Start in the sugarhouse and run it to dump site , bag tie it to the wire like mainline. Rather undo a fernco than try and roll up 1 1/2 mainline .

maple flats
04-23-2020, 07:54 PM
I also never timed it, but I used to unload 2 and sometimes 3 full IBC totes by gravity using 1.5" PVC hose. It likely took about 5 minutes x 2 or 3 depending on if I was emptying 2 or 3 IBCs and the drop in elevation was only about 2'. Just remember to open the cap on the IBC or you will collapse the tote.
On mine when I did that all 3 were mounted on a gooseneck trailer and they were plumbed together so they had a common discharge. I just removed the caps, tested the sap sugar, recorded the amount of sap, then I opened the valves on each, all emptied equally as they progressed. My 1.5" hose was 30' to the closest tank and 45' if I had to go to the second tank or the third.

bill m
04-24-2020, 07:15 AM
Steam Maker has a great suggestion. Rolling up 1 1/2 inch tubing sucks and being only 60 ft. it could be harder. You can get pvc in 20 ft. lengths and the per foot cost should be a little cheaper.

maple flats
04-24-2020, 05:00 PM
At one lease I pumped to empty the 1000 gal tan, which was about 5' below the elevation of the IBC tanks on the gooseneck on the road. For that one, I used 1.5" PVC pipe, connected together using Fernco type connectors. It was 40' from the tank to the IBC's I used 30' of the PVC pipe, as described and 2 lengths of flexible PVC pipe, 1 from the described PVC to the WX15 pump, and another from the pump to the tanks plumbed together on the trailer. Each IBC had it's own valve, I'd fill one at a time, as it got full I opened the next valve and closed the full tank's valve. However I don't recall what the actual pump run time was, but I filled 2 IBC's arrival to departure, set-up and clean up included in just about 25-30 minutes.

SeanD
04-24-2020, 05:53 PM
Wow. That's all awesome experience to share. I hadn't considered rigid pipe. I would have thought it was too much hassle with the Fernco's to boot. I'll think about that. I do like those numbers for 1.5" pipe/hose. If I'm honest with myself, there will be a second tank on my truck in a year or two.

maple flats
04-24-2020, 08:04 PM
Those fernco coupled pipe stayed there year to year. Once assembled they didn't get unhooked. I had cam lock caps or plugs on each end to keep dirt and critters out.

GeneralStark
04-24-2020, 09:29 PM
Are fern-co connectors food grade? :)