Sap ladder

[Quabbin Hill Farms]

I need to put in a sap ladder is there a rule of thumb of how many 6 ports stars i need ahead of 200 taps.

Thanks

Greg
Quabbin Hill Maple

[red maples]

use a 2 pipe sap ladder for that many in my opinion they work better especially for that many taps.

[BreezyHill]

I have a little over 250 thru 3x 6 stars and thru a two 6 star ladder further up the system.

If you don't have an issue with the ladder freezing with any sap in them than yes use a straight pipe. I don't use dump ports so my ladders have sap in them when the temp drops below freezing. The bigger the riser diameter the longer it takes to thaw. 1" takes over an hour longer than 5/16 and 3/4" is just under an hour to thaw after the 5/16.

As for a rule of thumb I had been using 15 but found when I added more taps, found that the risers were working better. The number I use now is 20 but it is not set in stone.

It does make a difference as to the height of the risers also. Shorter risers can carry more than longer risers.

[Quabbin Hill Farms]

Thanks how high a lift are your two ladders?

[BreezyHill]

I have seven ladders in a series with 112' of risers. There is a second main that meets at ladder #2 that only lifts 6' roughly. A new main will be hitting the top of ladder #3 adding 250-275 taps and another new main to the bottom of #4 to add another 280+-. Tallest ladder is 18' and shortest is 12-13'.

The length of the main ladder mains is 1800'. 2% slope into the base of each ladder. I use Air Injection(AI) I also have built a few ladder tools to clear a ladder that gets plugged with slush or simply plugged with sap. This has only happened a few times when we had long stretch of sub zero temps last season after a run. Only happened in the all blue risers and mains.

To cure the issue I am extending the dry line to after ladder #5. I have had to redesign my top manifold for the ladders as it failed a test a few weeks back. The old sawing that this is only maple production not rocket science is not as true as it ounce was. I wash my lines and it is important to me to get them clean. We have a 4-H Maple segment of our club. One of them made a great observation as to how my dry line manifold was designed for ease of cleaning yet during season it would not fully drain of sap. I have kept this in the back of my mind since that day and found the manifold would catch about a quart of sap that would pool...back to the drawing board. V4.0 is ready for the saw and glue for next weekend.

I will get you some pics this weekend that most of the beech have dropped their leaves around the ladders.

[Quabbin Hill Farms]

Thanks for the information I only need to bring my line up about 6' to get it run down to the pump.I had about a 10 degree up slope in my 3/4' mainline for about 100' but it taking most of the vacuum draw away to taps past that point of the slope. I am only using a diaphragm pump but I was speaking to Glen Goodrich at the LEME last weekend and he told it would still work.

Thanks

[BreezyHill]

Not sure I am understanding you..you are using a diaphragm pump in place of the ladder or you are using a diaphragm pump to produce the vacuum for the entire system.

[Quabbin Hill Farms]

Yes that is my vacuum source.

[BreezyHill]

Ok...That is going to affect things a little. Diaphragm pumps move fluids very well, air on the other hand is where they are less efficient. Since you are using a relatively short ladder than I believe you will have no problem. We had a rotary roller tube pump that was called a guzzler. It worked fairly well on the ladder when we tried it for a season....but...dad decided it was better for a sap pump in the sugar house to transfer from collection tank to head tank or to the RO tank.

Where you will have an issue is the slush and ice issue with possible damage of the diaphragm. This can be reduced by simply cutting a piece of hardware cloth to screen the intake and inserting the cut to size section into a pvc slip joint and using pipe dope to seal the joint. I use a hair dryer to heat up my flapper valve on my releaser pump when it gets slush in it and doesn't seal well. The hair dryer heating the section of pvc that holds the screen will melt the slush in the am.

[wildlifewarrior]

Hi everyone,
So how high do you think a sap guzzler can lift? We have 100 or so taps and a 7-8 foot lift that we need. Also related to the initial post, we have 6 star ladders, how many should we use to lift about 75 of the taps up that 7-8 feet, one? two?

Thanks everyone!
Mike

[BreezyHill]

The science is still the same in theory. One inch of vacuum will lift sap about 12".

The problem is that a guzzler is not your normal vacuum pump. The normal pump is very efficient in removing air from a chamber. Diaphragm pumps are less efficient in moving air and rather good at moving a non viscous liquid like sap.

If it were possible you set the pump up at your low point and have the pump lift the sap and push the sap to a gravity line to the collection tank.

To get a ladder to work supper well you inject micro bubble that are lifted up the riser and the sap is riding on the air bubble.

While adding air to the system is counter productive in theory; it actually clears the sap from the line so that the chamber( the tubing system) can be evacuated more completely.

To lift 75 taps I would only use a three of the risers on a 6 way. Position them every other on the bottom and cap the three remaining ports and on top you could connect them to three consecutive ports if back feeding becomes an issue but for best balance alternate a riser then a capped port.

Each additional riser that is not needed is simply going to be a point of resistance and a trap for sap to pool; rather than to speed up the risers as fast as possible.

8 feet is a very simple lift and is not going to give the difficulties that arise in multiple lifts.

[mountain man maple]

Why do we stay at 5 taps per branch line but then use 25 taps per lifter on a sap ladder? Wouldn't more 5/16" lines help for higher vacuum at bottom of ladder?

[Thompson's Tree Farm]

When discussing this issue with some experts in tubing installation in Quebec a few years ago, they recommended no more than 25 taps to be lifted by a single six star ladder. I have since followed their advice with great success.

[BreezyHill]

Why do we stay at 5 taps per branch line but then use 25 taps per lifter on a sap ladder? Wouldn't more 5/16" lines help for higher vacuum at bottom of ladder?

Great Question!

First a few terms explained: Vacuum in sap production is a void or chamber that is abscent of matter. Gas, liquid, solids are all matter that are present in the sap lines at one time or another. When the pump is running it will remove as much of the air and tree gases as possible to the ability of the pump.

Rotory vane pump is a pump that is super efficient in removing air due to its use of gravity and centrifical force to compress a set volume of air removed from the tubing system and expel it from the pump. Most pumps can be sped up to increase the amount of air removed from the system to a point of diminishing returns. The higher the vac level the smaller the amount of air removed and the harder this is on a pump to achieve.

Flood oil makes a better seal between the vane and the housing to limit leaks. The oil will also cool the housing and some vane styles, to eliminate heat damage to the pump.

Professional...one who is paid or his/her services. Even a convicted killer is a professional...we pay for their room and board.

Diaphragm pumps have a material that is moved in a single plane to compress a space and over come a check valve system to expel matter to achieve a vacuum. The material or the diaphragm needs to be able to stretch in order to not become damaged during its operation. The check valve needs to be able to operate in a manner that will allow it to open and close rapidly but to produce a very tight seal instantly when forward pressure is removed. Back pressure helps to seal most check valves. For rapid closure the valve needs to have resistance to opening. This limits its ability to remove air but makes it efficient in removing liquids.

Back to the question...The reason is when we are trying to supply vacuum to a tap we are looking to not have a solid column of sap in the line. A line that is not over half full will allow for the gases and a void to form over the sap flow. This void or chamber is where the vacuum is formed. Where sap can be lifted 12" for every inch of mercury, air can be lifted infinitely.
Friction is a killer to flow of matter. Try this simple experiment: Take a equally sized section of mainline and sap tubing. Now place in your hand the section of mainline, inhale as deep as you can and blow thru the tubing. Note how hard and how long it took to exhale one breath. Now do the same on the section of sap tubing. You will notice that it is much harder to blow thru the tubing than the main. To see the affects of friction take a section of mainline that is 10 times longer and blow thru it and have a partner feel the speed or force that the air is leaving the mainline. It will take longer to force the breath thru the pipe and the force at the end of the pipe will be less on the longer section due to friction.
Thus for best vac transfer you want a shorter lateral and only enough to fill the line to, and not past, half. Less fill and length will result in better vac transfer due to less friction
and a larger chamber.

In a ladder we are looking for the opposite end of the spectrum due to gravitational pull. In a ladder gravity is your enemy. While you are trying to lift the sap to the top of the riser gravity is pulling it down the riser. In tubing gravity seperates the sap to the bottom of the tubing and gases travel in the top area of the tubing.

When one watches or studies a sap ladder they will see that a small amount of sap is always lost on the walls of the tubing due to friction this is called slippage. Gravity pulls this sap down the riser. The larger the tubing the larger the amount of slippage. Since air is lifted infinitely, the injection of micro bubble into a tight tubing system, will speed the sap up the riser. The faster the sap rises the more volume of sap that travels thru the ladder.
Now if your having leaks in your tubing system between the ladder and the last tap you may not see any benefit from air injection. Air injection in this case will reduce the vacuum level to a point that the pump is unable to maintain the desired vacuum level, thus reducing the systems capacity.

For a ladder to work supper efficiently and be able to transport sap and supply vacuum there needs to be a balance between air/gases and sap. In my system the ladders that are closer to the sugar house have the highest number of taps per riser as they have the most even flow of sap and bubbles in the system. From ladder #1 to #3 there is no drop in vacuum reading. These ladders are feed at a 2% slope with very little turbulence from saddles and run as many as 34 taps per riser, on a 14' rise.

A 1" main has the same volume as a little more than 10 5/16 risers. By running 12 risers you are compensating for the added friction of the smaller tubing, but potentially slowing the speed of the sap in the riser.

The faster the sap rises the less affect gravity has on the flow. This is especially important when you are coming to freeze time. If you have to many risers your speed is less and the sooner the riser will freeze. Ideally you want the bush to freeze before the mainline, and the mainline to freeze before the riser so that the blue riser will not have as much sap in it as the mainline. My mains from ladders 1 to 3 are black and from 7 to the base of #3 are blue. This helps to thaw them faster to compensate for the cold brook in the evening and to speed thaw time in the am. The further ladders have slightly less canopy cover and a better angle to the east.

I do not recommend that a person start out with as many taps per riser as I have but after one gets a good grasp on adjusting a ladder then you can expand your tap count to find your ladders maximum tap count.

Ladders to require more attention than a sloped tubing system; but the time spent going out to check for leaks daily is a great time to check on the ladder and to fine tune them if needed. The more time you spend watching your ladders the better you become at building and maintaining them. I adjust my injectors at peak flow and then they seldom need adjustment again during the season.

We have run ladders for 40 years and the last three season I have made some of the best changes to their design. I still have redesigns for the top of the ladders o make them even more efficient. Soon we will be installing three new ladders. These would have been better installed in the summer but there is never any spare time on our farm in the summer or fall.

[red maples]

a much simpler answer would be 25 / 6 equals 4.16 taps per tube on a 6 start fitting. but alot of info none the less. or like I said before just run a 2 pipe 1 inch sap ladder its easier and I feel more efficient than the 6 star ladders. I have 2 separate lines one with 95 taps and one with 135 taps the 95 line has star fitting and the 135 has a 2 pipe ladder. by the looks of things the 2 pipe ladder works alot better with a smaller controlled air leak. I am gonna switch the 95 taps to a 2 pipe before the season starts.

in the original post I think there were 200 taps to be lifted. your talking 8- 6 way star lifts going by the 25 tap rule. thats 12 fitting and alot of tubing and work to get the same results from a 2 pipe ladder. make manifolds from PVC run 1" blue put a ball valve in each pipe add a line for an air leak to be controlled by a valve make sure your using lots of gauges so you can monitor before and fter the ladder so you can dial them in to get the highest vacuum with the least amount of air leak and still get effective lift. I paint my PVC pieces black so they melt faster. use heavy duty PVC schedule 40 or better or they will crack sometimes. I have had that happen once before using the cheaper stuff.

[Moser's Maple]

[QUOTE=BreezyHill;261353]

A 1" main has the same volume as a little more than 10 5/16 risers.

actually wouldn't a 1" main want a minimal of 12 and maybe even 18 5/16's to avoid a back up

[BreezyHill]

Jake the very next sentence says 12 for friction adjustments, but you will loose speed of the sap and some times 12 has caused a backup, that 10 did not have. So I just pull off a riser and cap the port and plug the riser, and watch the mainline and the vac gauge.

When pooling occurs you will get a drop in vac readings past the pool. Often pooling is a result of not enough micro bubbles to lift the sap up the riser. I will make a slight adjustment of the injector and clear the pool and walk away and check the ladder after check the lines for leaks. If the pool has reestablished one more adjustment of the injector and a clear the pool. Search for a problem and recheck. Usually if no issue is found then the pool was just from a good flow and the injector needed adjusting. Occasionally I have found a plugged riser and some times on a new ladder the star needs adjusting to even the flow of bubbles.

[Quabbin Hill Farms]

Brad do you have a picture of your 2 pipe ladder i could look at?

[Daveg]

Dear BreezyHill,
Fortunately sap actually is viscous as are all liquids.
Daveg