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Step 10Howsitdodat?
So here goes for the operation of the pump.
As the pump cycle begins, water flows down the stand pipe, and up through the swing check valve. Water begins to flow faster and faster around the flapper in the check valve, until friction draws the flapper up, slamming it closed. This causes a pressure spike in the pump body, as the water flowing down the stand pipe at some speed no longer has anywhere to go. This pressure is relieved by some of the water flowing across the spring check valve, over onto the pressure chamber side of the pump. Once past the swing check valve, it cannot return, and has to stay there. When the pressure difference across the spring check valve drops, the valve will close and water will stop flowing through it. The lower pressure will allow the swing check valve to open again, beginning the cycle all over again.
Troubleshooting
So what if this doesn't happen? Well, first things first, check and make sure that it's "on". That is to say, make sure both the 1-1/4" and 3/4" valves are in fact open.
Sometimes water will flow out of the swing check valve, then the valve will slam closed, but nothing will happen. If this occurs, tap on the flapper in the check valve to open it up again, and let the cycle begin again. In theory these pumps need some back pressure (coming from the pressure tank side) to operate, but I've never had any trouble getting mine going with just some basic tapping and fiddling.
Tuning
Now that it's working, can you make it work better? You'll find that there's a maximum height that the pump can deliver water to. Be patient when trying to find this, as it takes a little while for the pump to achieve the pressure required to raise the water up higher and higher. There are formulas that will tell you how high you can theoretically pump water based on the source water head. Feel free to look them up.
Tuning ram pumps mostly involves varying the water velocity that results in the swing check valve closing. A higher water velocity will generate a larger pressure spike, allowing you to pump to greater heights. But it will also cause a slower cycle, so you pump more slowly. If the valve closes at a lower water velocity, it will take less time for the water to reach that velocity, so the pump will cycle faster, and the water pumped faster, but you will not be able to pump as high. So that's the trade off. Keep in mind though, that this will work without interference 24 hours a day, so combining it with a holding tank, you can get a decent supply of water built up.
To tune this specific design, you take advantage of how gravity acts on the flapper. When the check valve is pointing straight up in the air, the full force of gravity holds the flapper down, so the water must flow past the flapper faster to generate enough drag to raise the full weight of the flapper. By rotating the pump about the main line, you put the flapper's degree of freedom at an angle to the force of gravity, so that less drag is required to move the flapper. You could work out all of this fairly easily with a bit of trig, but I feel it would serve you little use out in the field. Just play around with it, you should find a position that works well for your application.
No Power?
Well, no. This pump derives its power from the potential energy of the water uphill, and by wasting (not in a bad sense) the majority of the water that flows through the stand pipe. It only pumps a small fraction of the water that actually travels down that pipe. But that's fine if you have a stream already flowing down a hillside. Before, you weren't doing anything with all that potential / kinetic energy. Now you are. Hooray for you!
As the pump cycle begins, water flows down the stand pipe, and up through the swing check valve. Water begins to flow faster and faster around the flapper in the check valve, until friction draws the flapper up, slamming it closed. This causes a pressure spike in the pump body, as the water flowing down the stand pipe at some speed no longer has anywhere to go. This pressure is relieved by some of the water flowing across the spring check valve, over onto the pressure chamber side of the pump. Once past the swing check valve, it cannot return, and has to stay there. When the pressure difference across the spring check valve drops, the valve will close and water will stop flowing through it. The lower pressure will allow the swing check valve to open again, beginning the cycle all over again.
Troubleshooting
So what if this doesn't happen? Well, first things first, check and make sure that it's "on". That is to say, make sure both the 1-1/4" and 3/4" valves are in fact open.
Sometimes water will flow out of the swing check valve, then the valve will slam closed, but nothing will happen. If this occurs, tap on the flapper in the check valve to open it up again, and let the cycle begin again. In theory these pumps need some back pressure (coming from the pressure tank side) to operate, but I've never had any trouble getting mine going with just some basic tapping and fiddling.
Tuning
Now that it's working, can you make it work better? You'll find that there's a maximum height that the pump can deliver water to. Be patient when trying to find this, as it takes a little while for the pump to achieve the pressure required to raise the water up higher and higher. There are formulas that will tell you how high you can theoretically pump water based on the source water head. Feel free to look them up.
Tuning ram pumps mostly involves varying the water velocity that results in the swing check valve closing. A higher water velocity will generate a larger pressure spike, allowing you to pump to greater heights. But it will also cause a slower cycle, so you pump more slowly. If the valve closes at a lower water velocity, it will take less time for the water to reach that velocity, so the pump will cycle faster, and the water pumped faster, but you will not be able to pump as high. So that's the trade off. Keep in mind though, that this will work without interference 24 hours a day, so combining it with a holding tank, you can get a decent supply of water built up.
To tune this specific design, you take advantage of how gravity acts on the flapper. When the check valve is pointing straight up in the air, the full force of gravity holds the flapper down, so the water must flow past the flapper faster to generate enough drag to raise the full weight of the flapper. By rotating the pump about the main line, you put the flapper's degree of freedom at an angle to the force of gravity, so that less drag is required to move the flapper. You could work out all of this fairly easily with a bit of trig, but I feel it would serve you little use out in the field. Just play around with it, you should find a position that works well for your application.
No Power?
Well, no. This pump derives its power from the potential energy of the water uphill, and by wasting (not in a bad sense) the majority of the water that flows through the stand pipe. It only pumps a small fraction of the water that actually travels down that pipe. But that's fine if you have a stream already flowing down a hillside. Before, you weren't doing anything with all that potential / kinetic energy. Now you are. Hooray for you!
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Sep 30, 2009. 6:53 AMmarean
says:
Very nice way to display your instructions. I already have a Clemson ram that does not work and I am going to take it apart and attempt to build this one. If I can get it up and running I will do cart wheels. Thanks Marean
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1
May 28, 2009. 9:16 AMmathieulj
says:
Excellent application for a phenomenon that has been known for a while. Good work and keep it up.
Reply
May 9, 2009. 11:23 AMcosmo1kitty
says:
Pure Genius!!! Unlike some of your other commentators...I actually constructed this yesterday and put it to the test. I have a very small creek that runs year round and wanted to utilize it for my landscaping needs. My husband constructed the pump and we went to the creek for set up. We dug a small area out as a catch and placed a large waste basket in it to catch as much water as possible. We fastened a small metal mesh across the top of the waste basket to keep out as much debris as possible. My husband then connected a 3" pipe to the basket for 30 feet and then reduced down to a 2" for 20 feet and finally down to 1 1/4" for 20 feet. The complete fall from basket to hydrolic ram pump is approximately a 12 foot elevation drop. Needless to say, the water shot out the end of the pump like a fire hydrant. Why did we do this, you might ask???? Well, simple....our creek is about 150' BELOW our home and needed to pump up this elevation in a 3/4" poly pipe for a 500 feet distance. It took a bit to get the pump going. In fact, we thought it wasn't going to work. Nothing was happening. However, I read the very short sentence that stated that you may have to push the check valve flapper down a few times to get the pressure up to par. I pushed it down probably 15 times before the pump started doing on its own. I was amazed!!!! We ran up the hil and within five minutes we had water!!! I figured maybe a trickle...being the elevation difference, but we had a nice steady flow. We figure that it will only take about two days to fill up a 1500 gallon holding tank. Thanks for the awesome invention!!!!!!!
Reply
1
May 10, 2009. 4:39 AMhabolooby (author)
says:
Haha, that is excellent! Great to hear of a successful build and implementation, and I'm really glad that it worked out so well. Cheers!
Reply
May 10, 2009. 10:22 PMcosmo1kitty
says:
It's awesome!!! We checked it today to see if it was still working....and it was!!! We can't wait to water our garden with FREE, NO ELECTRICITY REQUIRED, water!!! Pure Genius! As Yes....this is ACESSENDING up an elevation rise of approximately 150' !!! It's easy to dig canals and ditches for lateral flow....it takes a brain to figure out how to get water to flow AGAINST gravity. Thanks again.
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