# Ram Pump question

Discussion in 'Homesteading Questions' started by caberjim, Nov 4, 2005.

1. ### caberjimStableboy III

Messages:
426
Joined:
Feb 19, 2004
Location:
Maryland
I want move water from a fairly fast flowing but not very deep creek that is about 300-400 feet away. I think the ram pump would be ideal, but there is no drop area as the land is very flat there. Would the pressure from the flowing water be enough to drive the pump or is the drop absolutely necessary? I am under the impression that the pump is drive by water pressure and the drop is necessary to build up pressure from a spring, pond or slow moving stream.

My thought is a wide pipe, maybe 6 inches that sits on the highest and fastest flowing section, reducing down to 4, then 2 then 1, right into the pump. Then push the water over the water troughs in the pastures and a split to a holding tank for other uses. Troughs will probably drain to the pond.

thoughts? Ideas?

Messages:
126
Joined:
Apr 18, 2005
Location:
Hawaii

3. ### agmantooagmantooSupporter

Messages:
10,855
Joined:
May 22, 2003
Location:
Zone 7
Drop is necessary

4. ### caberjimStableboy III

Messages:
426
Joined:
Feb 19, 2004
Location:
Maryland
Okay, but why? if it a pressure issue, why would the reducing pipes and strong flow not provide that?

5. ### SolarGaryWell-Known Member

Messages:
1,495
Joined:
Sep 7, 2005
Location:
Montana
Hi,

On the link below, take a look at the section (near the bottom of page) on sling pumps -- they seem to be a good match for your situation:

http://www.lifewater.ca/ram_pump.htm

-------
I think that you would need a very very fast stream to make your scheme work.
If (say) your stream is flowing at 5mph (7.3 ft/sec), then you can use this velocity energy to raise the level of the water (basically trade velocity head for water height). In this case, if you turned all the velocity head into height, you would get:

Velocity head = 0.5 (density of water)(velocity^2)

= (0.5) )((1.92 lb-sec^2/ft)/ft^3) (7.3 ft/sec)^2 = 52 lb/ft^2 or 0.36 psi -- this would translate into raising the water level by 0.8 ft -- not too much.

You can measure this on your stream with some clear tubing. Put one end of the tube in the stream pointing directly into the flow. Bend the other end so that it goes straight up. The water will rise in the vertical portion of the tube -- how high it rises tells how much "fall" you could generate for a ram pump by using converting the velocity of the water into height to drive the ram pump.
I don't think that having the tube start at a large diameter and go down to a smaller diameter will make any difference in how high the water rises.

Gary
www.BuildItSolar.com

Messages:
10,855
Joined:
May 22, 2003
Location:
Zone 7
7. ### jeffreyc256Well-Known Member

Messages:
106
Joined:
Sep 24, 2005
Location:
Alabama
I have a ram pump i have never had the time to tinker with. I have a similiar problem to you excellent flow but little fall. My situation will require running the pipe up stream a good bit to get the required fall. I sure would like to see it work

8. ### ace admirerWell-Known MemberSupporter

Messages:
1,875
Joined:
Oct 4, 2005
its not really just pressure or just flow that makes the ram work...its flow down a long pipe at a volicity(sp) that will "water hammer" when the valve slams shut.. you will probably need a hundred or so feet of steel pipe to make it work best...how much drop could you get in 100-200 ft. you need the long pipe to "pack" the water near the ram, the inerta from the flow down the long pipe generates the high pressure at the ram. others have the moonshot math...but basically for each foot of fall, you will be able to push a percentage of water 20 feet up. neat neat devices.

Messages:
11,301
Joined:
Feb 10, 2004
Location:
So Cal Mtns
10. ### caberjimStableboy III

Messages:
426
Joined:
Feb 19, 2004
Location:
Maryland

Well, I went down to the creek with some pipe and a level and played in the water for a while. I don't see any way I can get even a 2-3 foot drop for a ram pump, so that is out. I think water wheel is the only choice. I don't suppose anyone here else has tried making one? Oh well, this should be a lot of fun and a good learning tool for the kids.

11. ### ace admirerWell-Known MemberSupporter

Messages:
1,875
Joined:
Oct 4, 2005
yeah, i've made a few of each and a couple of bankie turbines to boot....but....you're gonna need fall for a waterwheel also....

can't you fill a few of the polyelethane seed bags with sand and make a dam to back up a fall? or is your land reallllllly flat?

12. ### ExplorerWell-Known MemberSupporter

Messages:
2,644
Joined:
Dec 1, 2003
Location:
Far West in the White Mountains, Arizona
The water wheel shown will depend upon the velocity of the flow. A slow moving stream will do much.

13. ### ace admirerWell-Known MemberSupporter

Messages:
1,875
Joined:
Oct 4, 2005
Hi, didn't see a photo of your water wheel....but...is it an undershot type per chance.. all three types of water wheels are gravity devices not volicity (dang my spelling!) but the undershot will make use of the least amount of fall...(the buckets actually work as a dam. backing up the inflow of water to form a fall (even if small as compaired to the other two.) the efficiency of the undershot is fairly low...well its low as heck. i guess we need to get some raw data like flows and falls and amount of work desired to be done...man! i love the thought of using water to do work...