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Is it always necessary to have a long pipe (100ft) to lift water using hydraulic ram pump?

If the stream used as the water source has ample water volume and swift flow, can we use a shorter source pipe with a large diameter, say 6 inches x 10 foot long, reduced down to 2 inches leading into the pump to provide the drive water. Why is it necessary to have a long (100 ft. pipe) in Hydraulic Ram Pump?

4 Answers


Binaya. I am no ram pump expert, so others may provide a better answer. I am only going to provide you with this link which provides detailed guidance on getting your design right. Once you have looked at this and checked your specific situation against these design principles, and if you still have specific questions, then please ask these again as part of this same question thread. The link is here Ram Pump Design


Hi Binaya, I remember a practical at University when we set a similar system up ( If not the same) . As you, I didn't understand a need for 100ft pipe when a much shorter one was much more practical on many levels. As a result of the economies, mine was the only one not to work, the reason, the pipe was too short. The optimum pipe length had been set at 100ft, possibly by trial and error over the years, but no one else at the time could explain why that was, theoretically. I will do a little more research and try and find out, possibly the links above or books listed may do if you can get hold of them. I hope this helps. Best wishes Pauline R RedR


I think it has something to do with the settling of turbulence in the water flow.

ErikH gravatar imageErikH ( 2013-12-12 11:08:54 )

Thank you Erikh and Pauline.


Hi ErikH and Binaya, Yes I think it does. We were studying open channel flows, eddies, waves and the water hammer effect around the same time, however we couldn't prove with calculations why 100ft was the optimum length for this type of pump. The following term we had other areas to tackle I suppose and it was put to the back of our minds. Pauline