We have a well which has water but it's a long way down , say 100 meters. At the top of the well I have a see-saw with a bucket at each end , equally balanced.

When the buckets are both empty they balance. When the buckets are both full , they still balance. When one bucket is full it tips the see-saw down and the other end tilts up. When I empty the water it re-balances again. By filling up and emptying the bucket, it causes the see-saw to go up and down. The empty bucket is positioned to drop and scoop up a bucket of water (with every bucket/stroke).

That's probably fine when the water is at the same level but when it's 100 meters down we have to put a pump in the circuit - a sucker rod pump - here is a diagram. Sucker Rod Pump (from Internet Glossary of Pumps)

The sucker rod pump drinks a bit at a time, with valves that help maintain pressure etc. until it sucks the water to the surface - let's say, one bucket at a time. This time I have had to expend let's say, 100 buckets (strokes) of water to raise 1 bucket of water. I call this priming the pump - before we can see any water appear we have to prime the pump to build up the pressure (like a lift pump http://www.animatedsoftware.com/pumpglos/liftpump.htm).

My query is: if the above is correct and it takes 100 buckets (or you could say 100 strokes) to lift 1 bucket of water - how many strokes does it take to life the next bucket of water ?

One stroke or 100.

I think it is one stroke but my friend thinks it's still 100.

Can anyone enlighten me.

Thanks
John

It sounds like it's just 1 pump, once you fill the pump with water, it will continue to be full of water all the way to the top, due to the valves, and so only 1 pump will be needed to pull a bucket of water from the bottom, and thus push a bucket of water out the top.

If you leave it for some time, maybe the valves will leak a little, and you'll have to do a few pumps to get water coming out again, but over a short period it shouldn't leak that much.

If you imagine each bucket of water is represented by a ball. And put balls in the bottom of a pipe that can hold 100 balls. Once you put in the 101st ball, the first ball will pop out the top, then you put in the 102nd ball, and the 2nd ball will pop out the top.

Good luck! :)

It sounds like it's just 1 pump -

Having "sounds" in bold may appear we are not yet exactly clear - how can we become clearer - although it would appear that it is 1 pump (yipee!)

I would be pleased to hear any doubts or circumstance that might contradict or confirm such.

Thank you

I mean, it seems intuitive that it's 1 pump, and I'm wondering why your friend thinks it is 100.

He said, "The principle of ordinary levers such as your lever pump is that the mass x gravity x the distance from the fulchrum is equal on both sides of the fulchrum, (friction being idealised as zero). Thus a short distance x a mass can lift a smaller mass by a longer distance and vica versa. In your pump, you have to get as much water out as you put in so ultimately the masses are the same. Thus you have a problem because the delivery lift required is larger than the driving height. Note that a ram pump can deliver an effective head on one side far greater than the fall of water driving the pump BUT only if you use far more water driving the pump than you actually deliver. A ram pump only works if you can get rid of the excess water on the driving side for LITTLE OR NO EXTRA ENERGY COST. In your case I don't know how you can achieve this without extra pumping. Put another way, if you could use a fall of x meters to generate a lift of 20 x X meters then the world would have had no energy problems since before the Greeks or the Universe would have been so different as to make our life unimaginable. That is not to say that there may not be something that emerges to astonish us all but in my view, this is not the case here."

He must have the wrong idea in his head - often the case when people think they are talking about the same thing but are not - nevertheless , if you can understand what he is saying then, it may shed some light.

I don't really understand how the lever thing is important.. With the first pump you are lifting one bucket of water, the second pump you are lifting 2 buckets, etc until you are lifting 100 buckets of water by 1 meter.

You are doing more and more work until the water reaches the top, there is no energy deficit here. You will continue to lift 100 buckets of water each time you pump after this, and you will get 1 bucket out the top.

So I take it that he is thinking something else - and you and I are agreed - after the water reaches the surface then it sounds very much like once you put in the 101st ball, the first ball will pop out the top, then you put in the 102nd ball, and the 2nd ball will pop out the top.

I'll be back, later.
Cheers

This is not the energy deficit you are looking for :)

Perhaps lifting 1 bucket of water in a sucker rod pump at -100 meters we must allow hydrostatic pressure since a column of water is forming - which would/might demand a 100 bucket stroke i.e.. 100 times the energy to pop the next ball in at the bottom.

Otherwise OR
The upper chamber in the srp is isolated (and yes there is a valve there) which makes the upper chamber quite removed from the inlet (at the bottom) which means it's isolated from the water column!! So we can slip a ball in without a struggle

When I look at the srp, it suggests 1 full stroke would equal 1 full suck, and that was capable to 10,000 feet would appear to be (there's that word again) not affected by height - so is that the illusion - it looks like 1 stroke but it's actually calculable to be far more depending on how high the water column is.

Sucker Rod Pump (from Internet Glossary of Pumps)

And then I look at the srp and say, nay, it is connected with a rope, the horses head travels the same distance, the rope travels the same distance, the stroke distance is the same - it would stop if there was too much drag or pressure, but they just keep pumping all day (guess I'm talking about the typical srp's I saw in California)(none in Australia) - so the power (probably diesel) that runs them varies accordingly... hmm.

When is a water column not a water column

When is a water column exempt from pressure at the base preventing the next gulp

Does it take 1 elephant to push the 100th ball or 100 elephants - if the column of water is isolated somehow we get a free lunch

I'm off the sleep

Good luck

A detailed description of a sucker rod pump
2.972 How a Sucker Rod Pump (Oil Well Pump) Works

A calculator for sucker rod pumps
Sucker Rod Pump Calculator

Here is some info from Mr Rod Sucker himself with a costing of around $10/day to bring up 100 barrels per day - which doesn't sound expensive... but actually sounds absurd.
Electrical & Horsepower

Pardon my avid interest, but it's a make or break deal to know what is happening.

This pdf just might have enough info for a physics expert to decipher if the Sucker Rod Pump uses some valid tricks to overcome the enormous hydrostatic pressure to take the next 'gulp' - at the bottom which in turn pushes out the same - at the top... or it just uses a mighty big motor with a lot of push. The fate of the free world depends on it.

http://www.osti.gov/bridge/servlets/...wable/3261.pdf

Hullo hullo, and I quote from this article:

Patriot Down Stroke Sucker Rod Pump

"The PATRIOT PUMP loads the barrel on the upstroke with the bottom discharge valve closed held on seat by the hydrostatic pressure in the tubing. Since the plunger is solid and longer than the barrel, there is NO hydrostatic load on the plunger. On the upstroke, all the pumping unit and prime mover are lifting is the buoyant weight of the rod string."

sounds like it to me but hey, the free world will owe a huge debt of gratitude if a certain physics expert can confirm.

The thing is, I don't know how you would make a pump that would only lift 1 bucket at a time, unless it actually was a bucket on a string.

The only remaining question is how much man power do you need.

Well, Village pumps lift water from wells to the surface, and those are man powered, so I doubt it takes the marvel of modern technology to do the same nowadays.

I don't know the details, but I don't see why it isn't doable, it's up to you to find the right thing for the job though, I don't have time to read through this stuff att he moment :)

1 bucket = 1 portion (the amount is not important) the concept is. A portion is a pre-determined amount calculated in the design - so 1 bucket might be 1000 litres of water - and in essence it is on the end of a string but it's called a "rod".

Yes how much power indeed. Well I've seen references indicating 15 HP motors with a costing of $10/day... so that doesn't sound big - but it also sounds too easy.

Yes - hand-pumps are not rocket science.

Guess you're having fun (the fun is in having lots to do and not doing it.) Thanks for your help. Much appreciated.

My findings:

The Sucker Rod Pump uses a counter-weight and 10-15 hp motor to drive a rod with a piston at the base some 10,000 feet to pump up oil by creating around 4000 psi and thereby having the pressure to build a water column from the bottom up - so one gulp at a time enables it to build a water column so the first gulp appears at the top many gulps later - it's OK for the oil industry 'cause they don't care if it's inefficient 'cause we pay for it.

It's not a ram, it works like I hoped, but it only drinks around 10 liters per gulp so I need around 1000 suckers which doesn't sound like that many since one is born everyday.

10 litres x 6 drinks/minute x 60 minutes x 24 hours = 86,400 liters per day or 865 units

There's nothing like coal to get the job done.

Cheers