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Robert McGowen
10-09-2011, 4:52 PM
If you're trying to fill a 2000 gal hole and the pump rate is 500gal/min and the pump stroke is 10in and pump liner is 6in, how many pump strokes will it take to fill the hole? Any idea?

I am guessing you determine the volume of a cylinder 10" tall with a diameter of 6", then determine how much water in gallons fill that volume, then divide that number into 2000. I am stuck on determining how much water will fill the cylinder, if in fact this is the correct way to find the answer.Thanks!

Perry Holbrook
10-09-2011, 5:55 PM
There are 231 cubic inches in a gallon.

Perry

Tom Winship
10-09-2011, 6:19 PM
Robert,
Additionally to Perry's input, the volume of the cylinder is pi*r*r*l=3.14*3*3*10=282.6 cubic inches. The volume of the hole in cubic inches is 231*2000=462,000. So dividing the 462,000 cu.in. hole volume by the 282.6 cu. in./stroke equals 1634.8 strokes.
Can't figure what the pump rate has to do with the problem unless there is a seperate question on how long to fill the hole......... 4 minutes.
Remember this is Aggie math I'm using and may not be acceptable to those of the orange persuasion.

Robert McGowen
10-09-2011, 7:24 PM
Yeah, once I found out what Perry said, 231 cubic inches for a gallon, everything else was pretty simple. I was just overlooking the obvious, as it was an unknown factor. I also think that the 4 minutes to fill the hole was a red herring or a part of the answer for another problem. Thanks!

P.S. I know being an old Aggie, Tom, that you probably did this in your head! The kids are getting a minor in math and I think that they were way over-thinking the problem......