On 4/13/2011 10:47 AM, LSMFT wrote:
....

Well how do those oil well pumps pump up the oil? It's just a hand pump
with a big motor and cam wheel.

No, it isn't...

The rocking beam or pumpjack pumps are sucker rods that lift the oil.
Very much like the sucker rods of an old windmill except larger scale.

Didn't find a quick illustration of workings of oil pumpjack; principle
is same as shown in this link for water.

http://www.simplepump.com/OUR-PUMPS/Pump-System.html

Newer wells may use hydraulic lift or even have jet pumps installed.

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