Sheaves used in the extraction of oil and gas are of a heavy duty variety and frequently handle loads thru larger diameters and multiple groove configurations.
Two of the more common applications in oil rich areas are Pumpjacks and Mud Pumps.
A Pumpjack like the ones pictured here convert the rotary motion of the motor to a vertical reciprocating motion to drive a pump shaft. It is used to lift liquid out of the well if there is not enough hole pressure for the liquid to flow all the way to the surface.
A Mudpump is a reciprocating piston/plunger device designed to circulate drilling fluid under high pressure down the drill string.
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