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FAQnewred.gif (906 bytes)           

Hydraulics Systems Principles of Operation

In following animation, an actuating cylinder controlled by a selector valve.  The selector valve determines to which side of the actuating cylinder the high pressure oil (red colored side) is sent.  The piston rod of the actuating cylinder is connected to the control surface, in this case, an elevator.

As the piston moves out, the elevator moves down. As the piston moves in, the elevator moves up. The selector valve directs the high pressure oil to the appropriate side of the piston head causing movement of the piston in the actuating cylinder. As the piston moves, the oil on the low pressure side (blue colored side) returns to the reservoir since return lines have no pressure!

<img src="images/hydro011.gif" align="bottom" width="496" height="280">
Press on the UP or DOWN arrows to move the stick, UP or DOWN.

      If you don't see the animation, click here to download Macromedia Shockwave Player.

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Updated: March 12, 2004