Rotary piling - GIF

Rotary piling.

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Previously:

Foundation piling rotary drilling rig - GIF
How subsea pilings are made - GIF
Installing secant piling walls - GIF and photo
Removing barnacles from pilings - GIF
Technical animation of subsea piling installation - video

I know that is a powerful pile driver, but that is sliding in very easily.

Why is it called a rotary piling? Nothing is rotating.

Neil