The operation pipe is actuated and drives {TAIL ~ the piston and piston valve} in {HEAD ~ the perpendicular direction} 
The operation pipe is actuated and drives { TAIL ~ the piston and piston valve } in { HEAD ~ the perpendicular direction }
OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD