Each carriage is guided by a tongue and slot guiding arrangement, whereby sealing {HEAD ~ pressure} is applied between {TAIL ~ the valve member} and the port plate 
is applied between
Each carriage is guided by a tongue and slot guiding arrangement , whereby sealing { HEAD ~ pressure } is applied between { TAIL ~ the valve member } and the port plate
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH