When the crosshead flexes, the position of the transverse seal relative to the inner circumference of {HEAD ~ the cylinder} and hence the abutment of the transverse seal at {TAIL ~ the inner circumference} are not changed 
When the crosshead flexes , the position of the transverse seal relative to the inner circumference of { HEAD ~ the cylinder } and hence the abutment of the transverse seal at { TAIL ~ the inner circumference } are not changed
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH