The bladder expends while applying a pressure on {HEAD ~ the thermoplastic sheet} against the wall from {TAIL ~ the bottom portion} to the top portion 
The bladder expends while applying a pressure on { HEAD ~ the thermoplastic sheet } against the wall from { TAIL ~ the bottom portion } to the top portion
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH