The first tube sheet is mounted in the primary inner shell while {HEAD ~ the second tube sheet} is connected to {TAIL ~ the secondary inner shell} 
is connected to
The first tube sheet is mounted in the primary inner shell while { HEAD ~ the second tube sheet } is connected to { TAIL ~ the secondary inner shell }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL