{HEAD ~ The internal diameter} of the tube section 20 is equal to {TAIL ~ the internal diameter} of the adjacent parts of pipes 10 and 12 
is equal to
{ HEAD ~ The internal diameter } of the tube section 20 is equal to { TAIL ~ the internal diameter } of the adjacent parts of pipes 10 and 12
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH