In addition, the link forms {HEAD ~ a loop} with {TAIL ~ both ends} thereof being connected to the surface installation  
In addition , the link forms { HEAD ~ a loop } with { TAIL ~ both ends } thereof being connected to the surface installation
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH