The system also serves as {HEAD ~ a testing system} for {TAIL ~ control umbilicals} that usually are located near the pipelines 
for
The system also serves as { HEAD ~ a testing system } for { TAIL ~ control umbilicals } that usually are located near the pipelines
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH