End of the trough is connected to {HEAD ~ exhaustor means} which suck {TAIL ~ the fibre fleece} towards injector  
End of the trough is connected to { HEAD ~ exhaustor means } which suck { TAIL ~ the fibre fleece } towards injector
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH