The replaceable sludge can is disposed at {HEAD ~ an opening} of {TAIL ~ the bottom} of the external container 
The replaceable sludge can is disposed at { HEAD ~ an opening } of { TAIL ~ the bottom } of the external container
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH