The inner periphery of each intermediate ring is formed with an axis eccentric with {TAIL ~ respect} to {HEAD ~ the axis} of the casing 
The inner periphery of each intermediate ring is formed with an axis eccentric with { TAIL ~ respect } to { HEAD ~ the axis } of the casing
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH