Thereby, the internal ring can deform over {HEAD ~ a range} of {TAIL ~ shocks} but is prevented from deforming by the casing or metal ring above this shock range 
Thereby , the internal ring can deform over { HEAD ~ a range } of { TAIL ~ shocks } but is prevented from deforming by the casing or metal ring above this shock range
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH