... Collar, Shaft Ring and Seat RingThrust Collar, Series AS, LS, GS, WS, ZS, TRA, TRB, TRC TRD.Series AS thrust collar ... rigidity, Series AS collar shall play its full action.Series GS, WS, LS thrust collars are made of bearing steel with ... the quenching process. The outer surface of GS seat ring and the inner surface of WS shaft ring ...