Abstract: In an elastic fluid turbine employing a segmented packing ring mounted in a ring-like stationary holder or diaphragm having upper and lower half-parts which meet at a horizontal joint and circumscribe a rotor to minimize leakage between the components, interfitting butt ends on certain of the packing ring segments at the diaphragm horizontal joint, and cam pins on the diaphragm at the horizontal joint and engageable with slots in said certain of the packing ring segments for accurately positioning the packing ring segments relative to the horizontal joint.

Abstract: In a steam turbine having retractable, spring-loaded, segmented, arcuate packaging rings and holders suspended in the turbine casing and circumscribing the turbine rotor, the packing rings and holders being interengaged by a hook fit and the packing rings being movable by steam pressure between opened and closed position relative to the holders and the rotor, the improvement which comprises providing each of the packing rings and holders with identical mating, curved profiles for providing full contact between the packing rings and holders in the opened position of the packing rings.