Individually compliant segments for split ring hydrodynamic face seal

Abstract

Embodiments of the present disclosure are directed toward a face seal including a stator ring configured to be disposed about a rotor of a turbine, wherein the stator ring includes a first ring segment and a second ring segment which are circumferentially split and configured to cooperatively form the stator ring, and bearing elements disposed between the first and second ring segments and configured to enable relative axial motion between the first and second ring segments at interfaces between the first and second ring segments. The stator ring further includes hydrodynamic surface features on surfaces of the first and second ring segments configured for facing the rotor, wherein the hydrodynamic surface features comprise Y-shaped grooves each comprising a stem portion extending from a middle region of stator ring and splitting into inner and outer branches extending towards inner and outer diameters of the stator ring and terminating prior to the inner and outer diameters.

1 . A system, comprising:
 a steam turbine; and   a face seal of the steam turbine, comprising:
 a rotor ring coupled to a rotor of the steam turbine; and 
 a stator ring coupled to a stationary housing of the steam turbine, wherein the stator ring is circumferentially split into a plurality of circumferential segments with one or more bearing elements disposed between each of the plurality of circumferential segments, wherein the one or more bearing elements are configured to enable relative axial movement of the plurality of segments relative to one another, 
 hydrodynamic surface features on a sealing surface of at least one of the rotor ring and the stator ring facing the other of the rotor ring and the stator ring, 
 wherein the hydrodynamic surface features comprise Y-shaped grooves each comprising a stem portion extending from a middle region of the rotor ring or the stator ring and splitting into inner and outer branches extending towards inner and outer diameters of the rotor ring or the stator ring respectively. 
   
     
     
         2 . The system of  claim 1  wherein the inner and outer branches of the Y-shaped grooves terminate prior to the respective inner and outer diameters. 
     
     
         3 . The system of  claim 2  further comprising a plurality of holes for feeding a gas into the stem portions of respective ones of the Y-shaped grooves. 
     
     
         4 . The system of  claim 1  wherein the rotor ring comprises the Y-shaped grooves. 
     
     
         5 . The system of  claim 1  wherein the stator ring comprises the Y-shaped grooves. 
     
     
         6 . The system of  claim 5  wherein the Y-shaped grooves are situated on the circumferential segments. 
     
     
         7 . The system of  claim 5  further comprising a plurality of pads configured to extend from the circumferential segments, wherein the Y-shaped grooves are situated on the plurality of pads. 
     
     
         8 . A turbine, comprising:
 a rotor;   a stationary housing disposed about the rotor; and   a face seal disposed about the rotor, comprising:
 a rotor ring coupled to or integral with the rotor; and 
 a stator ring coupled to the stationary housing, wherein the stator ring comprises:
 a first segment; 
 a second segment; and 
 at least two bearing elements, wherein the first and second segments are circumferentially split, and the at least two bearing elements are disposed between the first and second segments, and wherein the first segment, the second segment, and the at least two bearing elements cooperatively form the stator ring, 
 
 hydrodynamic surface features on a sealing surface of at least one of the rotor ring and the stator ring facing the other of the rotor ring and the stator ring, 
 wherein the hydrodynamic surface features comprise Y-shaped grooves each comprising a stem portion extending from a middle region of the rotor ring or the stator ring and splitting into inner and outer branches extending towards inner and outer diameters of the rotor ring or the stator ring respectively. 
   
     
     
         9 . The turbine of  claim 8  wherein the inner and outer branches of the Y-shaped grooves terminate prior to the respective inner and outer diameters. 
     
     
         10 . The turbine of  claim 9  further comprising a plurality of holes for feeding a gas into the stem portions of respective ones of the Y-shaped grooves. 
     
     
         11 . The turbine of  claim 8  wherein the rotor ring comprises the Y-shaped grooves. 
     
     
         12 . The turbine of  claim 8  wherein the stator ring comprises the Y-shaped grooves. 
     
     
         13 . The system of  claim 12  wherein the Y-shaped grooves are situated on the first and second segments. 
     
     
         14 . The system of  claim 12  further comprising a plurality of pads configured to extend from the first and second segments, wherein the Y-shaped grooves are situated on the plurality of pads. 
     
     
         15 . A system, comprising
 a stator ring configured to be disposed about a rotor of a turbine, wherein the stator ring comprises
 a first ring segment and a second ring segment which are circumferentially split and configured to cooperatively form the stator ring, 
 at least one bearing element disposed between the first and second ring segments and configured to enable relative axial motion between the first and second ring segments at interfaces between the first and second ring segments, 
 hydrodynamic surface features on surfaces of the first and second ring segments configured for facing the rotor, wherein the hydrodynamic surface features comprise Y-shaped grooves each comprising a stem portion extending from a middle region of stator ring and splitting into inner and outer branches extending towards inner and outer diameters of the stator ring and terminating prior to the inner and outer diameters. 
   
     
     
         16 . The system of  claim 15  further comprising a plurality of holes for feeding a gas into the stem portions of respective ones of the Y-shaped grooves.