Patent Publication Number: US-10316861-B2

Title: Two-piece multi-surface wear liner

Description:
BACKGROUND 
     The operating environment for gas turbine engines is extremely harsh. Vibrations due to normal use at operating speeds are extreme. Additionally, the operating temperature experienced by some engine components is extremely high. The feet of vanes are among the many components that experience wear in the engine due to vibrations and high temperature. Wear liners are used between the vane feet and an engine case to reduce wear. However, current wear liner designs utilize a single piece design. Vane foot are installed circumferentially into the case one vane at a time, which makes it difficult to install the vanes with the wear liner. 
     The fit of the vane foot within the case typically includes a clearance fit accommodating relative thermal growth of the components during operation. The relative movement can cause wear as well as provide an undesired leak path across the wear liner. 
     SUMMARY 
     A liner assembly for placement between a mounting foot of a platform and a case of a gas turbine engine includes first and second annular liner segments configured to move independently of each other. The first annular liner segment is configured to be mounted on at least a portion of a radially outward surface of the mounting foot. The first annular liner segment includes a first flat portion and a first curved portion extending from a first end of the first annular liner segment. The second annular liner segment is configured to be mounted on at least a portion of a radially inward surface of the mounting foot. The second annular liner segment includes a second flat portion and a second curved portion extending from a first end of the second annular liner segment. 
     A gas turbine engine includes a case, a stator, and a liner assembly. The case includes a J-groove disposed in the case. The stator is mounted within the case and includes a vane, a platform, and a mounting foot. The platform is attached to a radially outward end of the vane. The mounting foot is mounted within the J-groove and includes a radially outward surface, a radially inward surface, and a first end. The liner assembly includes first and second annular liner segments configured to move independently of each other. The first annular liner segment is mounted on at least a portion of the radially outward surface of the mounting foot. The second annular liner segment is mounted on at least a portion of the radially inward surface of the mounting foot. 
     A method of assembling a vane and a liner assembly in a gas turbine engine includes inserting first and second annular liner segments of the liner assembly into a J-groove in a case of the gas turbine engine so as to mount the first and second annular liner segments into the case. A mounting foot of the vane is inserted between the first and second annular liner segments so as to mount the foot of the vane into the J-groove of the case. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a cross-section view of a gas turbine engine. 
         FIG. 2  is a cross-section view of a compressor case of the gas turbine engine with a stator stage. 
         FIG. 3A  is a cross-section view of the stator, the compressor case, and a first liner assembly. 
         FIG. 3B  is a cross-section view of the stator, the compressor case, and a second liner assembly. 
         FIG. 3C  is a cross-section view of the stator, the compressor case, and a third liner assembly. 
         FIG. 4  is a cross-section view of the first liner assembly. 
     
    
    
     DETAILED DESCRIPTION 
     The present application discloses a wear liner assembly including a two-piece configuration. The two-piece wear liner protects both the ID and OD surfaces of a case J-groove. The two-piece design also eliminates stacking of tolerances among the liners and the foot, thereby allowing the stator to have a tighter fit into the case. The split between the two-pieces of the wear liner allow both pieces to move independently, which makes circumferential stator installation into the case J-groove easier. 
       FIG. 1  is a cross-section view of gas turbine engine  10  including a liner/vane assembly of the present invention. The view in  FIG. 1  is a longitudinal sectional view along engine centerline C L .  FIG. 1  shows gas turbine engine  10  including fan blade  12 , compressor  14 , combustor  16 , turbine  18 , high-pressure rotor  20 , low-pressure rotor  22 , and engine case  24 . Compressor  14  includes low-pressure rotor stages  26 L, high-pressure rotor stages  26 H, low-pressure stator stages  27 L, and high-pressure stator stages  27 H. Turbine  18  includes high-pressure rotor stages  28 H, low-pressure rotor stages  28 L, high-pressure stator stages  29 H, and low-pressure stator stages  29 L. 
     As illustrated in  FIG. 1 , fan blade  12  extends from engine centerline C L  near a forward end of gas turbine engine  10 . Compressor  14  is disposed aft of fan blade  12  along engine centerline C L , followed by combustor  16 . Turbine  18  is located adjacent combustor  16 , opposite compressor  14 . High-pressure rotor  20  and low-pressure rotor  22  are mounted for rotation about engine centerline C L . High-pressure rotor  20  connects a high-pressure section of turbine  18  to a high-pressure section of compressor  14 . Low-pressure rotor  22  connects a low-pressure section of turbine  18  to fan blade  12  and a low-pressure section of compressor  14 . Rotor stages  26  and stator stages  28  are arranged throughout compressor  14  and turbine  18  in alternating rows. High-pressure rotor stages  26 H and  28 H connect to high-pressure rotor  20  and low-pressure rotor stages  26 L and  28 L connect to low-pressure rotor  22 . Engine case  24  surrounds turbine engine  10  providing structural support for compressor  14 , combustor  16 , and turbine  18 , as well as containment for air flow through engine  10 . 
     In operation, air flow F enters compressor  14  after passing between fan blades  12 . Air flow F is compressed by the rotation of compressor  14  driven by high-pressure turbine  18 . The compressed air from compressor  14  is divided, with a portion going to combustor  16 , a portion bypasses through fan  12 , and a portion employed for cooling components, buffering, and other purposes. Compressed air and fuel are mixed and ignited in combustor  16  to produce high-temperature, high-pressure combustion gases F P . Combustion gases F P  exit combustor  16  into turbine section  18 . 
     Stator stages  27 L,  27 H,  29 H, and  29 L properly align the flow of air flow F and combustion gases F P  for an efficient attack angle on subsequent rotor stages  26 L,  26 H,  28 H, and  28 L respectively. The flow of combustion gases F P  past low pressure rotor stages  28 L of turbine section  18  drives rotation of low-pressure rotor  22  (which drives fan blades  12  to produce thrust F S  from gas turbine engine  10 ) and low-pressure compressor stages  26 L. High pressure rotor stages  28 H of turbine section drive high-pressure rotor  20 , which drives high-pressure rotor stages  26 H of compressor  14 . 
     Although embodiments of the present invention are illustrated for a turbofan gas turbine engine for aviation use, it is understood that the present invention applies to other aviation gas turbine engines and to industrial gas turbine engines as well. 
       FIG. 2  shows stator stage  28 , compressor case  30  with forward J-groove  32 F and aft J-groove  32 A, vane  34 , platform  36  with forward foot  38  and aft foot  40 , forward liner assembly  42 F with first annular liner segment  44 F and second annular liner segment  46 F, and aft liner assembly  42 A with first annular liner segment  44 A and second annular liner segment  46 A. Although detailed discussion of aft foot  40  and aft liner assembly  42 A is included herein, it should be understood that a configuration of aft liner assembly  42 A is applicable to a wide variety of locations throughout gas turbine engine  10  such as with forward liner assembly  42 F with forward foot  38 , as well as other locations such as low or high pressure sections of compressor section  14  or turbine section  18 . 
     Compressor case  30  is a portion of engine case  24  that surrounds compressor  14 . Stator stage  28  is a circumferential array of a plurality of vanes  34 . Vane  34  is a cantilevered vane which extends radially inward from platform  36  toward centerline axis C L . In other non-limiting embodiments, vanes  34  may be supported from both inner and outer radial ends (with respect to centerline axis C L ) and vanes  34  may be disposed in other sections of gas turbine engine  10  such as turbine  18  ( FIG. 1 ). Platform  36  is a radially outer platform of stator stage  28 . Forward foot  38  is an engagement feature located on an upstream end of platform  36  (upstream direction shown as right to left in  FIGS. 1-4 ). Aft foot  40  is an engagement feature located on a downstream end of platform  36  (downstream direction shown as left to right in  FIGS. 1-4 ). Aft foot  40  and forward foot  38  are disposed on opposing ends of platform  36 . 
     Liner assembly  42 A is a two-piece wear liner and includes first annular liner segment  44 A and second annular liner segment  46 A. First annular liner segment  44 A and second annular liner segment  46 A are single wear liner pieces. In one non-limiting embodiment, first annular liner segment  44 A and second annular liner segment  46 A are full-hoop, but can also extend less than full-hoop. 
     As will be discussed subsequently, platform  36  is adapted with forward foot  38  and aft foot  40  that are disposed within compressor case  30  to allow vanes  34  to be supported therefrom. First and second annular liner segments  44 A and  46 A are disposed between compressor case  30  and platform  36 . First and second annular liner segments  44 A and  46 A dampen vibration between vane  34  and compressor case  30 , accommodate thermal growth between platform  36  and compressor case  30 , and allow for ease of assembly and disassembly of vane  34 . 
       FIG. 3A  shows a cross-section view of stator stage  28  including vane  34  and platform  36 , compressor case  30  with J-groove  32 A (including first surface  52  and second surface  54 ), aft foot  40  (including first end  56 , radially outward surface  58 , radially inward surface  60 , undercut  62 , outer chamfer  64 , and inner chamfer  66 ), liner assembly  42 A with first annular liner segment  44 A (including first end  68 , second end  69 , first flat portion  70 , and first curved portion  72 ) and second annular liner segment  46 A (including first end  74 , second end  75 , second flat portion  76 , second curved portion  78 , and second hook portion  80 ), and split  82 . 
     Compressor case  30  is a portion of engine case  24  extending circumferentially about compressor  14  of gas turbine engine  10 . J-groove  32 A is a slot or groove extending circumferentially within compressor case  30 . Stator stage  28  is a stator vane of gas turbine engine  10  that includes vane  34  and platform  36 . Vane  34  is a blade or airfoil. Platform  36  is an end of stator stage  28  configured for attachment to a case such as compressor case  30 . 
     Liner assembly  42 A is a two-piece wear liner including first annular liner segment  44 A and second annular liner segment  46 A. First annular liner segment  44 A and second annular liner segment  46 A may comprise any material including characteristics which are desired and/or critical for the specific implementation of liner assembly  42 A such as metal, ceramic, mineral, plastic, or any other suitable abrasion resistant material. First end  68  and second end  69  are ends of first annular liner segment  44 A. First flat portion  70  is a portion of first annular liner segment  44 A that maintains a constant diameter along a length of first flat portion  70 . First curved portion  72  is a curved portion of first annular liner segment  44 A that increases in diameter along an axially upstream direction (right to left in  FIGS. 3A-3C ). First end  74  and second end  75  are ends of second annular liner segment  46 A. Second flat portion  76  is a portion of second annular liner segment  46 A that maintains a constant diameter along a length of second flat portion  76 . Second curved portion  78  is a curved portion of second annular liner segment  46 A that decreases in diameter along an axially upstream direction (right to left in  FIGS. 3A-3C ). Second hook portion  80  is a curved portion of second annular liner segment  46 A that forms a hook shape. 
     Split  82  is a space extending between second end  69  of first annular liner segment  44 A and second end  75  of second annular liner segment  46 A. In one non-limiting embodiment, split  82  can include a distance greater than or equal to zero inches. In another non-limiting embodiment, split  82  can be configured such that second end  69  of first annular liner segment  44 A and second end  75  of second annular liner segment  46 A can overlap each other. 
     Aft foot  40  is a hook or mounting feature located along a first end of platform  36 . First end  56  is a downstream end of aft foot  40  (with a downstream direction from left to right in  FIGS. 3A-3C ). Radially outward surface  58  is a surface located along a radially outer edge of aft foot  40 . Radially inner surface  60  is a surface located along a radially inner edge of aft foot  40 . Undercut  62  is a cutout taken from first end  56  of aft foot  40 . Outer chamfer  64  is an angled cut taken from first end  56  of aft foot  40 . Inner chamfer  66  is another angle cut taken from first end  56  of aft foot  40 . 
     Compressor case  30  is a portion of engine case  24  that extends axially along compressor  14  of gas turbine engine  10 . J-groove  32 A extends into compressor case  30  to create an annular slot for receiving liner assembly  42 A and aft foot  40 . Stator stage  28  is attached to compressor case  30  via aft foot  40  engaging with J-groove  32 A of compressor case  30 . Vane  34  can be attached to or formed as a single piece with platform  36 . Platform  36  is attached to compressor case through engagement of aft foot  40  with J-groove  32 A of compressor case  30 . 
     Liner assembly  42 A is disposed between aft foot  40  and compressor case  30 . Liner assembly  42 A with first annular liner segment  44 A and second annular liner segment  46 A extends in a circumferential direction about centerline axis C L  of gas turbine engine  10  ( FIG. 1 ). First annular liner segment  44 A is configured to be mounted on at least a portion of radially outward surface  58  of the aft foot  40 . Second annular liner segment  46 A is configured to be mounted on at least a portion of radially inward surface  60  of the aft foot  40 . First annular liner segment  44 A and second annular liner segment  46 A are configured to receive aft foot  40  of platform  36 . First annular liner segment  44 A and second annular liner segment  46 A are also configured to move independently of each other. A portion of first annular liner segment  44 A is disposed between radially outward surface  58  of aft foot  40  and compressor case  30 . A portion of second annular liner segment  46 A is disposed between radially inward surface  60  of aft foot  40  and compressor case  30 . First curved portion  72  is disposed upstream of first flat portion  70  relative to an orientation of stator stage  28  in gas turbine engine  10 . Second curved portion  78  is disposed upstream of second flat portion  76 . Second hook portion  80  extends or hooks around first end  56  of aft foot  40 . 
     Split  82  extends between second end  69  of first annular liner segment  44 A and second end  75  of second annular liner segment  46 A. In  FIG. 3A , split  82  is disposed along outer chamfer  64  of aft foot  40 . Second hook portion  80  extends around first end  56  of aft foot  40  such that second end  74  of second annular liner segment  46 A is disposed radially outward from first end  56  of aft foot  40 . Aft foot  40  is disposed in J-groove  32 A of compressor case  30  in between first annular liner segment  44 A and second annular liner segment  46 A. 
     Undercut  62  is disposed along radially outward surface  58  of aft foot  40  at first end  56 . Outer chamfer  64  is disposed at an intersection of radially outward surface  58  of aft foot  40  and first end  56 . Inner chamfer  66  is disposed at an intersection of radially inward surface  60  of aft foot  40  and first end  56 . 
     During assembly of compressor case  30 , first and second annular liner segments  44 A and  46 A of liner assembly  42 A are inserted into J-groove  32 A so as to mount first and second annular liner segments  44 A and  46 A into compressor case  30 . First annular liner segment  44 A and second annular liner segment  46 A fit into J-groove  32 A such that first annular liner segment  44 A and second annular liner segment  46 A maintain a tight fit with compressor case  30 . After first annular liner segment  44 A and second annular liner segment  46 A are inserted into J-groove  32 A of compressor case  30 , aft foot  40  of stator stage  28  is circumferentially inserted and installed into J-groove  32 A. For example, aft foot  40  of platform  36  is inserted into J-groove  32 A of compressor case  30  along a circumferential direction of compressor case  30 . 
     As aft foot  40  is installed between first annular liner segment  44 A and second annular liner segment  46 A in J-groove  32 A, first annular liner segment  44 A and second annular liner segment  46 A are able to move independently from each other allowing relative radial motion between first annular liner segment  44 A and second annular liner segment  46 A. As aft foot  40  is inserted into J-groove  32 A, first annular liner segment  44 A is pressed against radially outward surface  58  of aft foot  40  and against first surface  52  of J-groove  32 A and second annular liner segment  46 A is pressed against radially inward surface  60  of aft foot  40  and against second surface  54  of J-groove  32 A. 
     Liner assembly  42 A with first annular liner segment  44 A and second annular liner segment  46 A forms a wear liner to protect aft foot  40  and surfaces of J-groove  32 A within compressor case  30  from abrasion and wear caused during installation and operation of gas turbine engine  10 . Split  82  enables first annular liner segment  44 A and second annular liner segment  46 A to move independently from each other. The location of split  82  in  FIG. 3A  is shown as disposed along a radially outward portion of J-groove  32 A. In this non-limiting embodiment, a radially inward side of aft foot  40  is loaded more than a radially outward side of aft foot  40 . In other non-limiting embodiments (see  FIGS. 3B and 3C ), split  82  can be disposed at other radial and axial locations along aft foot  40  depending on where and how aft foot  40  is loaded. 
     The relative radial motion between first annular liner segment  44 A and second annular liner segment  46 A allows for smaller tolerances and a tighter fit between aft foot  40 , first annular liner segment  44 A, second annular liner segment  46 A, and compressor case  30  than a single-piece liner configuration would have. Liner assembly  42 A allows each of first annular liner segment  44 A and second annular liner segment  46 A to account for their own tolerances instead of having to account for the stacking of tolerances with a single-piece liner configuration. This allows for more freedom of motion between first annular liner segment  44 A and second annular liner segment  46 A during assembly which allows for easier circumferential assembly of stator stages  28  in compressor case  30 . 
       FIG. 3B  shows a cross-section view of compressor case  30  including J-groove  32 A, stator stage  28  including vane  34  and platform  36 , aft foot  40  (including first end  56 , radially outward surface  58 , radially inward surface  60 , undercut  62 , outer chamfer  64 , and inner chamfer  66 ), liner assembly  42 A′ including first annular liner segment  44 A′ (including first end  68 ′, second end  69 ′, first flat portion  70 ′, first curved portion  72 ′, and first hook portion  84 ′) and second annular liner segment  46 A′ (including first end  74 ′, second end  75 ′, second flat portion  76 ′, second curved portion  78 ′, and second hook portion  80 ′), and split  82 ′. 
     Liner assembly  42 A′ is a two-piece wear liner including first annular liner segment  44 A′ and second annular liner segment  46 A′. First annular liner segment  44 A′ and second annular liner segment  46 A′ may comprise any material including characteristics which are desired and/or critical for the specific implementation of liner assembly  42 A′ such as metal, ceramic, mineral, plastic, or any other suitable abrasion resistant material. First end  68 ′ and second end  69 ′ are ends of first annular liner segment first  40 ′. First flat portion  70 ′ is a portion of first annular liner segment  44 A′ that maintains a constant diameter along a length of first flat portion  70 ′. First curved portion  72 ′ is a curved portion of first annular liner segment  44 A′ that increases in diameter along an axially upstream direction (right to left in  FIGS. 3A-3C ). First hook portion  84 ′ is a curved portion of first annular liner segment  44 A that forms a hook shape. First end  74 ′ and second end  75 ′ are ends of second annular liner segment  46 A′. Second flat portion  76 ′ is a portion of second annular liner segment  46 A′ that maintains a constant diameter along a length of second flat portion  76 ′. Second curved portion  78 ′ is a curved portion of second annular liner segment  46 A′ that decreases in diameter along an axially upstream direction (right to left in  FIGS. 3A-3C ). Second hook portion  80 ′ is a curved portion of second annular liner segment  46 A′ that forms a hook shape. 
     Split  82 ′ is a space extending between second end  69 ′ of first annular liner segment  44 A′ and second end  75 ′ of second annular liner segment  46 A′. In one non-limiting embodiment, split  82 ′ can include a distance greater than or equal to zero inches. In another non-limiting embodiment, split  82 ′ can be configured such that second end  69 ′ of first annular liner segment  44 A′ and second end  75 ′ of second annular liner segment  46 A′ can overlap each other. 
     Liner assembly  42 A′ is disposed between aft foot  40  and compressor case  30 . Liner assembly  42 A′ with first annular liner segment  44 A′ and second annular liner segment  46 A′ extends in a circumferential direction about centerline axis C L  of gas turbine engine  10  ( FIG. 1 ). First annular liner segment  44 A′ is configured to be mounted on at least a portion of radially outward surface  58  of the aft foot  40 . Second annular liner segment  46 A′ is configured to be mounted on at least a portion of radially inward surface  60  of the aft foot  40 . First annular liner segment  44 A′ and second annular liner segment  46 A′ are configured to receive aft foot  40  of vane  34 . First annular liner segment  44 A′ and second annular liner segment  46 A′ are also configured to move independently of each other. A portion of first annular liner segment  44 A′ is disposed between radially outward surface  58  of aft foot  40  and compressor case  30 . A portion of second annular liner segment  46 A′ is disposed between radially inward surface  60  of aft foot  40  and compressor case  30 . First curved portion  72 ′ is disposed upstream of first flat portion  70 ′ relative to an orientation of stator stage  28  in gas turbine engine  10 . First hook portion  84 ′ extends or hooks around a radially outward portion of first end  56  of aft foot  40 . Second curved portion  78 ′ is disposed upstream of second flat portion  76 ′. Second hook portion  80 ′ extends or hooks around a radially inward portion of first end  56  of aft foot  40 . 
     Split  82 ′ extends between second end  69 ′ of first annular liner segment  44 A′ and second end  75 ′ of second annular liner segment  46 A′. In  FIG. 3B , split  82 ′ is disposed radially in-between outward surface  58  and radially inward surface  60  of aft foot  40 . Second hook portion  80 ′ extends around first end  56  of aft foot  40  such that second end  75 ′ of second annular liner segment  46 A′ is disposed radially in-between between outward surface  58  and radially inward surface  60  of aft foot  40 . First hook portion  84 ′ extends around first end  56  of aft foot  40  such that second end  69 ′ of first annular liner segment  44 A is disposed radially in-between between outward surface  58  and radially inward surface  60  of aft foot  40 . Aft foot  40  is disposed in J-groove  32 A of compressor case  30  in between first annular liner segment  44 A′ and second annular liner segment  46 A′. 
     Undercut  62  is disposed along radially outward surface  58  of aft foot  40  at first end  56 . Outer chamfer  64  is disposed at an intersection of radially outward surface  58  of aft foot  40  and first end  56 . Inner chamfer  66  is disposed at an intersection of radially inward surface  60  of aft foot  40  and first end  56 . 
     During assembly of compressor case  30 , liner assembly  42 A′ is inserted into J-groove  32 A. First annular liner segment  44 A′ and second annular liner segment  46 A′ fit into J-groove  32 A such that first annular liner segment  44 A′ and second annular liner segment  46 A′ maintain a tight fit with compressor case  30 . After first annular liner segment  44 A′ and second annular liner segment  46 A′ are inserted into J-groove  32 A of compressor case  30 , aft foot  40  of stator stage  28  is circumferentially inserted and installed into J-groove  32 A. For example, aft foot  40  of platform  36  is inserted into J-groove  32 A of compressor case  30  along a circumferential direction of compressor case  30 . As aft foot  40  is installed between first annular liner segment  44 A′ and second annular liner segment  46 A′ in J-groove  32 A, first annular liner segment  44 A′ and second annular liner segment  46 A′ are able to move independently from each other allowing relative radial motion between first annular liner segment  44 A′ and second annular liner segment  46 A′. 
     Liner assembly  42 A′ with first annular liner segment  44 A′ and second annular liner segment  46 A′ forms a wear liner to protect aft foot  40  and surfaces of J-groove  32 A within compressor case  30  from abrasion and wear caused during installation and operation of gas turbine engine  10 . Split  82 ′ enables first annular liner segment  44 A′ and second annular liner segment  46 A′ to move independently from each other. 
     The location of split  82 ′ in  FIG. 3B  is shown as disposed along a radial mid-point of J-groove  32 A. In this non-limiting embodiment, the radially inward side of aft foot  40  is loaded about the same as the radially outward side of aft foot  40 . In other non-limiting embodiments (see  FIGS. 3A and 3C ), split  82 ′ can be disposed at other radial and axial locations along aft foot  40  depending on where and how aft foot  40  is loaded. 
       FIG. 3C  shows a cross-section view of compressor case  30  including J-groove  32 A, stator stage  28  including vane  34  and platform  36 , aft foot  40  (including first end  56 , radially outward surface  58 , radially inward surface  60 , undercut  62 , outer chamfer  64 , and inner chamfer  66 ), liner assembly  42 A″ including first annular liner segment  44 A″ (including first end  68 ″, second end  69 ″, first flat portion  70 ″, first curved portion  72 ″, and first hook portion  84 ″) and second annular liner segment  46 A″ (including first end  74 ″, second end  75 ″, second flat portion  76 ″, second curved portion  78 ″, and second hook portion  80 ″), and split  82 ″. 
     Liner assembly  42 A″ is a two-piece wear liner including first annular liner segment  44 A″ and second annular liner segment  46 A″. First annular liner segment  44 A″ and second annular liner segment  46 A″ may comprise any material including characteristics which are desired and/or critical for the specific implementation of liner assembly  42 A″ such as metal, ceramic, mineral, plastic, or any other suitable abrasion resistant material. First end  68 ″ and second end  69 ″ are ends of first annular liner segment first  40 ″. First flat portion  70 ″ is a portion of first annular liner segment  44 A″ that maintains a constant diameter along a length of first flat portion  70 ″. First curved portion  72 ″ is a curved portion of first annular liner segment  44 A″ that increases in diameter along an axially upstream direction (right to left in  FIGS. 3A-3C ). First hook portion  84 ″ is a curved portion of first annular liner segment  44 A that forms a hook shape. First end  74 ″ and second end  75 ″ are an ends of second annular liner segment  46 A″. Second flat portion  76 ″ is a portion of second annular liner segment  46 A″ that maintains a constant diameter along a length of second flat portion  76 ″. Second curved portion  78 ″ is a curved portion of second annular liner segment  46 A″ that decreases in diameter along an axially upstream direction (right to left in  FIGS. 3A-3C ). 
     Split  82 ″ is a space extending between second end  69 ″ of first annular liner segment  44 A″ and second end  75 ″ of second annular liner segment  46 A″. In one non-limiting embodiment, split  82 ″ can include a distance greater than or equal to zero inches. In another non-limiting embodiment, split  82 ″ can be configured such that second end  69 ″ of first annular liner segment  44 A″ and second end  75 ″ of second annular liner segment  46 A″ can overlap each other. 
     Liner assembly  42 A″ is disposed between aft foot  40  and compressor case  30 . Liner assembly  42 A″ with first annular liner segment  44 A″ and second annular liner segment  46 A″ extends in a circumferential direction about centerline axis C L  of gas turbine engine  10  ( FIG. 1 ). First annular liner segment  44 A″ is configured to be mounted on at least a portion of radially outward surface  58  of the aft foot  40 . Second annular liner segment  46 A″ is configured to be mounted on at least a portion of radially inward surface  60  of the aft foot  40 . First annular liner segment  44 A″ and second annular liner segment  46 A″ are configured to receive aft foot  40  of vane  34 . First annular liner segment  44 A″ and second annular liner segment  46 A″ are also configured to move independently of each other. A portion of first annular liner segment  44 A″ is disposed between radially outward surface  58  of aft foot  40  and compressor case  30 . A portion of second annular liner segment  46 A″ is disposed between radially inward surface  60  of aft foot  40  and compressor case  30 . First curved portion  72 ″ is disposed upstream of first flat portion  70 ″ relative to an orientation of stator stage  28  in gas turbine engine  10 . First hook portion  84 ″ extends or hooks around first end  56  of aft foot  40 . Second curved portion  78 ″ is disposed upstream of second flat portion  76 ″. 
     Split  82 ″ extends between second end  69 ″ of first annular liner segment  44 A″ and second end  75 ″ of second annular liner segment  46 A″. In  FIG. 3C , split  82  is disposed along inner chamfer  66  of aft foot  40 . First hook portion  84 ″ extends around first end  56  of aft foot  40  such that second end  69 ″ of first annular liner segment  44 A″ is disposed radially inward from first end  56 . Aft foot  40  is disposed in J-groove  32 A of compressor case  30  in between first annular liner segment  44 A″ and second annular liner segment  46 A″. 
     Undercut  62  is disposed along radially outward surface  58  of aft foot  40  at first end  56 . Outer chamfer  64  is disposed at an intersection of radially outward surface  58  of aft foot  40  and first end  56 . Inner chamfer  66  is disposed at an intersection of radially inward surface  60  of aft foot  40  and first end  56 . 
     During assembly of compressor case  30 , liner assembly  42 A″ is inserted into J-groove  32 A. First annular liner segment  44 A″ and second annular liner segment  46 A″ fit into J-groove  32 A such that first annular liner segment  44 A″ and second annular liner segment  46 A″ maintain a tight fit with compressor case  30 . After first annular liner segment  44 A″ and second annular liner segment  46 A″ are inserted into J-groove  32 A of compressor case  30 , aft foot  40  of stator stage  28  is circumferentially inserted and installed into J-groove  32 A. For example, aft foot  40  of platform  36  is inserted into J-groove  32 A of compressor case  30  along a circumferential direction of compressor case  30 . As aft foot  40  is installed between first annular liner segment  44 A″ and second annular liner segment  46 A″ in J-groove  32 A, first annular liner segment  44 A″ and second annular liner segment  46 A″ are able to move independently from each other allowing relative radial motion between first annular liner segment  44 A″ and second annular liner segment  46 A″. 
     Liner assembly  42 A″ with first annular liner segment  44 A″ and second annular liner segment  46 A″ forms a wear liner to protect aft foot  40  and surfaces of J-groove  32 A within compressor case  30  from abrasion and wear caused during installation and operation of gas turbine engine  10 . Split  82 ″ enables first annular liner segment  44 A″ and second annular liner segment  46 A″ to move independently from each other. 
     The location of split  82 ″ in  FIG. 3C  is shown as disposed along a radially inward portion of J-groove  32 A. In this non-limiting embodiment, a radially outward side of aft foot  40  is loaded more than a radially inward side of aft foot  40 . In other non-limiting embodiments (see  FIGS. 3A and 3C ), split  82 ″ can be disposed at other radial and axial locations along aft foot  40  depending on where and how aft foot  40  is loaded. 
       FIG. 4  shows a cross-section view of liner assembly  42 A with first annular liner segment  44 A, second annular liner segment  46 A, and channel  86  extending between first annular liner segment  44 A and second annular liner segment  46 A. First annular liner segment  44 A includes first thickness T 1 , first length L 1 , and first axial span S 1 . Second annular liner segment  46 A includes second thickness T 2 , second length L 2 , and second axial span S 2 . Second hook portion  78  of second annular liner segment  46 A includes first corner  88  with first radius of curvature R 1  and second corner  90  with second radius of curvature R 2 . 
     Channel  86  is a space or gap along a radial direction between first annular liner segment  44 A and second annular liner segment  46 A. In one non-limiting embodiment, a distance of channel  86  is approximately twelve times larger than second thickness T 2  of second annular liner segment  46 A, such as is shown in  FIG. 4 . In general, the distance of channel  86  is greater than zero and is configured to match or be slightly greater than a radial width of aft foot  40 . 
     First and second thickness T 1  and T 2  can range from 0.001 to 0.025 inches (0.048 to 0.762 millimeters). In one non-limiting embodiment, first and second thickness T 1  and T 2  are equal. In another non-limiting embodiment, first and second thickness T 1  and T 2  are not equal. In other non-limiting embodiments, first and second thicknesses T 1  and T 2  can vary based upon a localized need for wear resistance along aft foot  40 . 
     First length L 1  is a length of first annular liner segment  44 A taken from end to end. Second length L 2  is a length of second annular liner segment  46 A taken from end to end. In  FIGS. 3A and 4 , first length L 1  is smaller than second length L 2  of second annular liner segment  46 A. In other non-limiting embodiments, first length L 1  can be equal to or greater than second length L 2  (see  FIGS. 3B and 3C ). 
     First axial span S 1  of first annular liner segment  44 A is a distance along an axial direction that first annular liner segment  44 A spans. Second axial span S 2  of second annular liner segment  46 A is a distance along an axial direction that second annular liner segment  46 A spans. In  FIGS. 3A and 4 , first axial span S 1  is greater than second axial span S 2 . In other non-limiting embodiments, first axial span S 1  can be equal to or less than second axial span S 2 . 
     First radius of curvature R 1  is a radius of curvature of first corner  88  of second annular liner segment  46 A. Second radius of curvature R 2  is a radius of curvature of second corner  90  of second annular liner segment  46 A. First radius of curvature R 1  and second radius of curvature R 2  are shown as being approximately five times greater than second thickness T 2  of second annular liner segment  46 A and less than half of the distance of channel  86 . In other non-limiting embodiments, first radius of curvature R 1  and/or second radius of curvature R 2  can be different thicknesses than each other, greater or less than five times greater than second thickness T 2  of second annular liner segment  46 A, and greater than or equal to half of the distance of channel  86 . In another non-limiting embodiment, first radius of curvature R 1  and second radius of curvature R 2  are approximately equal. In other non-limiting embodiments, first radius of curvature R 1  can be less than or greater than second radius of curvature R 2 . First radius of curvature R 1  and second radius of curvature R 2  are configured to match the curvatures of corresponding corners of J-groove  32 A in compressor case  30 . 
     The above description of second annular liner segment also extends to the corresponding elements of first annular liner segment  46 A as shown in  FIGS. 3B and 3C  (such as first hook portion  84 ). 
     Discussion of Possible Embodiments 
     The following are non-exclusive descriptions of possible embodiments of the present invention. 
     A liner assembly for placement between a mounting foot of a platform and a case of a gas turbine engine includes first and second annular liner segments configured to move independently of each other. The first annular liner segment is configured to be mounted on at least a portion of a radially outward surface of the mounting foot. The first annular liner segment includes a first flat portion and a first curved portion extending from a first end of the first annular liner segment. The second annular liner segment is configured to be mounted on at least a portion of a radially inward surface of the mounting foot. The second annular liner segment includes a second flat portion and a second curved portion extending from a first end of the second annular liner segment. 
     The assembly of the preceding paragraph can optionally include, additionally and/or alternatively, any one or more of the following features, configurations and/or additional components. 
     The first and second annular liner segments can be configured to receive the mounting foot of the platform. 
     A split can be disposed between a second end of the first annular liner segment and a second end of the second annular liner segment. 
     The split can be disposed along the radially outward surface of the mounting foot, and further wherein the second annular liner segment can comprise a second hook portion extending around a first end of the mounting foot such that the second end of the second annular liner segment can be disposed radially outward from the first end of the mounting foot. 
     The split can be disposed along the radially inward surface of the mounting foot, and further wherein the first annular liner segment can comprise a first hook portion extending around a first end of the mounting foot such that the second end of the first annular liner segment can be disposed radially inward from the first end of the mounting foot. 
     The first annular liner segment can comprise a first hook portion extending around the first end of the mounting foot and the second annular liner segment can comprise a second hook portion extending around the first end of the mounting foot such that the split between the second end of the first annular liner segment and the second end of the second annular liner segment can be disposed radially in-between the radially outward and radially inward surfaces of the mounting foot. 
     A gas turbine engine includes a case, a stator, and a liner assembly. The case includes a J-groove disposed in the case. The stator is mounted within the case and includes a vane, a platform, and a mounting foot. The platform is attached to a radially outward end of the vane. The mounting foot is mounted within the J-groove and includes a radially outward surface, a radially inward surface, and a first end. The liner assembly includes first and second annular liner segments configured to move independently of each other. The first annular liner segment is mounted on at least a portion of the radially outward surface of the mounting foot. The second annular liner segment is mounted on at least a portion of the radially inward surface of the mounting foot. 
     The assembly of the preceding paragraph can optionally include, additionally and/or alternatively, any one or more of the following features, configurations and/or additional components. 
     The case can comprise a compressor case of the gas turbine engine. 
     The first and second annular liner segments can be configured to receive the mounting foot of the stator. 
     A split can be disposed between the first and second annular liner segments. 
     The split can be disposed along the radially outward surface of the mounting foot. 
     The split can be disposed along the radially inward surface of the mounting foot. 
     The split can be disposed along the first end of the mounting foot. 
     A method of assembling a vane and a liner assembly in a gas turbine engine includes inserting first and second annular liner segments of the liner assembly into a J-groove in a case of the gas turbine engine so as to mount the first and second annular liner segments into the case. A mounting foot of the vane is inserted between the first and second annular liner segments so as to mount the foot of the vane into the J-groove of the case. 
     The method of the preceding paragraph can optionally include, additionally and/or alternatively, any one or more of the following features, configurations and/or additional components. 
     The first annular liner segment can be pressed against a radially outward surface of the mounting foot and against a first surface of the J-groove; and the second annular liner segment can be pressed against a radially inward surface of the mounting foot and against a second surface of the J-groove. 
     The first and second annular liner segments can be configured to move independently of each other. 
     The mounting foot can be circumferentially installed into the J-groove. 
     While the invention has been described with reference to an exemplary embodiment(s), it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment(s) disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.