Patent Publication Number: US-2020300105-A1

Title: Gas turbine engine, corresponding seal section and integrated exit piece

Description:
BACKGROUND 
     1. Field 
     Disclosed embodiments are generally related to gas turbine engines and, more particularly to the transition system of a gas turbine engine. 
     2. Description of the Related Art 
     Gas turbine engines with can annular combustors have transition ducts to conduct and direct the gasses from the combustors to rows of turbine blades. The transition ducts as well as vanes orient the combustion gas flow streams to contact the turbine blades at preferred angles for rotation of the blades. 
     In some gas turbine engines, the transition ducts are arranged in an annular array. The annular array is formed around an inner ring that provides support. Effective sealing between the annular array and the inner ring is desired. 
     SUMMARY 
     Briefly described, aspects of the present disclosure relate to seals used in gas turbine engines. 
     An aspect of the disclosure may be a gas turbine engine having a plurality of integrated exit pieces arranged to form an outer ring, wherein each of the plurality of integrated exit pieces has a first slot formed therein; an inner ring located radially inwards with respect to the plurality of integrated exit pieces, wherein the inner ring has a second slot formed therein. The gas turbine engine may also have a seal section having a first extending portion and a second extending portion, wherein the first extending portion is located in the first slot and the second extending portion is located in the second slot, wherein the first extending portion extends in an axial direction with respect to the outer ring and the second extending portion extends radially inwards with respect to the outer ring, wherein both the first extending portion and the second extending portion extend circumferentially within the first slot and the second slot. 
     Another aspect of the disclosure may be a seal section for use in a gas turbine engine. The seal section may have a first extending portion, wherein the first extending portion is located within a first slot, wherein the first slot is formed within one of a plurality of integrated exit pieces, wherein the plurality of integrated exit pieces form an outer ring; a second extending portion located in a second slot formed in an inner ring, wherein the inner ring is located radially inwards with respect to the outer ring; and wherein the first extending portion extends in an axial direction with respect to the outer ring and the second extending portion extends radially inwards with respect to the outer ring, wherein both the first extending portion and the second extending portion extend circumferentially within the first slot and the second slot. 
     Still another aspect of the disclosure may be an integrated exit piece forming an outer ring in a gas turbine engine having a first slot, wherein the first slot is adapted to receive a seal section for use in a gas turbine engine, wherein the seal section comprises a first extending portion adapted to be located within the first slot, a second extending portion adapted to be located in a second slot formed in an inner ring, wherein the inner ring is located radially inwards with respect to the outer ring; and wherein the first extending portion extends in an axial direction with respect to the outer ring and the second extending portion extends radially inwards with respect to the outer ring, wherein both the first extending portion and the second extending portion extend circumferentially within the first slot and the second slot. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows an integrated exit piece. 
         FIG. 2  shows the integrated exit piece forming an outer ring. 
         FIG. 3  shows an integrated exit piece forming an outer ring connected to an inner ring. 
         FIG. 4  is a view of a first layer of the seal section connected to the integrated exit piece and the inner ring. 
         FIG. 5  is a view of a second layer of the seal section connected to the integrated exit piece and the inner ring. 
         FIG. 6  is a close up view of the anti-rotation structure used with the seal section. 
         FIG. 7  is a view of the first layer of the seal section and the second layer of the seal section showing ship lapping of the first layer and second layer. 
         FIG. 8  is a view of the seal section connecting the inner ring and the outer ring. 
         FIG. 9  is a view of the seal section connecting the inner ring and the outer ring with a view of the slots located in the outer ring and the inner ring. 
     
    
    
     DETAILED DESCRIPTION 
     To facilitate an understanding of embodiments, principles, and features of the present disclosure, they are explained hereinafter with reference to implementation in illustrative embodiments. Embodiments of the present disclosure, however, are not limited to use in the described systems or methods. 
     The components and materials described hereinafter as making up the various embodiments are intended to be illustrative and not restrictive. Many suitable components and materials that would perform the same or a similar function as the materials described herein are intended to be embraced within the scope of embodiments of the present disclosure. 
       FIG. 1  shows an integrated exit piece (IEP)  10  that is used in gas turbine engines. The IEP  10  is connected to a transition duct  8  that transports the gasses from the combustors to rows of turbine blades. Transition ducts as well as vanes orient the combustion gas flow streams to contact the turbine blades at preferred angles for rotation of the blades.  FIG. 2  shows the outer ring  15  that is formed by the connection of more than one IEP  10  to each other. The IEPs  10  are adjacently connected along the circumferential direction C. 
       FIG. 3  shows a partial view the IEPs  10  forming an outer ring  15  connected to an inner ring  16 . The outer ring  15  is located further outwards in the radial direction R than the inner ring  16  from an axis running through the center of the outer ring  15  and the inner ring  16 . 
       FIG. 4  is a view of a first layer  25  of the seal section  20 , shown in  FIG. 5 , that is connected to the IEP  10  and the inner ring  16 . The first layer  25  is shown inserted into a first slot  11  that is located within the IEP  10 . The first layer  25  has a first layer axial section  33  that extends in an axial direction A into the first slot  11 . Connected to the first layer axial section  33  and also forming part of the first layer  25  is a first layer radial section  34  that extends in the radial direction R. The first layer  25  is arced shaped and conforms to the shape of the inner ring  16  and outer ring  15 . 
     First layer  25  extends in a circumferential direction C and has first layer cut outs  28  formed in the first layer radial section  34 . The first layer cut outs  28  are preferably arched shaped so as to accommodate movement of the first layer  25  during operation of the gas turbine engine. In  FIG. 4  the first layer cut outs  28  are spaced equidistantly from each other. However it should be understood that other configurations of the first layer cut outs  28  may be arranged in the first layer radial section  34 . The first layer cut outs  28  further prevent the movement of the first layer  25  in the circumferential direction C when the seal section  20  is fully assembled. 
     First layer  25  forms an arc that extends in the circumferential direction C. The individual first layers  25  may form arcs of between 7.5° to 30° and may vary in number depending on the number of IEPs  10 . Preferably each of the first layers  25  used to form a seal section  20  have the same arc. The arcs of the first layers  25  preferably sum to 360° in order to completely seal the space between the outer ring  15  and the inner ring  16 . 
       FIG. 5  is a view of the second layer  26  of the seal section  20  connected to the IEP  10  and the inner ring  16 . The second layer  26  is shown inserted into a first slot  11  that is located within the IEP  10 . The second layer  26  is arced shaped and conforms to the shape of the inner ring  16  and outer ring  15 , as well as to the shape of the first layer  25 . The second layer  26  has a second layer axial section  35  that extends in the axial direction A into the first slot  11 . Connected to the second layer axial section  35  and also forming part of the second layer  26  is a second layer radial section  36  that extends in the radial direction R. 
     Second layer  26  extends in the circumferential direction C and has second layer cut outs  29  formed in the second layer radial section  36 . Second layer cut outs  29  are preferably arch shaped and also correspond to the shape of the first layer cut outs  28 . In  FIG. 5  the second layer cut outs  29  are spaced equidistantly from each other. However it should be understood that other configurations of the second layer cut outs  29  may be arranged in the second layer radial section  36 . The second layer cut outs  29  are positioned within the second layer  26  so that they correspond to the location of the first layer cut outs  28  located within the first layer  25  when the second layer  26  is positioned on the first layer  25 . 
     Second layer  26  forms an arc that extends in the circumferential direction C. The individual second layers  26  may form arcs of between 7.5° to 30° and may vary in number depending on the number of IEPs  10 . Preferably each of the second layers  26  used to form a seal section  20  have the same arc. The arcs of the second layer  26  preferably sum to 360° in order to completely seal the space between the outer ring  15  and the inner ring  16 . In one embodiment first layer  25  and second layer  26  each forms an arc that is 14.75°. 
       FIG. 6  is a close up view of the anti-rotation structure  30  used with the seal section  20 . The anti rotation structure  30  is located on the inner ring  16 . When the first layer  25  and the second layer  26  are assembled, the first layer cut out  28  of the first layer  25  and the second layer cut out  29  of the second layer  26  align with each other. The aligned first layer cut out  28  and second layer cut out  29  are positioned over the anti rotation structure  30 . As shown, the anti-rotation structure  30  is arched shaped and corresponding to the shapes of the first layer cut out  28  and the second layer cut out  29 . Located within the anti-rotation structure  30  are bolt holes  31 . 
       FIG. 7  is a view of the first layer  25  and the second layer  26  of the seal section  20  showing the shiplap  40  of the first layer  25  and second layer  26 . The shiplap  40  is the interface between the first layer  25  and the second layer  26  where the second layer  26  begins to overlap the first layer  25 . As shown the second layer edge  44  does not extend as far circumferentially as the first layer edge  43 . At opposite ends of the first layer  25  and the second layer  26 , the second layer edge  46  extends further than the first layer edge  45 . The shiplap  40  permits more secure mating of the first layer  25  and the second layer  26  as it extends around the circumference of the outer ring  15  and inner ring  16 . While the first layer edges  43 ,  45  do not align with the second layer edges  44 ,  46  the first layer cut outs  28  and the second layer cut outs  29  do align so as to surround anti-rotation structures  30 . When the first layer  25  and the second layer  26  are shiplapped the first layer  25  and the second layer  26  each forms an arc that is 14.75°. Together the seal section  20  formed by the first layer  25  and the second layer  26  form an arc of 15.75°. The overlapping of the second layer  26  of the first layer  25  may be 0.75°. 
       FIG. 8  is a view of the first layer  25  and the second layer  26  fully assembled and forming the seal section  20 . Upon installing the seal section  20  between the outer ring  15  and the inner ring  16 , a retention plate  17  is secured to the anti-rotation structures  30  using bolts  32  placed through the bolt holes  31 . It should be understood that retention plate  30  may be secured to the anti-rotation structures  30  via other suitable methods, such as brazing or welding. 
     The seal section  20  has a first extending portion  23  formed by the first layer axial section  33  and the second layer axial section  35 . The first extending portion  23  extends in the axial direction A into the first slot  11 . Securing the retention plate  17  forms a second slot  12 . The second slot  12  receives the second extending portion  24  of the seal section  20  which extends in the radial direction R into the second slot  12 . The second extending portion  24  is formed by the first layer radial section  34  and second layer radial section  36 . 
     As shown in  FIG. 8 , the first extending portion  23  and the second extending portion  24  form an L-shaped cross section. Referring to  FIG. 9 , while the L-shaped cross-section is L-shaped it should be understood that the angle α formed at the location where the first extending portion  23  and the second extending portion  24  meet, it is not necessarily 90°. Instead the angle α may be within a range of 80° to 100° in order to accommodate the curvature of the seal section  20 . Further, other configurations other than L-shaped are possible, for example a C-shape, V-shaped, or obtuse angle shape may also be formed. 
       FIG. 9  also shows a view of the seal section  20  connecting the inner ring  16  and the outer ring  15  with a close-up view of the first slot  11  and second slot  12  located in the outer ring  15  and the inner ring  16 . 
       FIG. 9  illustrates that the first extending portion  23  does not extend fully into the first slot  11 . There is still space in the axial direction A in which the first extending portion  23  may move axially. The range in which the first extending portion  23  may move is sufficient to accommodate the stresses and deformations that may occur during the operation of the gas turbine engine. The deformations and stresses can be accommodated while the seal section  20  continues to seal the space between the outer ring  15  and inner ring  16 . Additionally the first slot  11  has sufficient space to permit the first extending portion  23  to move in the radial direction R in order to accommodate stresses and deformations that may occur during the operation of the gas turbine engine. 
       FIG. 9  also shows that the second extending portion  24  does not extend fully into the second slot  12 . There is still space in the radial direction R in which the second extending portion  24  may move radially. The range in which the second extending portion  24  may move is sufficient to accommodate the stresses and deformations that may occur during the operation of the gas turbine engine. The deformations and stresses can be accommodated while the seal section  20  continues to seal the space between the outer ring  15  and inner ring  16 . Additionally the second slot  12  has sufficient space to permit the second extending portion  24  to move in the axial direction A in order to accommodate stresses and deformations that may occur during the operation of the gas turbine engine. 
     Additionally, the ability for each seal section  20  to move in the radial direction R and the axial direction A permits each seal section  20  to be able to move with respect to each other. This permits greater flexibility for the stresses and deformations to be compensated for without jeopardizing the integrity of the seal section  20 . 
     While embodiments of the present disclosure have been disclosed in exemplary forms, it will be apparent to those skilled in the art that many modifications, additions, and deletions can be made therein without departing from the spirit and scope of the invention and its equivalents, as set forth in the following claims.