The present disclosure relates generally to airfoil assemblies for gas turbine engines, and more specifically to airfoils that comprise ceramic-containing materials.
Gas turbine engines are used to power aircraft, watercraft, power generators, and the like. Gas turbine engines typically include a compressor, a combustor, and a turbine. The compressor compresses air drawn into the engine and delivers high pressure air to the combustor. In the combustor, fuel is mixed with the high pressure air and is ignited. Products of the combustion reaction in the combustor are directed into the turbine where work is extracted to drive the compressor and, sometimes, an output shaft. Left-over products of the combustion are exhausted out of the turbine and may provide thrust in some applications.
Products of the combustion reaction directed into the turbine flow over airfoils included in stationary vanes and rotating blades of the turbine. The interaction of combustion products with the airfoils heats the airfoils to temperatures that require the airfoils to be made from high-temperature resistant materials and/or to be actively cooled by supplying relatively cool air to the vanes and blades. To this end, some airfoils for vanes and blades are incorporating composite materials adapted to withstand very high temperatures. Design and manufacture of vanes and blades from composite materials presents challenges because of the geometry and strength limitations of composite materials.
The present disclosure may comprise one or more of the following features and combinations thereof.
An airfoil assembly for a gas turbine engine may include a ceramic matrix composite vane, a metallic support spar, and a metallic sleeve. The ceramic matrix composite vane may be adapted to interact with hot gases flowing through a gas path of the gas turbine engine during use of the airfoil assembly. The metallic support spar may extend axially through an interior cavity formed in the ceramic matrix composite vane. The metallic sleeve may be configured to receive force loads applied to the ceramic matrix composite vane by the hot gases during use of the airfoil assembly.
In some embodiments, the ceramic matrix composite vane may include an outer platform, an inner platform, an airfoil, and an outer vane mount. The outer platform may define an outer boundary of the gas path. The inner platform may be spaced apart axially from the outer platform relative to an axis to define an inner boundary of the gas path. The airfoil may extend axially between and interconnect the outer platform and the inner platform. The outer vane mount may extend axially outward away from the outer platform. In some embodiments, the metallic sleeve may be located axially outward of the outer platform outside of the gas path.
In some embodiments, the metallic sleeve may include a sleeve body and a first load-transfer tab. The metallic sleeve may be arranged around the outer vane mount of the ceramic matrix composite vane and the metallic support spar. The first load-transfer tab may extend from the sleeve body toward the outer vane mount of the ceramic matrix composite vane and engage the outer vane mount to transmit the force loads from the ceramic matrix composite vane to the metallic sleeve.
In some embodiments, the outer vane mount includes an inner surface and an outer surface. The inner surface may define a portion of the interior cavity. The outer surface may be opposite the inner surface. In some embodiments, the first load-transfer tab may be engaged with the outer surface of the outer vane mount.
In some embodiments, the ceramic matrix composite vane may have a leading edge, a trailing edge, a pressure side, and a suction side. In some embodiments, the first load-transfer tab may be engaged with the outer surface of the outer vane mount on the suction side of the ceramic matrix composite vane.
In some embodiments, the metallic sleeve may further include a second load-transfer tab. The second load-transfer tab may be configured to engage the outer surface of the outer vane mount on the pressure side of the ceramic matrix composite vane.
In some embodiments, the airfoil assembly may further include a bias member. The bias member may be configured to urge the outer vane mount and the metallic sleeve toward each other on the suction side of the ceramic matrix composite vane. In some embodiments, the bias member may be located in the interior cavity between the outer vane mount and the metallic sleeve on the pressure side of the ceramic matrix composite vane.
In some embodiments, the bias member may include a clip. The clip may receive a portion of the outer vane mount and a portion of the metallic sleeve in the clip. In some embodiments, the clip may be located on the suction side of the ceramic matrix composite vane.
In some embodiments, the bias member may include a clip. The clip may be fixed with the metallic sleeve on the suction side of the metallic sleeve. In some embodiments, the clip may receive an axial terminating end of the outer vane mount.
In some embodiments, the airfoil assembly may further include a fastener. The fastener may extend into the outer vane mount and at least one of the sleeve body and the metallic support spar to engage the outer vane mount with the first load-transfer tab.
According to another aspect of the disclosure, an airfoil assembly may include a vane and a sleeve. The vane may include an outer platform, an inner platform, an airfoil, and an outer vane mount. The inner platform may be spaced apart axially from the outer platform relative to an axis. The airfoil may extend axially between and interconnect the outer platform and the inner platform. The outer vane mount may extend axially outward away from the outer platform. The sleeve may include a sleeve body arranged around the outer vane mount of the vane and a load-transfer tab that engages the outer vane mount.
In some embodiments, the outer vane mount may include an inner surface and an outer surface. The inner surface may define a portion of an interior cavity that extends axially into the vane. The outer surface may be opposite the inner surface.
In some embodiments, the load-transfer tab may be engaged with the outer surface of the outer vane mount. In some embodiments, the load-transfer tab may be engaged with the inner surface of the outer vane mount.
In some embodiments, the airfoil assembly may further include a bias member. The bias member may be located in the interior cavity between the outer vane mount and the sleeve.
In some embodiments, the vane may have a leading edge, a trailing edge, a pressure side, and a suction side. In some embodiments, the load-transfer tab may be engaged with the outer vane mount on the suction side of the vane.
In some embodiments, the airfoil assembly may further include a bias member. The bias member may be configured to urge the outer vane mount and the sleeve toward each other.
In some embodiments, the vane may have a leading edge, a trailing edge, a pressure side, and a suction side. In some embodiments, the bias member may be located between the outer vane mount and the sleeve on the pressure side of the vane.
In some embodiments, the bias member may include a clip. The clip may receive a portion of the outer vane mount and a portion of the sleeve in the clip.
In some embodiments, the bias member may include a clip. The clip may be fixed with the sleeve on the suction side of the sleeve. The clip may receive an axial terminating end of the outer vane mount.
According to another aspect of the disclosure, a method may include providing a vane and a sleeve. The vane may include an outer platform, an inner platform spaced apart axially from the outer platform relative to an axis, an airfoil that extends axially between and interconnects the outer platform and the inner platform, and an outer vane mount that extends axially outward away from the outer platform. The sleeve may include a sleeve body and a load-transfer tab that extends away from the sleeve body.
The method may further include arranging the sleeve around the outer vane mount to locate the sleeve axially outward of the outer platform, engaging the outer vane mount with the load-transfer tab of the sleeve. In some embodiments, and biasing the outer vane mount and the load-transfer tab toward one another. In some embodiments, the load-transfer tab may be located on a suction side of the vane.
These and other features of the present disclosure will become more apparent from the following description of the illustrative embodiments.
For the purposes of promoting an understanding of the principles of the disclosure, reference will now be made to a number of illustrative embodiments illustrated in the drawings and specific language will be used to describe the same.
An airfoil assembly 10 according to the present disclosure and adapted for use in a gas turbine engine is shown in
The vane 12 comprises ceramic matrix materials while the support spar 14 and sleeve 16 comprise metallic materials in the illustrative embodiment. The ceramic matrix composite vane 12 is adapted to withstand high temperatures, but may have relatively low strength compared to the metallic support spar 14. The metallic support spar 14 provides structural strength to the assembly 10 by receiving the force loads applied to the other components of the gas turbine engine. However, the metallic support spar 14 may not be capable of withstanding the high temperatures experienced by the ceramic matrix composite vane 12. As such, the metallic support spar 14 may have a coefficient of thermal expansion greater than that of the ceramic vane 12.
Due to the difference in coefficients of thermal expansion and structural strength between the ceramic matrix composite materials of the vane 12 and the metallic materials of the support spar 14, transferring loading of the vane 12 to the support spar 14 may be difficult. The sleeve 16 is configured to receive the force loads applied to the vane 12, while controlling the orientation of the vane 12 relative to the support spar 14 to define a determinate load transfer from the vane 12 to the sleeve 16 out through the supporting structure. In some embodiments, the supporting structure may be an outer mount support 15 or a turbine case 17 of the gas turbine engine as suggested in
The ceramic matrix composite vane 12 includes an outer platform 24, an inner platform 26, an airfoil 28, and an outer vane mount 30 as shown in
Illustratively, the outer platform 24, the inner platform 26, the airfoil 28, and the outer vane mount 30 are integrally formed to provide a single-piece, unitary component. In other embodiments, the vane 12 may be formed from a number of separate components. In other embodiments, the vane 12 may comprise metal, composite, ceramic, or ceramic matrix composite materials.
The vane 12 also has a leading edge 36, a trailing edge 38, a suction side 40, and pressure side 42 as shown in
The outer vane mount 30 includes an inner surface 44 and an outer surface 46 as shown in
The metallic sleeve 16 includes a sleeve body 50 and load-transfer tabs 52 as shown in
The sleeve body 50 includes an inner sleeve surface 54 and an outer sleeve surface 56 as shown in
The load-transfer tabs 52 include at least two load-transfer tabs 62, 64 as shown in
In the illustrative embodiment, the load-transfer tabs 52 include at least three load-transfer tabs 62, 64, 66. The first and third load-transfer tabs 62, 66 are engaged with the outer surface 46 of the outer vane mount 30 on the suction side 40 of the vane 12, while the second load-transfer tab 64 is engaged with the pressure side 42 of the vane 12. In other embodiments, the load-transfer tabs 52 may include more than three load-transfer tabs 52.
During use of the airfoil assembly 10, the force loads acting on the vane 12 from the hot gases apply a force against the pressure side 42 of the airfoil 28. The force against the pressure side 42 urges the vane 12 toward and into engagement with the load-transfer tabs 62, 66 located on the suction side 40. The load-transfer tabs 62, 66 limit the amount of movement the vane 12 may experience and receive the force loads acting on the vane 12. The load-transfer tabs 62, 66 transmit the loads to the turbine case 17 or mount features 15. In the illustrative embodiment, the load-transfer tabs 52 engage with the outer surface 46 of the outer vane mount 30 to receive the force loads from the vane 12. In other embodiments, the load-transfer tabs 52 may engage with the inner surface 44 of the outer vane mount 30 to receive the force loads from the vane 12.
In the illustrative embodiment, the second load-transfer tab 64 is configured to act as a retention feature that may help control the orientation of the vane 12 during off-loading conditions or surge of the engine. In some embodiments, the second load-transfer tab 64 may not engage the outer surface 46 of the outer vane mount 30 during use of the airfoil assembly 10.
In the illustrative embodiment, the metallic sleeve 16 is configured to be coupled to the outer mount support 15 as suggested in
Turning again to the metallic support spar 14, the metallic support spar 14 may be coupled to an inner stage seal of the gas turbine engine. The support spar 14 may be configured to transfer axial loads from the inner stage seal axially outwards to the casing 17.
Another embodiment of an airfoil assembly 210 in accordance with the present disclosure is shown in
The airfoil assembly 210 includes a ceramic matrix composite vane 212, a metallic support spar 214, a metallic sleeve 216, and a bias member 218 as shown in
The ceramic matrix composite vane 212 includes an outer platform 224, an inner platform 226, an airfoil 228, and an outer vane mount 230 as shown in
The vane 212 further includes a leading edge 236, a trailing edge 238, a suction side 240, and pressure side 242 as shown in
The outer vane mount 230 includes an inner surface 244 and an outer surface 246 as shown in
The metallic sleeve 216 includes a sleeve body 250 and a load-transfer tab 252 as shown in
The sleeve body 250 includes an inner sleeve surface 254 and an outer sleeve surface 256 as shown in
The inner sleeve surface 254 is also shaped to define a bias member locating notch 258 as shown in
In the illustrative embodiment, the load-transfer tab 252 extends from the inner sleeve surface 254 and engages the outer surface 246 of the outer vane mount 230. The load-transfer tab 252 is a continuous rail that extends from the inner sleeve surface 254 and engages the outer surface 246 of the vane 212 along the suction side 240 of the vane 212. In some embodiments, the metallic sleeve 216 may include a plurality of load-transfer tabs 252 that engage the outer surface 246 of the outer vane mount 230 along the suction side 240 of the vane 212.
In some embodiments, the metallic sleeve 216 includes at least two load-transfer tabs 262, 264 as shown in
In the illustrative embodiment of
In both illustrative embodiments of
In the illustrative embodiment, the bias member 218 is a wave spring. In other embodiments, the bias member may be a compliant layer, a spring, or another suitable biasing element. In other embodiments, the airfoil assembly 210 may include a plurality of bias members 216 spaced apart along the perimeter of the pressure side 242 of the vane 212.
Another embodiment of an airfoil assembly 310 in accordance with the present disclosure is shown in
The airfoil assembly 310 includes a ceramic matrix composite vane 312, a metallic support spar 314, a metallic sleeve 316, and a bias member 318 as shown in
The ceramic matrix composite vane 312 includes an outer platform 324, an inner platform 326, an airfoil 328, and an outer vane mount 330 as shown in
The metallic sleeve 316 includes a sleeve body 350 and load-transfer tabs 352 as shown in
The sleeve body 350 includes an inner sleeve surface 354 and an outer sleeve surface 356 as shown in
The load-transfer tabs 352 include a first load-transfer tab 362 and a second load-transfer tab 364 as shown in
In the illustrative embodiment, the load-transfer tabs 352 are continuous rails that extend along and engage a suction side 340 of the vane 312 on the outer vane mount 330. In some embodiments, the load-transfer tabs 352 may be a plurality of tabs 352 that are spaced apart from each other along the suction side 340 of the vane 312. In other embodiments, the load-transfer tabs 352 may be a plurality of tabs 352 that are spaced apart axially along the sleeve body 350.
The bias member 318 includes a clip 370 as shown in
In the illustrative embodiment, the airfoil assembly 310 further includes the seal element 372 as shown in
In the illustrative embodiment, the seal element 372 is a rope seal. In other embodiments, the seal element 372 may be another suitable seal.
The clip 370 includes a locating end 374, a curved biasing portion 376, and a clip head 378 as shown in
In the illustrative embodiment, the clip 370 receives an axial terminating end 380 of the outer vane mount 330 and an axial terminating end 382 of the sleeve body 350 as shown in
In the illustrative embodiment, the airfoil assembly 310 includes a plurality of clips 370 as shown in
In some embodiments, the airfoil assembly 310 may include a single clip 370 with a locating end 374 and a plurality of clip heads 376, 378. The locating end 374 may extend along the suction side 340 of the vane 312 and the plurality of clip heads 376, 378 may be spaced apart along the suction side 340 of the vane 312 and each extend from the locating end 474 around a portion of the vane 312.
In some embodiments, the support spar 314 may couple with the outer mount support to couple the support spar 314 to the case 19. The outer mount support may include a wall located radially outward of the clip 370. The wall, along with the notch 358, may help locate the clip 370. In some embodiments, the wall may be configured to maintain the engagement of the clip 370 with the vane 312 and the support spar 314 by blocking the clip 370 from backing off the components during operation of the engine.
Another embodiment of an airfoil assembly 410 in accordance with the present disclosure is shown in
The airfoil assembly 410 includes a ceramic matrix composite vane 412, a metallic support spar 414, a metallic sleeve 416, and a bias member 418 as shown in
The ceramic matrix composite vane 412 includes an outer platform 424, an inner platform 426, an airfoil 428, and an outer vane mount 430 as shown in
The outer vane mount 430 includes an inner surface 444, an outer surface 446, and a bias member locating notch 448 as shown in
The metallic sleeve 416 includes a sleeve body 450 and load-transfer tabs 462, 464 as shown in
The sleeve body 450 includes an inner sleeve surface 454 and an outer sleeve surface 456 as shown in
The load-transfer tabs 462, 464 include a first load-transfer tab 462 and a second load-transfer tab 464 as shown in
The bias member 418 includes a clip 470 as shown in
In the illustrative embodiment, the load-transfer tabs 462, 464 extend along and engage the suction side 440 of the outer vane mount 430. The clip 470 is located on the suction side 440 of the ceramic matrix composite vane 412 to maintain engagement of the load-transfer tabs 462, 464 on the suction side 440 of the vane 412.
The clip 470 includes a locating end 474, a curved biasing portion 476, and a clip head 478 as shown in
In the illustrative embodiment, the locating end 474 is brazed or welded to the inner sleeve surface 454 of the sleeve body 50. In other embodiments, the locating end 474 may be attached using another suitable method.
In the illustrative embodiment, the airfoil assembly 410 includes a plurality of bias members 418 or clips 470 as shown in
In some embodiments, the airfoil assembly 410 may include a single clip 470 with a locating end 474 and a plurality of clip heads 476, 478. The locating end 474 may extend along the suction side 440 of the vane 412 and the plurality of clip heads 476, 478 may be spaced apart along the suction side 440 of the vane 412 and each extend from the locating end 474 around a portion of the vane 412.
Another embodiment of an airfoil assembly 510 in accordance with the present disclosure is shown in
The airfoil assembly 510 includes a ceramic matrix composite vane 512, a metallic support spar 514, a metallic sleeve 516, a bias member 518, and a fastener 520 as shown in
The ceramic matrix composite vane 512 includes an outer platform 524, an inner platform 526, an airfoil 528, and an outer vane mount 530 as shown in
The outer vane mount 530 includes an inner surface 544 and an outer surface 546 as shown in
The metallic sleeve 516 includes a sleeve body 550 and a load-transfer tab 552 as shown in
In the illustrative embodiment, the bias member 518 is located in a portion of the interior cavity 522 defined by the outer vane mount 530 as shown in
In the illustrative embodiment, the bias member 518 is a compliant member 518 as shown in
In other embodiments, the bias member 518 may be made of a material with a higher coefficient of thermal expansion than the fastener 520. By setting the length of the member 518 appropriately, the thermal expansion of the member 518 may be matched by the undergrowth of the ceramic vane 512 such that compression in the bolted joint may be maintained throughout operation. For instance, the member 518 may be made of STELLITE® 31 in such embodiments.
The fastener 520 includes a head 584 and a pin 586 as shown in
In the illustrative embodiment, the head 584 of the fastener 520 is a bolt head 584 as shown in
In some embodiments, the support spar 514 may be hollow and the pin 586 of the fastener 520 may extend through a hole formed in the support spar 514 into the hollow cavity extending axially through the support spar 514. The pin 586 may be retained to the support spar 514 by a retaining ring, cotter key, or another suitable retaining device attached to the end of the pin 586 extending through the hole. In other embodiments, the fastener 520 may only include the pin 586 having threads 590 at both ends that mate with corresponding threads in the metallic sleeve 516 and the metallic support spar 514.
The present disclosure relates to load transferring of an airfoil assembly 10, 210, 310, 410, 510 within a gas turbine engine. Specifically, the present disclosure teaches transferring loads from a ceramic matrix composite (CMC) turbine vane 12, 212, 312, 412, 512 to a metallic support structure 14, 214, 314, 414, 514.
As there may be a significant difference in the coefficient of thermal expansion between ceramic matrix composite materials and high temperature metals, the metallic support spar 14, 214, 314, 414, 514 may outgrow or expand more than the ceramic matrix composite vane 12, 212, 312, 412, 512. This difference in thermal expansion may not allow for clamping arrangements of the airfoil assembly 10, 210, 310, 410, 510.
Due to the low strength capability of the ceramic matrix composite materials, applying significant pre-load to the ceramic matrix composite materials of the airfoil assembly 10, 210, 310, 410, 510 may be difficult. The low strength capability and the relatively high stiffness of the ceramic matrix composite materials may also make transferring loading of the vane 12, 212, 312, 412, 512 difficult. For instance, typical load-transfer features may not be able to conform to the ceramic matrix composite airfoil shape and offer distributed loading.
As a solution, the present disclosure teaches discrete load-transfer features or load-transfer tabs 52, 252, 352, 462, 464, 552 on a metallic sleeve 16, 216, 316, 416, 516 as shown in
An embodiment of the airfoil assembly 10 is shown in
In the illustrative embodiment, the load-transfer tabs 52 are a hard-stop, pad, or datum 62, 64, 66. The datums 62, 64, 66 locate the ceramic matrix composite component 12 and transmit the aerodynamic forces. In the illustrative embodiment, the load-transfer tabs 62, 66 are arranged on the suction side 40 of the vane 12, while the other load-transfer tab 64 is arranged on the pressure side 42 of the vane 12. The load-transfer tab 64 is located on the pressure side 42 of the vane 12 acts as a retention feature 64 to prevent gross movement of the ceramic matrix composite component 12 during off-design conditions and to limit movement of the vane 12 during surge event.
In the illustrative embodiment of
The load-transfer features 52, 252, 352, 462, 464, 552 may also be configured to engage the vane 12, 212, 312, 412, 512 across a typical flight cycle so that the orientation of the aerodynamic load applied to a vane 12, 212, 312, 412, 512 does not dramatically change. As such, under load the ceramic matrix composite vane 12, 212, 312, 412, 512 may be biased towards the load-transfer features 52, 252, 352, 462, 464, 552 in a similar direction but with varying magnitude.
Under extreme operating conditions, such as engine surge, the orientation of the aerodynamic load may shift. At engine shutdown or when the vane 12, 212, 312, 412, 512 is un-loaded, the ceramic matrix composite vane 12, 212, 312, 412, 512 may then be unsupported and due to the circumferential distribution of the components around the engine. All parts may likely unload in different directions and with varying magnitudes.
To prevent unloading, the ceramic matrix composite vane 212, 312, 412, 512 may be biased towards the datum features 262, 264, 362, 364, 462, 464 such that the ceramic matrix composite vane 212, 312, 412, 512 retain position when the vane 212, 312, 412, 512 is unloaded. The magnitude of this pre-load may be greater than the inertia of the ceramic matrix composite vane 212, 312, 412, 512 under typical engine-unpowered vibration, airframe operating loads, and/or landing loads. The pre-load may be no greater than this value as it must be in the direction of the aerodynamic load and may add to that load vector. In the illustrative embodiments, the airfoil assemblies 210, 310, 410510 each include load-transfer features and variations of the pre-load feature.
In the illustrative embodiment of
However, there may be some advantages to arranging the load pads 62, 64, 66 on the outer surface 46 of the vane 12. Arranging the load pads 62, 64, 66 on the outer surface 46 of the vane 12 may alleviate concerns of greater thermal growth of the metallic sleeve 16, which may cause tensile hoop stresses in the ceramic matrix composite vane 12. Additionally, arranging the load pads 62, 64, 66 on the outer surface 46 of the vane 12 may allow all internal vane cavity space 22 to be utilized by the support spar 14, thus producing a stiffer structure for supporting the inter stage seal load from the inner stage seal.
In the illustrative embodiments, the bias member 218, 318, 418, 518 may be configured to bias the load pads 252, 352, 462, 464, 552 and the outer vane mount 230, 330, 430, 530 of the vane 212, 312, 412, 512 toward each other at cold conditions, but also configured to minimize the load at high temperatures. Minimizing the bias force or pre-load at high temperatures may reduce the stress in the vane 212, 312, 412, 512. Biasing the load pads 252, 352, 462, 464, 552 may also improve the creep performance of the airfoil assembly 210, 310, 410, 510, as the creep rate may be proportional to the load/stress within the part and hence, should reduce with temperature.
In the illustrative embodiments, positioning the bias member 218, 318, 418, 518 outboard of the hot gas path region 13 may reduce the temperature of the bias member 218, 318, 418, 518 so as to avoid excessive creep and stress relaxation. Additionally, locating the bias member 218, 318, 418, 518 outside the gas path 13 may allow for cooling the features as necessary.
Also, the high level of thermal radiation within the inside of the ceramic matrix composite vane 12, 212, 312, 412, 512 in the hot gas path region 13, along with the minimal space, may limit the ability to apply cooling or apply heat shielding to the features. However, outside of the gas path 13, the amount of available space to apply cooling air or heat shield may be greater. In addition, the radiation loading of heat onto the features may be drastically lower outside of the gas path 13.
In the illustrative embodiment of
In the illustrative embodiment of
The clips 370 may be retained by spring forces encouraging interference features into receiving features on the metallic sleeve 316. In the illustrative embodiment of
In the illustrative embodiment, the airfoil assembly 310 may further include a seal element 372 as shown in
In the illustrative embodiment, the load-transfer tabs 362, 364 may be continuous rails oriented substantially in the perimeter direction as oriented to the ceramic matrix composite attachment feature or outer vane mount 330. In other embodiments, the tabs 362, 364 may be discontinuous bumps/protrusions.
In the illustrative embodiment of
In the illustrative embodiment of
The fastener 520 may be assembled through a hole in the ceramic matrix composite vane 512 and attached to the metallic support spar 514. This fastener 520 may be threaded 590 on one or both ends 588 and may pass through a hole in the metallic support spar 514. The fastener 520 may be blocked from removal from the hole by a retaining ring, cotter key, or other such retaining device.
The bias member or resilient component 518 may be located between the outer surface 546 of the ceramic matrix composite vane 512 and the end 588 of the fastener 520. In some embodiments, the resilient layer 518 may be a high temperature nickel alloy Belleville washer, a high temperature nickel alloy wave washer, or a high temperature gasket material such as THERMICULITE® or mica board (metal foil encapsulated or not).
In the illustrative embodiment, a feature 584 at the external end of the fastener 520 may be fixed to the pin 586 and may compress and contain the resilient component 518. This feature 584 may be a head 584 on the pin 586 (similar to a bolt head), a nut, or a separate washer type piece with a slip fit over the pin 586. If a separate washer is utilized, a retention feature such as a retaining ring, cotter key, or integral features may be used allow pressed assembly, but also resist movement in the opposite direction. If a washer and retaining ring type retention is utilized, a shim washer(s) may be used to set the compression of the resilient component 518.
An optional feature may be a spacer. The spacer may allow the bias member 518 to be compressed only to a height set by the spacer. Such a spacer may be a separate piece or integral with the spring retention piece 518 or integral with the outer vane mount 530 of the ceramic matrix composite component 512.
While the disclosure has been illustrated and described in detail in the foregoing drawings and description, the same is to be considered as exemplary and not restrictive in character, it being understood that only illustrative embodiments thereof have been shown and described and that all changes and modifications that come within the spirit of the disclosure are desired to be protected.