US-20260125990-A1 - EXPANSION JOINT FOR GAS TURBINE EXHAUST SYSTEM

US20260125990A1US 20260125990 A1US20260125990 A1US 20260125990A1US-20260125990-A1

Abstract

An expansion joint for a gas turbine exhaust system includes arcuate expansion joint segments that include a rigid seal plate having an inner radial end and an outer radial end. A first pivot coupler pivotally couples the inner radial end of the rigid seal plate to the turbine duct flange, and a second pivot coupler pivotally couples the outer radial end of the rigid seal plate to the diffuser duct flange. The pivot couplers include a mount member fixedly coupled to a respective duct flange and pivotally engaging a first axial side of the rigid seal plate, a clamp member pivotally engaging a second axial side of the rigid seal plate opposite the first axial side of the rigid seal plate, and actuator(s) configured to press a respective radial end of the rigid seal plate between the clamp member and the mount member.

Inventors

Javeed Iqbaluddin Mohammed
Bradly Aaron Kippel

Assignees

GE INFRASTRUCTURE TECHNOLOGY LLC

Dates

Publication Date: 20260507
Application Date: 20241101

Claims (20)

1 . An expansion joint for use between a turbine duct flange and a diffuser duct flange of a gas turbine exhaust system, the expansion joint comprising: a plurality of arcuate expansion joint segments configured to be arranged circumferentially to collectively form an annular expansion joint assembly, the plurality of arcuate expansion joint segments each including: a rigid seal plate having an inner radial end and an outer radial end; a first pivot coupler pivotally coupling the inner radial end to the turbine duct flange; and a second pivot coupler pivotally coupling the outer radial end to the diffuser duct flange, wherein each of the first and second pivot couplers includes: a mount member fixedly coupled to a respective duct flange and pivotally engaging the rigid seal plate; a clamp member pivotally engaging the rigid seal plate; and at least one actuator configured to press a respective radial end of the rigid seal plate between the clamp member and the mount member.
2 . The expansion joint of claim 1 , wherein the at least one actuator includes: a post fixedly coupled at one end thereof to a respective duct flange and extending through a first opening in the mount member, a second opening in a respective radial end of the rigid seal plate, and a third opening in the clamp member; a force applicator operatively coupled to the post; and a holder coupled to the post and engaging the force applicator, wherein the force applicator forces the clamp member and the respective radial end of the rigid seal plate against the mount member.
3 . The expansion joint of claim 2 , wherein the second opening in the inner radial end of the rigid seal plate includes a through-hole extending through the rigid seal plate, and the second opening in the outer radial end of the rigid seal plate includes a slot extending through the rigid seal plate and open to a radial outer edge of the rigid seal plate.
4 . The expansion joint of claim 2 , further comprising at least one post-interface seal plate engaging an axial side of the rigid seal plate between the rigid seal plate and one of the mount member and the clamp member adjacent the second opening at a respective radial end of the rigid seal plate, the at least one post-interface seal plate including at least one third opening through which a respective post extends, wherein the at least one third opening is smaller than the second opening adjacent thereto in the rigid seal plate.
5 . The expansion joint of claim 4 , wherein the at least one post-interface seal plate includes: a first pair of post-interface seal plates at the outer radial end of the rigid seal plate, the first pair of post-interface seal plates including a first post-interface seal plate engaging a first axial side of the rigid seal plate between the rigid seal plate and the mount member and a second post-interface seal plate engaging a second axial side of the rigid seal plate between the rigid seal plate and the clamp member; a second pair of post-interface seal plates at the inner radial end of the rigid seal plate, the second pair of post-interface seal plates including a third post-interface seal plate engaging the second axial side of the rigid seal plate between the rigid seal plate and the mount member and a fourth post-interface seal plate engaging the first axial side of the rigid seal plate between the rigid seal plate and the clamp member; or both the first pair of post-interface seal plates and the second pair of post-interface seal plates.
6 . The expansion joint of claim 4 , wherein the rigid seal plate includes opposing circumferential ends configured to mate with an adjacent rigid seal plate of an adjacent arcuate expansion joint segment, and further comprises at least one segment end interface seal plate extending across a gap extending from the outer radial end to the inner radial end at adjacent circumferential ends of arcuately adjacent rigid seal plates, each segment end interface seal plate engaging an axial side of the arcuately adjacent rigid seal plates and including at least one third opening through which a respective post extends, wherein the third opening is smaller than the second opening adjacent thereto in the rigid seal plate.
7 . The expansion joint of claim 6 , wherein circumferential ends of the at least one segment end interface seal plate and circumferential ends of the at least one post-interface seal plate include mating male-female couplers.
8 . The expansion joint of claim 2 , wherein the force applicator includes a compression spring selected from a group comprising a coil spring and a cone frustum spring.
9 . The expansion joint of claim 2 , wherein the post is outwardly threaded along at least a portion thereof, and the holder is threadedly adjustably coupled to the at least portion of the post.
10 . The expansion joint of claim 1 , wherein in a cold operating state of the gas turbine exhaust system, the inner radial end of the rigid seal plate is axially forward of the outer radial end of the rigid seal plate, and in a hot operating state of the gas turbine exhaust system the inner radial end of the rigid seal plate is axially rearward of the outer radial end of the rigid seal plate.
11 . The expansion joint of claim 1 , wherein the mount member and the clamp member are both substantially hemispherical.
12 . The expansion joint of claim 11 , wherein the mount member and the clamp member are halves of a cylindrical pipe.
13 . The expansion joint of claim 1 , wherein the rigid seal plate includes a male-female coupler on circumferential ends thereof configured to mate with a circumferentially adjacent rigid seal plate.
14 . The expansion joint of claim 1 , further comprising a wire mesh seal member filling a gap between an adjacent duct flange, the clamp member, and the mount member.
15 . The expansion joint of claim 1 , wherein the rigid seal plate, the clamp member, and the mount member include a stainless steel.
16 . An expansion joint for use between a turbine duct flange and a diffuser duct flange of a gas turbine exhaust system, the expansion joint comprising: a plurality of arcuate expansion joint segments configured to be arranged collectively to form an annular expansion joint assembly, each arcuate expansion joint segment including: a rigid seal plate having an inner radial end, an outer radial end, a through-hole extending through the inner radial end of the rigid seal plate, and a slot extending through the outer radial end of the rigid seal plate and open to a radial outer edge of the rigid seal plate; a first pivot coupler pivotally coupling the inner radial end of the rigid seal plate to the turbine duct flange, the first pivot coupler including: a first mount member fixedly coupled to the turbine duct flange and pivotally engaging a first axial side of the rigid seal plate, a first clamp member pivotally engaging a second axial side of the rigid seal plate opposite the first axial side of the rigid seal plate, and at least one first actuator including: a first post fixedly coupled at one end thereof to the turbine duct flange and extending through a first opening in the first mount member, the through-hole in the inner radial end of the rigid seal plate, and a second opening in the first clamp member; and a first force applicator operatively coupled to the first post and configured to force the first clamp member and the inner radial end of the rigid seal plate against the first mount member; and a second pivot coupler pivotally coupling the outer radial end of the rigid seal plate to the diffuser duct flange, the second pivot coupler including: a second mount member fixedly coupled to the diffuser duct flange and pivotally engaging the second axial side of the rigid seal plate, a second clamp member pivotally engaging the first axial side of the rigid seal plate, and at least one second actuator including: a second post fixedly coupled at one end thereof to the diffuser duct flange and extending through a third opening in the second mount member, the slot in the outer radial end of the rigid seal plate, and a fourth opening in the second clamp member; and a second force applicator operatively coupled to the second post and configured to force the second clamp member and the outer radial end of the rigid seal plate against the second mount member.
17 . The expansion joint of claim 16 , further comprising: a first pair of post-interface seal plates at the outer radial end of the rigid seal plate, the first pair of post-interface seal plates including a first post-interface seal plate engaging the first axial side of the rigid seal plate between the rigid seal plate and the first mount member and a second post-interface seal plate engaging the second axial side of the rigid seal plate between the rigid seal plate and the first clamp member at the outer radial end of the rigid seal plate; a second pair of post-interface seal plates at the inner radial end of the rigid seal plate, the second pair of post-interface seal plates including a third post-interface seal plate engaging the first axial side of the rigid seal plate between the rigid seal plate and the second clamp member and a fourth post-interface seal plate engaging the second axial side of the rigid seal plate between the rigid seal plate and the second mount member; or both the first pair of post-interface seal plates and the second pair of post-interface seal plates.
18 . The expansion joint of claim 16 , wherein the rigid seal plate includes opposing circumferential ends configured to mate with an adjacent rigid seal plate of an adjacent arcuate expansion joint segment, and further comprises at least one segment end interface seal plate extending across a gap extending from the outer radial end to the inner radial end at adjacent circumferential ends of arcuately adjacent rigid seal plates, the at least one segment end interface seal plate engaging one of the first axial side and the second axial side of the arcuately adjacent rigid seal plates and including at least one fifth opening through which a respective post extends, wherein the fifth opening is smaller than the through-hole or the slot adjacent thereto in the rigid seal plate.
19 . The expansion joint of claim 16 , wherein the first and second mount members and the first and second clamp members are substantially hemispherical.
20 . The expansion joint of claim 16 , wherein in a cold operating state of the gas turbine exhaust system, the inner radial end of the rigid seal plate is axially forward of the outer radial end of the rigid seal plate, and in a hot operating state of the gas turbine exhaust system the inner radial end of the rigid seal plate is axially rearward of the outer radial end of the rigid seal plate.

Description

TECHNICAL FIELD The disclosure relates generally to expansion joints. More specifically, the disclosure relates to an expansion joint for a gas turbine exhaust system. BACKGROUND Gas turbine (GT) systems, as used for electrical power generation, typically include a compressor section, a combustion section that generates hot combustion gases from fuel and air from the compressor section, a turbine section that expands the hot combustion gases to produce work, and an exhaust section that conveys the energy-depleted gases from the GT system. A diffuser duct is commonly positioned between the turbine section and the exhaust section. The diffuser duct provides performance benefits to the GT system as a whole by expanding the exhaust gases to achieve optimum aerodynamic pressure recovery. The diffuser duct may have two parts, such as a forward part that is externally insulated and an aft part that is internally insulated. An expansion joint may be used to join the forward and aft parts of the diffuser duct, as well as connecting the turbine duct flange and the diffuser duct flange. Most turbine ducts run hot and are machined structures, while most diffuser ducts are lower cost fabricated casings that are internally insulated and relatively cold. The thermal mismatch at this connection requires an expansion joint to accommodate the large relative displacements between these components. The expansion joints must be able to accommodate large axial, vertical, and lateral movements. One approach to providing an expansion joint uses a vertically mounted flexible element coupled between the turbine duct aft flange and the diffuser duct forward flange. A vertical offset between the flanges provides a location to attach each end of the flexible vertical element. This approach presents a number of challenges. For example, higher temperature exhaust is becoming more common with the increased use of hydrogen fuel. The flexible elements must be made of highly flexible material, such as superalloys made from nickel with chromium, iron, and other metals like cobalt, manganese, copper, niobium, and tantalum (e.g., INCONEL® materials), but they are unable to withstand higher temperature exhaust, e.g., higher than 650° C. (˜1200°F). Unfortunately, conventional flexible element expansion joints may not withstand the higher back-pressures of current downstream emissions reduction systems. The flexible elements also must be carefully coupled using complex mounting systems to prevent wear and to ensure proper operation, which increases the complexity of assembly and maintenance. The flexible elements also require a separate collection trough to capture water from turbine water washes that may enter expansion joint insulation and otherwise flow out onto the ground. BRIEF DESCRIPTION All aspects, examples and features mentioned below can be combined in any technically possible way. An aspect of the disclosure provides an expansion joint for use between a turbine duct flange and a diffuser duct flange of a gas turbine exhaust system, the expansion joint comprising: a plurality of arcuate expansion joint segments configured to be arranged circumferentially to collectively form an annular expansion joint assembly, the plurality of arcuate expansion joint segments each including: a rigid seal plate having an inner radial end and an outer radial end; a first pivot coupler pivotally coupling the inner radial end to the turbine duct flange; and a second pivot coupler pivotally coupling the outer radial end to the diffuser duct flange, wherein each of the first and second pivot couplers includes: a mount member fixedly coupled to a respective duct flange and pivotally engaging the rigid seal plate; a clamp member pivotally engaging the rigid seal plate; and at least one actuator configured to press a respective radial end of the rigid seal plate between the clamp member and the mount member. Another aspect of the disclosure includes any of the preceding aspects, and the at least one actuator includes: a post fixedly coupled at one end thereof to a respective duct flange and extending through a first opening in the mount member, a second opening in a respective radial end of the rigid seal plate, and a third opening in the clamp member; a force applicator operatively coupled to the post; and a holder coupled to the post and engaging the force applicator, wherein the force applicator forces the clamp member and the respective radial end of the rigid seal plate against the mount member. Another aspect of the disclosure includes any of the preceding aspects, and the second opening in the inner radial end of the rigid seal plate includes a through-hole extending through the rigid seal plate, and the second opening in the outer radial end of the rigid seal plate includes a slot extending through the rigid seal plate and open to a radial outer edge of the rigid seal plate. Another aspect of the disclosure includes any of the preceding aspects, and fur