US-12624643-B2 - Rotary machine seal having a wear protection assembly with an abradable covering

US12624643B2US 12624643 B2US12624643 B2US 12624643B2US-12624643-B2

Abstract

A seal assembly for rotary machines having a wear protection assembly with an abradable covering. The wear protection assembly has one or more wear protection features that enable in-operation opening of the seal assembly by increasing a clearance between a seal rotor and a seal slider of the seal assembly. In particular, the wear protection assembly is configured to open the seal assembly and increase the clearance of the seal rotor and the seal slider during slider air-bearing wear conditions, slider counterbore wear conditions, rotor air-bearing wear conditions, or extreme vibration wear conditions. Under such or similar wear conditions (or under conditions preceding or leading up to a wear condition), the wear protection assembly yields a pressure gradient and/or a fluid flow that oppose the forces acting to decrease the clearance between the seal rotor and the seal slider.

Inventors

Narendra Anand Hardikar
Scott Alan Schimmels

Assignees

GENERAL ELECTRIC COMPANY

Dates

Publication Date: 20260512
Application Date: 20241111

Claims (14)

1 . A rotary machine, comprising: a stator; a rotor configured to rotate with respect to the stator, the rotor being arranged with the stator at a rotor-stator interface; and a seal assembly at the rotor-stator interface, the seal assembly comprising: a seal cavity defined by a seal rotor and a seal slider of a seal stator, the seal rotor defining a rotor face, the seal slider defining a slider face and an air bearing wall, wherein the seal slider comprises a high-pressure aspiration conduit; at least one non-contacting seal interface; and a wear protection assembly comprising an abradable covering positioned over an opening of the high-pressure aspiration conduit; wherein, during operation of the rotary machine, and upon the seal rotor and the seal stator of the rotary machine making contact with each other at the rotor-stator interface such that the seal cavity of the seal assembly is at least partially closed, allowing a portion of the seal rotor to abrade the abradable covering to expose the opening, thereby allowing airflow to pressurize a trench cavity defined by the at least partially closed seal cavity and the slider face of the seal slider, wherein the pressurized trench cavity is configured to at least partially reopen the seal cavity, wherein the opening of the high-pressure aspiration conduit is defined by the slider face of the seal slider, and wherein the high-pressure aspiration conduit is integral with the seal slider, wherein the wear protection assembly further comprises an opening cover arranged between the opening of the high-pressure aspiration conduit and the abradable covering.
2 . The rotary machine of claim 1 , wherein the seal assembly is configured as at least one of an aspirating face seal, a fluid bearing, a gas bearing, or a film riding seal.
3 . The rotary machine of claim 1 , wherein the opening cover and the opening of the high-pressure aspiration conduit form an air pocket therebetween.
4 . The rotary machine of claim 1 , wherein the wear protection assembly further comprises a weld structure securing the opening cover on the slider face over the opening.
5 . The rotary machine of claim 1 , wherein the opening is at an outlet of a secondary airflow channel of the high-pressure aspiration conduit, the secondary airflow channel being in fluid communication with a primary airflow channel of the high-pressure aspiration conduit.
6 . The rotary machine of claim 1 , wherein the portion of the seal rotor is a primary tooth of the seal rotor.
7 . The rotary machine of claim 1 , wherein the abradable covering has a thickness less than a thickness of the air bearing wall of the seal slider.
8 . A rotary machine, comprising: a stator; a rotor configured to rotate with respect to the stator, the rotor being arranged with the stator at a rotor-stator interface; and a seal assembly at the rotor-stator interface, the seal assembly comprising: a seal cavity defined by a seal rotor and a seal slider of a seal stator, the seal rotor defining a rotor face, the seal slider defining a slider face and an air bearing wall, wherein the seal slider comprises a high-pressure aspiration conduit; at least one non-contacting seal interface; and a wear protection assembly comprising an abradable covering positioned over an opening of at least one hole extending partially through a thickness of the rotor face such that a seal-side of the at least one hole is covered during non-contacting conditions, wherein, during operation of the rotary machine, and upon the seal rotor and the seal stator making contact with each other at the rotor-stator interface such that the seal cavity is at least partially closed, allowing a portion of the seal slider to abrade the abradable covering to expose the opening, thereby allowing airflow to enter the at least one hole to pressurize a trench cavity defined by the at least partially closed seal cavity and the slider face of the seal cavity, wherein the pressurized trench cavity is configured to at least partially reopen the seal cavity, wherein the wear protection assembly further comprises an opening cover arranged between the opening of the at least one hole and the abradable covering.
9 . The rotary machine of claim 8 , wherein the seal assembly is configured as at least one of an aspirating face seal, a fluid bearing, a gas bearing, or a film riding seal.
10 . The rotary machine of claim 8 , wherein the opening cover and the opening of the at least one hole form an air pocket therebetween.
11 . The rotary machine of claim 8 , wherein the wear protection assembly further comprises a weld structure securing the opening cover on the slider face over the opening.
12 . The rotary machine of claim 8 , wherein the abradable covering has a thickness less than a thickness of the air bearing wall of the seal slider.
13 . A rotary machine, comprising: a stator; a rotor configured to rotate with respect to the stator; and a member coupled to or formed integrally with the stator or the rotor, the member defining a high-pressure aspiration conduit and comprising a wear surface, the member including an abradable covering positioned over an opening of the high-pressure aspiration conduit, the abradable covering configured to wear during an operation of the stator and the rotor to allow a high pressure airflow through the opening, wherein the member further comprises an opening cover arranged between the opening of the high-pressure aspiration conduit and the abradable covering.
14 . The rotary machine of claim 13 , wherein the abradable covering comprises successive layers of abradable material.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a divisional application of U.S. application Ser. No. 17/979,113 filed Nov. 2, 2022, which is hereby incorporated by reference in its entirety. FIELD The present disclosure generally relates to rotary machines, and more particularly, to seal assemblies for rotary machines. BACKGROUND Gas turbine engines, and other similar rotary machines, generally include a turbine section downstream of a combustion section that is rotatable with a compressor section to rotate and operate the gas turbine engine to generate power, such as propulsive thrust. Typically, the turbine section defines a high pressure turbine in serial flow arrangement with an intermediate pressure turbine and/or low pressure turbine. The high pressure turbine includes an inlet or nozzle guide vane between the combustion section and the high pressure turbine rotor. The nozzle guide vane generally serves to accelerate a flow of combustion gases exiting the combustion section to more closely match or exceed the high pressure turbine rotor speed along a tangential or circumferential direction. Thereafter, turbine sections generally include successive rows or stages of stationary and rotating airfoils, or vanes and blades, respectively. In addition, rotary machines including turbomachines or gas turbine engines have seals between rotating components (e.g., rotors) and corresponding stationary components (e.g., stators). These seals may help to reduce leakage of fluids between the rotors and stators. These seals may additionally or alternatively help separate fluids that have respectively different pressures and/or temperatures. The sealing properties of a seal may impact not only the amount of leakage and/or separation of fluids, but also the overall operation and/or operating efficiency of the rotary machine. An example seal in a gas turbine engine is a non-contacting film riding aspirating face seal of the rotor. However, during high vibration, stalls, and/or high thermal gradients (such as burst chop re-burst or high maneuvers), the AFS (aspirating face seal) air bearing can experience metal-to-metal contact between the rotor and the stator, thereby causing rubs and air bearing wear. This may change the seal force balance, thereby causing the seal to run tighter, which can lead to more rubs and wear. Moreover, metal-to-metal contact can generate high heat and temperature rise and potentially initiate cracks that may propagate through the rotor. BRIEF DESCRIPTION OF THE DRAWINGS A full and enabling disclosure, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended Figures, in which: FIG. 1 is a schematic cross-sectional view of a rotary machine that includes a gas turbine engine according to embodiments of the present disclosure; FIG. 2 is a cross-sectional view of a portion of a gas turbine engine that includes a seal or seal assembly according to embodiments of the present disclosure; FIG. 3 is an enlarged cross-sectional view of the seal in FIG. 2 in an opened engine off position according to an embodiment of the present disclosure; FIG. 4 is a cut-away perspective view of a stator portion of the seal in FIG. 3 according to an embodiment of the present disclosure; FIG. 5 is a cross-sectional view of the seal in FIG. 3 in a closed position according to an embodiment of the present disclosure; FIG. 6 is a diagram of forces acting on the seal in FIG. 5. according to an embodiments of the present disclosure; FIG. 7 is a diagram of air flows through the seal in FIG. 5 according to an embodiments of the present disclosure; FIG. 8 is a cross-sectional view of a slider and the seal in FIG. 5 according to an embodiments of the present disclosure; FIG. 9 is a cross-sectional view of a seal of the portion of the gas turbine engine in FIG. 2 in a closed engine on position according to an embodiments of the present disclosure; FIG. 10A is a schematic view of a seal assembly of the gas turbine engine in FIG. 2 in an open engine on position according to an embodiment of the present disclosure, particularly illustrating a clearance at the rotor-stator interface being open; FIG. 10B is a schematic view of another seal assembly of the gas turbine engine of FIG. 2 in an closed engine on position according to an embodiment of the present disclosure, particularly illustrating a clearance at the rotor-stator interface being closed such that contact occurs between a seal rotor and seal slider during operation; FIG. 11A is a detailed, schematic view of a portion of a seal assembly according to an embodiment of the present disclosure; FIG. 11B is a detailed view of the portion of the seal assembly illustrated in FIG. 11A, particularly illustrating features of a wear protection assembly according to an embodiment of the present disclosure; FIG. 12A shows a detailed, schematic view of a portion of another seal assembly