Seal with backup seal

Patent metadata

Field	Value
Publication number	US-10161256-B2
Application number	US-201514603033-A
Country	US
Kind code	B2
Filing date	Jan 22, 2015
Priority date	Jan 22, 2015
Publication date	Dec 25, 2018
Grant date	Dec 25, 2018

Abstract

A sealing arrangement has a turbine static structure with contact surfaces, a bearing compartment with contact surfaces, and a cavity between the turbine static structure and the bearing compartment. There are also two seals, wherein each seal is configured to contact the turbine static structure and the bearing compartment.

First claim

The invention claimed is:

1. A sealing arrangement comprising:
a turbine static structure having a first contact surface and a second contact surface distal from the first contact surface;
a bearing compartment that is surrounded by the turbine static structure having a third contact surface and a fourth contact surface that is distal from the third contact surface;
a cavity between the turbine static structure and the bearing compartment;
a piston seal positioned between the turbine static structure and the bearing compartment that inhibits forward flow from the cavity into a fastener compartment, the piston seal being configured to contact the first contact surface and the third contact surface, wherein the third contact surface is a cylindrical surface having a constant radius about a centerline axis of the bearing compartment, and wherein the piston seal has a joint permitting diametric expansion of the piston seal; and
a w-seal seal positioned between the turbine static structure and the bearing compartment that inhibits forward flow from the bearing compartment into a rotor compartment, the w-seal seal being configured to contact the second contact surface and the fourth contact surface, wherein the first contact surface, the second contact surface, and the fourth contact surface are axially-facing annular surfaces.

2. The sealing arrangement of claim 1 , wherein the w-seal is configured to be expanded by reverse flow from the rotor compartment into the fastener compartment.

3. The sealing arrangement of claim 2 , wherein the piston seal and the turbine static structure further comprises:
a fifth contact surface opposing the first contact surface that the piston seal is configured to contact to inhibit reverse flow from the fastener compartment into the cavity.

4. The sealing arrangement of claim 3 , wherein the turbine static structure further comprises:
an inner case; and
a seal ring fastened to the inner case;
wherein the first contact surface, the second contact surface, and the fifth contact surface are on the seal ring.

5. The sealing arrangement of claim 1 , wherein the w-seal seal is directly radially inward of the piston seal.

6. The sealing arrangement of claim 1 , wherein the turbine static structure further comprises:
an inner case; and
a seal ring fastened to the inner case;
wherein the first contact surface and the second contact surface are on the seal ring.

7. The sealing arrangement of claim 6 , wherein a piston seal is positioned in a groove in the seal ring that substantially surrounds a first side, a second side, and a third side of the piston seal.

8. The sealing arrangement of claim 1 , wherein the bearing compartment further comprises:
a heat shield;
wherein the third contact surface and the fourth contact surface are on the heat shield.

9. A gas turbine engine arranged along an axis, the gas turbine engine comprising:
a fan;
a first compressor downstream of the fan;
a second compressor downstream of the first compressor;
a combustor downstream of the second compressor;
a first turbine downstream of the combustor;
a second turbine downstream of the first turbine;
a turbine static structure proximate at least one of the first turbine and the second turbine;
a bearing compartment connected to the turbine static structure;
a cavity between the turbine static structure and the bearing compartment;
a flowpath extending from the cavity to one of the first turbine and the second turbine, the flowpath being bordered by the turbine static structure and the bearing compartment;
a first seal positioned between the turbine static structure and the bearing compartment, the first seal being configured to contact the turbine static structure and the bearing compartment during operation of the gas turbine engine that inhibits flow in the flowpath; and
a second seal positioned between the turbine static structure and the bearing compartment, the second seal being configured to contact the turbine static structure and the bearing compartment during operation of the gas turbine engine that inhibits flow in the flowpath;
wherein the first seal is a piston seal and the second seal is a w-seal, and wherein, during operation of the gas turbine engine:
the first seal contacts a first axially-facing annular portion of the turbine static structure and a cylindrical portion of the bearing compartment during operation of the gas turbine engine, the cylindrical portion having a constant radius about a centerline axis of the bearing compartment; and
the second seal contacts a second axially-facing annular portion of the turbine static structure and a third axially-facing annular portion of the bearing compartment.

10. The gas turbine engine of claim 9 , wherein the first seal and the second seal are positioned at an axial position, with the first seal positioned at a first radial position from the axis and the second seal positioned at a second radial position that is nearer the axis than the first radial position.

11. The gas turbine engine of claim 9 , wherein the second seal is configured to expand with flow through the flowpath from one of the first and second turbines into the cavity.

12. The gas turbine engine of claim 9 , wherein the turbine static structure is positioned downstream of the first turbine and upstream of the second turbine.

13. The gas turbine engine of claim 9 , wherein the turbine static structure further comprises:
a gas tube;
a fairing surrounding the gas tube;
an inner case connected to the gas tube; and
a seal ring fastened to the inner case.

14. The gas turbine engine of claim 9 , wherein the turbine static structure further comprises:
a fastener compartment defined by the first seal, the second seal, the turbine static structure, and the bearing compartment; and
a fourth annular portion opposing the first annular portion that the piston seal is configured to contact to inhibit reverse flow from the fastener compartment into the cavity.

15. The gas turbine engine of claim 9 , wherein the first seal has a joint permitting diametric expansion of the first seal, and wherein an unexpanded inner diameter of the first seal is smaller than an outer diameter of the cylindrical portion.

Assignees

• United Technologies Corp
• Untied Tech Corporation

Inventors

• Porter Steven D
• Max Seth A

Classifications

• F01D25/16

  Arrangement of bearings; Supporting or mounting bearings in casings (bearings per se F16C) · CPC title

• F01D11/003 Primary

  by packing rings; Mechanical seals · CPC title

• F01D11/005 Primary

  Sealing means between non relatively rotating elements · CPC title

• F02C7/08 Primary

  Heating air supply before combustion, e.g. by exhaust gases · CPC title

• F01D25/12

  Cooling · CPC title