Secondary sealing system

Patent metadata

Field	Value
Publication number	US-2016169040-A1
Application number	US-201514856072-A
Country	US
Kind code	A1
Filing date	Sep 16, 2015
Priority date	Dec 16, 2014
Publication date	Jun 16, 2016
Grant date	—

Abstract

The present disclosure includes sealing systems comprising a secondary seal with one or more of a knife edge seal and a discourager. The secondary seal may act to isolate an interface between an inner and outer shaft and a bearing compartment. The inner and outer shafts may be high pressure compressor and low pressure turbine shafts, respectively.

First claim

What is claimed is:

1 . A sealing system comprising:
an intershaft seal separating a bearing compartment from an annulus; an outer shaft concentrically surrounding at least a portion of an inner shaft, wherein an interface between the outer shaft and the inner shaft is located within the annulus; and a secondary seal positioned within the annulus.

2 . The sealing system of claim 1 , wherein the secondary seal is configured to substantially prevent a lubricating oil in the annulus from entering the interface.

3 . The sealing system of claim 1 , wherein the secondary seal comprises at least one knife edge seal.

4 . The sealing system of claim 1 , wherein the secondary seal comprises a discourager.

5 . The sealing system of claim 1 , wherein the intershaft seal is configured to prevent a lubricating oil in the bearing compartment from entering the annulus.

6 . The sealing system of claim 1 , further comprising an oil drain located in the annulus.

7 . The sealing system of claim 1 , wherein the intershaft seal comprises a buffer air inlet.

8 . The sealing system of claim 1 , wherein the outer shaft comprises a high pressure compressor shaft.

9 . The sealing system of claim 1 , wherein the inner shaft comprises a low pressure turbine shaft.

10 . A gas turbine engine comprising:
an intershaft seal separating a bearing compartment from an annulus and configured to prevent a lubricating oil in the bearing compartment from entering the annulus; an outer shaft concentrically surrounding at least a portion of an inner shaft, wherein an interface between the outer shaft and the inner shaft is located within the annulus; and a secondary seal positioned within the annulus and configured to prevent the lubricating oil in the annulus from entering the interface.

11 . The gas turbine engine of claim 10 , wherein the secondary seal comprises at least one of a knife edge seal and a discourager.

12 . The gas turbine engine of claim 10 , further comprising an oil drain located in the annulus.

13 . The gas turbine engine of claim 10 , wherein the intershaft seal comprises a buffer air inlet.

14 . The gas turbine engine of claim 10 , wherein the outer shaft comprises a high pressure compressor shaft.

15 . The gas turbine engine of claim 10 , wherein the inner shaft comprises a low pressure turbine shaft.

16 . A gas turbine engine comprising:
an outer shaft concentrically surrounding at least a portion of an inner shaft, wherein an interface between the outer shaft and the inner shaft is located within an annulus; and a secondary seal positioned within the annulus and configured to prevent a lubricating oil in the annulus from entering the interface and comprising at least one knife edge seal.

17 . The gas turbine engine of claim 16 , wherein the secondary seal comprises at least one discourager.

18 . The gas turbine engine of claim 16 , further comprising an oil drain located in the annulus.

19 . The gas turbine engine of claim 16 , wherein the outer shaft comprises a high pressure compressor shaft and the inner shaft comprises a low pressure turbine shaft.

20 . The gas turbine engine of claim 16 , further comprising an intershaft seal separating the annulus from a bearing compartment and configured to prevent the lubricating oil in the bearing compartment from entering the annulus, wherein the intershaft seal comprises a buffer air inlet.

Assignees

• United Technologies Corp

Inventors

• Anglin Christopher
• Yuen Yuk-Kwan

Classifications

• F01D5/026

  Shaft to shaft connections · CPC title

• F05D2220/30

  in turbines · CPC title

• F05D2240/55

  Seals · CPC title

• F01D11/00

  Preventing or minimising internal leakage of working-fluid, e.g. between stages (sealings in general F16J {; sealing arrangements for transition ducts of combustor cans F01D9/023}) · CPC title

• F04D29/102

  especially adapted for elastic fluid pumps · CPC title