Internally cooled seal runner

Patent metadata

Field	Value
Publication number	US-9631508-B2
Application number	US-201313917075-A
Country	US
Kind code	B2
Filing date	Jun 13, 2013
Priority date	Jun 13, 2013
Publication date	Apr 25, 2017
Grant date	Apr 25, 2017

Abstract

A contact seal assembly for a shaft of a gas turbine engine includes a seal runner adapted to be connected to the shaft and rotatable relative to a carbon ring. The seal runner includes concentric inner and outer annular portions radially spaced apart to define at least one internal fluid passage between the inner and outer annular portions of the seal runner.

First claim

The invention claimed is:

1. A contact seal assembly for a shaft of a gas turbine engine, comprising:
one or more carbon ring segments mounted in a fixed position within a housing; and
an annular seal runner adapted to be connected to the shaft of the gas turbine engine and rotatable relative to the carbon ring segments, the seal runner being disposed adjacent to and radially inwardly from the carbon ring segments and abutting thereagainst during rotation of the seal runner to form a contact interface between the seal runner and the carbon ring segments which forms a substantially fluid tight seal;
the seal runner comprising concentric inner and outer annular portions which are radially spaced apart to define therebetween at least one internal fluid passage, said fluid passage formed by a plurality of serially interconnected passage segments which intersect each other to create a tortuous fluid flow path through the fluid passage, the plurality of serially interconnected passage segments defining the tortuous fluid flow path being adapted to receiving cooling fluid therein for cooling the seal runner from within, and the seal runner having multiple oil scoops integrally formed in the inner annular portion and disposed in fluid flow communication with the internal fluid passage, the multiple oil scoops being circumferentially spaced apart about the inner annular portion and feeding cooling oil into said fluid passage.

2. The contact seal assembly as defined in claim 1 , wherein the inner and outer annular portions of the seal runner are separately formed and engaged together.

3. The contact seal assembly as defined in claim 2 , wherein the outer annular portion defines a sleeve which fits over the inner annular portion and axially overlaps only a portion of the axially longer inner annular portion.

4. The contact seal assembly as defined in claim 3 , wherein the internal fluid passage extends axially between the inner and outer annular portions of the seal runner along at least a major portion of the axially overlapping length between the inner and outer annular portions.

5. The contact seal assembly as defined in claim 2 , wherein said fluid passage is formed by at least one radially-open channel provided in at least one of the first and second annular portions.

6. The contact seal assembly as defined in claim 2 , wherein the inner and outer annular portions of the seal runner are welded together at axial outer ends of the outer annular portion.

7. The contact seal assembly as defined in claim 1 , wherein the oil scoops each comprises at least one opening which radially extends through the inner annular portion of the seal runner.

8. The contact seal assembly as defined in claim 1 , wherein the multiple oil scoops each comprise a pair of openings radially extending through the inner annular portion and angled radially inwardly in a direction of rotation, to collect and force oil radially inwardly into an annular distribution channel formed in a radially inner surface of the inner annular portion of the seal runner.

9. The contact seal assembly as defined in claim 1 , wherein the internal fluid passage axially extends in a direction which is substantially parallel to and concentric with an axis of rotation of the seal runner.

10. The contact seal assembly as defined in claim 1 , wherein the fluid passage defines a serpentine shape.

11. The contact seal assembly as defined in claim 1 , wherein entry holes permit fluid inlet flow from the oil scoops to the fluid passage and exit holes permit fluid outlet flow from the fluid passage to outside the seal runner, wherein the entry holes provide greater fluid flow therethrough than the exit holes.

12. The contact seal assembly as defined in claim 11 , wherein the number of entry holes is greater than the number of exit holes.

13. The contact seal assembly as defined in claim 12 , wherein the number of the entry holes is more than six times the number of the exit holes.

14. The contact seal assembly as defined in claim 11 , wherein a diameter of the entry holes is greater than that of the exit holes.

15. The contact seal assembly as defined in claim 14 , wherein the diameter of the exit holes is less than ¾ of the diameter of the entry holes.

16. A gas turbine engine comprising one or more compressors, a combustor and one or more turbines, at least one of said compressors and at least one of said turbines being interconnected by an engine shaft rotating about a longitudinal axis thereof, at least one contact shaft seal being disposed about the rotating engine shaft to provide a fluid seal therewith, the contact shaft seal comprising one or more carbon ring assemblies having carbon ring segments mounted in a fixed position within a housing and an annular seal runner fixed to the engine shaft for rotation within the carbon ring assemblies, the seal runner abutting the carbon ring segments during rotation of the seal runner to form a contact interface therebetween which forms a substantially fluid tight shaft seal, the seal runner having concentric inner and outer annular portions which are radially spaced apart to define therebetween at least one internal fluid passage enclosed within the seal runner, the internal fluid passage formed by a plurality of serially interconnected passage segments which intersect each other to create a tortuous fluid flow path through the internal fluid passage and receiving cooling fluid therein for cooling the seal runner from within, the seal runner having multiple oil scoops integrally formed in the inner annular portion and disposed in fluid flow communication with the internal fluid passage, the multiple oil scoops being circumferentially spaced apart about the inner annular portion to feed cooling oil into said fluid passage.

17. A method of cooling an annular seal runner of a shaft seal assembly having carbon ring segments abutting the seal runner during relative rotation therebetween to form a contact interface between an outer runner surface of the seal runner and an inner surface of the carbon ring segments to form a fluid seal around the shaft, the method comprising:
providing the seal runner with an internal fluid passage disposed radially between inner and outer annular portions of the seal runner, the internal fluid passage formed by a plurality of serially interconnected passage segments which intersect each other to create a tortuous fluid flow path through the fluid passage;
using multiple oil scoops integrally formed in the inner annular portion of the seal runner to feed cooling oil into the internal fluid passage within the seal runner, the multiple oil scoops being circumferentially spaced apart about the inner annular portion; and
internally cooling at least a radially outer portion of the seal runner having the outer runner surface thereon by circulating the cooling oil through the internal fluid passage of the seal runner to cool the seal runner from within, including rotating the seal runner to collect the cooling oil using the multiple oil scoops and force the flow of the cooling oil through the internal fluid passage.

Assignees

• Pratt & Whitney Canada

Inventors

• Blais Daniel
• Lewis Alain
• Martel Alain C

Classifications

• F01D11/02 Primary

  by non-contact sealings, e.g. of labyrinth type (for sealing space between rotor blade tips and stator F01D11/08) · CPC title

• F01D25/12

  Cooling · CPC title

• F05D2260/232

  characterized by the cooling medium · CPC title

• F01D11/003 Primary

  by packing rings; Mechanical 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