Axial retention of a platform seal

Patent metadata

Field	Value
Publication number	US-9840931-B2
Application number	US-201314040813-A
Country	US
Kind code	B2
Filing date	Sep 30, 2013
Priority date	Nov 25, 2008
Publication date	Dec 12, 2017
Grant date	Dec 12, 2017

Abstract

A gas turbine engine component has an axial seal pin assembly for sealing between adjacent platform regions where the seal pin assembly design provides a seal pin damper slot extending to a forward axial stop in a forward buttress region. The forward axial stop includes a relief slot to interrupt the loadpath from the airfoil into the blade neck and attachment regions to reduce the stress concentrations in these regions.

First claim

Having thus described the invention, what is claimed is:

1. An axial pin seal assembly for a gas turbine blade comprising:
a substantially axially extending seal pin damper slot extending a distance between a pin damper slot forward wall buttress and an opposing pin damper slot aft wall buttress and having a forward end and opposing aft end;
a substantially radially extending forward axial stop located proximate the forward end of the seal pin damper slot, wherein the forward axial stop has a width extending between a forward-most axial stop wall and a forward axial stop wall on the opposite side of the width of the forward axial stop that opposes the pin damper slot forward wall;
a substantially radially extending aft axial stop located proximate the aft end of the seal pin damper slot;
a generally cylindrical seal pin positioned within the seal pin damper slot; and
a relief slot in the forward axial stop, the relief slot extending from the forward-most axial stop wall to the forward axial stop wall on the opposite side of the width of the forward axial stop that opposes the pin damper slot forward wall;
wherein the forward and aft axial stops limit axial movement of the seal pin.

2. The axial pin seal assembly of claim 1 , wherein the relief slot is located at a radially outer portion of the forward axial stop, adjacent a platform of the gas turbine blade.

3. The axial pin seal assembly of claim 1 , wherein the relief slot is located proximate a midspan of the forward axial stop and spans the width of the forward axial stop.

4. The axial pin seal assembly of claim 1 , wherein the seal pin damper slot is machined into the buttresses and a platform of the gas turbine blade.

5. The axial pin seal assembly of claim 1 , wherein the forward axial stop at least partially blocks the seal pin damper slot in order to prevent forward movement of the seal pin.

6. The axial pin seal assembly of claim 1 , wherein the relief slot cut extends into the forward axial stop a circumferential depth and an axial length.

7. The axial pin seal assembly of claim 6 , wherein the relief slot alters a loadpath on the blade such that mechanical load applied to the airfoil is not transmitted to a root of the blade by way of the forward axial stop.

8. A gas turbine blade assembly comprising:
an axially extending attachment;
a neck extending radially outward from the attachment and having a forward buttress and an opposing aft buttress;
a platform extending radially outward from the neck;
a seal pin damper slot extending along a sideface of the platform generally between a damper pin slot forward wall the forward buttress and an opposing pin damper slot aft wall buttress;
a generally radially extending forward axial stop, wherein the forward axial stop has a width extending between a forward-most axial stop wall and a forward axial stop wall on the opposite side of the width of the forward axial stop that opposes the pin damper slot forward wall extending through the forward buttress and to the platform and aft axial stop extending through the aft buttress and to the platform;
a generally cylindrical seal pin located within the seal pin damper slot;
a relief slot positioned in the forward axial stop and extending from the forward-most axial stop wall to the forward axial stop wall on the opposite side of the width of the forward axial stop that opposes the pin damper slot forward wall; and,
an airfoil extending radially outward from the platform.

9. The gas turbine blade assembly of claim 8 , wherein the relief slot is positioned proximate a midspan location of the forward axial stop.

10. The gas turbine blade assembly of claim 8 , wherein the relief slot is positioned at a radially outward portion of the forward axial stop, proximate the platform.

11. The gas turbine blade assembly of claim 8 , wherein the relief slot separates a loadpath between the airfoil and the forward buttress.

12. The gas turbine blade assembly of claim 8 , wherein the seal pin damper slot extends along a majority of an axial length of the platform.

13. The gas turbine blade assembly of claim 12 , wherein the seal pin generally blocks gases from entering or exiting the seal pin damper slot.

14. The gas turbine blade assembly of claim 8 , wherein the generally cylindrical seal pin is also retained by an adjacent turbine blade.

15. The gas turbine assembly of claim 8 , wherein the seal pin can move axially between the forward axial stop and the aft axial stop.

16. A method of sealing platform gaps between adjacent turbine blades in a gas turbine engine, comprising:
removing a portion of a forward buttress, a portion of an aft buttress and a portion of a platform in a turbine blade to form an axially extending seal pin slot having a seal pin slot forward wall, a seal pin slot aft wall, a forward axial stop, and an opposing aft axial stop, wherein the forward axial stop has a width extending between a forward-most axial stop wall and a forward axial stop wall on the opposite side of the width of the forward axial stop that opposes the pin damper slot forward wall;
forming a relief slot in the turbine blade by removing a portion of material adjacent to or in extending from the forward-most axial stop wall to the forward axial stop wall on the opposite side of the width of the forward axial stop that opposes the pin damper slot forward wall; and,
placing a generally cylindrical seal pin within the seal pin damper slot.

17. The method of claim 16 , wherein the seal pin damper slot and relief slot are machined into a cast turbine blade.

18. The method of claim 16 , wherein the portion of the material removed to form the relief slot is along a pressure side of the blade.

19. The method of claim 16 , wherein the relief slot breaks a loadpath between an airfoil of the turbine blade and a root portion of the blade.

20. The method of claim 16 , wherein the seal pin can move axially within the seal pin damper slot.

Assignees

• Ansaldo Energia Ip Uk Ltd

Inventors

• Joshi Gaurav K
• Hunt John Cuyler
• Maurell Orestes J
• Hart Adam L

Classifications

• F01D11/006 Primary

  Sealing the gap between rotor blades or blades and rotor · CPC title

• F01D5/3007

  of axial insertion type · CPC title

• F16J15/061

  with positioning means (F16J15/0831 takes precedence) · CPC title

• F01D5/22

  Blade-to-blade connections, {e.g. for damping vibrations} · CPC title

• F16J15/0887

  the sealing effect being obtained by elastic deformation of the packing · CPC title