Gas turbine combustor barrier structures for spring clips

1. A combustor of a gas turbine engine, comprising an external surface and a plurality of spring clips disposed externally and circumferentially along a downstream portion of the external surface to contact an upstream end of a transition piece into which the combustor is engaged, further comprising a barrier structure positioned to form a containment space surrounding the spring clips and defined by the barrier structure, the transition piece, and the downstream portion, the barrier structure adapted to form a tortuous path adjacent an upstream opening from the containment space, whereby an entire spring clip, or a fragment thereof of a predetermined size, cannot exit the upstream opening through the tortuous path and is thereby retained in the containment space.

2. The combustor of claim 1 wherein the barrier structure additionally comprises an elevated contact surface adapted to make contact with a respective spring clip upon radially inward compression of the spring clip, to limit the radially inward compression of the spring clip.

3. The combustor of claim 2 , wherein the barrier structure comprises an annular shape, a cylindrical attachment region having an inside diameter sized to slidingly engage over the external surface, the elevated contact surface, and an outwardly oriented retention barrier disposed upstream of the elevated contact surface.

4. The combustor of claim 3 , wherein the radially outwardly oriented retention barrier has an elevation effective to restrict access to interior sides of the spring clips, whereby such access restriction prevents radially outward manipulation of the spring clips during combustor installation and removal.

5. The combustor of claim 1 , wherein the barrier structure is additionally adapted to restrict access to interior sides of the spring clips, whereby such access restriction prevents radially outward manipulation of the spring clips during combustor installation and removal.

6. The combustor of claim 5 , wherein the barrier structure comprises an annular shape and comprises a cylindrical attachment region having an inside diameter sized to slidingly engage over the external surface, an elevated contact surface adapted to restrict radially inward movement of a respective spring clip, and a substantially radially outwardly oriented retention barrier, disposed upstream of the elevated contact surface and providing said access restriction.

7. The combustor of claim 5 , wherein the access restriction is effective to restrict access by a human hand.

8. The combustor of claim 1 , wherein said tortuous path is effective to retain in the containment space a spring clip fragment comprising an entire spring clip except for an attachment area at which a weld connects the entire spring clip to the external surface.

9. The combustor of claim 1 , wherein said tortuous path is effective to retain in the containment space a predetermined size spring clip fragment having a length at least about 50 percent of the length of an entire spring clip from which the fragment was formed.

10. The combustor of claim 1 , wherein said tortuous path is effective to retain in the containment space a predetermined size spring clip fragment having a length at least about 75 percent of the length of an entire spring clip from which the fragment was formed.

11. A combustor of a gas turbine engine having an external surface, comprising a plurality of spring clips disposed externally and circumferentially along a downstream portion of the external surface to contact an upstream end of a transition piece into which the combustor is engaged, and a barrier structure positioned in relation to the spring clips and the transition piece to form a containment space defined by the barrier structure, the transition piece, and the portion, the barrier structure comprising a generally circular shape and comprising a cylindrical attachment region having an inside diameter sized to slidingly engage over the external surface, an annular elevated contact surface adapted to restrict radially inward movement of a respective spring clip, and a substantially radially outwardly oriented retention barrier, disposed upstream of the elevated contact surface and effective to restrict access to interior sides of the spring clips, the barrier structure adapted to create a tortuous path adjacent an opening from the containment space, whereby a spring clip fragment cannot pass through the tortuous path to the opening and is thereby retained in the containment space.

12. A gas turbine engine comprising a compressor, a combustor comprising an external surface and an inlet and an outlet, the combustor outlet adapted to engage an inlet of a transition, and a gas turbine in fluid communication with an outlet of the transition, the combustor outlet and the transition inlet overlappingly disposed to define an annular space therebetween, a spring clip disposed in the annular space, and a barrier structure restricting an exit end of the annular space whereby an entire spring clip, or a fragment thereof of a predetermined size, cannot pass from the annular space, wherein the barrier structure is ring-shaped and comprises a cylindrical attachment region having an inside diameter sized to slidingly engage over the external surface, an annular elevated contact surface adapted to restrict radially inward movement of a respective spring clip, and a substantially radially outwardly oriented retention barrier, disposed upstream of the elevated contact surface, effective to restrict access by a human hand to interior sides of the respective spring clips.

13. The combustor of claim 12 , wherein the barrier structure is additionally adapted to restrict access to interior sides of the respective spring clips, whereby such access restriction prevents radially outward manipulation of the spring clips during combustor installation and removal.

14. The combustor of claim 12 , wherein said tortuous path is effective to retain in the containment space a predetermined size spring clip fragment having a length at least about 50 percent of the length of an entire spring clip from which the fragment was formed.

15. The combustor of claim 12 , wherein said tortuous path is effective to retain in the containment space a predetermined size spring clip fragment having a length at least about 75 percent of the length of an entire spring clip from which the fragment was formed.

16. A gas turbine engine comprising a compressor, a combustor comprising an external surface and an inlet and an outlet, the combustor outlet adapted to engage an inlet of a transition, and a gas turbine in fluid communication with an outlet of the transition, the combustor outlet and the transition inlet overlappingly disposed to define an annular space therebetween, a spring clip disposed in the annular space, and a barrier structure restricting an exit end of the annular space whereby an entire spring clip, or a fragment thereof of a predetermined size, cannot pass from the annular space, wherein the barrier structure additionally comprises an elevated contact surface adapted to make contact with a respective spring clip upon radially inward compression of the spring clip, to limit the radially inward compression of the spring clip, and wherein the barrier structure comprises an annular shape, a cylindrical attachment region having an inside diameter sized to slidingly engage over the external surface, the elevated contact surface, and an outwardly oriented retention barrier disposed upstream of the elevated contact surface.

17. The combustor of claim 16 wherein the radially outwardly oriented retention barrier has an elevation effective to restrict access to the interior sides of the spring clips, whereby such access restriction prevents radially outward manipulation of the spring clips during combustor installation and removal.