System and method for sealing internal channels defined in a component
A system for sealing an internal passage of a component includes a closure element positioned within the internal passage, and a joint material coupling the closure element to at least one passage wall that defines the internal passage. The system also includes a flexible braze element positioned proximate the closure element, the joint material, and the at least one passage wall.
1. A system for sealing an internal passage of a component, said system comprising:
a closure element positioned within the internal passage;
a joint material coupling said closure element to at least one passage wall that defines the internal passage;
a flexible braze element positioned proximate said closure element, said joint material, and the at least one passage wall; and
a braze paste adjacent said flexible braze element within the internal passage.
2. The system of claim 1 , wherein said flexible braze element comprises a solid material that is flexible at ambient temperatures.
3. The system of claim 1 , wherein said flexible braze element comprises a flexible tape.
4. The system of claim 3 , wherein said flexible tape comprises a mixture of a powdered low-melt braze material, a powdered high-melt material, and a binder.
5. The system of claim 3 , wherein said flexible tape comprises a mixture of a low-melt nickel brazing alloy and a high-melt nickel brazing alloy in a ratio within a range of from about 70:30 to about 30:70.
6. The system of claim 1 , wherein said braze paste and said flexible braze element are disposed sequentially in layers proximate said closure element.
7. The system of claim 6 , wherein said layers comprise a first paste layer disposed on said closure element, said flexible braze element as a first flexible braze element disposed on said first paste layer, and a second paste layer disposed on said first flexible braze element.
8. The system of claim 1 , wherein said braze paste comprises a low-melt nickel brazing alloy.
9. The system of claim 1 , wherein said closure element is sized and shaped to be received against the at least one passage wall in an interference fit proximate a closure site of the internal passage.
10. A method of sealing an internal passage of a component, said method comprising:
coupling a closure element to at least one passage wall that defines the internal passage using a joint material;
positioning a flexible braze element proximate the closure element, the joint material, and the at least one passage wall;
positioning a braze paste adjacent the flexible braze element within the internal passage; and
subjecting the component to at least one thermal cycle, such that a braze material of the flexible braze element forms a metallurgical bond with at least one of the closure element, the joint material, and the at least one passage wall.
11. The method of claim 10 , wherein positioning the flexible braze element comprises molding the flexible braze element into a space defined between the closure element and the at least one passage wall adjacent the joint material.
12. The method of claim 11 , wherein molding the flexible braze element comprises at least one of pushing the at least one flexible braze element into the space using a tool, and applying vacuum pressure to position the flexible braze element within the space.
13. The method of claim 10 , further comprising applying the braze paste and the flexible braze element sequentially in layers proximate the closure element.
14. The method of claim 13 , wherein applying the braze paste and the flexible braze element sequentially in layers comprises applying a first paste layer on the closure element, applying the flexible braze element as a first flexible braze element on the first paste layer, and applying a second paste layer on the first flexible braze element.
15. The method of claim 10 , further comprising applying the braze paste and the flexible braze element at least partially simultaneously.
16. The method of claim 10 , further comprising inserting the closure element through a first side of the internal passage, such that the closure element is received in an interference fit proximate a closure site within the internal passage.
17. The method of claim 10 , wherein positioning the flexible braze element comprises positioning a flexible tape.
18. The method of claim 17 , wherein positioning the flexible tape comprises positioning the flexible tape formed from a mixture of a powdered low-melt braze material, a powdered high-melt material, and a binder.