Method for repairing a blade
A method for repairing a blade in a gas turbine engine comprises the steps of: isolating the damage on the airfoil of the blade; forming a cut back in the shape of elongated “D” shaped recess with a pair of fillets, a depth and a longitudinal axis of the “D” shaped recess having a length along the leading or trailing edge of the airfoil; and the fillets having a respective radius.
1. A method for repairing a blade in a gas turbine engine comprising:
identifying a damage in one of a leading edge and a trailing edge of an airfoil of the blade;
forming a cutback around the damage in the one of the leading edge and trailing edge, the cutback shaped to comprise at least a pair of fillets r 1 and r 2 in the one of the leading edge and trailing edge on opposite ends of the cutback, a depth d from the one of the leading edge and trailing edge, and a length l along the one of the leading edge and the trailing edge, a radius of each of the fillets r 1 and r 2 being shorter than the length l.
2. The method according to claim 1 , wherein forming the cutback comprises forming the fillets r 1 and r 2 each with a different radius.
3. The method according to claim 1 , wherein forming the cutback comprises spacing the fillets r 1 and r 2 apart relative to one another in the cutback.
4. The method according to claim 3 , wherein spacing the fillets r 1 and r 2 apart relative to one another in the cutback comprises spacing the fillets r 1 and r 2 apart with one of a generally straight edge portion and an edge portion having a radius of curvature larger than r 1 and r 2 .
5. The method according to claim 1 , wherein forming the cutback comprises forming the cutback with l/d being from 1 to 20.
6. The method according to claim 1 , wherein forming the cutback comprises forming the cutback with l being between 0.060″ and 3.00″; and d being between 0.030″ and 1.5″.
7. The method according to claim 1 , wherein forming the cutback comprises forming the cutback to have a generally constant depth from the fillet r 1 to the fillet r 2 .
8. A blade in a gas turbine engine comprising:
an airfoil having a leading edge and a trailing edge; and
a cutback machined one edge among the leading and trailing edges at a location of damage, the cutback comprising a shape defined by at least a pair of fillets r 1 and r 2 in the one of the leading edge and trailing edge on opposite ends of the cutback, a depth d from the one of the leading edge and trailing edge, and a length l along the one of the leading edge and trailing edge, a radius of each of the fillets r 1 and r 2 being shorter than the length l.
9. The blade according to claim 8 , wherein the fillets r 1 and r 2 each have a same radius.
10. The blade according to claim 8 , wherein the fillets r 1 and r 2 are spaced apart by an edge portion in the cutback.
11. The blade according to claim 10 , wherein the edge portion spacing the fillets r 1 and r 2 apart relative to one another in the cutback is one of a generally straight edge portion and an edge portion having a radius of curvature larger than r 1 and r 2 .
12. The blade according to claim 8 , wherein the cutback is defined by l/d being from 1 to 20.
13. The blade according to claim 8 , wherein the cutback is defined by l being between 0.060″ and 3.00″; and d being between 0.030″ and 1.5″.
14. The blade according to claim 8 , wherein the cutback has a generally constant depth from the fillet r 1 to the fillet r 2 .
15. A gas turbine engine comprising:
at least one blade having a leading edge and a trailing edge; and
a cutback machined in one of a leading edge and a trailing edge at a location of damage, the cutback comprising a shape defined by at least a pair of fillets r 1 and r 2 in the one of the leading edge and trailing edge on opposite ends of the cutback, a depth d from the one of the leading edge and trailing edge, and a length l along the one of the leading edge and trailing edge, a radius of each of the fillets r 1 and r 2 being shorter than the length l.
16. The gas turbine engine according to claim 15 , wherein the fillets r 1 and r 2 each have a same radius.
17. The gas turbine engine according to claim 15 , wherein the fillets r 1 and r 2 are spaced apart by an edge portion in the cutback.
18. The gas turbine engine according to claim 17 , wherein the edge portion spacing the fillets r 1 and r 2 apart relative to one another in the cutback is one of a generally straight edge portion and an edge portion having a radius of curvature larger than r 1 and r 2 .
19. The gas turbine engine according to claim 17 , wherein the edge portion is parallel to a portion of the leading edge in which the cutback is formed.
20. The gas turbine engine according to claim 15 , wherein the cutback is defined by l/d being from 1 to 20.
21. The gas turbine engine according to claim 15 , wherein the cutback is defined by l being between 0.060″ and 3.00″; and d being between 0.030″ and 1.5″.
22. The gas turbine engine according to claim 15 , wherein the cutback has a generally constant depth from the fillet r 1 to the fillet r 2 .