Patent ID: 6957949

Claim:
In a gas turbine bucket having a shank portion and an airfoil portion having leading and trailing edges and pressure and suction sides, an internal cooling circuit, the internal cooling circuit having a serpentine configuration including plural radial outflow passages and plural radial inflow passages, and wherein a cooling inlet passage communicates with a first of said radial outflow passages along said trailing edge, said first of said radial outflow passages having a plurality of radially extending and radially spaced elongated rib segments extending between and connecting said pressure and suction sides in a middle region of said first radial outflow passage to prevent ballooning of said pressure and suction sides at said first radial outflow passage; said first of said radial outflow passages further including a turning vane in a radially outermost tip portion of said first radial outflow passage upstream of, but not extending into, a first of said radial inflow passages to thereby split coolant flow in the radially outer tip portion and to direct coolant flow in a top corner region of said trailing edge; prior to flow into said first of said radial inflow passages, said turning vane extending between and connected to said pressure and suction sides.