Bucket and wheel dovetail design for turbine rotors

A dovetail joint between a rotor wheel and a bucket, the joint comprising a male dovetail component on the rotor wheel and a female dovetail component in the bucket, wherein the male dovetail component includes four laterally projecting hooks, each hook from an uppermost hook to a lowermost hook decreasing in radial thickness and increasing in axial strength;

• wherein each hook has a substantially flat top surface;
• and further wherein a neck joins a lower surface of one hook to the top surface of an underlying hook, said neck including an upper fillet having a plurality of radii and a lower fillet having a single radius.

A dovetail joint for attaching a turbine bucket to a rotor wheel, comprising a male wheel dovetail component and a substantially complementary female bucket dovetail component wherein the male dovetail component receives the female dovetail component in a direction tangential to the rotor wheel;

• and further wherein said wheel dovetail component includes a plurality of laterally extending hooks which decrease in radial thickness from an uppermost hook to a lowermost hook, and wherein each hook is formed with a substantially flat top surface.

A dovetail joint for attaching a turbine bucket to a rotor wheel comprising a male wheel dovetail component and a substantially complementary female bucket dovetail component;

• said wheel dovetail component including a plurality of laterally extending hooks which decrease in radial thickness from an uppermost hook to a lowermost hook, wherein each hook is formed with a substantially flat top surface and further wherein a neck joins a lower surface of one hook to the top surface of an underlying hook, said neck including an upper fillet having a plurality of radii and a lower fillet having a single radius.

A dovetail joint for attaching a turbine bucket to a rotor wheel, wherein the dovetail joint comprises a male wheel dovetail and a substantially complementary female bucket dovetail;

• and further wherein said wheel dovetail includes a plurality of laterally extending hooks;
• and wherein a neck joins a lower surface of one hook to the top surface of an underlying hook, said neck including an upper fillet having a plurality of radii and a lower fillet having a single radius.