Turbine bucket and wheel assembly with integral bucket shroud

A turbine wheel and bucket assembly comprising a wheel having a peripheral rim machined to include a dovetail shape about the circumference of said rim, interrupted, only by a bucket installation slot;

• and a plurality of buckets installed on said wheel, each bucket having a dovetail portion and blade portion, with the dovetail portion machined to include a complementary dovetail shape enabling each said bucket to be slidably received on said wheel dovetail shape;
• each bucket having an integral cover at a radial tip of said blade portion, each cover having axially extending surfaces on either side of angled contact surfaces adapted to engage mating contact surfaces of adjacent covers such that said buckets are pretwisted in a first direction and further including a keyway formed in said bucket dovetail portion and a key provided on said rim, said key receivable within said keyway to prevent rotation of said dovetail portion of the bucket relative to the wheel.

A turbine wheel and bucket assembly comprising a wheel having a peripheral rim machined to include a dovetail shape about the circumference of said rim, interrupted only by a bucket installation slot;

• and a plurality of buckets installed on said wheel, each bucket having a dovetail portion and blade portion, with the dovetail portion machined to include a complementary dovetail shape enabling each said bucket to be slidably received on said wheel dovetail shape;
• and further including a keyway formed in said dovetail portion and a key provided on said rim, said key receivable within said keyway to prevent rotation of said dovetail portion of the bucket relative to the wheel.

A turbine wheel and bucket assembly comprising a wheel having a peripheral rim machined to include a dovetail shape about the circumference of said rim, interrupted only by a bucket installation slot;

• and a plurality of buckets installed on said wheel, each bucket having a dovetail portion and blade portion, with the dovetail portion machined to include a complementary dovetail shape enabling each said bucket to be slidably received on said wheel dovetail shape;
• each bucket having an integral cover at a radial tip of said blade portion, said cover incorporating first means for introducing pretwist into each said blade portion of said plurality of buckets, and said wheel dovetail shape and said bucket dovetail shape incorporating second means for preventing rotation of said bucket dovetail portion.