FIRST STAGE BUCKET

PART CHARACTERISTICS
Ansaldo Thomassen P/N:
76BXT150-G002

Interchangeable with GE P/N:
314B7162G015

Kit includes:
91x standard buckets
1x locking bucket
Installation hardware

Base alloy:
Alloy-111 DS

Coating:
Overaluminized CoNiCrAIY coating plus internal aluminide diffusion coating

Cooling configuration:
16 cooling holes

Firing temperatures:
Up to 1140°C (2084°F)

Inspection intervals:
24.000 EOH

COMPONENT HIGHLIGHTS
Operating conditions
Due to the specific design the Ansaldo Thomassen 6B first stage buckets are suitable for:

• Firing temperatures up to 1140°C (2084°F)
• Rotor speeds of 5163 rpm (PG6581)
• All gas turbine fuels

Design
The buckets are fabricated with the investment casting process and are made of a nickel base superalloy. The directionally solidified (DS) material structure results in an increased creep rupture strength.

The cooling system of the first stage buckets is designed for increased inlet temperatures. At the root, the cooling air enters the cooling channels via a cavity in the shank. The buckets are designed with 16 STEM drilled cooling holes around the airfoil perimeter. Turbulated cooling holes enhance the cooling capabilities even further and make this part suitable for turbine upgrades to higher firing temperatures.

To protect the part against corrosion and oxidation the first stage bucket is delivered with a LPPS sprayed MCrAlY coating on the gas path. The LPPS coating is overaluminized in order to make the bucket even more oxidation resistant at high temperatures.
To protect the base alloy around the cooling holes, the bucket is internally coated with an aluminide diffusion coating, applied by a chemical vapor deposition coating process. An aluminium seal coating is applied on the root serrations to minimize air leakage.
Ansaldo Thomassen can advice on coating solutions for specific operating conditions.

The delivery includes 91 standard buckets and 1 locking bucket. The complete set of parts is balanced and sequenced for assembly. The results of the moment weight inspection are included in the shipment. The delivery also includes applicable installation hardware.

The buckets are fully interchangeable with GE P/N 314B7162G015, without any modification to the gas turbine.

DESIGN LIFE
The estimated life is 72.000 EOH based on Ansaldo Thomassen recommendations and after standard inspection and repair intervals.