Airfoil with diffused cooling holes and method and apparatus for making the same
AssigneeChromalloy Gas Turbine Corporation
InventorsRichard J. Vertz, Reza K. Mosavi
Life of this patent
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Abstract
Air cooling of airfoils in a gas-turbine engine is effected through holes which terminate with a diffuser formation at the airfoil surface. The invention is directed to a two-step procedure whereby a laser beam drills the holes very quickly and cost-effectively and whereby an EDM step is relied upon only to form the diffuser shape. The EDM part of the procedure thus occupies but a fraction of the time previously required, and substantial overall economy is realized by integrating these two steps, which are preferably performed in the order stated but which, if desired, may alternatively be performed by laser driling after EDM formation of the diffuser shape.
Claims4
A body shell for a gas-turbine airfoil and having one or more cooling holes between an inner surface and an outer surface, each of said one or more holes having a laser-drilled inner bore portion and an EDM-machined outer diffuser portion, whereby the inner bore portion has a surface roughness which substantially exceeds the surface roughness of the outer diffuser portion.
A body shell for a gas-turbine airfoil and having one or more cooling holes between an inner surface and an outer surface, each of said one or more holes having an inner bore portion and an outer diffuser portion, said inner bore portion being the product of a laser-drilling process and said outer diffuser portion being the product of electric-discharge (EDM) machining.
Dependencies are inferred from the claim text.