Loading patent…
OwnerSalvatore J. Cretella, Matthew Bernardo +1inventors
InventorsSalvatore J. Cretella, Matthew Bernardo, Ralph T. DeMusis
Estimating the term…
A method for repairing turbine vanes and the like which have become worn or cracked after extended periods of use. The method embraces the steps of applying molten metal containing a predetermined quantity of silicon to the cracks, and overall to the worn or eroded areas of the vane to build up the same beyond its original surface, sintering the vane in a furnace at a temperature of over 2,000.degree. F thereby burning off some of the silicon, allowing the vane to cool, and thereafter placing it in a high pressure furnace and subjecting it simultaneously to heating to a temperature in excess of 2,000.degree. F and a pressure in excess of 15,000 PSI to drive the build-up material into all of the cracks of the vane and simultaneously effect a densification of the material as well as improving the bond to the original eroded surfaces. Thereafter the vane is removed and allowed to cool, and the built-up surface of the vane is ground down so as to restore the dimensions of the piece substantially to those of a new part.
The method of refurbishing an airfoil-shaped metal alloy turbine part having a composition containing substantial quantities of cobalt, chromium, tungsten and nickel, with silicon present in an amount less than several percent, comprising the steps of mixing a preparation of an overlay metal alloy comprising substantially the same respective amounts of cobalt, chromium, tungsten and nickel as contained in said turbine part and with silicon present in an amount less than several percent, adding to said preparation an amount of silicon equal to essentially at least ten percent of the silicon content of the preparation, converting said preparation and added silicon into a molten alloy, applying said molten alloy to the eroded surfaces of the airfoil part to build-up the same beyond its original surface, sintering the airfoil part in a furnace at a temperature above 2,000.degree. F and burning off substantially all of the added silicon contained in the molten alloy that was applied to said part such that the resultant overlay alloy has substantially the same composition as the turbine part, removing and cooling the airfoil part, placing the airfoil part in a high pressure furnace, and heating the airfoil part to a temperature above 2,000.degree. F and simultaneously applying thereto a pressure in excess of 15,000 PSI, thereby effecting a densification of the applied overlay alloy and an improved bond of the applied alloy to the eroded airfoil surfaces, removing the airfoil part and cooling the same, and grinding the overlay surface of the airfoil part to restore the dimensions thereof substantially to those of a new part.
Dependencies are inferred from the claim text.