Abstract:
A process is provided for welding a nickel or cobalt based superalloy article to minimize cracking by preheating the entire weld area to a maximum ductility temperature range, maintaining such temperature during welding and solidification of the weld, raising the temperature for stress relief of the superalloy, then cooling at a rate effective to minimize gamma prime precipitation.
Abstract:
PROBLEM TO BE SOLVED: To prevent the adhesion due to plating to cooling holes and to prevent a harmful affect to the flow of a cooling air by plating the outer surface of a component after pouring a masking material into the cooling path of the gas turbine engine component and charging plural cooling holes, and next removing the masking material. SOLUTION: The gas turbine engine component is pre-heated, the high temperature of molten masking material 5 is poured into cooling holes 4 under an effective pressure, and the masking material 5 is charged into the cooling path so as to be uniform with the surface of the component. Plating containing a noble metal of platinum or the like with a protective adhesive is applied on the outer surface of the component after aging and curing the masking material 5. The masking material 5 is removed after finishing plating. In the case of removing the masking material 5, the masking material 5 is removed by volatilizing with a high temperature added for an effective time. The masking material 5 is usually removed with the heat treatment of about 1,100-1,700 deg.F for 15-30 minutes and the surface of the super alloy being the component ins not harmfully affected with such temperature.
Abstract:
A process is provided to strip a metallic coating from a turbine blade comprising attaching the blade to a positive lead from a power supply, submersing a portion of the blade with a metallic coating to be stripped into a bath of acidic electro stripping solution, said bath containing a negative lead from a power supply attached to a conductive grid; and providing a current to the blade in the bath for a period of time effective to remove the coating on the portion of the blade.
Abstract:
A process is provided for welding a nickel or cobalt based superalloy article to minimize cracking by preheating the entire weld area to a maximum ductility temperature range, maintaining such temperature during welding and solidification of the weld, raising the temperature for stress relief of the superalloy, then cooling at a rate effective to minimize gamma prime precipitation.
Abstract:
A protective gas shroud (1) for welding is provided by: positioning an article (2) into a chamber (4) having an opening at the top to permit welding of the article; introducing argon (8) into the body of the chamber to act as a protective gas shroud for the article during welding; introducing helium (10) into the open top of the chamber to assist in maintaining a protective gas shroud around the article during welding; and welding the article within the protective gas shroud.
Abstract:
A blade tip cap of turbine blade is repaired by restoring the tip rail (4) and attaching a strengthening rib (5) across the blade tip cap connecting the concave wall to the convex wall of the tip rail.
Abstract:
A process is provided for welding a nickel or cobalt based superalloy article to minimize cracking by preheating the entire weld area to a maximum ductility temperature range, maintaining such temperature during welding and solidification of the weld, raising the temperature for stress relief of the superalloy, then cooling at a rate effective to minimize gamma prime precipitation.
Abstract:
A process is provided for plating a coating onto a gas turbine engine component without detrimentally effecting air flow through cooling holes by injecting a maskant into the cooling passage to fill the cooling holes with the maskant, plating the external surface of the component with a coating, then removing the maskant from the component.
Abstract:
A method for repairing a turbine blade (10) wherein the tip (16) of the blade is removed (41,43) and a replacement cap is attached by welding (49). The cap may consist of a plate (48) attached by welding and a squealer (54) formed by depositing weld material (52), as illustrated in FIG. 3. The plate and/or squealer may be formed from a material different from the material of the airfoil portion (42) of the blade in order to optimize the performance of the blade.
Abstract:
A process is provided for plating a coating onto a gas turbine engine component without detrimentally effecting air flow through cooling holes by injecting a maskant into the cooling passage to fill the cooling holes with the maskant, plating the external surface of the component with a coating, then removing the maskant from the component.