Patent ID: 7037381

Claim:
A method for removing ceramic coatings from surfaces of turbine airfoils, comprising the following steps: placing the airfoils in an autoclave preheated to at least a first preselected temperature; then providing a preselected volume of volatile organic fluid from a constant head storage container to a pro-heater for preheating the volatile organic fluid to a second preselected temperature near the first preselected temperature; introducing the preselected volume of preheated, pre-pressurized volatile fluid from the pre-heater into the autoclave with the airfoils; then providing a preselected volume of caustic-containing solution from a storage tank to the pre-heater for preheating the caustic solution to a third preselected temperature near the first preselected temperature; introducing the preselected volume of preheated, pre-pressurized caustic-containing solution into the autoclave with the volatile organic fluid and the airfoils; heating the autoclave to a fourth preselected temperature for a preselected period of time and at a preselected pressure sufficient to remove the ceramic coating from the airfoil surfaces; then withdrawing a gaseous phase of the volatile organic fluid from the autoclave to a condenser for condensation and cooling; directing the condensed, cooled volatile organic fluid to the constant head storage container; pre-filtering large ceramic particles from the caustic-containing solution, then while maintaining the autoclave at or above the first preselected temperature, removing the caustic-containing solution from the autoclave to the condenser for cooling; filtering smaller ceramic particles from the caustic-containing solution; and storing the caustic-containing solution in the storage tank.