Method for the thermochemical cleaning and/or stripping of turbine components

Abstract

The invention relates to a process for the thermochemical cleaning and/or stripping of turbine components, in particular engine components, with the steps: Production of a first gaseous mixture containing HF and H 2 in which the part by volume of HF in the mixture of HF and H 2 is in the range of 2.5 to 45% by volume, and application of the first gaseous mixture containing HF and H 2 on and/or in a turbine component for cleaning and/or stripping this turbine component.

1 - 10 . (canceled) 
     
     
         11 . A method for the thermochemical cleaning and/or stripping of turbine components, in particular of engine components, the method comprising the following steps:
 production of a first gaseous mixture containing HF and H 2  in which the part by volume of HF in the mixture of HF and H 2  is in the range of 2.5 to 45% by volume;   application of the first gaseous mixture containing HF and H 2  on and/or in a turbine component for cleaning and/or stripping this turbine component; and   washing of the turbine component after the production and application of the first gaseous mixture on the turbine component by application of a second gaseous mixture or substance on and/or in the turbine component;   wherein the second gaseous mixture or substance contains HF and H 2  and the amount of HF in the mixture or substance of HF and H 2  measured in % by volume is less than in the first gaseous mixture.   
     
     
         12 . The method according to  claim 11 , wherein the part by volume of HF in the first gaseous mixture of HF and H 2  is in the range of 5 to 25% by volume. 
     
     
         13 . The method according to  claim 11 , wherein the second gaseous mixture or substance contains HF and H 2  and the amount of HF in the mixture or substance is in the range of 0.5 to 5% by volume. 
     
     
         14 . The method according to  claim 11 , wherein the first gaseous mixture and the second gaseous mixture or substance are applied on and/or in the turbine component in a multiply alternating manner. 
     
     
         15 . The method according to  claim 11 , wherein the pressure of at least one of the first gaseous mixture and the second gaseous mixture or substance is varied over time. 
     
     
         16 . The method according to  claim 11 , wherein the method is carried out in one of a container and a closed system. 
     
     
         17 . The method according to  claim 16 , wherein at least one of the first gaseous mixture and the second gaseous mixture or substance is supplied to the container and a chemical reaction is brought about by the first gaseous mixture and/or second gaseous mixture in the container that brings about a cleaning and/or stripping of the turbine component, and that the reaction products are subsequently removed partially or completely from the container. 
     
     
         18 . A method for the thermochemical cleaning/stripping of a component having unwanted material thereon, the method comprising the following steps:
 (a) applying a first gaseous substance containing HF and H 2  to the component to be cleaned/stripped, the first gaseous substance including a % by volume of HF in the range of 2.5 to 45% by volume;   (b) facilitating a reaction between the HF in the first gaseous substance and at least a portion of the unwanted material on the component such that at least a portion of the unwanted material is converted to a reaction product;   (c) applying a second gaseous substance containing HF and H 2  to the component to be cleaned/stripped, the second gaseous substance including a % by volume of HF that is less than the % by volume of HF in the first gaseous substance, whereby at least a portion of at least one of the first gaseous substance and the reaction product is washed from the component; and   (d) repeating steps (a)-(c) until a desired amount of the unwanted material is cleaned/stripped from the component.   
     
     
         19 . The method according to  claim 18 , wherein the component is disposed within a container having a volume and the first and second gaseous substances are successively introduced and removed from within the container. 
     
     
         20 . The method according to  claim 19 , wherein the step of applying a second gaseous substance (step (c)) further comprises removing the reaction products from the container with the second gaseous substance. 
     
     
         21 . The method according to  claim 19 , wherein the volume of first and second gaseous substances introduced and subsequently removed from the container during each hour is greater than 5 times the volume of the container. 
     
     
         22 . The method according to  claim 18 , wherein the component includes a hollow portion having a volume connected to a closed system and the first and second gaseous substances are successively introduced and removed from the closed system to the hollow portion of the component. 
     
     
         23 . The method according to  claim 22 , wherein the step of applying a second gaseous substance (step (c)) further comprises removing the reaction products from the hollow portion of the component with the second gaseous substance. 
     
     
         24 . The method according to  claim 22 , wherein the volume of first and second gaseous substances introduced and subsequently removed from the hollow portion of the component during each hour is greater than 5 times the volume of the hollow portion. 
     
     
         25 . The method according to  claim 18 , wherein the step of facilitating a reaction (step (b)) further includes varying the pressure of the first gaseous substance over time. 
     
     
         26 . The method according to  claim 25 , wherein the pressure fluctuations Δp of the first gaseous substance is within the range of Δp>5 mbar to Δp<200 mbar. 
     
     
         27 . The method according to  claim 25 , wherein the step of applying a second gaseous substance (step (c)) further comprises varying the pressure of the second gaseous substance over time. 
     
     
         28 . The method according to  claim 27 , wherein the pressure fluctuations Δp of the second gaseous susbstance is within the range of Δp>5 mbar to Δp<200 mbar. 
     
     
         29 . A method for the thermochemical cleaning/stripping of a component having unwanted material thereon, the method comprising the following steps:
 (a) providing a container having a volume;   (b) positioning the component within the container;   (c) introducing a first gaseous substance containing HF and H 2  into the container surrounding the component, the first gaseous substance including a % by volume of HF in the range of 2.5 to 45% by volume;   (d) varying the pressure of the first gaseous substance in the container with pressure fluctuations Δp within the range of Δp>5 mbar to Δp<200 mbar until a reaction between the HF in the first gaseous substance and at least a portion of the unwanted material on the component such that at least a portion of the unwanted material is converted to a reaction product;   (e) introducing a second gaseous substance containing HF and H 2  into the container surrounding the component, the second gaseous substance including a % by volume of HF that is less than the % by volume of HF in the first gaseous substance, whereby at least a portion of at least one of the first gaseous substance and the reaction product is washed from the component;   (f) removing at least a portion of the reaction products from the container; and   (g) repeating steps (a)-(f) until a desired amount of the unwanted material is cleaned/stripped from the component.   
     
     
         30 . The method according to  claim 29 , wherein the step of introducing a second gaseous substance (step (e)) further comprises varying the pressure of the second gaseous substance in the container with pressure fluctuations Δp within the range of Δp>5 mbar to Δp<200 mbar.