阅读说明：本技术 用于选择性清洁涡轮发动机构件的系统和方法 (System and method for selectively cleaning turbine engine components ) 是由 N.J.蒂贝茨 A.J.詹金斯 B.P.布莱 E.J.多利 J.瓦特 C.佩雷特 V.G 于 2018-06-13 设计创作，主要内容包括：提供一种用于使清洁组分选择性地接触涡轮发动机构件的表面的系统。系统包括清洁设备和歧管组件。清洁设备包括限定清洁室的上部部分和下部部分,清洁室构造成允许在清洁组分和涡轮发动机构件的第一部分的表面之间有选择性接触。上部部分包括与清洁室处于流体连通的多个充注孔,而下部部分包括与清洁室处于流体连通的多个排出孔。歧管组件构造成选择性地使清洁组分从贮存器经由多个充注孔循环到清洁室,且使清洁组分从清洁室经由多个排出孔再循环到贮存器。还提供用于选择性地清洁涡轮发动机构件的方法。(A system for selectively contacting a cleaning composition with a surface of a turbine engine component is provided. The system includes a cleaning apparatus and a manifold assembly. The cleaning apparatus includes an upper portion and a lower portion defining a cleaning chamber configured to allow selective contact between a cleaning component and a surface of a first portion of a turbine engine component. The upper portion includes a plurality of fill apertures in fluid communication with the cleaning chamber, and the lower portion includes a plurality of drain apertures in fluid communication with the cleaning chamber. The manifold assembly is configured to selectively circulate the cleaning component from the reservoir to the cleaning chamber via the plurality of fill apertures and to recirculate the cleaning component from the cleaning chamber to the reservoir via the plurality of drain apertures. Methods for selectively cleaning turbine engine components are also provided.)

1. A method for selectively cleaning a surface of a turbine engine component, comprising:

(I) applying a cleaning cycle to the surface of the turbine engine component, the cleaning cycle comprising sequentially contacting the surface of the turbine engine component with an alkaline component, a first acidic component, a first alkali permanganate component, and a second acidic component;

(II) selectively contacting a first portion of the surface of the turbine engine component with a second alkali permanganate component; and

(III) selectively contacting the first portion of the surface of the turbine engine component with a surface having at least 10⁴A cleaning component of poise viscosity comprising a third acidic component, an active compound, and a thickener;

wherein steps (II) and (III) are accomplished such that a remaining second portion of the surface of the turbine engine component does not contact the second alkali permanganate component and the cleaning component.

2. The method of claim 1, wherein the third acidic component comprises nitric acid, phosphoric acid, sulfuric acid, hydrochloric acid, acetic acid, or a combination thereof.

3. The method of claim 1, wherein the active compound comprises an iron salt.

4. The method of claim 1, wherein the thickener comprises a plurality of particulate components comprising silica, titanium dioxide, or a combination thereof.

5. The method of claim 1, wherein the cleaning component comprises hydrochloric acid, ferric chloride, and fumed silica.

6. The method of claim 1, wherein the cleaning component comprises nitric acid, sulfuric acid, hydrochloric acid, acetic acid, ferric chloride, and fumed silica.

7. The method of claim 1, wherein the turbine engine component comprises a turbine disk, a turbine blade, a compressor disk, a compressor blade, a compressor shaft, a rotary seal, a frame, or a casing.

8. The method of claim 1, wherein the first portion of the surface of the turbine engine component comprises a surface of a dovetail portion of a turbine disk.

Technical Field

Embodiments of the present disclosure generally relate to systems and methods for selectively cleaning turbine engine components. More specifically, embodiments of the present disclosure relate to systems and methods for selectively cleaning turbine engine components using a viscous cleaning composition.

Background

As the maximum operating temperature of the gas turbine engine increases, components of the gas turbine engine (e.g., the turbine disk, shaft, or sealing element) experience higher temperatures. Thus, oxidation and corrosion of these components have become increasingly of concern. Turbine engine components for use at such high operating temperatures are typically made of nickel and/or cobalt-based superalloys selected for good high temperature and fatigue resistance. These superalloys are resistant to oxidation and corrosion damage, but the resistance is insufficient to fully protect them at the operating temperatures currently reached. Over time, engine deposits such as (but not limited to) nickel oxide and/or aluminum oxide may form coatings or layers on the surfaces of these turbine components. These engine deposits typically need to be cleaned off or otherwise removed. Other components, particularly those operating at relatively low temperatures, may be made of other alloy types, such as titanium or steel; these components may also be oxidized during operation.

Further, certain components of the turbine engine may need to be inspected for defects (e.g., cracks formed) during their operating life. However, the effectiveness of typical techniques used to perform inspection (e.g., crack detection) may be affected by the presence of oxides on the metal surfaces of these components. Typical cleaning methods used to remove these oxides prior to inspection may require one or more of the following: abrasive cleaning techniques (e.g., abrasive wet blasting), multiple cleaning cycles, a volume of cleaning fluid, or manually applying a cleaning fluid to a component to be cleaned. Thus, conventional cleaning techniques can present a variety of challenges, such as cost inefficiency, cumbersome use, and additional environmental and health safety concerns.

Furthermore, cleaning operations for gas turbine engines typically employ chemical means, such as acid solutions, to remove oxides and other engine deposits from the components. While such techniques may be effective, they are challenging to effectively apply in situations where it is desirable to limit the area of the cleaning component contacting the member used to remove the deposits. For example, some components include multiple materials, wherein one or more of the materials may be incompatible with the cleaning component. As another example, in some components, deposits tend to form only at certain locations, while other locations of the component remain acceptably free of deposits. In some cases, such as those in which selective exposure of only the component areas to cleaning components is desired, typical processes require additional steps, such as component disassembly, masking processes, or other techniques that necessitate re-application of dimensional build material and increase the time and expense of the overall cleaning process.

Accordingly, it would be desirable to be able to effectively and efficiently clean and remove engine deposits, particularly engine deposits comprising metal oxides, from turbine engine components. It would be particularly desirable to be able to selectively clean and remove such engine deposits in a manner that does not excessively or significantly remove or alter the base metal of the component. It would further be desirable to have a cleaning system and method that allows for effective and efficient cleaning of engine deposits in a selective manner.

Disclosure of Invention

In one aspect, the present disclosure is directed to a system for selectively contacting a cleaning component with a surface of a turbine engine component. The system includes a cleaning apparatus and a manifold assembly. The cleaning apparatus includes an upper portion and a lower portion that collectively define a cleaning chamber. The cleaning chamber is configured to receive a first portion of the turbine engine component and allow selective contact between the cleaning component and a surface of the first portion of the turbine engine component. The upper portion includes a plurality of fill apertures in fluid communication with the cleaning chamber, and the lower portion includes a plurality of drain apertures in fluid communication with the cleaning chamber. The manifold assembly is in fluid communication with the plurality of fill holes and the plurality of drain holes. The manifold assembly is configured to selectively circulate the cleaning component from the reservoir to the cleaning chamber via the plurality of fill apertures and to recirculate the cleaning component from the cleaning chamber to the reservoir via the plurality of drain apertures.

In another aspect, the present disclosure is directed to a method for selectively contacting a cleaning component with a surface of a turbine engine component. The method includes disposing a first portion of a turbine engine component in a cleaning chamber of a cleaning apparatus, the cleaning chamber defined by an upper portion and a lower portion of the cleaning apparatus. The method further includes circulating the cleaning composition from the reservoir to the cleaning chamber via the manifold assembly and a plurality of fill holes disposed in an upper portion of the cleaning apparatus. The method further includes selectively contacting the cleaning component with a surface of the first portion of the turbine engine component. The method further includes recirculating the cleaning composition from the cleaning chamber to the reservoir via the manifold assembly and a plurality of drain holes disposed in a lower portion of the cleaning apparatus.

In yet another aspect, the present disclosure is directed to a method for selectively cleaning a surface of a turbine engine component. The method comprises the following steps: (I) a cleaning cycle is applied to a surface of a turbine engine component, the cleaning cycle comprising sequentially contacting the surface of the turbine engine component with an alkaline component, a first acidic component, a first alkali permanganate component, and a second acidic component. The method further comprises the following steps: (II) selectively contacting a first portion of the surface of the turbine engine component with a second alkali permanganate component. The method further comprises: (III) selectively contacting a first portion of a surface of a turbine engine component with a surface having at least 10⁴A poise viscosity, the cleaning component comprising a third acidic component, an active compound, and a thickener. Steps (I) and (II) are accomplished such that the remaining second portion of the surface of the turbine engine component is substantially free of contactA second alkali metal permanganate component and a cleaning component.

Technical solution 1. a system for selectively contacting a cleaning composition to a surface of a turbine engine component, comprising:

a cleaning apparatus, comprising:

an upper portion and a lower portion that collectively define a cleaning chamber configured to receive a first portion of the turbine engine component and allow selective contact between the cleaning component and a surface of the first portion of the turbine engine component,

the upper portion includes a plurality of fill apertures in fluid communication with the cleaning chamber and the lower portion includes a plurality of drain apertures in fluid communication with the cleaning chamber; and

a manifold assembly in fluid communication with the plurality of fill apertures and the plurality of drain apertures, the manifold assembly configured to selectively circulate the cleaning component from a reservoir to the cleaning chamber via the plurality of fill apertures and to recirculate the cleaning component from the cleaning chamber to the reservoir via the plurality of drain apertures.

The system of claim 1, wherein the upper portion and the lower portion further define a sheltering chamber for receiving a second portion of the turbine engine component, the sheltering chamber and the cleaning chamber being fluidly sealed from one another via a sealing mechanism such that a surface of the second portion of the turbine engine component does not substantially contact the cleaning component.

The system of claim 3, wherein the upper portion further comprises a plurality of vents in fluid communication with the cleaning chamber and the manifold assembly is in fluid communication with the plurality of vents and is further configured to circulate a cleaning composition to and from the cleaning chamber via the plurality of vents and the plurality of drain holes.

Solution 4. the system of solution 1, wherein the manifold assembly and the cleaning component comprise the cleaning componentThe reservoirs are in fluid communication and the cleaning component has at least 10⁴Viscosity of poise.

Solution 5. the system of solution 1 wherein the turbine engine component comprises a turbine disk, a turbine blade, a compressor disk, a compressor blade, a compressor shaft, a rotary seal, a frame or a casing.

The system of claim 1, wherein the first portion of the turbine engine component comprises a dovetail portion of a turbine disk.

Solution 7. a method for selectively contacting a cleaning composition with a surface of a turbine engine component, comprising:

disposing a first portion of the turbine engine component in a cleaning chamber of a cleaning apparatus, the cleaning chamber defined by an upper portion and a lower portion of the cleaning apparatus;

circulating the cleaning component from a reservoir to the cleaning chamber via a manifold assembly and a plurality of fill holes disposed in the upper portion of the cleaning apparatus;

selectively contacting the cleaning component with a surface of the first portion of the turbine engine component; and

recirculating the cleaning component from the cleaning chamber to the reservoir via the manifold assembly and a plurality of drain holes disposed in the lower portion of the cleaning apparatus.

The method of claim 8, 7, wherein the disposing step further comprises disposing the second portion of the turbine engine component in a sheltering chamber defined by the upper portion and the lower portion of the cleaning apparatus; the masking chamber and the cleaning chamber are fluidly sealed from each other via a sealing mechanism such that a surface of the second portion of the turbine engine component does not substantially contact the cleaning component during the circulating and contacting steps.

Solution 9. the method of solution 7, further comprising circulating a cleansing component from a cleansing reservoir to the cleansing chamber via a manifold assembly and a plurality of vent holes disposed in the upper portion of the cleansing apparatus, and recirculating the cleansing component from the cleansing chamber to the cleansing reservoir via the manifold assembly and a plurality of drain holes disposed in the lower portion of the cleansing apparatus.

Solution 10. the method of solution 7, wherein the cleaning composition has at least 10⁴Viscosity of poise.

Solution 11. the method according to solution 7, wherein the cleansing component comprises an acid, an active compound, and a thickening agent.

Solution 12. the method of solution 7 wherein the turbine engine component comprises a turbine disk, a turbine blade, a compressor disk, a compressor blade, a compressor shaft, a rotary seal, a frame, or a casing.

The method of claim 7, wherein the first portion of the turbine engine component comprises a dovetail portion of a turbine disk.

Technical solution 14. a method for selectively cleaning a surface of a turbine engine component, comprising:

(I) applying a cleaning cycle to the surface of the turbine engine component, the cleaning cycle comprising sequentially contacting the surface of the turbine engine component with an alkaline component, a first acidic component, a first alkali permanganate component, and a second acidic component;

(II) selectively contacting a first portion of the surface of the turbine engine component with a second alkali permanganate component; and

(III) selectively contacting the first portion of the surface of the turbine engine component with a surface having at least 10⁴A cleaning component of poise viscosity comprising a third acidic component, an active compound, and a thickener;

wherein steps (II) and (III) are accomplished such that a remaining second portion of the surface of the turbine engine component does not substantially contact the second alkali permanganate component and the cleaning component.

Claim 15 the method of claim 14, wherein the third acidic component comprises nitric acid, phosphoric acid, sulfuric acid, hydrochloric acid, acetic acid, or a combination thereof.

Solution 16. the method according to solution 14, wherein the active compound comprises an iron salt.

The method of claim 14, wherein the thickening agent comprises a plurality of particulate components, the particulate components comprising silica, titanium dioxide, or a combination thereof.

Solution 18. the method according to solution 14, wherein the cleaning component comprises hydrochloric acid, ferric chloride and fumed silica.

Technical solution 19. the method according to claim 14, wherein the cleaning component comprises nitric acid, sulfuric acid, hydrochloric acid, acetic acid, ferric chloride, and fumed silica.

Solution 20. the method of solution 14, wherein the turbine engine component comprises a turbine disk, a turbine blade, a compressor disk, a compressor blade, a compressor shaft, a rotary seal, a frame, or a casing.

The method of claim 14, wherein the first portion of the surface of the turbine engine component comprises a surface of a dovetail portion of a turbine disk.

These and other features, embodiments and advantages of the present disclosure may be more readily understood by reference to the following detailed description.

Drawings

These and other features, aspects, and advantages of the present disclosure will become better understood when the following detailed description is read with reference to the accompanying drawings, wherein:

FIG. 1A illustrates an example of a turbine engine component according to some embodiments of the present disclosure;

FIG. 1B illustrates an enlarged view of a portion of a turbine engine component, according to some embodiments of the present disclosure;

FIG. 2 illustrates a line drawing of a system for selectively contacting a cleaning composition to a surface of a turbine engine component, according to some embodiments of the present disclosure;

FIG. 3 illustrates a schematic view of a system for selectively contacting a cleaning component to a surface of a turbine engine component, according to some embodiments of the present disclosure;

FIG. 4A illustrates a cross-sectional view of a system for selectively contacting a cleaning component to a surface of a turbine engine component, according to some embodiments of the present disclosure;

FIG. 4B illustrates an enlarged portion of a cross-sectional view of a system for selectively contacting a cleaning component to a surface of a turbine engine component, according to some embodiments of the present disclosure;

FIG. 5 illustrates a schematic view of a system for selectively contacting a cleaning component to a surface of a turbine engine component, according to some embodiments of the present disclosure;

FIG. 6 illustrates a flow diagram of a method for selectively contacting a cleaning component to a surface of a turbine engine component, according to some embodiments of the present disclosure; and

FIG. 7 illustrates a flow diagram of a method for selectively contacting a cleaning component to a surface of a turbine engine component, according to some embodiments of the present disclosure.

Detailed Description

In the following specification and the claims which follow, reference will be made to a number of terms which shall be defined to have the following meanings. The singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. As used herein, the term "or" is not meant to be exclusive, but rather indicates the presence of at least one of the referenced components and includes instances where a combination of the referenced components is present, unless the context clearly dictates otherwise.

Approximating language, as used herein in the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as "about" and "substantially", are not to be limited to the precise value specified. In some cases, the approximating language may correspond to a perusal of an instrument for measuring the value. Similarly, "none" may be used in combination with an item, and may include trace amounts or trace amounts, while still being considered an unmodified item. Here and in the specification and claims, range limitations may be combined and/or interchanged, such ranges are identified and include all the sub-ranges contained therein unless context or language indicates otherwise.

The systems and methods described herein address, at least in part, the noted shortcomings in conventional cleaning methods and systems by using cleaning components having a high viscosity relative to conventional liquid cleaning components. The viscous component substantially remains in the area of the component on which the viscous component is disposed during the cleaning process, thereby providing the ability to clean selected areas of the turbine engine component without unduly exposing adjacent areas where exposure to the cleaning component is undesirable or incompatible with the component material. Further, by employing the systems and methods described herein, selective cleaning of turbine engine components may be achieved while achieving one or more of the following: (i) limiting contact of the cleaning component to the area requiring cleaning, (ii) efficiently and effectively cleaning portions of the turbine engine component, (iii) minimizing contact time of the cleaning component, thereby minimizing corrosion, (iv) reusing the cleaning component, thereby reducing the amount required, (v) minimizing human contact with the cleaning component and the effluent stream, and (vi) collecting the effluent stream in a substantially harmless manner.

A system for selectively contacting a cleaning composition with a surface of a turbine engine component is provided. A turbine engine denotes any engine in which a turbine is driven by combustion products of air and fuel. In some embodiments, the turbine engine may be an aircraft engine. Alternatively, the turbine engine may be any other type of engine used in industrial applications. Non-limiting examples of such turbine engines include land-based turbine engines used in power plants, turbine engines used in marine vessels, or turbine engines used in drilling platforms. The terms "gas turbine engine" and "turbine engine" are used interchangeably herein.

As used herein, the term "turbine engine component" refers to a wide variety of turbine engine (e.g., gas turbine engine) parts and components on the surface of which engine deposits may need to be removed during normal engine operation. The methods and systems described herein are particularly useful when applied to engine components that may oxidize during operation, but it will be understood that this is not a necessary limitation on the scope of the methods and systems.

Non-limiting examples of turbine engine components that may be cleaned by the methods and systems disclosed herein include, but are not limited to, turbine disks, turbine blades, compressor disks, compressor blades, compressor shafts, rotary seals, frames, or casings.

In some embodiments, the turbine engine component is or includes a turbine disk for a turbine engine assembly. As is well known, such discs have a generally annular shaped hub portion and an outermost rim portion (referred to herein as a "dovetail region") shaped as a plurality of dovetails for engaging a corresponding plurality of turbine blades. In certain embodiments, as described in detail below, the methods and systems described herein are particularly useful for removing engine deposits from the surfaces of multiple dovetail sections of a turbine disk. As used herein, the term "dovetail portion" means some or all of the dovetail region. FIG. 1A shows an example turbine disk 100 including a hub portion 110 and an outermost rim portion 120. As shown in fig. 1A, outermost rim portion 120 includes a plurality of dovetail regions 122. In some embodiments, the portion of the turbine engine component that is selectively contacted by the cleaning composition comprises at least a portion of the plurality of dovetail regions 122, according to the methods and systems described herein.

Similarly, a turbine blade (not shown in the figures) typically includes a dovetail portion in the region of the blade that engages the disk. In some embodiments, the dovetail portions of the blades (again, some or all of the dovetail portions) can be selectively contacted with cleaning components using the methods and systems described herein. In yet another example, the turbine engine component is or includes a casing or frame (not shown in the figures) for a compressor or turbine. For example, low pressure turbine casings have design features called rails on which mating components rest, the rails oxidizing because they extend into the hot gas path and are difficult to clean. In some embodiments, the track portions of the housings may be selectively contacted with the cleaning component using the methods and systems described herein.

The turbine engine component comprises a metal. In some embodiments, the turbine engine component comprises a superalloy, a steel such as stainless steel, a titanium alloy, or other metals commonly used in engine components. In certain embodiments, the turbine engine component comprises a superalloy, such as a nickel-based superalloy, an iron-based superalloy, a cobalt-based superalloy, or a combination thereof. Illustrative nickel or cobalt-based superalloys are identified by the trade names INCONEL (e.g., INCONEL 718), NIMONIC, RENE (e.g., RENE 88, RENE 104 alloy), HAYNES, and UDIMET. For example, an alloy that may be used to make turbine disks, turbine shafts, and other useful components is a nickel-based superalloy available under the trade name INCONEL 718, having a nominal composition, by weight, of 52.5% nickel, 19% chromium, 3% molybdenum, 3.5% manganese, 0.5% aluminum, 0.45% titanium, 5.1% combined tantalum and niobium, and 0.1% or less carbon, with the balance being iron. As another example, a nickel-based superalloy available under the trade name RENE 88DT has a nominal composition, by weight, of 13% cobalt, 16% chromium, 4% molybdenum, 4% tungsten, 2.1% aluminum, 3.7% titanium, 0.7% niobium, 0.03% carbon, and 0.015% boron.

As used herein, the term "engine deposits" refers to those deposits that form as coatings, layers, scale, etc. on the surfaces of the turbine components over time during operation of the gas turbine engine. These engine deposits typically include oxides of the base metal. In some embodiments, the oxide comprises a material formed from oxidation of a metal of the engine component during operation or manufacture, meaning that the oxide comprises at least one element derived from the metal of the turbine engine component. By way of example, where the turbine engine component comprises a nickel alloy, the oxide at the surface of the turbine engine component may comprise nickel, such as nickel oxide or a spinel comprising nickel and other elements such as chromium, aluminum, or combinations thereof. Highly alloyed superalloys such as RENE 88DT, RENE 104, and the like, for example, have been found to have increasingly complex oxides with increasing alloy content, for example, mixtures of cobalt oxide and spinel and titanium oxides in addition to nickel or chromium or aluminum oxides more typically seen. The properties of the oxide will depend in part on the composition of the metal at the surface of the turbine engine component and the environmental conditions (e.g., temperature, atmosphere) under which the oxide is formed.

The system includes a cleaning apparatus and a manifold assembly. The cleaning apparatus includes an upper portion and a lower portion that together define a cleaning chamber. The cleaning chamber is configured to receive a first portion of the turbine engine component and allow contact between the cleaning component and a surface of the first portion of the turbine engine component. The upper portion includes a plurality of fill apertures in fluid communication with the cleaning chamber, and the lower portion includes a plurality of drain apertures in fluid communication with the cleaning chamber. The manifold assembly is in fluid communication with the plurality of fill holes and the plurality of drain holes. The manifold assembly is configured to selectively circulate the cleaning component from the reservoir to the cleaning chamber via the plurality of fill apertures and to recirculate the cleaning component from the cleaning chamber to the reservoir via the plurality of drain apertures.

Fig. 2 and 3 illustrate a system 200 for selectively contacting a cleaning composition 10 to a surface of a turbine engine component, according to some embodiments of the present disclosure. Fig. 2 shows a line drawing of a system 200 and fig. 3 shows a schematic of an example system 200 according to some embodiments of the present disclosure. The system 200 includes a cleaning apparatus 210 and a manifold assembly 220. The cleaning device 210 includes an upper portion 211 and a lower portion 212. As shown in fig. 2, the upper portion 211 and the lower portion 212 collectively define a cleaning chamber 213. The cleaning chamber is configured to receive a first portion of a turbine engine component (not shown in FIG. 2) and allow contact between the cleaning component and a surface of the first portion of the turbine engine component. It should be noted that the terms "upper portion" and "lower portion" are used herein only for ease of description and do not imply any particular orientation of the two portions. In some embodiments, the terms "upper portion" and "lower portion" may be described in the context of a surface of a turbine engine component that requires cleaning. For example, in some such cases, the "upper portion" may represent the portion of the cleaning apparatus that will be proximate to the surface to be cleaned. In some embodiments, the upper portion and the lower portion are removably coupled to each other.

Further, as shown in fig. 2 and 3, the upper portion 211 includes a plurality of fill apertures 201 in fluid communication with the cleaning chamber 213, while the lower portion 212 includes a plurality of drain apertures 202 in fluid communication with the cleaning chamber 213. It should be noted that the number, shape, size and location of the fill apertures 201 and vent apertures 202 in fig. 2 and 3 are for illustrative purposes only. One or more of the above design characteristics of the fill aperture 201 and the drain aperture 202 may vary based at least in part on one or more of the following: the shape and size of the surface to be cleaned, the desired contact time, the cleaning composition 10 characteristics (e.g., viscosity, amount, temperature, etc.), and the pressure applied to circulate the cleaning composition 10. In some embodiments, the number of filling holes 201 in upper portion 211 may range from about 4 to about 12. In some embodiments, the number of exhaust holes 202 in the lower portion 212 may range from about 4 to about 12. Further, filling aperture 201 and venting aperture 202 may be directly aligned with one another, or alternatively, may be staggered with respect to one another.

The manifold assembly 220 is in fluid communication with the plurality of fill apertures 201 and the plurality of drain apertures 202. As used herein, the term "in fluid communication with" means that two components or parts of the system (e.g., the manifold assembly and the fill port) can transfer fluid from one component or part to another component or part, either directly or through the use of intervening components (e.g., tubes, pipes, valves, etc.).

Further, as shown in fig. 2 and 3, manifold assembly 220 is configured to selectively circulate cleaning composition 10 from reservoir 250 to cleaning chamber 213 via a plurality of fill apertures 201, and to recirculate cleaning composition 10 from cleaning chamber 213 to reservoir 250 via a plurality of drain apertures 202. The manifold assembly 220 may be fluidly coupled to the fill aperture 201 and the drain aperture 202 via one or more of tubes, pipes, or the like. In certain embodiments, the manifold assembly 220 is in fluid communication with the plurality of fill apertures 201 and the plurality of drain apertures 202 via the plurality of tubes 215 and 216, respectively. For ease of illustration, fig. 2 and 3 show only two tubes 215 and 216. However, system 200 may include a plurality of tubes 215 for circulating cleaning composition 10 from reservoir 250 to fill aperture 201, and similarly may include a plurality of tubes 216 for recirculating cleaning composition 10 from drain aperture 202 to reservoir 250. In some embodiments, the system includes the same number of tubes 215 as the number of fill holes 201 for circulating the cleaning composition 10. In some embodiments, the system includes a fewer number of tubes 215 than the number of fill holes 201 for circulating the cleaning composition 10. In some embodiments, the system includes the same number of tubes 216 as the number of drain holes 202 for recirculating the cleaning composition 10. In some embodiments, the system includes a fewer number of tubes 216 than the number of discharge holes 202 for recirculating the cleaning composition 10.

The manifold assembly 220 may be in fluid communication with the reservoir 250 via a suitable mechanism, such as a tube, pipe, or the like. In the embodiment shown in fig. 2 and 3, the manifold assembly is fluidly coupled to reservoir 250 via conduits 217 and 218. The inflow and outflow of cleaning composition 10 to and from manifold assembly 220 may be further controlled by suitable fluid control mechanisms, such as valves.

In some embodiments, the cleaning chamber 213 may feature a geometry and volume such that a first portion of a turbine engine component may be easily housed in the cleaning chamber 213. Accordingly, the configuration of the cleaning chamber 213 may be designed and manufactured depending on the geometry and configuration of the turbine engine component to be cleaned. As will be apparent to one of ordinary skill in the art, the geometry and configuration of the cleaning chamber 213 may be changed by changing the geometry and configuration of the upper portion 211 and the lower portion 212 of the cleaning apparatus 210.

In some embodiments, the cleaning chamber 213 may be configured to receive at least a portion of different types of gas turbine engine components, non-limiting examples of which include turbine disks, turbine blades, compressor disks, compressor blades, compressor shafts, rotary seals, frames, or casings. In some embodiments, the cleaning chamber 213 may be configured to receive a dovetail region of a turbine disk. In certain embodiments, the cleaning chamber 213 may be configured to receive a plurality of such dovetail-shaped regions of a turbine disk.

As previously mentioned, the systems and methods described herein allow for selective cleaning of surfaces of turbine engine components without having to use component disassembly or cumbersome masking techniques. In some embodiments, the system 200 described herein may allow for the selective application of the cleaning composition 10 to the surface of a turbine engine component by allowing only certain portions of the turbine engine component to be contacted by the cleaning composition 10. Thus, the remaining portions of the turbine engine component are effectively masked without having to use an additional masking system.

Referring now to fig. 4A and 4B, a schematic diagram of a cross-sectional view of the cleaning apparatus 210 and an enlarged view of a portion of the cleaning apparatus 210 are shown, respectively. The cleaning apparatus 210 includes an upper portion 211 and a lower portion 212 that define a cleaning chamber 213. The upper portion further comprises a plurality of fill holes 201. In the embodiment shown in fig. 4A and 4B, a first portion of a turbine engine component is disposed in the clean room 213. In the example embodiment, the turbine engine component is a turbine disk 100 (shown in FIG. 1), and the first portion of the turbine engine component is a dovetail region 122 of the turbine disk 100. It should be noted that only one dovetail region 122 is shown in fig. 4A and 4B for purposes of illustration, however, a plurality of such dovetail regions 122 may be provided in the cleaning chamber, e.g., arranged circumferentially.

Referring again to fig. 4A and 4B, the upper portion 211 and the lower portion 212 of the cleaning apparatus 210 further define a masking chamber 214. The shroud chamber is configured to receive a second portion of the turbine engine component. In the example shown in fig. 4A and 4B, the second portion is a hub portion 110 of the turbine disc 100 (shown in fig. 1). The masking chamber 214 and the cleaning chamber 213 are fluidly sealed from each other via a sealing mechanism 230 such that a surface of the second portion of the turbine engine component does not substantially contact the cleaning composition 10. That is, for example, the hub portion 110 of the turbine disk 100 does not substantially contact the cleaning composition 10. Thus, by employing the cleaning apparatus configuration according to embodiments of the present disclosure, selective contact and cleaning of turbine engine components may be achieved in an efficient and effective manner. In some embodiments, the cleaning device 210 has a clamshell configuration. Any suitable sealing mechanism may be used so long as the sealing mechanism is capable of fluidly sealing the masking chamber 214 and the cleaning chamber 213. In some embodiments, a gasket may be employed as the sealing mechanism 230.

Referring now to fig. 5, in some embodiments, the upper portion 211 further comprises a plurality of vents 203 in fluid communication with the cleaning chamber 213. As shown in fig. 5, the manifold assembly 220 is in fluid communication with a plurality of vents 203 and a wash reservoir 260. The manifold assembly 220 is further configured to circulate the cleaning composition 20 to and from the cleaning chamber 213 via the plurality of vent holes 203 and the plurality of drain holes 202, as shown in fig. 5. The cleaning composition 20 comprises any suitable rinsing fluid that may rinse any residual cleaning composition from one or both of the cleaning chamber 213 and the surfaces of the turbine engine components after cleaning is achieved. It should be noted that the number, shape, size and location of the vent holes in fig. 5 are for illustration purposes only. In some embodiments, the number of vent holes in the upper portion 211 may range from about 4 to about 12. Further, the vent holes 203 and the exit holes 202 may be directly aligned with each other, or alternatively, may be staggered with respect to each other. In some embodiments, upper portion 211 may include alternating filling holes 201 and vent holes 203.

The manifold assembly 220 may be fluidly coupled to the vent 203 via one or more of a tube, a conduit, or the like. In certain embodiments, the manifold assembly 220 is in fluid communication with the plurality of vents 203 via a plurality of tubes 219. Fig. 5 shows only two tubes 219 for ease of illustration. However, the system 200 may include a plurality of tubes 219. In some embodiments, the system includes the same number of tubes 219 as the number of vents 203 for circulating the cleaning composition 20. In some embodiments, the system includes a fewer number of tubes 219 than the number of vents 203 for circulating the cleaning composition 20.

The manifold assembly 220 may be in fluid communication with the wash reservoir 260 via a suitable mechanism, such as a tube, pipe, or the like. In the embodiment shown in fig. 5, the manifold assembly is fluidly coupled to the wash reservoir via conduit 221. The inflow and outflow of the cleaning composition 20 into and out of the manifold assembly 220 may be further controlled by suitable fluid control mechanisms, such as, for example, valves.

In some embodiments, the vent may further facilitate one or both of: (1) avoiding or minimizing pressure build-up in the cleaning chamber while the cleaning chamber is being filled with a cleaning composition; and (2) monitoring the level of the cleaning component in the cleaning chamber by observing the cleaning component reaching a vent on the top of the cleaning device, which may indicate that the cleaning chamber is filled without any trapped air pockets and that the entire first portion is submerged in the cleaning component.

In some embodiments, the system 200 further includes a suitable pressurization mechanism (e.g., a pump) 270 for circulating the cleaning composition 10 to and from the cleaning chamber 213 via a manifold assembly, as shown in fig. 3 and 5.

In some embodiments, a method for selectively contacting a cleaning component with a surface of a turbine engine component is also provided. The method includes disposing a first portion of a turbine engine component in a cleaning chamber of a cleaning apparatus, the cleaning chamber defined by an upper portion and a lower portion of the cleaning apparatus. The method further includes circulating the cleaning composition from the reservoir to the cleaning chamber via the manifold assembly and a plurality of fill holes disposed in an upper portion of the cleaning apparatus. The method further includes selectively contacting the cleaning component with a surface of the first portion of the turbine engine component. The method further includes recirculating the cleaning composition from the cleaning chamber to the reservoir via the manifold assembly and a plurality of drain holes disposed in a lower portion of the cleaning apparatus.

3-6, a method 1000 for cleaning a gas turbine engine is shown, according to one embodiment. As shown in fig. 3-6, in some embodiments, at step 1001, the method includes disposing a first portion of a turbine engine component in the cleaning chamber 213 of the cleaning apparatus 210. As previously described in detail, the first portion of the turbine engine component may include any portion that requires selective cleaning.

In some embodiments, the surface of the turbine engine component to be cleaned may be prepared prior to contact with the cleaning composition 10. For example, loosely adhered dust and other debris may be mechanically removed by any means commonly used in the art, such as by directing a jet of air or liquid onto a surface, by scraping or brushing, or by any other convenient technique. In some embodiments, the method further comprises a preparation step comprising applying a chemical formulation to the surface. The application of the chemical formulation may be additional or alternative to mechanical removal of the deposit. Various products for removing oil and solid deposits from engine components are commercially available, such as those under the trade name TURCO. An example of such a chemical formulation is the TURCO 4338 brand compound (commercially available from Henkel), an alkali metal permanganate formulation. Other non-limiting examples of commercially available chemical formulations include Ardrox185L, Ardrox1873, Ardrox1218, and Ardrox1435 (commercially available from BASF). The use of these types of formulations may assist the overall cleaning process by partially reacting with oxides and other engine deposits to make them more susceptible to reacting with the cleaning components described herein applied during the contacting step. If a preparatory step is applied, the surface may then be rinsed to remove debris and/or chemical formulation prior to contacting the surface with the cleaning composition. Further, the chemical preparation step may be applied prior to disposing the turbine engine component in the cleaning apparatus 210 (i.e., external to the cleaning apparatus), or after disposing the turbine engine component in the cleaning apparatus 210 (i.e., internal to the cleaning apparatus).

In some embodiments, the disposing step further includes disposing a second portion (e.g., hub portion 110) of the turbine engine component (e.g., turbine disc 100) in a sheltered chamber 214 defined by an upper portion 211 and a lower portion 212 of the cleaning apparatus 210, which is shown in fig. 4A and 4B. As previously described in detail, the masking chamber 214 and the cleaning chamber 213 are fluidly sealed from each other via a sealing mechanism 230 (shown in fig. 4A and 4B) such that a surface of a second portion of the turbine engine component (e.g., the hub portion 110) does not substantially contact the cleaning component 10 during the cycling and contacting steps.

As previously mentioned, the design of the cleaning apparatus 210 described herein enables the application of the cleaning composition 10 to selected portions of turbine engine components, thereby allowing for localized targeted cleaning. Thus, in one embodiment, the contacting step includes contacting the cleaning composition 10 with a portion of the turbine engine component while leaving another portion of the turbine engine component substantially free of the cleaning composition. Examples of such embodiments include where the turbine engine component is or includes a disk turbine for an engine assembly. In this illustrative example, cleaning composition 10 may be applied to a dovetail-shaped portion of a disk (meaning to some or all of this portion) while leaving the remainder of the disk substantially free of the composition. In the above example, the first portion of the turbine engine disposed in the cleaning chamber 213 may include the dovetail region 122 of the turbine disk 100. And, the remaining hub portion 110 is a second portion disposed in the masking chamber 214. In such an example embodiment, the cleaning composition selectively contacts some or all of the dovetail region 122 of the turbine disk 100, and the remaining hub portion 110 does not substantially contact the cleaning composition.

Similarly, the dovetail portion of the turbine blade (again, some or all of the dovetail portion) may selectively contact the cleaning composition 10, while other areas of the blade do not contact the composition. In yet another example, track portions of the housing or frame may selectively contact the cleaning composition 10 while other areas of these members do not contact the composition. In the above examples, the first portion of the turbine engine disposed in the cleaning chamber 213 may include a dovetail portion of a turbine blade, or a rail portion of a turbine/compressor housing. And, the remaining portion is a second portion provided in the masking chamber 214.

Referring again to fig. 3-6, the method 1000 further includes, at step 1002, circulating a cleaning composition from the reservoir 250 to the cleaning chamber 113 via the manifold assembly 220 and the plurality of fill holes 201 disposed in the upper portion 211 of the cleaning apparatus 210. The cleaning composition can be circulated using a pipe or conduit (e.g., pipe 215) and a suitable control mechanism (e.g., valve). The method further includes, at step 1003, selectively contacting a cleaning component with a surface of a first portion of a turbine engine component.

The cleaning component selectively contacts the surface of the turbine engine component for a sufficient duration to allow at least partial removal of the oxide without unduly damaging the underlying metal. In some embodiments, the cleaning composition contacts the surface of the turbine engine component for a duration in a range from about 2 minutes to about 20 minutes. In certain embodiments, the cleaning composition contacts the surface of the turbine engine component for a duration in a range from about 4 minutes to about 8 minutes. The duration of contact can be controlled by controlling the duration of the circulation of the cleaning composition 10 through the cleaning chamber 113 of the cleaning apparatus 210. In some embodiments, the method includes controlling the duration for circulating the cleaning components through the cleaning chamber 213 via the manifold assembly 220 such that a desired amount of cleaning is achieved. In some embodiments, the duration of the circulation of the cleaning composition through the cleaning chamber 213 ranges from about 2 minutes to about 20 minutes. In certain embodiments, the duration of the circulation of the cleaning composition 10 through the cleaning chamber 213 ranges from about 4 minutes to about 8 minutes.

Typically, the method is performed at atmospheric pressure, but this is not essential. The method may be performed at any temperature. The choice of temperature for any particular case may depend in part on competing characteristics, such as the desire for rapid reaction/removal of oxides, for which higher temperatures may be desirable; and the desire to avoid significant reaction of the underlying metal of the article, for which lower temperatures may be desirable. In some embodiments, the contacting step is performed at ambient temperature (such as about 20 degrees celsius) or higher. In some embodiments, the contacting step is performed at a temperature of less than 60 degrees celsius. In certain embodiments, the contacting step is performed at a temperature in a range of about 20 degrees celsius to about 55 degrees celsius; and in a particular embodiment, ranges from about 20 degrees celsius to about 45 degrees celsius.

Referring again to fig. 3-6, the method 1000 further includes recirculating the cleaning composition 10 from the cleaning chamber 113 to the reservoir 250 via the manifold assembly 220 and the plurality of drain holes 202 disposed in the lower portion 212 of the cleaning apparatus 210 at step 1004. The cleaning composition can be recirculated using a tube or conduit (e.g., tube 216) and a suitable control mechanism (e.g., valve). The recycling and re-circulating steps of the methods described herein can allow for collection and re-use of cleaning components that do not occur in traditional cleaning methods (e.g., manual application or immersion) in an efficient manner. Further, the repeated use of the cleaning component can significantly reduce the amount of cleaning component required compared to standard immersion tasks for cleaning.

Further, depending on the chemistry of the cleaning component, in some embodiments, it may be desirable to circulate the cleaning component over the surface rather than allowing the cleaning component to stagnate. This may be particularly desirable for cleaning components that have strong reducing properties relative to the base metal. In such cases, corrosion (e.g., pitting) of the base metal may be avoided by not allowing the cleaning components to stagnate on the surfaces of the turbine engine components. In some embodiments, the cleaning fluid is circulated at a rate of about 0.1 liters/minute to about 5 liters/minute. In particular embodiments, the cleaning fluid is circulated at a rate of about 0.25 liters/minute to about 2 liters/minute.

The residual cleaning components are then removed from one or both of the surfaces of the turbine engine component and the cleaning chamber. Along with the cleaning component, other materials such as loose oxides, dust, other engine deposits, and any reaction products formed as a result of the reaction between the cleaning component and the oxide may also be removed. In some embodiments, the removing step may be accomplished by: rinsing the contact area with a solvent, such as water; by mechanically removing the components; by wiping; or via any other technique effective to remove the cleaning components from the surface. In embodiments involving mechanical removal of the cleaning components, the turbine engine component may be removed from the cleaning apparatus and then subjected to a removal step.

In certain embodiments, the cleaning component is removed from the surface and the cleaning chamber by employing a solvent (e.g., water) as the cleaning/rinsing component. In this case, after the cleaning composition is circulated through the cleaning chamber for the desired duration, the flow of cleaning composition from the manifold assembly may be stopped by closing the appropriate valve. Further, a valve in the manifold assembly for the cleaning composition may be opened, thereby circulating the cleaning composition from the cleaning reservoir to the cleaning chamber. As shown in fig. 5, the method further includes circulating the cleaning composition 20 through the manifold assembly 220 and a plurality of vents 203 disposed in the upper portion 211 of the cleaning device 210. Similar to the cleaning step, the method further includes recirculating the cleaning composition 20 from the cleaning chamber 213 to the cleaning reservoir 260 via the manifold assembly 220 and the plurality of drain holes 202 disposed in the lower portion 212 of the cleaning apparatus 210. Embodiments of the present disclosure may thus advantageously collect an effluent stream using a wash component. Thus, collection of hazardous waste is facilitated while human contact is minimized.

The cleaning component contacts the surface of the turbine engine component for a sufficient duration to allow the cleaning component to be at least partially removed from one or both of the surface of the turbine engine component and the cleaning chamber. In some embodiments, the duration of the circulation of the cleaning composition through the cleaning chamber ranges from about 2 minutes to about 20 minutes. In certain embodiments, the duration of the circulation of the cleaning composition through the cleaning chamber ranges from about 4 minutes to about 8 minutes. After removal of the cleaning components, the sequence of contacting and removing (with or without preparatory steps) may be repeated, for example in cases where the amount of oxide removed from the surface is considered insufficient.

In some embodiments, the cleaning component is designed to have a sufficiently high viscosity to avoid undesirable flux of the component during the cleaning process. In general, the components are formulated to have a composition of at least 10⁴Viscosity of poise to achieve this. The viscosity can be increased above this value, if this is done, it will enhance some aspects of the process. For example, a higher viscosity component may be desirable if the surface includes a bevel such that gravity increases the risk of undesirable flow. In some embodiments, the viscosity is less than or equal to 10⁶Poise; the upper limit of viscosity may be set in part by the system and process of applying the cleaning composition to the surfaceThe requirements of the program are specified. The viscosity values described herein typically represent values obtained under conditions of temperature and pressure present during the cleaning process.

The cleaning component is formulated to remove oxides from the surface of the turbine engine component while avoiding undesirable levels of reaction with the metal of the turbine engine component. The minimum amount of oxide to be removed may be specified for a given process, based at least in part on the purpose of the cleaning process. For example, where visual inspection of the underlying metal is required, a certain minimum area fraction of the oxide may be specified below which inspection of the underlying metal is deemed to be ineffective. In accordance with prior art parlance, the term "material loss" is used to denote the amount of underlying metal that is concomitantly removed during oxide removal. The amount of "material loss" that can be tolerated in a given process is dictated at least in part by the nature of the components and area being cleaned; for example, where the area to be cleaned is expected to experience high stresses in operation, less material loss may be tolerated to avoid excessive weakening of the components. Furthermore, in addition to or instead of defining a certain upper limit for material loss, a given process may dictate a certain quality of the surface after cleaning. For example, where the process may specify a thickness threshold for material loss, such as 25 microinches (about 0.6 microns), it may further specify the existence, number, and/or limits of depth of tolerable erosion points, the extent to which intergranular corrosion is permitted, and/or other boundary conditions.

Given the competing constraints of reactivity with the oxide and non-reactivity with the underlying metal, the cleaning components are formulated to be selectively reactive with the oxide. As used herein, the term "selective reactivity" means that for a given process, the component exhibits acceptable reactivity with the oxide while meeting process specifications for material loss and other attack of the metal. Those skilled in the art will appreciate that acceptable reactivity with oxides and acceptable non-reactivity with metals can be readily determined for a given combination of process conditions and metal components.

In some embodiments, the cleaning component includes an acid, an active compound, and a thickener. The appropriate combination of acid and active compound provides the required choice of cleaning component with respect to the oxide. In some embodiments, the acid comprises a mineral acid, such as nitric acid, phosphoric acid, sulfuric acid, hydrochloric acid, acetic acid, or a combination thereof.

As used herein, the term "active compound" refers to a compound, such as a salt, that provides a chemical moiety to a cleaning component that participates in the removal of oxides. In some embodiments, the compound comprises a halide, such as a chloride. In certain embodiments, the active compound comprises an iron salt. In certain embodiments, the reactive compound comprises ferric chloride, which provides attractive properties to cleaning components applied to oxidized nickel-based superalloy components. The selection of an appropriate active compound and its concentration in the cleaning component will depend, at least in part, on the processing conditions and the nature of the metal and oxide.

The cleaning composition may further comprise water to form an aqueous solution. The combination of acid, active compound and remaining water may form an acidic matrix. In some embodiments, the total amount of acid in the cleaning component ranges from about 150 grams/liter to about 850 grams/liter. In certain embodiments, the total amount of acid in the cleaning component ranges from about 200 grams/liter to about 800 grams/liter. In some embodiments, the total amount of active compound in the cleansing component ranges from about 10 grams/liter to about 200 grams/liter. In certain embodiments, the total amount of active compound in the cleansing component ranges from about 20 grams/liter to about 90 grams/liter. The remainder may be made up of water (e.g., distilled water).

To achieve the desired viscosity levels described previously, the cleansing component further includes a thickening agent. As used herein, the term "thickener" means that an additive that imparts a high viscosity is present in the cleaning component relative to a component lacking such an additive. In some embodiments, the thickener is dissolved in an acidic matrix, creating a gel by promoting, for example, a three-dimensional network of cross-linked material within a liquid matrix. In other embodiments, the thickener is a particulate material that will be suspended within an acidic matrix to form a paste. The thickening agent is present in the cleansing component in an amount effective to produce a desired level of viscosityPerforming the following steps; the viscosity of the cleaning components described herein is generally at least 10 as previously mentioned⁴Poise.

Inorganic compounds that are substantially inert with respect to the acidic matrix, such as, for example, a plurality of oxide particles, provide one example of a thickening agent that can be suspended to form a cleaning component. In some embodiments, the thickener comprises a plurality of oxide particles comprising silica, titania, or a combination thereof. Examples of suitable oxide particles are fumed silica, fumed titanium dioxide, or a combination thereof. Thickening behavior depends in part on the size and amount of particles suspended within the matrix. Typically, although not necessarily, the nominal size (i.e., median size) of the particulate component ranges from about 0.005 micron to about 0.5 micron. In some embodiments, the nominal particle component size ranges from about 0.005 microns to about 0.3 microns, and in particular embodiments, this range is from about 0.007 microns to about 0.2 microns. With respect to the amount of particles present, as mentioned above, the amount can be adjusted to provide a desired viscosity level for a given application. In some embodiments, the thickening agent is present in the cleansing component at a concentration of at least about 0.5% by weight of the cleansing component. In some embodiments, the concentration is up to about 5% by weight of the cleaning component. In some embodiments, the thickening agent is present in the cleansing component at a concentration ranging from about 1% to about 5% by weight of the cleansing component. In some embodiments, the thickening agent is present in the cleansing component at a concentration ranging from about 1% to about 2% by weight of the cleansing component.

In certain embodiments, the cleaning component includes hydrochloric acid, ferric chloride, and fumed silica. In some such cases, the cleaning composition includes about 10 g/l to about 20 g/l fumed silica, 50 g/l to about 100 g/l ferric chloride, 170 g/l to about 200 g/l hydrochloric acid, and the balance water. In certain embodiments, the cleaning component includes nitric acid, sulfuric acid, hydrochloric acid, acetic acid, ferric chloride, and fumed silica. In some such cases, the cleaning component includes about 10 g/l to about 20 g/l fumed silica, 20 g/l to about 40 g/l ferric chloride, 750 g/l to about 800 g/l total acid, and the balance water. In certain embodiments, cleaning components suitable for the methods and systems described herein are disclosed in co-pending U.S. patent application publication 2016/0024438, the disclosure of which is incorporated herein by reference.

As previously mentioned, conventional cleaning methods for cleaning turbine engine components (e.g., turbine disks prior to crack inspection) may require multiple cleaning steps before the surfaces are effectively cleaned. For example, some conventional cleaning methods may involve applying a 4-step cleaning cycle involving: an alkaline component, a first acidic component, an alkali metal permanganate component, and a second acidic component. The steps involving the alkali metal permanganate solution and the second acidic component may need to be repeated multiple times (e.g., at least 20 times) before cleaning can be achieved due to the presence of recalcitrant oxides on the surface. This can result in time consuming and cost inefficient cleaning cycles.

Further, conventional cleaning methods may employ liquid cleaning components that may be undesirable where the area of contact of the cleaning components needs to be limited. For example, some components include multiple materials, wherein one or more materials are incompatible with the cleaning component. As another example, in some components, deposits tend to form only at certain locations, while other locations on the component remain acceptably free of deposits. In some cases, such as where it is desirable to selectively expose only regions of a component to a cleaning composition, conventional cleaning methods using liquid cleaning compositions may require additional steps, such as component disassembly, masking processes, or other techniques with reapplication of dimensional building materials and the addition of time and expense to the overall cleaning process.

Some embodiments of the present disclosure further address the noted shortcomings in conventional cleaning methods by employing cleaning components having high viscosities relative to conventional liquid cleaning components. The viscous component substantially remains in the area of the component on which the viscous component is disposed during the cleaning process, thereby providing the ability to clean selected areas of the turbine engine component without over-exposing adjacent areas where exposure to the cleaning component is undesirable or incompatible with the component material.

In some embodiments, a method for selectively cleaning surfaces of turbine engine components using a viscous cleaning composition is provided. The method is described with reference to fig. 7. As shown in FIG. 7, method 2000 includes, at step 2001, applying a cleaning cycle to a surface of a turbine engine component. Step 2001 of applying the cleaning cycle includes the steps of sequentially contacting the surface of the turbine engine component with an alkaline component, a first acidic component, a first alkali permanganate component, and a second acidic component. In some embodiments, step 2001 of applying a cleaning cycle is similar to a 4-step conventional cleaning cycle applied to clean turbine engine components prior to inspection. Non-limiting examples of the basic component include Ardrox185L, non-limiting examples of the first acidic component include Ardrox1873, non-limiting examples of the first alkali metal permanganate component include Ardrox1435, and non-limiting examples of the second acidic component include Ardrox 1218. As previously mentioned, Ardrox is the trade name of a component available from BASF. In some embodiments, method 2000 may further include one or more preparatory steps for preparing the surface of the turbine engine component prior to step 2001, which is described in detail previously.

The cleaning cycle may be applied to the surface of the turbine engine component or only a portion thereof. In some embodiments, the cleaning cycle may be applied to a surface of a turbine engine component. For example, where the turbine engine component is a turbine disk 100 (shown in fig. 1), the step 2001 of applying the cleaning cycle may be implemented on both portions 110 and 120 of the disk. The application of the 4-step cleaning cycle may allow for the recovery of parent metal on the surface of the turbine engine component. However, as previously mentioned, certain portions of the turbine engine component may include complex oxides of one or more metals. The cleaning cycle may be inefficient such that these oxides cannot be removed from the surface efficiently without the use of an abrasive cleaning method or the repetition of a large number of cleaning cycles.

Accordingly, the method further includes, at step 2002, selectively contacting a first portion of a surface of the turbine engine component with a second alkali permanganate component. In some embodiments, the second alkali permanganate solution may be the same as the first alkali permanganate composition used in step 2001. In some embodiments, the second alkali permanganate solution may be different from the first alkali permanganate composition used in step 2001. The second alkali permanganate solution may further oxidize the surface of the first portion of the turbine engine component.

The method 2000 further includes, at step 2003, selectively contacting a first portion of a surface of a turbine engine component having at least 10⁴Poise viscosity of the cleaning component. As previously mentioned herein, by employing a viscous cleaning component, selective cleaning of turbine engine components may be performed efficiently and effectively. Steps (II) and (III) are accomplished such that the remaining second portion of the surface of the turbine engine component is not substantially in contact with the alkali permanganate component and the cleaning component.

The step 2002/2003 of selectively contacting the surface of the turbine engine component may be accomplished using any technique known in the art for applying a composition to a surface. Examples of such techniques include brushing, rubbing or squeezing the composition onto a surface. As previously mentioned, the viscous nature of the cleaning component enables the component to be applied to selected portions of an article, thereby allowing for locally targeted cleaning. In certain embodiments, steps (II) and (III) may be implemented using the systems and methods described previously herein with reference to fig. 1-6.

The cleaning component allows for at least partial removal of oxides from selected surfaces of the turbine engine component. In certain embodiments, the cleansing component comprises a third acidic component, an active compound, and a thickening agent. Non-limiting examples of suitable acids in the third acidic component include inorganic acids such as nitric acid, phosphoric acid, sulfuric acid, hydrochloric acid, acetic acid, or combinations thereof. Non-limiting examples of suitable active compounds include ferric chloride. Non-limiting examples of suitable thickeners include fumed silica, fumed titanium dioxide, or combinations thereof. The compositional characteristics of the cleaning components are described in detail previously.

The cleaning component selectively contacts the surface of the turbine engine component for a sufficient duration to allow at least partial removal of the oxide without unduly damaging the underlying metal. In some embodiments, the cleaning composition contacts the surface of the turbine engine component for a duration in a range from about 2 minutes to about 20 minutes. In certain embodiments, the cleaning composition contacts the surface of the turbine engine component for a duration in a range from about 4 minutes to about 8 minutes.

The residual cleaning component is then removed from the surface of the turbine engine component using one or more of the techniques previously described in detail. After removal of the cleaning component, the sequence of applying, contacting and removing (with or without preparatory steps) is repeated, for example in cases where the amount of oxide removed from the surface is considered insufficient. In some embodiments, after step 2003, the sequence of steps 2001, 2002, and 2003 may be repeated n times, where n is 1 to 3. In certain embodiments, the methods and techniques described herein are effective to remove a sufficient amount of oxide without the need to repeat steps 2001, 2002, and 2003.

In some embodiments, the method may further include the step of inspecting the surface of the turbine engine component for cracks (not shown in the figures). Any suitable technique for crack inspection may be employed. In certain embodiments, the methods and techniques described herein may be particularly suitable for cleaning the surface of a turbine engine component prior to crack inspection using Fluorescent Penetrant Inspection (FPI).

Examples of the invention

The following examples are provided to further illustrate non-limiting embodiments of the present disclosure.

Turbine disks that have been previously exposed to high temperatures exhibit oxide formation in their dovetail portions. The disk includes a nickel-based superalloy. The disks were subjected to a single standard 4-step cleaning cycle to recover the parent metal of the disks for a detailed visual inspection. The 4-step cleaning cycle includes the sequential application of Ardrox185L, Ardrox1873, Ardrox1218, and Ardrox1435 (commercially available from BASF). The tray further undergoes a rinsing step in between. After applying the 4-step cleaning cycle, the dovetail portion of the turbine disk was contacted with an alkali metal permanganate solution (Ardrox188) using a conventional immersion tank to oxidize the dovetail surface for 30-60 minutes (according to the manufacturer's guidelines).

After the step of applying the alkali metal permanganate solution, the turbine disk is rinsed and then set in a clamshell cleaning device (e.g., the cleaning device shown in fig. 3-5). Using the systems and methods described herein, viscous cleaning compositions according to embodiments described herein are applied to oxide deposits on dovetail shaped regions. The viscous cleaning component comprises about 180-200 g/l hydrochloric acid, about 50-100 g/l ferric chloride, about 18.75-21 g/l fumed silica (nominal size 0.2 microns), and the balance water. The cleaning composition was circulated through the cleaning chamber at a rate of approximately 1 liter/minute for 6 minutes using a manifold system. The cleaning components are recycled and reused, limiting the total cleaning component amount to less than 2 liters, whereas a standard immersion tank requires 6000 liters. All of the dove-tail posts in the tray are subjected to the contacting and cleaning steps simultaneously, thereby reducing the cleaning time to less than 1 production shift, whereas standard immersion cleaning techniques require one week. After circulating the cleaning composition for 6 minutes, the cleaning composition was removed from the blades by rinsing the cleaning chamber with water. The disc cleaning effectiveness and the ease of FPI inspection were then checked. It was observed that most of the oxide deposit was removed from the disk dovetail post, and the disk was capable of being FPI inspected. Damage to the metal underneath the blade is minimal.

The appended claims are intended to claim the invention as broadly as it is conceived and the examples provided herein illustrate selected embodiments from the manifold of all possible embodiments. Accordingly, it is applicants' intention that the appended claims are not to be limited by the choice of examples utilized to illustrate features of the present invention. As used in the claims, the word "comprise" and its grammatical variants also logically encompasses and includes variations and different degrees of phrases such as, for example, but not limited to, "consisting essentially of" and "including". Where desired, ranges are provided; those ranges are inclusive of all subranges therebetween. It is expected that variations in these ranges will occur to practitioners having ordinary skill in the art and, where not already dedicated to the public, those variations would, where feasible, be considered to be covered by the appended claims. It is also expected that advances in science and technology will enable equivalents and alternatives to be obtained which are now unforeseen due to inaccuracies in language and which, where feasible, will also be considered to be covered by the following claims.