Conformal coating mask and system for components

Abstract

The invention is titled Conformal Coating Mask and System for a Component. The invention provides a conformal coating mask (300) for use with a turbine component having a plurality of cooling holes (201). The conformal coating mask (300) includes at least two anchors (301, 310); a plurality of radial mask strips (303) integrally formed with each of the at least two anchors (301, 310) and extending between the at least two anchors (301, 310); and at least one coating mask fixation insert (330). Each coating mask fixation insert of the at least one coating mask fixation insert (330) is integrally formed with a respective at least one radial mask strip (303); wherein the plurality of radial mask strips (303) align with and cover the plurality of cooling holes (201).

Description

BACKGROUND

[0001] The present disclosure relates generally to systems including a coating mask formed simultaneously with a component. In particular, the present disclosure relates to systems including a conformal coating mask formed simultaneously with a turbine blade component through additive manufacturing. SUMMARY

[0002] A first aspect of the present disclosure provides a conformal coating mask for use with a turbine component having a plurality of cooling holes. The conformal coating mask includes at least two anchors; a plurality of radial mask strips integrally formed with each of the at least two anchors and extending between the at least two anchors; and at least one coating. Each of the at least one coating mask securing inserts is integrally formed with a respective at least one radial mask strip; wherein the plurality of radial mask strips are aligned with and cover the plurality of cooling holes.

[0003] A second aspect of the present disclosure provides a system including a turbine component and a conformal coating mask formed simultaneously with the component. The turbine component includes an airfoil and a plurality of cooling holes therein. The conformal coating mask includes: at least two anchors; a plurality of radial mask strips integrally formed with each of the at least two anchors and extending between the at least two anchors; and at least one coating mask securing insert. Each of the at least one coating mask securing inserts is integrally formed with a respective at least one radial mask strip; wherein the plurality of radial mask strips are aligned with and cover the plurality of cooling holes.

[0004] Exemplary aspects of the present disclosure are designed to address the problems described herein and / or other problems that can not be discussed. BRIEF DESCRIPTION OF DRAWINGS

[0005] These and other features of the present disclosure will be more readily understood from the following detailed description of the various aspects of the present disclosure, taken in conjunction with the accompanying drawings that illustrate various embodiments of the present disclosure, in which:

[0006] Figure 1 A schematic perspective view of a blade with a conformal coating mask according to embodiments of the present disclosure is shown;

[0007] Figure 2 A cross-sectional view of a blade with a conformal coating mask according to embodiments of the present disclosure taken along line 2-2 of Figure 1

[0008] Figure 3 A side cross-sectional view of a coating mask securing insert in a blade cooling hole according to embodiments of the present disclosure is shown;

[0009] Figure 4 ​A side cross-sectional view of a coating mask fixation insert is shown in accordance with embodiments of the present disclosure;

[0010] Figure 5 A side cross-sectional view of a coating mask fixation insert is shown in accordance with embodiments of the present disclosure;

[0011] Figure 6 A top perspective view of a coating mask fixation insert is shown in accordance with embodiments of the present disclosure taken along line 6-6 in Figure 4

[0012] Figure 7 A top perspective view of a coating mask fixation insert is shown in accordance with embodiments of the present disclosure taken along line 6-6 in Figure 4

[0013] Figure 8 A bottom perspective view of a coating mask fixation insert is shown in accordance with embodiments of the present disclosure;

[0014] Figure 9 A bottom perspective view of a coating mask fixation insert is shown in accordance with embodiments of the present disclosure;

[0015] Figure 10 Another aspect of a coating mask fixation insert for cooling holes is shown in accordance with embodiments of the present disclosure; and

[0016] Figure 11 Yet another aspect of a coating mask fixation insert is shown in accordance with embodiments of the present disclosure.

[0017] It should be noted that the figures of the present disclosure are not necessarily drawn to scale. The figures are intended to depict only typical aspects of the present disclosure, and therefore should not be considered as limiting the scope of the present disclosure. In the drawings, like numbering represents similar elements between the figures. DETAILED DESCRIPTION

[0018] ​​First, in order to clearly describe the current technology, when referring to and describing conformal coating mask systems formed concurrently with turbine blades or other turbine components having cooling holes (hereinafter referred to as "turbine blades" or "blades" for ease of reference) by additive manufacturing, it is necessary to select specific terminology. These conformal coating mask systems provide cooling hole protection for the turbine blades during any post-turbine blade formation processing, such as but not limited to coating. To the extent possible, general industry terminology will be used and employed in a manner consistent with the accepted meanings of the terms. Unless otherwise indicated, such terms should be given a broad reading consistent with the context of the present application and the scope of the appended claims. Those of ordinary skill in the art will appreciate that several different or overlapping terms can be used to reference a particular component. An object that can be described herein as a single part can include multiple components and be referenced elsewhere as being composed of multiple components. Alternatively, an object that can be described herein as including multiple components can be referred to elsewhere as a single part.

[0019] Furthermore, several descriptive terms can be used regularly herein, and it can prove helpful to define those terms at the outset of this section. Unless otherwise indicated, these terms, and their definitions, are as follows. As used herein, "downstream" and "upstream" are terms indicating direction with respect to the direction of fluid flow, such as working fluid through a turbine engine, or for example, air flow through a combustor or coolant through one of the component systems of a turbomachine. The term "downstream" corresponds to the direction of fluid flow, and the term "upstream" refers to the direction opposite to the flow. Without any further particularity, the terms "forward" and "aft" refer to direction, with "forward" referring to the forward or compressor end of the engine, and "aft" referring to the aft or turbomachine end of the engine.

[0020] It is often necessary to describe parts that are disposed at different radial positions relative to a central axis. The term "radial" refers to movement or position that is perpendicular to the axis. For example, if a first component resides closer to the axis than a second component, it will be stated herein that the first component is "radially inward" of or "inboard" of the second component. On the other hand, if the first component resides further from the axis than the second component, it can be stated herein that the first component is "radially outward" or "outboard" of the second component. The term "axial" refers to movement or position that is parallel to the axis. Finally, the term "circumferential" refers to movement or position that is around the axis. It will be appreciated that such terms can be applied with respect to the central axis of the turbine.

[0021] Furthermore, several descriptive terms can be used regularly herein, as follows. The terms "first," "second," and "third" can be used interchangeably to distinguish one component from another and are not intended to convey a position or importance of the individual components.

[0022] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present disclosure. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. "Optional" or "optionally" mean that the subsequently described event or circumstance can or can not occur, and that the description includes instances where the event occurs and instances where it does not.

[0023] In the case of elements or layers being referred to as "on", "engaged to", "connected to", or "coupled to" another element or layer, it can be directly on, engaged, connected, or coupled to the other element or layer, or one or more intervening elements or layers can be present. In contrast, when an element is referred to as being "directly on", "directly engaged to", "directly connected to", or "directly coupled to" another element or layer, there are no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., "between" versus "directly between", "adjacent" versus "directly adjacent", etc.). As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0024] To facilitate understanding of embodiments of the present disclosure, the rate of change and improvement in the fields of power generation, aviation, and other fields is accompanied by extensive research into the manufacture of components used in these fields. Conventional manufacturing of metal, plastic, or ceramic composite components generally includes first milling or cutting away areas from a sheet of material, and then processing and modifying the cut material to produce a part, which can be simulated using a computer model in, for example, a drafting software. Manufactured components that can be formed from metal can include, for example, airfoil components for installation in a turbomachine, such as an aircraft engine or a power generation system.

[0025] Additive manufacturing (AM) includes a variety of processes that produce components through the successive layering of material rather than the removal of material. Additive manufacturing can thus form complex geometries without the need for any kind of tooling, molds, or fixtures, and with little or no waste of material. Rather than machining a component from a solid material blank, much of which is cut away and discarded, the only material used in additive manufacturing is that which is needed to shape the component.

[0026] Additive manufacturing techniques generally include the use of a three-dimensional computer aided design (CAD) file of the part to be formed to electronically slice the part into layers (e.g., 18 microns to 102 microns thick) and create a file with a two-dimensional image (including vectors, images, or coordinates) of each layer. The file can then be loaded into a preparation software system that interprets the file so that the part can be built by different types of additive manufacturing systems. In the 3D printing, rapid prototyping (RP), and direct digital manufacturing (DDM) forms of additive manufacturing, layers of material are selectively deposited, sintered, formed, fused, etc. to form the part.

[0027] In metal powder additive manufacturing techniques such as direct metal laser melting (DMLM), also known as selective laser melting (SLM), layers of metal powder are sequentially fused together to form the part. More specifically, layers of fine metal powder are sequentially fused after being uniformly distributed over a metal powder bed using an applicator. Each applicator includes an applicator element in the form of a die lip, brush, doctor blade, or roller made of metal, plastic, ceramic, carbon fiber, or rubber that uniformly spreads the metal powder over the build platform. The metal powder bed can be moved in a vertical axis. The process occurs in a process chamber with a precisely controlled atmosphere. Once each layer is formed, each two-dimensional slice of the part geometry can be fused by selectively fusing the metal powder. The fusing can be performed by a high-powered fusing beam, such as a 100 watt ytterbium laser, in order to completely weld (fuse) the metal powder to form solid metal. The fusing beam is moved in the X-Y directions using a scanning mirror and is of sufficient intensity to completely weld (fuse) the metal powder to form solid metal. The metal powder bed can be lowered for each subsequent two-dimensional layer and the process is repeated until the part is completely formed.

[0028] Further, turbine components such as, but not limited to, airfoils, turbine blades, and vanes (nozzles) of gas turbine engines generally require complex cooling schemes in which cooling air flows through the airfoil and is then exhausted through carefully structured cooling holes. For example, and by way of illustration only of the present disclosure, the cooling holes of a component can include cooling holes at a trailing edge of the airfoil. Turbine blade performance is related to the ability to provide uniform cooling of the airfoil surface. Thus, control of the cooling hole size and shape is important in turbine airfoil design, as the size and shape of the openings can determine the flow rate out of a given hole, the hole distribution across the airfoil, and the overall flow rate distribution within the cooling circuit. Other factors, such as backflow allowance, are also affected by changes in opening size. Thus, preserving the intended configuration of the cooling holes, including after post-component processing such as coating, will enable the cooling holes to perform their intended function.

[0029] In addition to conventional drilling techniques such as laser machining and electrical discharge machining (EDM), complex advanced casting practices can be used to produce airfoils with dimensionally correct cooling hole openings so that opening size can be repeatably controlled. Once cast, a follow-on airfoil manufacturing operation must be performed so that the casting to a certain size cooling hole opening is not addressed by an operation that changes the size of some or all of the cooling hole openings.

[0030] However, as air through some turbines has become increasingly complex, additive manufacturing processes (as discussed above) have been employed to form turbine components. Additive manufacturing processes enable the formation of intricate, serpentine, and complex cooling passages and cooling hole openings in a manner that is easier, more efficient, and less costly than some traditional formation methods.

[0031] Regardless of formation, as the operating environment of turbine components has become increasingly severe, protective coatings are often applied to these turbine components both at the time of manufacture of the turbine components and possibly during service. Modern high-efficiency combustion turbines have firing temperatures in excess of about 1,000 degrees Celsius, and as the demand for more efficient engines continues, even higher firing temperatures are expected. Many components forming the "hot gas path" combustor and turbine sections are directly exposed to erosive hot combustion gases, such as combustor liners, transition ducts between the combustion and turbine sections, and turbine stationary vanes and rotating blades and surrounding ring sections. In addition to thermal stresses, these and other components are also exposed to mechanical stresses and loads, causing further wear to the components.

[0032] By coating the components with protective coatings, many of the iron-, cobalt-, and nickel-based superalloy materials traditionally used to manufacture most of the combustion turbine components used in the hot gas path sections of combustion turbine engines are isolated from the hot gas stream in order to withstand long-term operation in this erosive high-temperature combustion environment. Protective coatings include, but are not limited to, thermal barrier coatings (TBCs), bond coats, environmental barrier coatings (EBCs), combinations thereof, and other coatings now known or hereafter developed. Protective coatings can be prepared through a multi-step process that includes coating the surfaces requiring protective coatings with, for example, bond coats and subsequent additional coatings according to the intended use of the turbine component and the environment associated with that use.

[0033] TBCs are highly advanced material systems. These coatings are used as protective coatings to isolate components from large and long-duration thermal loads by utilizing thermal insulating materials that can maintain a measurable temperature differential between the load-bearing alloy and the coating surface. Doing so can allow these coatings to have higher operating temperatures while limiting the thermal exposure of the structural components, thereby extending component life by reducing oxidation and thermal fatigue.

[0034] TBCs are applied to turbine components by various methods. Spray coating is commonly used to apply TBCs (or other coatings). Exemplary spray coating processes include, but are not limited to, plasma spraying in both air and vacuum, cold spraying, electrostatic spraying, electron beam physical vapor deposition, chemical vapor deposition, thermal spraying, high velocity oxygen-fuel coating, physical vapor deposition, combinations thereof, and other spray coating techniques now known or hereafter developed.

[0035] Reference is made to Figure 1 Turbine blade 100 includes an airfoil 105 and a base 116. Base 116 includes a platform 104 to which airfoil 105 is attached. Airfoil 105 has a tip end 108 with a recess 122 defined therein. Airfoil 105 also includes a leading edge 110 and a trailing edge 111.

[0036] As noted above, cooling holes are commonly required in gas turbine engine components. Cooling holes often require complex cooling schemes in which cooling air is flowed through an airfoil and then exhausted through carefully configured cooling holes. In Figure 1 and Figure 2 In, the complex cooling scheme includes cooling passages 128 Figure 2 that open into tip end cooling holes 201 in tip end 108. The complex cooling scheme also includes airfoil cooling holes 200 Figure 2 that are connected to cooling passages 128 by connecting tubes 129. Cooling holes 200 are typically provided in a column from platform 104 to tip end 108 on airfoil 105, in alignment with cooling passages 128.

[0037] One aspect of spray coating a turbine component (such as blade 100) according to embodiments of the present disclosure revolves around control of, or lack of control of, the spray around cooling holes 200, 201 of blade 100. Control of the spray here means that the spray avoids sanding up around cooling holes 200, 201 and the subsequent rework requirements. Of course, any coating or other post-processing / forming component treatment must not interfere with the airfoil meeting operational requirements, including cooling air flow requirements through the airfoil and exhaust through cooling holes at the airfoil surface.

[0038] "Sanding up" is a post-processing / forming coating result that should be avoided, which is the build-up of coating between the coated surface and the edges of the coating mask, thereby clogging the gap. The coating mask is intended to keep the coating out of the cooling holes, and excessive sanding up prevents the mask from being easily removed from the coated component. The coating mask must be spaced far enough from the surface to prevent sanding up, but yet must be close enough to the surface to keep the coating material away from the cooling holes. Of course, sanding up should be controlled in order to maintain the intended functionality of the cooling holes.

[0039] As will be discussed in detail below, sand clogging is due to the "shadowing" effect of the spray (e.g., TBC, but it is not intended to limit the embodiments) as it is deposited on the component (here, the vane 100). The shadowing effect can be best visualized by placing an object in front of a light source and observing the shadow cast by the object. The light rays that surround the object represent the deposited spray, while the shadow cast by the object represents the voids in the deposited spray. However, in a natural process called shadowing, holes that are too small or too close to each other (such as the cooling holes 200, 201) can create sand clogging, as the coating can "sand up" the holes by itself. At these holes, the coating can clog the holes. In addition, the coating material can not adhere or stick to the component or substrate strictly. Therefore, rework will be needed to clear the "sand up" holes 200, 201 (when the coating is built up over the target area and holes) or re-coat at locations where the coating does not adhere or stick to the component or substrate strictly, which can extend the processing time, require additional resources, and can cause opportunity cost losses, etc.

[0040] As embodied in the present disclosure, a conformal coating mask is provided to be formed simultaneously with a turbine component (e.g., the vane 100) to mitigate and in some cases avoid sand clogging and other undesirable effects caused by post-processing, such as but not limited to coating. As Figure 1 and Figure 2 As shown, the conformal coating mask 300 is formed simultaneously with the vane 100 by additive manufacturing. Thus, the conformal coating mask 300 can conform its configuration to the shape, profile, and tolerances of the vane 100. As shown, the conformal coating mask 300 wraps around and encircles at least a portion of the vane 100, and aligns with the profile of the airfoil 105 encircled by the conformal coating mask 300.

[0041] The conformal coating mask 300 includes self-biasing anchors 301, 302. The anchors 301, 302 are preferably positioned near the tip 108 and platform 104 of the vane 100. The anchors 301, 302 are formed flexibly for wrapping around and encircling the airfoil 105. The anchors 301, 302 are formed with end portions 320 and 321, which can be located at various positions around the airfoil 105. The anchors 301, 302 can start from the end portions 320, 321 at any position on the airfoil 105, and extend around the airfoil 105 to the other end portion 320, 321. The anchors 301, 302 can be formed with a plurality of layers of material, such as but not limited to a plurality of layers of a polymer material, a plurality of layers of a ceramic material, or a combination thereof. Figure 1In particular, the end portion 320 is located at the trailing edge 111 at which the initial coating mask fixing insert 330 is configured to be inserted into the corresponding cooling hole 200 (as described herein). The anchors 301, 302 can be wrapped around and encircle the airfoil 105 such that the end portion 321 terminates on the airfoil 105, typically to a point at which the anchors 301, 302 almost completely encircle the airfoil 105. The end coating mask fixing insert 330 is configured to be inserted into the corresponding cooling hole 200 (as also described below) to secure the end plug cover 331 to the airfoil 105.

[0042] The anchors 301, 302 can include a hinge structure 308 formed by additive manufacturing. Figure 2 The hinge structure 308 enables and facilitates the installation of the conformal coating mask 300 on the blade 100. The hinge structure 308 enables the anchors 301, 302 to be positioned around regions of the blade 100 that have curved sections and other complex surface profiles.

[0043] Further, desirably but not necessarily, the anchors 301, 302 extend around the airfoil 105 to correspond to regions of the airfoil 105 that have cooling holes 200 positioned therein. Accordingly, as described below, the conformal coating mask 300 includes a radial mask strip 303 having coating mask fixing inserts 330. The radial mask strip 303 extends between the anchors 301, 302 and extends the overall height of the airfoil 105. As described herein, the formation of the anchors 301, 302 and the radial mask strip 303 in alignment with the wing cooling holes 200 during additive manufacturing will position the coating mask fixing inserts 330 in alignment with the cooling holes 200 to mask those cooling holes 200.

[0044] The radial mask strip 303 is generally aligned with the column of cooling holes 200 and includes at least one coating mask fixing insert 330, and preferably a plurality of coating mask fixing inserts 330. The coating mask fixing inserts 330 are simultaneously additive manufactured with the plug strip 303 and the anchors 301, 302. Accordingly, as described herein, the coating mask fixing inserts 330 are in alignment with the cooling holes 200.

[0045] As Figure 1 and Figure 3As shown, the coating mask securing insert 330 on the radial mask strip 303 is configured to align with the cooling hole 200 on the airfoil 205. In one non-limiting aspect of the disclosure, all cooling holes 200 have a corresponding coating mask securing insert 330. Other non-limiting aspects of the disclosure include a coating mask securing insert 330 on the radial mask strip 303 for only one cooling hole 200 in a row (radial mask strip 306) on the airfoil 205; a coating mask securing insert 330 on the radial mask strip 303 for multiple cooling holes 200 in a row (radial mask strip 305); or a coating mask securing insert 330 on the radial mask strip 303 for each cooling hole 200 in a row (radial mask strip 304).

[0046] The radial mask strip 303 is configured to extend the entire length of the airfoil 105, from the tip 108 to the platform 104. Alternatively, the radial mask strip 303 is configured to extend a portion of the entire length of the airfoil 105, such as from the tip 108 but terminating before the platform 104, starting from a lower portion of the tip 108 and terminating at the platform 104, or starting from a lower portion of the tip 108 and terminating before the platform 104.

[0047] The coating mask securing insert 330 is integrally formed with each radial mask strip 303 during additive manufacturing and is configured to cover and correspond to the cooling hole 200. The coating mask securing insert 330 helps to align and secure the radial mask strip 303 in place. Aligning and securing the radial mask strip 303 in the cooling hole 200 by the coating mask securing insert 330 can be achieved by an insertion component 350 of the at least one coating mask securing insert 330 of each radial mask strip 303 into the cooling hole 200.

[0048] In certain instances, the insertion component 350 is configured to simply fit within the cooling hole 200 to align and secure the radial mask strip 303 in place. In other embodiments of the application, the insertion component 350 is configured to fit within the cooling hole 200 to frictionally engage a portion of the cooling hole 200 to align and secure the radial mask strip 303 in place.

[0049] In non-limiting aspects of the embodiments, as Figure 3As shown, the insertion component 350 of the radial mask strip 303 is formed with a compressible portion 332 configured to be disposed within the cooling hole 200, 201 when the blade 100 is masked using the conformal coating mask 300. The simultaneous additive manufacturing of the conformal coating mask 300 and the blade 100 allows the conformal coating mask 300 to conform to and match the surface 106 of the blade 100. However, the additive manufactured element, here the blade 100, includes unique contours and tolerances, and the conformal coating mask 300 configured to conform to the blade 100 allows the coating mask securing insert 330 to be in the desired alignment with the cooling holes 200, 201 on the airfoil 105.

[0050] The coating mask securing insert 330 includes a plug cap 331 Figure 3 ). The plug cap 331 has a convex top portion and is complementary in peripheral configuration to the corresponding cooling hole 200 that is additive manufactured for masking. The peripheral configuration of the plug cap 331 can be an elliptical peripheral Figure 6 ), a circular peripheral Figure 7 , or any other cooling hole complementary peripheral configuration now known or hereafter developed. Regardless of the shape of the plug cap 331 peripheral, the peripheral of the plug cap 331 is configured to extend over the entirety of each corresponding cooling hole 200, each coating mask securing insert 330 is aligned with and positionable on each corresponding cooling hole 200. The elliptical peripheral Figure 6 is configured for use with cooling holes 200 at particularly curved surface portions of the airfoil 105, such as but not limited to the leading edge 110 and the trailing edge 111. The circular peripheral Figure 7 is configured for use with cooling holes 200 positioned at intermediate locations on the airfoil 105. Further, embodiments of the present disclosure are intended to include any configuration of the plug cap 331 that covers over the cooling hole.

[0051] The compressible portion 332 of the coating mask securing insert 330 is formed on the bottom surface 339 of the coating mask securing insert 330. The compressible portion 332 enables the insertion and installation of the coating mask securing insert 330 into the cooling hole 200. The compressible portion 332 of the coating mask securing insert 330 is sufficiently resilient to be compressed as the coating mask securing insert 330 enters the cooling hole 200. The compressible portion 332 contacts the wall of the cooling hole 200, thereby compressing the compressible portion 332. Thereafter, the compressible portion 332 will frictionally secure the coating mask securing insert 330 in the cooling hole 200.

[0052] The compressible portion 332 of the coating mask securing insert 330 includes two compressible legs 333, 334 (for ease of description, the compressible legs 333, 334 will be referred to as "legs 333, 334"). The legs 333, 334 are integrally formed with the plug cover 331, the radial mask strip 303, and the conformal coating mask 300 during additive manufacturing. The legs 333, 334 are formed to fit within the cooling hole 200. The resilience of the legs 333, 334 enables the coating mask securing insert 330 to have a force applied to it to compress the legs 333, 334 toward each other in the gap 335. When in the cooling hole 200, the legs 333, 334 can decompress to frictionally engage the walls of the cooling hole 200 and hold the coating mask securing insert 330 therein. Thus, the legs 333, 334 frictionally hold the conformal coating mask 300 in the cooling hole 200 with the blade 100 together.

[0053] Further, the legs 333, 334 can be envisioned as a split conical structure. The base of the cone is formed on the bottom 339, and the cone is substantially "split" in half from the apex to the base. Each half from its apex is additively manufactured or formed spaced apart from each other in a "split" or spaced apart structure, while the base portion remains intact on the bottom surface 339 of the coating mask securing insert 330. Thus, the apex is configured to form a V-shaped gap 335 that is triangular in cross-section, as described herein.

[0054] As Figures 3 to 5 , Figure 8 and Figure 9 , the V-shaped gap 335 is configured to allow the coating mask securing insert 330 to have the legs 333, 334 compressed (as described herein) when inserted into the cooling hole 200. The compression of the legs 333, 334 can be by an appropriate external force, such as but by no means a limitation on the disclosure, a person's fingers applying pressure to the legs 333, 334 to move the legs 333, 334 toward each other and reduce the size of the V-shaped gap 335, thus the coating mask securing insert 330 can be inserted into the cooling hole 200. Alternatively, as described herein, when the conformal coating mask 300 is attached to the blade 100, the legs 333, 334 abutting the inner surface of the cooling hole 200 (see FIG. 6) will move the legs 333, 334 toward each other and compress. In each of the above cases, the legs 333, 334 of the coating mask securing insert 330 can decompress (at least to some extent) to frictionally hold the coating mask securing insert 330 in the cooling hole 200. Figure 3

[0055] ​Although legs 333 and 334 are shown as generally tapered configurations, they are merely examples of various possible configurations. Of course, if legs 333 and 334 have complementary and corresponding mating surfaces, the compression of legs 333 and 334 against the cooling hole 200 will be smoother. The configuration of legs 333 and 334 can be any shape, cross-section, and / or length consistent with and aligned with the cooling hole 200. Therefore, aspects of this disclosure include legs 333 and 334 having any configuration that allows legs 333 and 334 to be compressible into the cooling hole 200 and spring back to frictionally retain the coating mask retaining insert 330 within the cooling hole 200.

[0056] like Figure 3 As shown, each coating mask retaining insert 330 covers the surface 106 of the airfoil 105. The cover orientation and structure of the plug cover 331 are produced together with the simultaneous additive manufacturing of the plug cover 331 and the radial mask strip 303. The simultaneous formation of the conformal coating mask 300 and the assembly (here, the blade 100) allows the conformal coating mask 300 to match the surface tolerances of the blade 100, as described above, and allows the coating mask retaining insert 330 to align with the cooling holes 200 of the airfoil 105.

[0057] Figure 10 and Figure 11 Another embodiment of the insertion part 350 of at least one coating mask fixing insert 330 is shown. Figure 10 The insert 350 is shown in the form of an elongated spiral or spiral plug-out portion 351. The elongated spiral or spiral plug-out portion 351 is configured to extend into the cooling holes 200, 201, with or without engaging the sidewalls of the cooling holes 200, 201. Therefore, the elongated spiral or spiral plug-out portion 351 is configured to extend into the cooling holes 200, 201, and can be frictionally engaged or not engaged with the cooling holes 200, 201, simply positioning the elongated spiral or spiral plug-out portion 351 of the coating mask fixing insert 330 and the radial mask strip 303 thereon.

[0058] Figure 11 The fourth insert 350 is shown in the form of a sinusoidal portion 353. The sinusoidal portion 353 is configured to extend into the cooling holes 200, 201, with or without sidewalls engaging the cooling holes 200, 201. Therefore, the sinusoidal portion 353 is configured to extend into the cooling holes 200, 201, and may or may not engage with the cooling holes 200, 201, simply positioning the sinusoidal portion 353 of the coating mask fixing insert 330 and the radial mask strip 303 thereon.

[0059] For each insert part 350, the elongated spiral or auger shaped portion 351 or sinusoidal portion 353 and the radial mask strip 303 of the coating mask fixation insert 330 can be used with any configuration of the plug cap 331 as embodied herein. Additionally, the plug cap 331 can have an elongated spiral or auger shaped portion 351 or sinusoidal portion 353 or can not have a recess 340 as described herein.

[0060] The additive manufacturing process forms the coating mask fixation insert 330 with a configuration such that when the insert part 350 of the coating mask fixation insert 330 is inserted into the cooling hole 200, the bottom surface 339 of the coating mask fixation insert 330 covers the surface 106 at the cooling hole 200 at a distance A Figure 4 ) therebetween. The distance A is sufficient to prevent the coating from entering underneath the plug cap 331 to the surface 106. Thus, the coating does not enter underneath the plug cap 331 and does not sand up the cooling hole 200. By purposefully and advantageously setting the distance A, thereby eliminating the amount of coating underneath the plug cap 331, the conformal coating mask 300 prevents the coating material from falling around the cooling hole 200 and prevents sanding up between the cooling holes 200.

[0061] Referring to Figure 8 and Figure 9 In some aspects of the disclosure, the bottom surface 339 of the plug cap 331 is flat and can be formed by additive manufacturing to extend from the leg portions 333, 334. According to another aspect of the disclosure, the plug cap 331 includes a bottom surface 339 having a recess 340 Figure 5 ) formed to extend from the bottom surface 339 toward the top of the plug cap 331. The recess 340 reduces the amount of material required to form the conformal coating mask 300, the insert part 350, the radial mask strip 303, and the coating mask fixation insert 330. The recess 340 can also enhance any manipulation of the coating mask fixation insert 330 because the coating mask fixation insert 330 will be lighter and thus easier to move in and out of the cooling hole 200 as needed.

[0062] Once the vane 100 and the conformal coating mask 300 have been simultaneously printed by additive manufacturing, the conformal coating mask 300 can be aligned with the vane 100 for frictional engagement therewith. Thus, due to the simultaneous formation, the conformal coating mask 300 and its features match the surface tolerances and profile of the vane 100.

[0063] Referring to Figure 1To attach the conformal coating mask 300 to the vane 100, the anchors 301, 302 are positioned such that the end 320 and the first initial radial mask strip 303 are aligned with a row of cooling holes 200. Thus, the conformal coating mask 300 can be secured by having at least one insertion member 350 of the respective coating mask securing insert 330 enter or frictionally engage in the respective cooling hole 200. Thereafter, the anchors 310, 302 are moved to encircle the airfoil 105, and the coating mask securing insert 330 on each respective radial mask strip 303 can be aligned with and inserted into the respective cooling hole until the last terminal radial mask strip 303 associated with the end 322 can be aligned with the cooling holes 200 and the insertion member 350 of the respective coating mask securing insert 330 at the end 322 is inserted into the cooling holes 200.

[0064] Alternatively, another method for attaching the conformal coating mask 300 to the vane 100 positions the anchors 301, 302 such that the end 320 and the first initial radial mask strip 303 are aligned with a row of cooling holes 200. Thus, the conformal coating mask 300 can be secured by frictionally engaging at least one insertion member 350 of the coating mask securing insert 330 in the corresponding cooling hole 200 at the first initial radial mask strip 303. Thereafter, the anchors 310, 302 are moved to encircle the airfoil 105, and the coating mask securing insert 330 on each respective radial mask strip 303 can be aligned with the cooling holes 200 (but the insertion member 350 of the coating mask securing insert 330 is not inserted into the cooling holes 200). Next, the last terminal radial mask strip 303 associated with the end 322 can be aligned with a row of cooling holes 200 and the insertion member 350 of the respective coating mask securing insert 330 on the end 322 is inserted into the cooling holes 200. Then, once the first initial terminal radial mask strip 303 and the last terminal radial mask strip 303 are frictionally secured into the corresponding cooling holes 200, the remaining portion of the insertion member 350 of the coating mask securing insert 330 can be subsequently inserted into the cooling holes 200.

[0065] As can be seen from the instant description of embodiments, the conformal coating mask 300, the self-biasing anchors 301, 302, and the radial mask strips 303 each have a mask geometry sized and shaped to cover the cooling holes 200 to prevent coating from plugging the cooling holes 200. Thus, the overall configuration prevents coating sand plugs between the component surface and the edges of the conformal coating mask 300.

[0066] It will also be seen from the description of the embodiments that the features of the conformal coating mask 300 and its use on the blade 100 provide a method of masking a turbine component to block any holes in the turbine component during a post-formation coating process. The method includes forming the conformal coating mask 300 and the turbine blade 100 simultaneously by additive manufacturing. After formation, the conformal coating mask 300 is positioned to cover the blade 100, so that the at least one closed plug covers the at least one corresponding cooling hole 200. A force is applied to one or more of the coating mask securing inserts 330 or the radial mask strips 303, thereby moving the at least one, but preferably all, of the insert components 350 into the corresponding cooling holes 200.

[0067] The coating (or other post-formation process) can be performed and the coating prevented from entering the cooling holes 200 on the blade 100 by the insert coating mask securing inserts 330. Furthermore, even in the case where no coating mask securing inserts 330 are provided or inserted into the cooling holes 200, the coating can be prevented from entering the cooling holes 200 because the at least one radial mask strip 303 covers a column of closely proximate cooling holes 200. Each radial mask strip 303 will mask a column of cooling holes 200. Thus, not every cooling hole 200 can need a corresponding coating mask securing insert 330 and masking can still be achieved. In other words, the coating mask securing inserts 330 serve to align and secure the mask strips 303 in place in the event that one of the anchors 301, 302 breaks. The embodiments herein do not require an insert component 350 and a coating mask securing insert 330 for every cooling hole, but the mask strip 303 over every cooling hole 200 will prevent the coating from entering the hole.

[0068] Once any post-formation process is complete, the conformal coating mask 300 can be removed by lifting any portion of the conformal coating mask 300, such as but not limited to the anchors 301, 302, the radial mask strips 303, or any coating mask securing inserts 330.

[0069] Another aspect of the present disclosure provides a method of masking a turbine component to block any holes in the turbine component during a post-formation process. The method includes forming a conformal coating mask by additive manufacturing simultaneously with the turbine component by additive manufacturing. Forming the conformal coating mask includes integrally forming, by additive manufacturing: at least two anchors; a plurality of radial mask strips integrally formed with each of the at least two anchors and extending between the at least two anchors; and at least one coating mask securing insert. Each of the at least one coating mask securing insert is integrally formed with a respective at least one radial mask strip, wherein the plurality of radial mask strips are aligned with and cover a plurality of cooling holes.

[0070] As used throughout the specification and claims, approximate language can be used to modify any quantitative representation that can allow for variation, and is intended to cover any and all changes, substitutions, and alterations in the described quantities that do not materially affect the basic function to which the quantity is directed. Thus, a value modified by one or more terms such as “about,” “approximately,” and “substantially” is not limited to the precise value specified. In at least some instances, the approximate language can correspond to the precision of an instrument used to measure the value. Ranges can be combined and / or interchanged, here and throughout the specification and claims. Unless otherwise specified, these ranges are recognized and include all sub-ranges contained therein. “About” applied to numerical values means + / - 10% of the recited value, unless otherwise indicated, as can be dependent on the precision of the instrument measuring the value.

[0071] All devices or steps plus functional language in the claims of the following claims are intended to encompass any structure, material, or acts for performing the functions described in connection with other claimed elements. The description of the present disclosure has been presented for purposes of illustration and description, but is not intended to be exhaustive or to limit the present disclosure to the forms disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the present disclosure. Embodiments were chosen and described in order to best explain the principles of the present disclosure and the practical application, and to enable others skilled in the art to understand various embodiments of the present disclosure with various modifications as are suited to the particular use contemplated.

Claims

1. A conformal coating mask (300) for use with a turbine component having a plurality of cooling holes (201), the conformal coating mask (300) comprising: at least two anchors (301, 310); a plurality of radial mask strips (303) integrally formed with each of the at least two anchors (301, 310) and extending between the at least two anchors (301, 310); and at least one coating mask fixation insert (330), each coating mask fixation insert of the at least one coating mask fixation insert integrally formed with a respective at least one radial mask strip (303); wherein the plurality of radial mask strips (303) are aligned with and cover the plurality of cooling holes (201).

2. The conformal coating mask (300) of claim 1, wherein the at least two anchors (301, 310), the plurality of radial mask strips (303), and the at least one coating mask fixation insert (330) are integrally formed by additive manufacturing.

3. The conformal coating mask (300) of claim 1, wherein each coating mask fixation insert of the at least one coating mask fixation insert (330) comprises: a plug cover (331); and an insertion component (350) capable of entering at least one cooling hole (200).

4. The conformal coating mask (300) of claim 3, wherein the insertion component (350) frictionally engages a wall of the at least one cooling hole (200).

5. The conformal coating mask (300) of claim 3, wherein the insertion component (350) comprises a sinusoidal portion (353).

6. The conformal coating mask (300) of claim 3, wherein the insertion component (350) comprises an elongated helical portion.

7. The conformal coating mask (300) of claim 3, wherein the insertion component (350) comprises a compressible portion (332) comprising a plurality of compressible legs (333, 334) integrally formed with the plug cover (331), the plurality of compressible legs (333, 334) separated from each other by a gap (335), the plurality of compressible legs (333, 334) capable of being moved into the gap (335) by a force exerted on the plurality of compressible legs (333, 334), wherein the plurality of compressible legs (333, 334) return from the gap (335) once the force is removed.

8. The conformal coating mask (300) of claim 7, wherein the plurality of compressible legs (333, 334) comprises only two compressible legs (333, 334).

9. The conformal coating mask (300) of claim 7, wherein the gap (335) is triangular in cross-sectional shape.

10. The conformal coating mask (300) of claim 3, wherein the plug cap (331) includes a raised top portion and has an elliptical perimeter.

11. The conformal coating mask (300) of claim 3, wherein the plug cap (331) includes a raised top portion and has a circular perimeter.

12. The conformal coating mask (300) of claim 3, wherein a bottom surface (339) of the plug cap (331) includes a recess (340).

13. A conformal coating mask system, the system comprising: A turbine component and a conformal coating mask (300) formed simultaneously with the component; The turbine component includes an airfoil (105, 205) and a plurality of cooling holes (201) therein; The conformal coating mask (300) includes: at least two anchors (301, 310); a plurality of radial mask strips (303) integrally formed and extending between the at least two anchors (301, 310); and at least one coating mask fixation insert (330) integrally formed with a respective one of the plurality of radial mask strips (303); wherein the plurality of radial mask strips (303) are aligned with and cover the plurality of cooling holes (201).

14. The system of claim 13, wherein the at least one coating mask fixation insert each includes a plug cap; and an insert component that can not enter at least one cooling hole.

15. The system of claim 14, wherein the insert component that can not enter at least one cooling hole includes at least one of: a plurality of legs integrally formed with the plug cap, the plurality of legs extending from a bottom surface of the plug cap to frictionally engage a wall of a cooling hole; a sinusoidal curve portion; and an elongated helical portion.

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