The present disclosure relates generally to rotary machines and, more specifically, to systems and methods for positioning masking plugs on a component of a rotary machine.
At least some known rotary machines, such as gas turbines, include components, such as turbine nozzles, rotor blade airfoils, and/or shrouds, formed from a substrate over which a coating is applied. At least some of such components include surface features, such as cooling apertures, that extend through the coating and into, and/or through, the substrate. Repair of some such components requires the coating to be removed from, and subsequently reapplied to, the substrate. Surface features previously formed in the substrate remain after the substrate has been repaired. However, in at least some cases, recoating the component may undesirably obstruct and/or obscure surface features located on the underlying substrate.
At least some known repair methods include positioning plugs over the surface features in the substrate prior to the coating being reapplied, such that the plugs inhibit the coating material from obstructing the surface features. However, where a large number of surface features are present on the component, a large amount of time and effort may be required to properly position a plug over each surface feature, and then to later remove the plugs after the coating is reapplied.
In one aspect, a tool for positioning a masking plug relative to a surface feature on a component is provided. The tool includes a body extending from a first end to an opposite second end. The second end is configured to couple to an attachment tool. The tool further includes a channel defined in the first end. The channel is sized to receive at least a portion of the masking plug therein such that rotational motion of the tool about a longitudinal axis is transferred to the masking plug. The tool is operable to releasably secure the masking plug to the first end.
In a further aspect, a system for use in positioning a masking plug relative to a surface feature on a component is provided. The system includes a masking plug including a first projection configured to extend within the surface feature. The system further includes a tool including a body configured to couple to an attachment tool. The tool further includes a channel defined in the body. The channel is sized to receive at least a portion of the masking plug such that rotation of the tool causes rotation of the masking plug. The tool is operable to releasably secure the masking plug to the body.
In another aspect, a method of positioning a masking plug relative to a surface feature on a component is provided. The method includes coupling an attachment tool to a tool including a channel therein. The tool extends from a first end to an opposite second end. The method further includes receiving at least a portion of the masking plug in the channel such that rotational motion of the tool causes rotation of the masking plug and such that the masking plug is releasable secure to the first end. The method additionally includes positioning the tool relative to the surface feature on the component.
The exemplary tools and methods described herein overcome at least some of the disadvantages associated with known repair tools and methods for applying a coating material on a component including surface features. The embodiments described herein include a tool that includes a channel sized to receive at least a portion of a masking plug therein, such that rotational motion of the tool causes rotation of the masking plug. The tool is configured to couple to an attachment tool, and is further operable to selectively couple the masking plug to the component. In certain embodiments, the tool includes an aperture defined therein and positioned such that the masking plug may be releasably secured to the tool, when negative pressure is induced through the aperture. In each embodiment, the tool is configured to releasably couple the masking plug to a substrate of the component prior to a coating being applied to the substrate.
Unless otherwise indicated, approximating language, such as “generally,” “substantially,” and “about,” as used herein indicates that the term so modified may apply to only an approximate degree, as would be recognized by one of ordinary skill in the art, rather than to an absolute or perfect degree. Approximating language 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,” “approximately,” and “substantially,” are not to be limited to the precise value specified. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value. Here and throughout the specification and claims, range limitations may be identified. Such ranges may be combined and/or interchanged, and include all the sub-ranges contained therein unless context or language indicates otherwise.
Additionally, unless otherwise indicated, the terms “first,” “second,” etc. are used herein merely as labels, and are not intended to impose ordinal, positional, or hierarchical requirements on the items to which these terms refer. Moreover, reference to, for example, a “second” item does not require or preclude the existence of, for example, a “first” or lower-numbered item or a “third” or higher-numbered item.
As used herein, the terms “axial” and “axially” refer to directions and orientations extending substantially parallel to a longitudinal axis of a rotary machine. Moreover, the terms “radial” and radially” refer to directions and orientations extending substantially perpendicularly to the longitudinal axis of the turbomachine. In addition, as used herein, the terms “circumferential” and “circumferentially” refer to directions and orientations extending arcuately about the longitudinal axis of the turbomachine. The term “fluid” as used herein includes any medium or material that flows, including, but not limited to, air. As used herein, the term “component” refers to any structure within a rotary machine that includes surface features that may be obscured and/or blocked by coating material during reapplication of a coating following repair of the surface. In addition, although embodiments of the disclosure are described with reference to components of rotary machines, it should be understood that the scope of the disclosure encompasses any suitable component of any suitable structure for which the embodiments are enabled to function as described herein.
In the exemplary embodiment, a flow 138 of hot combustion gases is channeled through a rotor/stator cavity 139, exposing an outer surface 124 of nozzle 112, an outer surface 132 of airfoil 130, and an outer surface 126 of nozzle 114 to high temperatures and/or corrosive agents. To at least partially address such exposure, at least one of nozzle 112, airfoil 130, nozzle 114, and any other suitable hot component in turbine assembly 106 is provided with a suitable protective coating, such as, but not limited to, a ceramic and/or heat-resistant coating (not numbered). To further at least partially address such exposure, at least one of nozzle 112, airfoil 130, nozzle 114, and any other suitable hot component in turbine assembly 106 is provided with a cooling system 134. Cooling system 134 includes a suitable cooling air supply channel (not shown) coupled to at least one suitable subsurface passage (not shown) that terminates, for example, in at least one surface feature 136 in the at least one hot component. In the illustrated embodiment, for example, cooling system 134 is at least partially defined in nozzle 112, and surface feature 136 is defined in outer surface 124 of nozzle 112.
In the exemplary embodiment, component substrate 140 includes a plurality of surface features 146 defined in an outer surface 142 of component substrate 140. Moreover, in the exemplary embodiment, surface features 146 are sized substantially identically and each surface feature 146 has a substantially uniform diameter 144. Furthermore, in the exemplary embodiment, surface features 146 are uniformly spaced 148 and 149. In alternative embodiments, at least one surface feature 146 has a different diameter than other surface features 146 and/or at least some surface features 146 are not uniformly spaced.
In the exemplary embodiment, nozzle 112 is formed from component substrate 140 by applying the protective coating to outer surface 142. However, in order to form nozzle 112 surface features 146, the protective coating must be inhibited from entering and/or obstructing surface features 146 defined in component substrate 140. In the exemplary embodiment, at least one masking plug 150 is coupled to surface feature 146 of component substrate 140 prior to the protective coating being applied to outer surface 142.
In the exemplary embodiment, masking plug 150 includes a body 152, a first projection 154 extending outwardly from body 152, and a second projection 156 extending outwardly from body 152 in an opposite direction than first projection 154. First projection 154 is sized to extend partially into surface feature 146 (shown in
Second projection 156 of masking plug 150 may be releasably secured to first end 206 of tool 202, as will be described further herein. In the exemplary embodiment, second projection 156 has a shape that is substantially complementary to a first end 206 of tool 202, such that second projection 156 is at least partially receivable within first end 206 of tool 202. In alternative embodiments, second projection 156 has any other suitable shape that enables masking plug 150 to function as described herein.
Tool 202 is removably coupleable to an attachment tool 220. More specifically, in the exemplary embodiment, a second end 208 of tool 202 is removably coupleable to attachment tool 220, as will be described in more detail herein. In alternative embodiments, tool 202 is removably coupleable to attachment tool 220 in any other suitable fashion that enables plug positioning system 200 to function as described herein.
In the exemplary embodiment, attachment tool 220 is selectively operable to move tool 202 in a plurality of directions. More specifically, attachment tool 220 is operable to translate and orient tool 202 relative to outer surface 142 (shown in
In the exemplary embodiment, a channel 210 is defined in first end 206. Channel 210 is sized and oriented to receive at least a portion of masking plug 150, such that rotational motion of tool 202 about longitudinal axis 226 is transferred to masking plug 150. For example, in the exemplary embodiment, channel 210 has a shape that substantially mirrors a perimeter of body 152 of masking plug 150 (shown in
In the exemplary embodiment, a recess 216 is defined within channel 210 and in flow communication with channel 210. Recess 216 is sized to receive a perimeter of second projection 156 of masking plug 150 (shown in
In the exemplary embodiment, an aperture 222 is defined within body 204 and in flow communication with first end 206 and second end 208. More specifically, in the exemplary embodiment, aperture 222 extends generally parallel to longitudinal axis 226 between, and in flow communication with, channel 210 and body bore 218. First end 206 of tool 202 is sized to secure masking plug 150 to tool 202 in response to a negative pressure induced within aperture 222, and to decouple tool 202 from masking plug 150 in response to a positive pressure induced within aperture 222, as will be described below.
In the exemplary embodiment, attachment tool 220 is suitably operable to selectively induce each of a negative pressure and a positive pressure within aperture 222 of tool 202. In operation, to secure masking plug 150 (shown in
Further in operation, to release masking plug 150 (shown in
With reference to
In the exemplary embodiment, tool 202 also is selectively operable to releasably couple masking plug 150 to component substrate 140. For example, coupling masking plug 150 to component substrate 140 facilitates maintaining masking plug 150 in the selected masking position during a coating process of component substrate 140, thus further facilitating inhibition of the coating from entering and/or obstructing surface feature 146.
More specifically, in the exemplary embodiment, at least a portion of surface 224 of body 204 is coated with an electrically-conductive material, such that tool 202 is operable to weld masking plug 150 to component substrate 140. For example, at least a portion of surface 224 is formed from an electrically-conductive coating applied to body 204. In the exemplary embodiment, surface 224 includes a highly conductive copper plated material. In alternative embodiments, surface 224 includes any other suitable highly conductive material that conducts electric current and enables tool 202 to function as described herein such as, but not limited to, brass, copper, bronze, and steel. In addition, masking plug 150 is at least partially formed from a material that becomes coupled to component substrate 140 in response to an electric current. For example, masking plug 150 is a plastic material that heats under electric current and adheres to component substrate 140. In alternative embodiments, masking plug 150 includes any other suitable material that enables tool 202 to function as described herein.
Further in the exemplary embodiment, attachment tool 220 is operable to selectively apply an electric current to surface 224 of body 204. For example, in the exemplary embodiment, attachment tool 220 includes electrodes 228 configured to selectively apply an electrical current to body 204 when second end 208 is coupled to attachment tool 220. The electric current is conducted through surface 224, masking plug 150, and component substrate 140, causing masking plug 150 to become welded to component substrate 140. The highly conductive coating is operable to weld masking plug 150 to component substrate 140 without welding body 204 to component substrate 140.
In the exemplary embodiment, tool 202 also is selectively operable to decouple masking plug 150 from component substrate 140. For example, after the coating is reapplied to component substrate 140, masking plug 150 is decoupled and removed from component substrate 140 to uncover surface feature 146 (shown in
More specifically, in the exemplary embodiment, attachment tool 220 is selectively operated to translate and orient tool 202 relative to outer surface 142 such that channel 210 of tool 202 is secured to second projection 156 of masking plug 150. Attachment tool 220 is then selectively operated to rotate tool 202 about longitudinal axis 226. Tool 202 urges masking plug 150 to rotate with tool 202, as described above, thereby tending to decouple the weld and/or other attachment between masking plug 150 and stationary component substrate 140. In certain embodiments, attachment tool 220 is further selectively operated to move masking plug 150 away from outer surface 142 without damaging the coating. For example, attachment tool 220 is selectively operated to induce negative pressure to aperture 222, such that masking plug 150 remains secured to tool 202 after decoupling from component substrate 140, and attachment tool 220 is selectively operated to translate and orient tool 202 relative to outer surface 142 to move masking plug 150 away from outer surface 142.
For example, in the exemplary embodiment, a second aperture 230 is defined within body 204. A first end 232 of second aperture 230 is defined in first end 206 of tool 202 and extends therethrough, and a second end 234 of second aperture 230 is defined is in body bore 218 of tool 202 and extends therethrough. Moreover, attachment tool 220 includes a supply aperture 236 configured to couple in flow communication with second end 234 when attachment tool 220 is received within body bore 218. Attachment tool 220 is selectively operable to channel adhesive from a suitable source through supply aperture 236 and into second end 234 of second aperture 230.
In operation, tool 202 is coupled to second projection 156 of masking plug 150 by selectively operating attachment tool 220 to induce a negative pressure to first aperture 222, and attachment tool 220 is selectively operated to translate and orient tool 202 relative to outer surface 142 such that first projection 154 is received within surface feature 146 and masking plug 150 masks surface feature 146, as described above with respect to the first embodiment. Attachment tool 220 also is selectively operated to flow adhesive through supply aperture 236 and into second aperture 230, such that adhesive flows through second aperture 230 and out first end 232 of second aperture 230, and thus spreads onto masking plug body 152 and component substrate 140. The adhesive quickly sets sufficiently to couple masking plug 150 to component substrate 140. Tool 202 also is selectively operable to uncouple masking plug 150 from component substrate 140, as described above. For example, after the coating is reapplied to component substrate 140, masking plug 150 is decoupled and removed from component substrate 140 to uncover surface feature 146 (shown in
In operation, to secure masking plug 150 to tool 202, second projection 156 of masking plug 150 is positioned within channel 210, and electrical connection 244 of attachment tool 220 is selectively operated to induce an electric current to conductive coupling 242 of tool 202. The electric current is supplied to electromagnetic material 240, which is responsive to the electric current to produce an electromagnetic force that tends to secure the magnetically attractable material of masking plug 150 to tool 202, such that masking plug 150 is movable with tool 202.
Further in operation, to decouple masking plug 150 from tool 202, electrical connection 244 of attachment tool 220 is selectively operated to remove the electric current to conductive coupling 242 of tool 202. The electromagnetic field generated by electromagnetic material 240 dissipates, removing the attractive force on masking plug 150 and facilitating the release of masking plug 150 from tool 202.
Although not shown in
Additionally, although systems for securing and releasing masking plug 150 from tool 202, such as inducing a negative pressure and a positive pressure within aperture 222, as illustrated in
An exemplary method 300 of positioning masking plug 150 relative to surface feature 146 on component substrate 140, shown in
In certain embodiments, method 300 includes securing 308 masking plug 150 to first end 206 via magnetic force when masking plug 150 includes a magnetically attractable material and tool 202 includes electromagnetic material 240 adjacent to channel 210.
In some embodiments, method 300 includes securing 310 masking plug 150 to tool 202 by inducing a negative pressure in aperture 222 when aperture 222 is defined in body 204 and in flow communication first end 206 and second end 208. In alternative embodiments, method 300 includes releasing 312 tool 202 from masking plug 150 by inducing a positive pressure in aperture 222.
In certain embodiments, method 300 includes inducing 314 an electric current to a coating such that masking plug 150 is welded to component substrate 140 when surface 224 of body 204 is coated with an electrically-conductive coating. In alternative embodiments, method 300 further includes rotating 316 tool 202 about longitudinal axis 226 such that masking plug 150 secured to first end 206 is rotatably uncoupled from surface feature 146.
In some embodiments, method 300 includes coupling 318 second end 208 of aperture 230 in flow communication with a source of adhesive, such as attachment tool 220 and flowing 320 the adhesive through aperture 230 and out first end 232 of second aperture 230 releasably coupling masking plug 150 to component substrate 140. In alternative embodiments, method 300 further includes rotating 322 tool 202 about longitudinal axis 226 such that masking plug 150 secured to first end 206 is rotatably uncoupled from surface feature 146.
Exemplary embodiments of tools and methods for positioning masking plugs relative to a surface feature on a component are described above in detail. The embodiments described herein provide several advantages in positioning masking plugs. Specifically, the tool and methods described herein facilitate masking and unmasking surface features on components during repair to inhibit obstruction of the surface features. The embodiments described herein provide advantages in that the masking plug is releasably securable to the tool, while an attachment tool, such as but not limited to an end effector, moves the masking plug into a selected position and orientation for coupling to the component. The embodiments also provide an advantage in that the same tool is rotatable to decouple the masking plug from the component, such as after a coating is applied to the substrate. Certain embodiments provide a further advantage in that the tool facilitates releasably coupling the masking plug to the component substrate such that the masking plug is not displaced, for example during the application of the coating to the substrate. Thus, the tools and methods described herein enable a more economical and automated positioning of masking plugs during component repair.
The tools and methods described herein are not limited to the specific embodiments described herein. For example, components of each system and/or steps of each method may be used and/or practiced independently and separately from other components and/or steps described herein. In addition, each component and/or step may also be used and/or practiced with other assemblies and methods.
While the disclosure has been described in terms of various specific embodiments, those skilled in the art will recognize that the disclosure can be practiced with modification within the spirit and scope of the claims. Although specific features of various embodiments of the disclosure may be shown in some drawings and not in others, this is for convenience only. Moreover, references to “one embodiment” in the above description are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. In accordance with the principles of the disclosure, and feature of a drawing may be referenced and/or claimed in combination with any feature of any other drawing.