The subject matter disclosed herein relates to manufacturing and repair of components. More specifically, the subject matter disclosed herein relates to approaches of manufacturing and/or repairing components to manage material stress.
During operation, turbomachine components, such as turbomachine blades and nozzles, are subjected to high temperatures, pressures and/or stresses over extended periods. In many cases, particular portions of these components can be subject to differential stresses due to their geometry and location relative to a working fluid (e.g., gas or steam). For example, a blade platform or tip, or a nozzle sidewall, can be subject to different warmup and cool down rates than the airfoil of that same blade or nozzle. This differential thermal inertia can cause tensile stress at or near the platform and/or tip (or sidewall). These tensile stresses may contribute to cracking or other material fatigue, and ultimately can require repair and/or maintenance.
Various aspects of the disclosure include a composite turbomachine component and methods of forming such a component. In a first aspect, a method includes: identifying a location of potential or actual structural weakness in a body of a turbomachine component, the body including a first material having a first thermal expansion coefficient; forming a slot in the location of the body, the slot extending at least partially through a wall of the turbomachine component; and bonding an insert to the body at the slot to form a composite component, the insert including a second material having a second thermal expansion coefficient, the second thermal expansion coefficient differing from the first thermal expansion coefficient by up to approximately ten percent, the second material consisting of a nickel-chrome-molybdenum alloy, wherein after the bonding the insert is configured to reduce the potential or actual structural weakness in the body.
A second aspect of the disclosure includes a composite turbomachine component having: a body including: a wall; and a slot extending at least partially through the wall, wherein the body includes a first material having a first thermal expansion coefficient, the first material including at least one of: steel, at least one nickel-chromium superalloy, at least one cobalt-based superalloy or at least one nickel-based superalloy; an insert substantially filling the slot, the insert including a second material having a second thermal expansion coefficient, the second thermal expansion differing from the first thermal expansion coefficient by up to approximately ten percent, the second material consisting of a nickel-chromium-molybdenum alloy; and a weld or braze joint coupling the insert to the body at the slot.
These and other features of this disclosure will be more readily understood from the following detailed description of the various aspects of the disclosure taken in conjunction with the accompanying drawings that depict various embodiments of the disclosure, in which:
It is noted that the drawings of the disclosure are not necessarily to scale. The drawings are intended to depict only typical aspects of the disclosure, and therefore should not be considered as limiting the scope of the disclosure. In the drawings, like numbering represents like elements between the drawings.
The subject matter disclosed herein relates to manufacturing and/or repair. More specifically, the subject matter disclosed herein relates to composite components with materials of distinct thermal expansion coefficients, and methods of forming those components.
In contrast to conventional approaches, various aspects of the disclosure include a composite turbomachine component, and methods of forming such a component. In various embodiments, the composite turbomachine component has a body and an insert filling a slot in the body, where the location of the slot is determined based upon an expected or actual amount of material fatigue in that portion of the body. The insert can be welded to the body at the slot, but in some cases, the insert could also be brazed to the body at the slot. In various embodiments, the body of the turbomachine component is formed of steel or an alloy, such as at least one nickel-chromium superalloy, at least one cobalt-based superalloy or at least one nickel-based superalloy (e.g., Inconel-738, Inconel-939, Udimet 500 and Udimet 700, from Special Metals Corp., New Hartford, N.Y.; or GTD-111, GTD-222, GTD-241, GTD-741 or GTD-141 (from the General Electric Company, Boston, Mass.); or FSX-414). In various embodiments, the insert can include a material having a distinct thermal expansion coefficient from the material of the body, e.g., approximately 0.9 to approximately 1.1 times the thermal expansion coefficient of the body. In some cases, the insert can include a nickel-chromium-molybdenum alloy (e.g., Nimonic 263, from the Special Metals Corp or Haynes 230, from Haynes International, Inc., Kokomo, Ind.), and in some particular cases, the insert can consist substantially entirely (e.g., given nominal other materials) of a nickel-chromium-molybdenum alloy. The location of the slot (and insert) is determined based upon a model (e.g., a finite element analysis model) of the turbomachine component, or an observed wear on the turbomachine component (e.g., via human operator inspection, or with an optical inspection system, florescent inspection system, infra-red inspection system). The slot (and insert) may be located within a portion of the platform, in the case of a turbomachine blade, or a sidewall, in the case of a turbomachine nozzle. In some other cases, the slot (and insert) can be located proximate the tip of the airfoil, e.g., in a “Z-notch” region of the blade. The composite turbomachine component may be stronger than conventional turbomachine components formed of a uniform or substantially uniform material composition.
In some particular cases, the slot is machined from the body, e.g., by cutting, sanding or otherwise abraded the location in the body for the insert. After the insert is placed in the slot, it may be welded, brazed or otherwise heat-treated to bond with the body and fill the slot. After bonding the insert to the body at the slot, the surface of the insert and the body may be machined, e.g., grinded, sanded, or otherwise planarized to form a surface profile consistent with the original design of the blade.
In various embodiments, the composite component can include a refurbished component, e.g., where the body is an original part having gone through field use and the insert is a replacement portion of the component. In other cases, the composite component can include two original parts (either having gone through field use, or not) joined at an interface, and in other cases, the composite component can include two replacement parts joined at an interface.
In the following description, reference is made to the accompanying drawings that form a part thereof, and in which is shown by way of illustration specific embodiments in which the present teachings may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the present teachings and it is to be understood that other embodiments may be utilized and that changes may be made without departing from the scope of the present teachings. The following description is, therefore, merely illustrative.
With reference to
Process P1: identifying a location 100 of potential or actual structural weakness in a body 110 of turbomachine component 2. In various embodiments, body 110 includes a first material having a first thermal expansion coefficient. That is, in some cases, body 110 of component 2 is composed entirely, or approximately (e.g., within 1-3 percent) entirely of, a first material, which has a first thermal expansion coefficient. In some cases, the first material includes steel. It is understood that the first material or second material may include impurities to the extent acceptable in conventional turbomachine components. In some particular cases, the first material can include a steel or an alloy such as at least one nickel-chromium superalloy, at least one cobalt-based superalloy or at least one nickel-based superalloy (e.g., Inconel-738, Inconel-939, Udimet 500 and Udimet 700, from Special Metals Corp., New Hartford, N.Y.; or GTD-111, GTD-222, GTD-241, GTD-741 or GTD-141 (from the General Electric Company, Boston, Mass.); or FSX-414). In various embodiments, the thermal expansion coefficient of the first material (at an example temperature of approximately 815 degrees Celsius (1500 degrees Fahrenheit)) is approximately 8×10−5 in/(in F). The location 100 of potential or actual structural weakness in body 110 can be identified according to various embodiments. In some cases, location 100 can be identified by a user 120, e.g., a user such as a human user, robotic user or other machine. In some cases, user 120 can include, or work in conjunction with, an inspection system 130 for analyzing turbomachine component 2 to detect one or more location(s) 100 of potential or actual structural weakness. In some cases, inspection system 130 can include at least one of an optical scanner, an infrared scanner or a fluorescent inspection system. Inspection system 130 can include conventional scanning/inspection components such as laser-based detection components, infrared sensors, transmitters, receivers, transducers, etc. Where user 120 is a human user, that human user may visually inspect turbomachine component 2 to detect one or more location(s) 100 of potential or actual structural weakness. It is understood that user 120 and/or inspection system 130 may be particularly useful in detecting location(s) 100 of actual structural weakness, e.g., locations of visible or physically detectable cracks, deformations, material fatigue, etc. In some particular cases, a user 120 (e.g., human user) can use an inspection system 130, such as a fluorescent inspection system or a blue-light scanner to visually inspect component 2 to detect one or more locations 100 of structural weakness.
In some other embodiments, identifying location(s) 100 can include performing a finite element analysis on a data file 140 representing turbomachine component 2. In these embodiments, data file 140 can include a computer-aided design (CAD) file or other data model representing turbomachine component 2. In some cases, data file 140 can be used to form turbomachine component 2 or another similar component. In various embodiments, a turbomachine component analysis system (analysis system) 150 can be used to analyze data file 140 to identify location(s) 100 in turbomachine component 2 of potential or actual structural weakness. In particular cases, turbomachine analysis system 150 can be configured to identify locations(s) 100 of potential structural weakness in turbomachine component 2, e.g., based upon a modeled response of turbomachine component 2 to expected operating conditions such as particular temperature ranges, pressure ranges, fatigue cycles, warmup/cooldown cycles, etc. In various embodiments, turbomachine component analysis system 150 can be stored or otherwise deployed by a conventional computer system 200 having a processor (PU) 210, memory 220, storage device 230 and an input/output (I/O) device 240. Turbomachine component analysis system 150 can include one or more logic engines (or modules) 250 for executing commands to analyze data file 140 according to various embodiments described herein. In particular cases, data file 140 can include a three-dimensional (3D) model of the component 2, and analysis system 150 can include a software program for analyzing low-cycle fatigue and/or crack propagation in the 3D model, such as conventional simulation software (e.g., ANSYS Mechanical, from ANSYS, Inc., Canonsburg, Pa.).
According to various embodiments, where turbomachine component 2 includes a blade 10, location 100 may be within platform 16 or tip shroud 20, proximate airfoil 18.
Process P2: after identifying location 100, according to various embodiments, the process can further include forming a slot 300 (
Process P3: after forming slot 300 in component 2, bonding an insert 400 (
Process P4 (optional post-process): in some cases, after bonding insert 400 to body 110 of component 2, an additional process can include planarizing an outer surface 430 of body 110 and insert 400 proximate slot 300. In various embodiments, planarizing can include conventional machining processes such as sanding, grinding, polishing or otherwise smoothing outer surface 430 of body 110 and insert 400 proximate slot 300.
As shown in
It is understood that the processes described herein can be performed in any order, and that some processes may be omitted, without departing from the spirit of the disclosure described herein.
One or more portions of composite component 410 (
To illustrate an example of an additive manufacturing process,
AM control system 904 is shown implemented on computer 930 as computer program code. To this extent, computer 930 is shown including a memory 932, a processor 934, an input/output (I/O) interface 936, and a bus 938. Further, computer 930 is shown in communication with an external I/O device/resource 940 and a storage system 942. In general, processor 934 executes computer program code, such as AM control system 904, that is stored in memory 932 and/or storage system 942 under instructions from code 920 representative of at least a portion of composite component 410 (
Additive manufacturing processes begin with a non-transitory computer readable storage medium (e.g., memory 932, storage system 942, etc.) storing code 920 representative of at least a portion of composite component 410 (
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.
Number | Date | Country | Kind |
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17461553.4 | Jun 2017 | EP | regional |