The present application relates to flexible seal assemblies, and more specifically, flexible seal assemblies having a relatively low torsional rigidity and high longitudinal flexure to thereby allow the flexible seal assembly to flex between adjacent components and maintain a seal, even when movement between adjacent components occurs.
In many industrial applications, such as gas turbines and aerospace turbines, several components are assembled together in a circular and/or segmented fashion. These arrangements typically result in the creation of gaps between adjacent segments. Such gaps are generally undesirable, as they create paths for air and gas leaks that, if not filled or closed, decrease operation efficiency.
Historically, these gaps have been filled using cloth seals or laminate seals. However, both solutions provide limitations in one or more of flexure, durability, sealing, and temperature resistance. For example, problems associated with previously known seals used to fill gaps between adjacent components include leakage along the longitudinal axis, lack of durability (e.g., brittleness), increased number of potential leak paths, wear issues, lack of compliancy, and limited resiliency.
Accordingly, a need exists for improved sealing assemblies that reduce or eliminate some or all of these limitations.
This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary, and the foregoing Background, is not intended to identify key aspects or essential steps of the claimed subject matter. Moreover, this Summary is not intended for use as an aid in determining the scope of the claimed subject matter.
Described herein are various embodiments of a flexible seal assembly suitable for use in applications such as gas turbines or aerospace turbines where a flat seal between adjacent components is required in order to improve operating efficiency. In some embodiments, the flexible seal assembly comprises one or more layers of a metal matrix sheet material, and a metal casing fully or partially encapsulating the one or more layers of the metal matrix sheet material. The metal matrix sheet material can be made from a plurality of segments of thin wire arranged in a random fashion to create a sheet structure, and which are then sintered together to form a semi-rigid sheet. The metal casing can be made of a metal alloy.
This composite structure provides a flexible seal assembly that has a relatively low torsional rigidity and high longitudinal flexure to thereby allow the flexible seal assembly to flex between adjacent components and maintain a seal, even when movement between adjacent components occurs. The low torsional rigidity/high longitudinal flexure also reduces wear to the components that come into contact with the seal assembly that can be caused by previously known rigid seal assemblies. Additionally, the casing protects the interior metal matrix sheet material to thereby improve the operational lifetime of the seal assembly, but without sacrificing the flexibility of the seal assembly.
Non-limiting and non-exhaustive embodiments of the disclosed flexible sealing assembly, including the preferred embodiment, are described with reference to the following figures, wherein like reference numerals refer to like parts throughout the various views, uncles otherwise specified.
Embodiments are described herein more fully below with reference to the accompanying Figures, which form a part hereof and show, by way of illustration, specific exemplary embodiments. These embodiments are disclosed in sufficient detail to enable those skilled in the art to practice the invention. However, the embodiments may be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein. The following Detailed Description is, therefore, not to be taken in a limiting sense.
With reference to
Each metal matrix sheet material layer 110a, 110b, 110c is generally comprised of multiple segments of thin wire arranged at random and sintered together to form a semi-rigid sheet material. The material of the thin wire used to create the shorter segments can generally be any suitable type of metal material and will typically have a diameter of less than 0.010 inches. The thin wire is cut into short segments, such as segments having an aspect ratio of around 20. For example, when the diameter of the thin wire is 0.010 inches, the length of the individual segments cut from the wire is typically in the range of 0.200 inches.
The thickness of a layer of the metal matrix sheet material is generally not limited, and may be as thin as approximately the two times the diameter of the wire segments used. The thickness of the metal matrix sheet material can be increased by using more segments piled on top of each other when the segments are randomly arranged to form the sheet structure.
The randomly arranged segments are sintered in order to bond together segments that contact one another. Sintering is generally carried out by using a heat-treating process. Any temperature can be used for the sintering step provided that the temperature is sufficient to bond together the metal segments without destroying the structural integrity of the wires. Similarly, the sintering can be carried out for any period of time provided that the bonding together of metal segments occurs. Other processing steps can also be used in the creation of the sheets, such as additional sintering steps and/or calendaring steps. Such additional processing steps can be used to achieve, for example, desired density, tensile strength, thickness and permeability.
The overall dimensions (x, y and z directions) of the metal matrix sheet material are generally not limited and may be selected based on the specific application in which the seal assembly will be used. In some embodiments, 3 feet by 3 feet sheets of metal matrix sheet material are prepared (with any suitable thickness), and smaller sections are cut from the larger sheets in order to provide the layers of metal matrix sheet material used in the seal assembly.
The upper casing 120a and the lower casing 120b of the casing 120 are generally formed of any suitable metal alloy. Metal alloys are suitable for use because they do not overly restrict the flexibility of the seal assembly while still providing sufficient protection to the metal matrix material layers 110a, 110b, 110c. As discussed above, the sealing assembly 100 shown in
In some embodiments, the casings 120a and 120b are attached to the metal matrix material sheets 110a, 110b, 110c in order to create the final seal assembly 110 and keep the separate metal matrix material sheet layers of the seal assembly 100 together. Any manner of attaching the metal matrix material sheet layers can be used. In some embodiments, the attachment is via a mechanical fastening mechanism, such as a clip or vice. In some embodiments, the attachment is via a welding, fusion, brazing or sintering process. As shown in
The sealing assembly 100 shown in
With reference to
Each metal matrix material layer 320a, 320b is provided within either the top or bottom portion of the S-shaped casing 310 and is retained within the casing 310 by angled end portions 311 of the S-shaped casing 310. In such an embodiment, there may be no requirement for additional securement means, as the assembly stays together by virtue of the metal matrix material layers 320a, 320b being tucked within the upper and lower portion of the S-shaped casing 310 and the angled portion 311 maintaining the metal matrix material layers 320a, 320b within the upper and lower portions of the S-shaped casing.
While not required based on the self-retaining configuration of the embodiment shown in
With reference to
In the embodiment shown in
While not required based on the self-retaining configuration of the embodiment shown in
The seal assemblies shown in
While shown separately from the seal assembly embodiments of
From the foregoing, it will be appreciated that specific embodiments of the invention have been described herein for purposes of illustration, but that various modifications may be made without deviating from the scope of the invention. Accordingly, the invention is not limited except as by the appended claims.
Although the technology has been described in language that is specific to certain structures and materials, it is to be understood that the invention defined in the appended claims is not necessarily limited to the specific structures and materials described. Rather, the specific aspects are described as forms of implementing the claimed invention. Because many embodiments of the invention can be practiced without departing from the spirit and scope of the invention, the invention resides in the claims hereinafter appended.
Unless otherwise indicated, all numbers or expressions, such as those expressing dimensions, physical characteristics, etc., used in the specification (other than the claims) are understood as modified in all instances by the term “approximately”. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the claims, each numerical parameter recited in the specification or claims which is modified by the term “approximately” should at least be construed in light of the number of recited significant digits and by applying rounding techniques. Moreover, all ranges disclosed herein are to be understood to encompass and provide support for claims that recite any and all sub-ranges or any and all individual values subsumed therein. For example, a stated range of 1 to 10 should be considered to include and provide support for claims that recite any and all sub-ranges or individual values that are between and/or inclusive of the minimum value of 1 and the maximum value of 10; that is, all sub-ranges beginning with a minimum value of 1 or more or ending with a maximum value of 10 or less (e.g., 5.5 to 10, 2.34 to 3.56, and so forth) or any values from 1 to 10 (e.g., 3, 5.8, 9.9994, and so forth).
The present application claims priority to U.S. Provisional Application No. 62/518,487, filed Jun. 12, 2017, the entirety of which is hereby incorporated by reference.
Number | Name | Date | Kind |
---|---|---|---|
4645217 | Honeycutt, Jr. | Feb 1987 | A |
5934687 | Bagepalli | Aug 1999 | A |
5997247 | Arraitz | Dec 1999 | A |
7334800 | Minnich | Feb 2008 | B2 |
7360769 | Bennett | Apr 2008 | B2 |
8123232 | Fujimoto | Feb 2012 | B2 |
8678754 | Morgan | Mar 2014 | B2 |
9188228 | Sarawate | Nov 2015 | B2 |
9938844 | Morgan | Apr 2018 | B2 |
10047622 | Sarawate | Aug 2018 | B2 |
10100656 | Bancheri | Oct 2018 | B2 |
10161523 | Sarawate | Dec 2018 | B2 |
20020121744 | Aksit | Sep 2002 | A1 |
20030039542 | Cromer | Feb 2003 | A1 |
20060091617 | Minnich | May 2006 | A1 |
20070158919 | Bennett | Jul 2007 | A1 |
20090026713 | Fujimoto | Jan 2009 | A1 |
20120164429 | Shah | Jun 2012 | A1 |
20130106066 | Sarawate | May 2013 | A1 |
20130108418 | Morgan | May 2013 | A1 |
20130134678 | Sarawate | May 2013 | A1 |
20160215643 | Sarawate | Jul 2016 | A1 |
20170058686 | Bancheri | Mar 2017 | A1 |
Number | Date | Country | |
---|---|---|---|
62518487 | Jun 2017 | US |