The subject matter disclosed herein relates to turbo-machines (e.g., gas and/or steam turbines) and, in particular, to filter devices that remove particulates from fluids flowing into the turbo-machine.
Power generating systems may use turbo-machines to drive a generator. During normal operation, the turbo-machines draw in air for combustion. The air passes through a compressor before a combustor mixes the air with fuel and ignites the mixture to drive a turbine.
Contaminants (e.g., dirt, dust, and salt) in the air can reduce performance and efficiency of the turbo-machine. These contaminants can corrode the surface of the compressor blades. The resulting surface roughness decreases air flow and efficiency and, ultimately, reduces both the output of the turbo-machine and the efficiency of the power generating system overall.
Filtration systems remove particulates from the air to prevent damage the contaminants can cause to the turbo-machine. Examples of these filtration systems may feature a filter device upstream of the compressor. The filter device comprises a filter media to capture particulates before the particulates can reach the combustor. Conventional filter devices often have an elongated body, which secures to a wall, or “tubesheet,” found in the filtration system. A seal is disposed between the tubesheet and wall. This seal prevents unfiltered air from bypassing the filter cartridge, which can permit contaminants to pass through the tubesheet with air that transits the power generating system and to the turbo-machine.
During long periods of operation, particulates may saturate the filter media, which results in a condition that impedes the flow of air and can exacerbate pressure drop across the filter media. The excess particulates may also increase the weight of the filter device. In some cases, the additional weight on the elongated body can cause the filter device to sag, thereby pulling the seal away from the tubesheet and allowing air to flow between the tubesheet and the seal.
The discussion above is merely provided for general background information and is not intended to be used as an aid in determining the scope of the claimed subject matter.
This disclosure describes examples of a filter device with a seal element that can prevent leaks that occur due to sagging and/or displacement of a filter device from the tubesheet in a power generating system. The seal element can have a non-uniform profile that defines a material thickness for the seal element. In one example, the non-uniform profile defines an area or section of the seal element that is thicker relative to other areas or sections of the seal element. The thicker area corresponds to certain positions on the filter device that are susceptible to movement that can occur, e.g., due to particulate build-up during operation of the turbo-machine.
This disclosure describes, in one embodiment, a filter device that comprises an elongated body comprising a filter media and a seal element disposed on a first end of the elongated body. The seal element has a non-uniform profile that defines a material thickness for the seal element. The material thickness can comprise a first material thickness in a first section of the seal element and a second material thickness in a second section of the seal element, wherein the first material thickness is greater than the second material thickness.
This disclosure also describes, in one embodiment, a filter device that comprises a first filter element having a first end and a second end, a second filter element abutting the second end of the first filter element, and a seal element disposed on the first end of the first filter element. The seal element has a first material thickness in a first section and a second material thickness in a second section, wherein the first material thickness is greater than the second material thickness.
This disclosure further describes, in one embodiment, a power generating system that comprises an air filter unit with a tubesheet, a filter device secured to the tubesheet, and a seal element disposed between the filter device and the tubesheet. The seal element has a first material thickness in a first section of the seal element and a second material thickness in a second section of the seal element, wherein the first material thickness is greater than the second material thickness.
This brief description of the invention is intended only to provide a brief overview of the subject matter disclosed herein according to one or more illustrative embodiments, and does not serve as a guide to interpreting the claims or to define or limit the scope of the invention, which is defined only by the appended claims. This brief description is provided to introduce an illustrative selection of concepts in a simplified form that are further described below in the detailed description. This brief description is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. The claimed subject matter is not limited to implementations that solve any or all disadvantages noted in the background.
So that the manner in which the features of the invention can be understood, a detailed description of the invention may be had by reference to certain embodiments, some of which are illustrated in the accompanying drawings. It is to be noted, however, that the drawings illustrate only certain embodiments of this invention and are therefore not to be considered limiting of its scope, for the scope of the invention encompasses other equally effective embodiments. The drawings are not necessarily to scale, emphasis generally being placed upon illustrating the features of certain embodiments of the invention. In the drawings, like numerals are used to indicate like parts throughout the various views. Thus, for further understanding of the invention, reference can be made to the following detailed description, read in connection with the drawings in which:
Broadly, this disclosure sets forth various embodiments of a filter device found in a power generating system, e.g., with a turbo-machine. Examples of the filter device include cartridge filters, which have an elongated body that anchors at one end to a wall member found in the structure of the power generating system. The other end of the elongated body remains essentially unsupported.
As discussed more below, these filter devices maintain an effective airtight seal between the elongated body and the wall member. This airtight seal prevents air from bypassing the filter device, which can introduce contaminants into the turbo-machine that are detrimental to performance and longevity of the power generating system. In one aspect, the filter device can include a seal element that forms the airtight seal at the end of the elongated body that anchors to the wall member. The seal element often resides between a face of the elongated body and the wall member.
To maintain the airtight seal during extended operation of the turbo-machine, examples of the seal element have a non-uniform profile, the design of which compensates for forces that tend to cause the filter device to disengage from the wall member. These forces include, for example, cantilever forces that result from the build-up of particulates in the filter device. This build-up increases the weight of the elongated body and, thus, increases the magnitude of the moment forces pulling on the anchored end of the filter device. Eventually, these moment forces can displace the anchored end of filter device from the wall member, often resulting in gaps between the filter device and the wall member that allow air to flow between the filter device and the wall member. Use of the seal element with the non-uniform profile, however, maintains contact between the filter device and the wall despite the natural “sag” of the filter device that can occur during operation of the turbo-machine.
Examples of the seal element can comprise various compressible materials, e.g., polymer-based materials and/or other materials that are typical of gaskets and o-rings to form the air tight seal. These materials can be formed into separate elements, which secure onto the structure of the filter device 100. Construction of the filter device 100 can likewise incorporate such compressible materials. In this way, the seal element 126 can be formed as an integral and/or partially integral component of the filter device 100.
As best shown in
The extent of variation in the material thickness 130 (e.g., between the first material thickness 136 and the second material thickness 138) can depend on various factors determinative of where gaps and leaks may form, e.g., dimensions of the elongated body (e.g., elongated body 102 of
In one embodiment, the elongated body 102 also includes an orientation feature 148 to aligns the elongated body 102 with the mounting structure 112. Examples of the orientation feature 148 include grooves, detents, and notches, which can receive a portion of the mounting structure 112. These features prevent rotation of the elongated body 102 with respect to the mounting structure 112 during installation. Moreover, use of the orientation feature 148 can ensure that the elongated body 102 properly compresses the seal element 126 against the tubesheet (e.g., tubesheet 122 of
The material thickness (e.g., material thickness 130 of
In connection with the present discussion, for example, the annular ring 140 can have a first material thickness (e.g., first material thickness 136 of
In
The turbo-machine 208 can include a compressor 220, a combustor 222, and a turbine 224 (e.g., a gas or steam turbine). During operation, the compressor 220 draws air (e.g., fluid F) into the air filter unit 206. The air passes through the filter device 200 and the tubesheet 218 before the air enters the turbo-machine 208. The compressor 220 pressurizes the air, which is subsequently fed to the combustor 222 to mix the air with fuel and ignite the mixture to provide the driving force for the turbine 224.
Examples of the filter device 200 can have a two element filter set (e.g., a first filter element 226 and an second filter element 228). The first filter element 226 and the second filter element 228 can comprise filter media that allows the collection of particulates on its surface. Exemplary filter media includes fabric filter media, although this disclosure also contemplates materials, e.g., closed cell foams, with properties sufficient to trap particulates without causing undue pressure drop during operation of the turbo-machine. In one example, the filter media has pleats and/or folds distributed throughout the structure of the first filter element 226 and the second filter element 228 to increase the surface area available to capture and hold particulates.
Examples of the first filter element 226 and the second filter element 228 can abut one another, as shown in
The filter device 200 can also include a mounting element that provides an interface to mount and secure the filter device 200, e.g., to the tubesheet 218 of air filter unit 206. The mounting element couples with tubesheet 218 to support the filter device 200 in the mounted configuration (e.g., the proper mounted configuration of
One or more of the elements of the mounting element can be formed monolithically, as a single integrated structure. In other alternatives, the elements can comprise separate pieces that are assembled together using known fasteners and techniques. Construction of the mounting element can use metals, plastics, composites, and other materials compatible, e.g., with the filter media. Generally, suitable materials having mechanical properties to support the weight of the filter device 200 in the mounted configuration and/or to reduce the extent to which the filter device 200 will sag due to particulate build-up.
As used herein, an element or function recited in the singular and proceeded with the word “a” or “an” should be understood as not excluding plural said elements or functions, unless such exclusion is explicitly recited. Furthermore, references to “one embodiment” of the claimed invention should not be interpreted as excluding the existence of additional embodiments that also incorporate the recited features.
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 language of the claims.