Abstract:
A filter assembly system including, a filter bag having an opening, a seal coupled to the filter bag adjacent the opening, wherein the seal comprises a gasket band and a perforated metal band, and the perforated metal band is configured to bias the gasket band in a radial direction into a sealed position upon expansion or contraction of the perforated metal band.

Description:
BACKGROUND OF THE INVENTION 
     The subject matter disclosed herein relates to filter bags. More specifically, the disclosed subject matter relates to filter bags with an adjustable band. 
     Filter bags are used in a variety of equipment and applications, such as intake and exhaust filtration. For instance, a bag house may include multiple filter bags to filter undesirable particulates associated with an industrial system or plant. In particular, the bag house may be equipped with a sufficient number and size of filter bags to filter undesirable particulates from an entire factory, such as a cement factory. Unfortunately, the variety in hole sizes between bag houses and even within bag houses may require many different filter bag sizes to form consistent, dust tight seals. As a result, a custom fit filter bag may be required for a particular bag house. 
     BRIEF DESCRIPTION OF THE INVENTION 
     Certain embodiments commensurate in scope with the originally claimed invention are summarized below. These embodiments are not intended to limit the scope of the claimed invention, but rather these embodiments are intended only to provide a brief summary of possible forms of the invention. Indeed, the invention may encompass a variety of forms that may be similar to or different from the embodiments set forth below. 
     In a first embodiment, a system includes a filter assembly with a filter bag having an opening, and a seal coupled to the filter bag adjacent the opening. The seal may include a gasket band and a perforated metal band. The perforated metal band is configured to bias the gasket band in a radial direction into a sealed position upon expansion or contraction of the perforated metal band. 
     In a second embodiment, a system includes a filter assembly with a filter bag having an opening, and an annular seal coupled to the filter bag around the opening. The annular seal may include a gasket ring generally concentric with a perforated biasing ring. The perforated biasing ring is configured to expand with plastic deformation in a circumferential direction to impart a first radial outward force on the gasket ring, and the gasket ring is configured to expand with elastic deformation in the circumferential direction to impart a second outward radial force toward a sealing interface in response to the first radial outward force. 
     In a third embodiment, a method includes expanding a perforated metal ring of a pulse jet filter bag with plastic deformation in a circumferential direction to impart a first radial outward force, and expanding a gasket ring of the pulse jet filter bag with elastic deformation in the circumferential direction to impart a second outward radial force toward a sealing interface in response to the first radial outward force. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein: 
         FIG. 1  is a cross-sectional side view of an embodiment of a bag house having filter bags with an adjustable band; 
         FIG. 2  is a partial side view of an embodiment of a blowpipe configured to pulse air into a filter bag; 
         FIG. 3  is a partial cutaway perspective view of an embodiment of a filter bag with an adjustable band; 
         FIG. 4  is a partial cutaway perspective view of an embodiment of a filter bag with an adjustable band, illustrating an adjustable band portion within the adjustable band; 
         FIG. 5  is a front view of an embodiment of the adjustable band portion of the adjustable band as illustrated in  FIG. 4 ; 
         FIG. 6  is a front view of an embodiment of the adjustable band portion of the adjustable band as illustrated in  FIG. 4 ; 
         FIG. 7  is a front view of an embodiment of the adjustable band portion of the adjustable band as illustrated in  FIG. 4 ; 
         FIG. 8  is a partial cutaway perspective view of an embodiment of a filter bag with an adjustable band, illustrating a pair of adjustable band portions within the adjustable band; 
         FIG. 9  is a partial perspective view of an embodiment of the pair of adjustable band portions in the adjustable band as illustrated in  FIG. 8 ; 
         FIG. 10  is a cross-sectional view of an embodiment of a filter bag with an adjustable band prior to expansion into a mounting receptacle; 
         FIG. 11  is a cross-sectional view of an embodiment of the filter bag as illustrated in  FIG. 10 , illustrating an expansion tool used to expand the adjustable band into the mounting receptacle; 
         FIG. 12  is a cross-sectional view of an embodiment of the filter bag as illustrated in  FIGS. 10 and 11 , illustrating the adjustable band expanded into the mounting receptacle in response to the expansive force provided by the expansion tool of  FIG. 11 ; 
         FIG. 13  is a cross-sectional view of an embodiment of an internal cage exploded from an interior of the filter bag as illustrated in  FIG. 12 ; 
         FIG. 14  is a cross-sectional view of an embodiment of a filter bag with an adjustable band exploded from an internal mount (e.g., tubing) prior to contraction of the adjustable band about the internal mount; and 
         FIG. 15  is a cross-sectional view of an embodiment of the filter bag as illustrated in  FIG. 14 , illustrating a contraction tool used to contract the adjustable band about the internal mount. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     One or more specific embodiments of the present invention will be described below. In an effort to provide a concise description of these embodiments, all features of an actual implementation may not be described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers&#39; specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure. 
     When introducing elements of various embodiments of the present invention, the articles “a,” “an,” “the,” and “said” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. 
     The present disclosure is directed to a filter bag that includes an adjustable band, such as a perforated metal band or mesh metal band. For example, the adjustable band may include one or more layers of gasket material in combination with one or more perforated metal bands. The filter bags employing the adjustable band may be found in a variety of industries, including food, pharmaceutical, chemical, paint, cement, plastic, alumina, combustion, and steel. Any location that needs filter bags may take advantage of the adjustable band filter bags. While the discussion below focuses on the filtering of gas, the disclosure is not intended to be limited in such a way. The disclosure may be equally applicable to industries that filter liquids. The adjustable band permits installation of a single sized filter bag in a variety of differently sized receptacles or internal mounts (e.g., tubing). For example, a bag house may include multiple locations for attachment of filter bags. Each of these locations, however, may have a slightly different sized hole compared to the other. Thus, a filter bag with an adjustable band enables use of a single size of filter bag rather than various custom sized filter bags, because the adjustable band is expandable and contractible to differently sized receptacles and internal mounts (e.g., tubing). Furthermore, the adjustable band may include an adjustable material that allows the adjustable band to conform to a variety of differently sized holes. In certain embodiments, a tool may be used to conform the adjustable band to differently sized holes in a bag house or other location. The use of an adjustable band on a filter bag may reduce the number of differently sized filter bags needed by bag houses; caused by the variations in tubesheet hole sizes. 
       FIG. 1  is a cross-sectional view of an embodiment of a bag house wherein the filter bags may employ an adjustable band. The bag house  20  may include three sections: an air inlet section  22 , an air cleaning section  24 , and an air outlet section  26 . The air inlet section  22  includes a dirty gas inlet  28 ; baffles  30 ,  32 ,  34 , and  36 ; and a hopper  38 . The air cleaning section  24  includes, filter bags  40 ,  42 ,  44 , and  46 ; tube sheet  48 ; cage covers  50 ,  52 ,  54 , and  56 ; and cages  58  within the filter bags  40 ,  42 ,  44 , and  46 . The air outlet section  26  includes blowpipe  60 , compressed air header  62 , and clean air outlet  64 . 
     The bag house  20  allows dirty air  66  (e.g. air filled with particulates or debris) to enter the air inlet section  22  through the dirty gas inlet  28 . The dirty air  66  after passing through the dirty gas inlet  28  contacts the baffles  30 ,  32 ,  34 , and  36 . The baffles  30 ,  32 ,  34 , and  36  direct the dirty air in a direction towards the clean air outlet  64 . As the dirty air  66  moves in the direction of the clean air outlet  64 , it contacts the filter bags  40 ,  42 ,  44 , and  46  (e.g., fabric filter bags). The filter bags  40 ,  42 ,  44 , and  46  allow air to pass through the bags  40 ,  42 ,  44 , and  46 , while blocking the passage of undesirable particulates. Accordingly, as the dirty air  66  passes through the filter bags  40 ,  42 ,  44 , and  46 , particulates are left on the outside of the bags  40 ,  42 ,  44 , and  46 . The clean air  68  within the filter bags  40 ,  42 ,  44 , and  46  then continues to progress through the filter bags  40 ,  42 ,  44 , and  46  until reaching the outlet section  26 , where the clean air is able to exit through the clean air outlet  64 . 
     The filter bags  40 ,  42 ,  44 , and  46  attach to the air cleaning section  24  with a respective adjustable band. The adjustable bands fit within apertures of the tube sheet  48 . While in the present embodiment, the tube sheet  48  includes four apertures one for each filter bag  40 ,  42 ,  44 , and  46 , it is understood that the tube sheet  48  may include more apertures for example 10 to 100 apertures. The filter bags  40 ,  42 ,  44 , and  46  maintain their shape under the force of the dirty air  66 , because of cages  58  placed into the filter bags  40 ,  42 ,  44 , and  46 . The cages  58  may be made out of materials, such as steel or other metals, hard plastics, etc. that are able to resist deformation under the air pressure of the bag house  20 . The cages  58  maintain the shape of the filter bags  40 ,  42 ,  44 , and  46  under pressure from the dirty air  66  allowing the filter bags  40 ,  42 ,  44 , and  46  to increase air filtration. The cages  58  attach to the cage covers  50 ,  52 ,  54 , and  56 . The cage covers  50 ,  52 ,  54 , and  56  stabilize the filter bags during operation and facilitate insertion and removal of the cage  58  into and from the filter bags, facilitating the filter bag replacement process. 
     The filter bags  40 ,  42 ,  44 , and  46  during use become covered in filtered particulate reducing the filtration ability of the filter bags  40 ,  42 ,  44 , and  46 . This problem is solved by periodically pulse jetting air into the filter bags  40 ,  42 ,  44 , and  46  to knock particulate off the filter bags  40 ,  42 ,  44 , and  46 . As mentioned above, the outlet section  26  includes a blowpipe  60  and a compressed air header  62 . The compressed air header  62  during pulse jet operations pulses compressed air into blowpipe  60 . The blowpipe  60  then directs the pulsed compressed air through openings  70 ,  72 ,  74 , and  76  into the filter bags  40 ,  42 ,  44 , and  46 . The pulses of compressed air shake the filter bags  40 ,  42 ,  44 , and  46  sufficiently to knock particulate loose. The loose particulate may then drop into the hopper  38  of the air inlet section  22 , where it may be removed from the bag house  20 . 
       FIG. 2  is a sectional side view of an embodiment of a blowpipe  60  pulsing air into a filter bag  40 . As discussed above, the air outlet section  26  includes a blowpipe  60  that blows compressed air into the filter bags  40 ,  42 ,  44 , and  46 . The pulsed air from the compressed air header  62  travels through the blowpipe  60  and exits through the blowpipe aperture  70  in the form of air pulses  90 . These air pulses enter the filter bag  40  and cause it to shake, vibrate, etc. sufficiently to knock particulate loose from the outside surface  92  of the filter bag  40 . 
       FIG. 3  is a partial cutaway perspective view of an embodiment of a filter bag  40  with an adjustable band  112 . As more clearly seen in  FIG. 3 , the filter bag  40  connects to the tube sheet  48  around an aperture  110  with the adjustable band  112 . The adjustable band  112  includes a flexible gasket ring/band  114  and an adjustable band portion  116 , which are generally concentric with one another. The gasket ring/band  114  may further define two radial protrusions  118  and  120  and a radial recess  122 . In certain embodiments, the gasket ring/band  114  may made out of an elastomer, rubber, plastic, fabric (e.g., polyester, nomex, acrylic fibers), woven fabrics (made out of fiberglass, polyester, nomex, or similar materials) or another resilient or compressible material, or any combination thereof. In contrast, the adjustable band portion  116  may be made of metal, such as a soft annealed stainless steel, low carbon steel, and aluminum with perforations. For example, the adjustable band portion  116  may have a pattern of uniform or non-uniform openings, such as circular, rectangular, triangular, or mesh-like openings. As discussed in detail below, during installation of the band  112 , the gasket ring/band  114  may undergo elastic deformation while the adjustable band portion  116  (e.g., perforated metal ring) may undergo plastic deformation in a radial direction in response to a tool applied radial force. 
     The filter bag  40  attaches to the tube sheet  48  by fitting the tube sheet edge  124  in-between the two radial protrusions  118  and  120  and within radial recess  122 . As discussed above, bag houses  20  may have multiple apertures that are not equal in size, yet the adjustable band portion  116  can expand or contract to fit the aperture. The adjustable band portion  116 , as will be discussed in more detail below, is capable of expanding outwards or contracting inwards in response to a radial force provided by an installation tool. For example, the perforations of the adjustable band  116  may facilitate the expansion or contraction, while maintaining a considerable radial force for retention after the expansion or contraction. In this manner, the filter bags  40 ,  42 ,  44 , and  46  may accommodate a variety of differently sized apertures. For example, during installation, the adjustable band  116  (e.g., perforated metal biasing ring) is configured to expand with plastic deformation in a circumferential direction to impart a first radial outward force on the gasket ring/band  114 , and the gasket ring/band  114  is configured to expand with elastic deformation in the circumferential direction to impart a second outward radial force toward a sealing interface (e.g., tube sheet edge  124 ) in response to the first radial outward force. 
       FIG. 4  is a partial cutaway perspective view of an embodiment of a filter bag  40  with an adjustable band  138 , illustrating an adjustable band portion  142  within the adjustable band  138 . The adjustable band  138  of  FIG. 4  is similar to  FIG. 3  in that it includes a gasket/ring band  140  and an adjustable band portion  142 . The gasket/ring band  140  defines a front surface  144  and a flat rear surface  146 . The front surface  144  defines two protrusions  148  and  150  that are generally convex in shape. In certain embodiments, the protrusions may not be convex in shape, but may be square-like, triangle-like, etc. The front surface  144  also defines a recess  152  between the two protrusions  148  and  150 . In the present embodiment, the recess  152  is generally concave in shape, but in certain embodiments the recess  152  may be flat, triangle-like, etc. In certain embodiments, the recess  152  may be formed to match the edge of the tube sheet  48  or other location on which the filter bag  40  is positioned. 
     In the present embodiment, the adjustable band portion  142  is between the front face  144  and the rear face  146  of the gasket/ring band  140 . The position of the adjustable band portion  142  behind the front face  144  creates an effective seal on the tube sheet  48  or another location. Thus, the adjustable band portion  142  during adjustment compresses the gasket/ring  140  against the tube sheet  48  or other location creating an airtight seal. The gasket/ring  140  may further define radial air pockets  154  and  156 . These air pockets  154  and  156  may improve the ability of the adjustable band  138  to create an effective airtight seal by wrapping around an edge of a tube sheet  48  or other location. 
     The adjustable band portion  142  may form a ring/band out of a variety of materials, such as metal, plastic, or a combination thereof. In the illustrated embodiment, the adjustable band portion  142  is a perforated metal band made with a dead soft annealed stainless steel (e.g., Rockwell hardness 92-95, Brinell Hardness 201-217). In other embodiments, the adjustable band portion may be made out of a low carbon steel, aluminum, etc. These materials are useful in that they maintain sufficient strength after plastic deformation. This property assists in creating an effective seal for the filter bag  40 , while simultaneously maintaining sufficient strength to withstand the pulse jetting and air filtration in the bag house  20 . 
       FIG. 5  is a front view of an embodiment of the adjustable band portion  142  of the adjustable band  138  as illustrated in  FIG. 4 . The adjustable band portion  142  may be made with a material, thickness, and percentage of perforations to control its ability to expand and contract, while also providing a sufficient radial force for retaining the filter bag  40  after deformation. For example, the adjustable band portion  142  may include a greater number of perforations and a smaller thickness to enable a larger amount of expansion and contraction. By further example, the adjustable band portion  142  may include a lesser number of perforations and a larger thickness to maintain a greater radial force for retention after expansion or contraction. The material selection also may be varied to control the ability to expand or contract the adjustable band portion  142 , the radial retention force after expansion or contraction, and so forth. The embodiment of  FIG. 5  illustrates a metal substrate  169  with perforations  170  that are diamond-like in shape and that form a fence-like pattern, or mesh pattern. The larger the perforations  170  the easier it will be to plastically deform the adjustable band portion  142 , while simultaneously the larger perforations  170  decrease the strength and retention force of the band  142 . In the present embodiment, the perforations  170  are uniform in size and shape as well as distribution, while in other embodiments size, shape, distribution, etc. may vary depending on the design. 
       FIG. 6  is a front view of an embodiment of the adjustable band portion  142  of the adjustable band  138  as illustrated in  FIG. 4 .  FIG. 6  unlike  FIG. 5  illustrates that the perforations may vary in size, shape and distribution over the adjustable band portion  142 . Specifically, the adjustable band portion  142  includes three different sized perforations  180 ,  182 , and  184 . While  FIG. 6  illustrates three differently sized circular perforations, other embodiments may include more or less differently sized perforations of equal or different shapes. Furthermore, while the perforations  180 ,  182 , and  184  are organized into rows, in other embodiments the perforations may be organized in columns that alternate in a pattern or even have no pattern at all. Different perforation sizes and their placement on the adjustable band portion  142  may dictate how it will plastically deform when formed to a specific aperture. For instance, in the present embodiment, the adjustable band portion  142  may plastically deform more easily near a first side  186 , while it may deform less easily near a second side  188 . The band  142  will deform more easily because the perforations  180  are larger and therefore reduce the strength of the band  142  near the first side  186 . 
       FIG. 7  is a front view of an embodiment of the adjustable band portion  142  of the adjustable band  138  as illustrated in  FIG. 4 .  FIG. 7  unlike  FIG. 6  illustrates that the perforations may vary in shape and distribution over the adjustable band portion  142 . Specifically, the adjustable band portion  142  includes three differently shaped perforations  200 ,  202 , and  204 . While in the present embodiment the perforations are diamond-shaped  200 , circular  202 , and rectangular  204 , other embodiments may include other shapes (e.g., oval, rectangular, moon-shaped, oval-shaped, etc.). Other embodiments may include more than the three differently shaped perforations  200 ,  202 , and  204  (e.g., 4 to 10 or more). Furthermore, while the perforations  200 ,  202 , and  204  are organized into rows, in other embodiments the perforations may be organized into columns that alternate in pattern or even have no pattern at all. 
     The differently shaped perforations  200 ,  202 , and  204  and their placement on the adjustable band portion  142  may dictate how it will plastically deform when formed to a specific aperture. For instance, in the present embodiment, the adjustable band portion  142  may plastically deform more easily near a first side  206 , while it may deform less easily near a second side  208 . The band  142  will deform more easily near the first side because the perforations  200  are more numerous and accordingly reduce the strength of the band  142  near the first side  206 . 
       FIG. 8  is a partial cutaway perspective view of an embodiment of a filter bag  40  with an adjustable band  220 , illustrating a pair of adjustable band portions  224  and  226  within the adjustable band  220 . The adjustable band  220  of  FIG. 8  is similar to  FIG. 4  in that it includes a gasket/ring band  222 , but in contrast to  FIG. 4  the adjustable band  220  includes two adjustable band portions  224  and  226 . The gasket/ring band  222  defines a front surface  228  and a flat rear surface  230 . The front surface  228  defines two protrusions  232  and  234  that are generally convex in shape. In certain embodiments, the protrusions  232  and  234  may not be convex in shape, but may be square-like, triangle-like, etc. The front surface  228  also defines a recess  236  between the two protrusions  232  and  234 . In the present embodiment, the recess  236  is generally concave in shape, but in certain embodiments, the recess  236  may be flat, triangle-like, etc. In still other embodiments, the recess  236  may be formed to match the edge of the tube sheet  48  or other location on which the filter bag  40  is positioned. 
     In the present embodiment, the adjustable band portions  224  and  226  are between the front face  228  and the rear face  230  of the gasket/ring band  222 . The position of the adjustable band portions  224  and  226  behind the front face  144  creates an effective seal on the tube sheet  48 . Because the adjustable band portions  224  and  226  are behind the gasket/ring band  222  during installation the adjustable band portions  224  and  226  compresses the gasket/ring  222  against the tube sheet  48  or other location creating an airtight seal. The gasket/ring  222  may further define radial air pockets  238  and  240 . These air pockets  238  and  240  may improve the ability of the adjustable band  220  to create an effective airtight seal, because they cause the gasket/ring band  222  to fold around the edge of the tube sheet  48 . 
     Similar to the adjustable band portion  142  of  FIG. 4 , the adjustable band portions  224  and  226  of  FIG. 8  each may form a ring/band out of a variety of materials, such as metal, plastic, or a combination thereof. In the illustrated embodiment, each adjustable band portion  224  and  226  is a perforated metal band made with a dead soft annealed stainless steel. In still other embodiments, the adjustable band portion  224  and  226  may be made out of aluminum, annealed low carbon steel, etc. These materials are useful in that they maintain sufficient strength after plastic deformation. Furthermore, the adjustable band portions  224  and  226  may have identical or different constructions. For example, the adjustable band portions  224  and  226  may be made with the same or different materials, the same or different thicknesses, the same or different percentage of perforations, the same or different pattern of perforations, or any combination thereof. By further example, one adjustable band portion may be characterized by a greater ductility, higher percentage of perforations, or smaller thickness to enable easier expansion and contraction, while the other adjustable band portion may be characterized by a lower ductility, lower percentage of perforations, or greater thickness to maintain a greater retention force after the expansion or contraction. 
       FIG. 9  is a partial perspective view of an embodiment of the pair of adjustable band portions  224  and  226  in the adjustable band  220  as illustrated in  FIG. 8 . As clearly seen in  FIG. 9 , the band portions  224  and  226  include a variety of different perforations. In the present embodiment, the band portion  224  has diamond like perforations  250  that form a fence-like pattern or uniform mesh. In other embodiments, band portion  224  may include different shaped perforations, patterns, sizes, etc. similar to the discussion with respect to  FIGS. 5-7 . In contrast, the band portion  226  includes perforations  252 ,  254 , and  256  that are circular, diamond, and square shaped, thereby defining a non-uniform arrangement of perforations. Thus, the illustrated embodiment includes bands  224  and  226  of uniform perforations and non-uniform perforations in combination with one another. While each of the perforations  252 ,  254 , and  256  in the band portion  226  differ in shape, they may also differ in size, pattern, etc. similar to the discussion above with respect to  FIGS. 5-7 . Furthermore, the size, pattern, and shape of the perforations  250  on the adjustable band portions  224  and  226  be identical or differ substantially from one another depending on the embodiment. 
       FIG. 10  is a cross-sectional view of an embodiment of a filter bag  270  with an adjustable band  272  prior to expansion into a mounting receptacle or aperture  280 . As discussed above, the adjustable band  272  defines two protrusions  274  and  276  and a recess  278 . In the present embodiment, the filter bag  270  is lowered into an aperture  280  of the tube sheet  48  in the direction of arrow  282 . The filter bag  270  continues in this direction until the recess  278  aligns with the edge  284  of the tube sheet  48 . As discussed above, the alignment of the tube sheet edge  284  with the recess  278  helps create an airtight seal by allowing the protrusions  274  and  276  to wrap around the edge  284 . In this manner, the protrusion  274  contacts the top surface  286 , while the protrusion  276  contacts the bottom surface  288  of the tube sheet  48 , creating a more effective airtight seal. 
       FIG. 11  is a cross-sectional view of an embodiment of the filter bag  270  as illustrated in  FIG. 10 , illustrating an expansion tool system  300  used to expand the adjustable band  272  into the mounting receptacle or aperture  280 . As illustrated in  FIG. 11 , the aperture  280  is larger than the filter bag  270 . Accordingly, the adjustable band  272  is included with the filter bag  270  to enable expansion of the adjustable band  272  into the oversized aperture  280 , thereby creating an airtight seal between the tube sheet  48  and filter bag  270 . After the filter bag  270  has been lowered into the proper position, i.e., the recess  278  is aligned with the edge  284 , the expansion tool system  300  is then used to expand the adjustable band  272  radially outward toward the oversized aperture  280 . 
     Specifically, the system  300  lowers an expansion tool  302  into the filter bag  270  in the direction of arrow  304 . The expansion tool  302  is designed to plastically deform the adjustable band portion(s)  285  within the adjustable band  272 , while elastically deforming the remaining portion (e.g., elastomeric or fabric portion) of the adjustable band  272 . The expansion tool  302  deforms the adjustable band  272  in an outward radial direction as illustrated by the arrows  306 . In this manner, the recess  278  is forced against the tube sheet edge  284  creating an airtight seal. For example, during installation, the adjustable band portion  285  (e.g., perforated metal biasing ring) is configured to expand with plastic deformation in a circumferential direction to impart a first radial outward force on the gasket ring/band  283  (e.g., fiber or elastomeric ring), and the gasket ring/band  283  is configured to expand with elastic deformation in the circumferential direction to impart a second outward radial force toward a sealing interface (e.g., tube sheet edge  284 ) in response to the first radial outward force. Accordingly, the expansion tool  302  may be disposed inside the adjustable band portion  285  (e.g., perforated metal biasing ring), wherein the tool  302  may be actuated to generate a third radial outward force onto the adjustable band portion  285 . 
     In order to expand the expansion tool  302 , the system  300  employs a drive  308  that expands and contracts the expansion tool  302 . For example, in certain embodiments, the expansion tool  302  may axially align the recess  278  with the edge  284 , and then radially expand while maintaining the axial alignment. In other embodiments, the expansion tool  302  may include a tapered shaft (e.g., a conical shaft) or wedge-like tool, which gradually causes radial expansion of the adjustable band  272  during the downward axial movement of the tool  302  in the direction  304 . However, any suitable tool  302  may be used to expand and/or contract the adjustable band  272  to fit differently sized apertures  280 . 
     The expansion tool system  300  may further include a controller  310 . The controller  310  controls the expansion of the expansion tool, preventing it from over expanding or under expanding. For instance, if the expansion tool  302  does not properly expand the adjustable band  272 , the filter bag  270  may fall out or dislodge easily during use. Likewise, overexpansion of the adjustable band  272  may weaken, crack, and/or tear the adjustable band  272 , all of which could lead to premature failure of the filter bag  270 . The controller  310  therefore controls the expansion of the tool  302  until sensing a threshold pressure or retention force, thus, ensuring proper expansion of the adjustable band  272 .  FIG. 12  is a cross-sectional view of an embodiment illustrating an installed filter bag  270 . Upon installation, the filter bag  270  creates an air tight seal  320  with the adjustable band  272  in aperture  280  of the tube sheet  48 . 
       FIG. 13  is a cross-sectional view of an embodiment of a cage system  340  being lowered into the installed filter bag  270  in  FIG. 12 . The cage system  340  includes a cage cover  342  and a cage  344 . The cage cover  342  defines a body  346 , an annular channel  348 , and an annular protrusion or lip  350 . The protrusion  350  further defines an annular contact face  352 . The cage cover  342  and cage  344  join at an interface  354 , wherein the cage cover  342  ends and the cage  344  begins. In the present embodiment, the cage  344  is made out of metal and forms a grid-like pattern. In other embodiments, the cage  344  material may be a plastic grid, a fiber grid, a composite grid, or another cage-like structure of a rigid material. Furthermore, the cage  344  may include a variety of patterns and shapes other than that illustrated in  FIG. 13  (e.g., circular shapes, diamond, rectangular, etc.). 
     As illustrated in  FIG. 13 , the cage system  340  is being lowered into the filter bag  270  in the direction of arrow  356 . As the cage system  340  is lowered, the cage  344  enters and fills out the filter bag  270 . The cage system  340  continues this downward movement until the contact face  352  contacts the top surface  286  of the tube sheet  48 . Thus, the cage cover system  340  rests on the top surface  286  of the tube sheet  48  and the adjustable band  272  fits within the channel  348 . 
       FIG. 14  is a cross-sectional view of an embodiment of a filter bag  370  with an adjustable band  372  exploded from an internal mount (e.g., tube or pipe  382 ) prior to contraction of the adjustable band  372  about the internal mount. The filter bag  370  includes the adjustable band  372 , which contracts rather than expands in order to create an airtight seal. As illustrated, the adjustable band  372  includes an adjustable band portion  373 , which may be a perforated metal band made of a soft annealed stainless steel or another suitable metal. Similar to the discussion above, the adjustable band  372  defines two protrusions  374  and  376  and a recess  378 . In the present embodiment, the filter bag  370  is raised in direction  380  to cover pipe  382 . The filter bag  370  continues in direction  380  until the recess  378  aligns with a protrusion  384  on the pipe  382  (in some embodiments the protrusion may be an annular ring). In the illustrated embodiment, the pipe  382  is undersized relative to the adjustable band  372 , which can be contracted via deformation onto the pipe  382  to create an airtight seal. 
       FIG. 15  illustrates the installation of the filter bag  370  in  FIG. 14  that employs an adjustable band  372 . As illustrated in  FIGS. 14 and 15 , the filter bag  370  is larger than the pipe  382 . Accordingly, the adjustable band  372  is included with the filter bag  370  to enable contraction of the adjustable band  372  about the pipe  382 . Once the filter bag  370  is in the proper position, i.e. the recess  378  is aligned with the protrusion  384 , a tool system  400  contracts the adjustable band  372 . The tool system  400  includes a tool  402 , a drive  404 , and a controller  406 . The tool  402  is designed to plastically deform the adjustable band portion(s)  373 . The tool  402  plastically deforms the adjustable band  372  in an inward radial direction as illustrated by the arrows  408 . In this manner, the recess  378  contacts the protrusion  384  creating an airtight seal. 
     The controller  406  controls the expansion and contraction of the tool  402  through the drive  404 , preventing it from over contracting or under contracting. For instance, if the tool  402  does not properly contract the adjustable band  372 , the filter bag  370  may fall off or dislodge easily during use of the filter bag  370 . Likewise, over contraction of the adjustable band  372  may weaken, crack, or tear the adjustable band  372 , all of which could lead to premature failure of the filter bag  370 . The controller  406  may therefore control the contraction of the tool  402  until sensing threshold pressure or retention force, ensuring proper contraction of the adjustable band  372 . 
     Technical effects of the invention include a filter bag with an adjustable band capable of sealing a range of differently sized holes. Thus, the adjustable band allows for a single size of filter bag to take the place of multiple bag sizes. Furthermore, a tool is included that properly expands or contracts the adjustable band creating a proper seal around the differently sized holes, without damaging the adjustable band or allowing easy dislodgement of the filter bag. In certain embodiments, the adjustable band includes an adjustable band portion made of a perforated metal, such as a dead soft annealed stainless steel, annealed low carbon steel, or aluminum. 
     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.