RU2790517C2 - Frame with low resistance for filter with pulse purification - Google Patents

Abstract

FIELD: filtration.

SUBSTANCE: invention relates to a frame for a tubular filter sleeve. A support node of a filter frame for a filter with pulse purification contains a set of spaced frame supports, each of which contains a sprocket annular element connected to an inner support ring, wherein the sprocket annular element is formed of a solid strip, wider surfaces of which are oriented essentially parallel to the general direction of a gas flow through the support node of the filter frame. In this case, a width of wider surfaces of the solid strip is at least five times greater than a thickness of thin edges of the specified strip. The sprocket annular element contains a set of radial support shafts formed of the solid strip, adjacently located, and interconnected, wherein a length of each of the specified radial support shafts is 20-40% of a diameter of the inner support ring. The support node also contains a set of frame bars located essentially parallel to each other, wherein each of the specified frame bars is connected to corresponding combined ends of adjacent sprocket annular elements of the set of spaced frame supports.

EFFECT: provision of rigidity and strength of a frame.

6 cl, 11 dwg

Description

PRIORITY DETAILS

[0001] This application claims priority under Australian Provisional Patent Application 2018902484, filed July 9, 2018, which is incorporated herein by reference in its entirety.

FIELD OF TECHNOLOGY

[0002] This invention relates to industrial pulse cleaning filters and, in particular, to improvements to the wire frame or cage for an expanded surface filter bag.

[0003] In particular, the present invention relates to frame supports that are formed from a thin metal plate and have a smaller cross-sectional area relative to the gas flow paths passing through the wire frame.

BACKGROUND OF THE INVENTION

[0004] In industrial gas filtration, pulsed filters are tubular filter bags mounted in wire frames and housed in bag filter chambers containing multiple filters. Dust-laden gas is drawn through the filter bags during the filtration process, and particulate matter is trapped on the outer surface of the filter bag. These filter bags are closed at the bottom and open at the top where the purified gas exits the filters. Periodically, compressed air is sent in a pulsed mode down the bags in the opposite direction with the removal of accumulated dust to remove the accumulated dust residue and clean the filter bags.

[0005] The ratio of the volume flow rate of gas to the working surface of the filter bags, the dust retention, the cleaning efficiency, and the sedimentation of a given filter material determine the efficiency of the bag chamber of a pulsed fabric filter.

[0006] Expanded surface filter bags are used to increase the efficiency of some filter bag chambers by increasing available filtration (reducing the ratio of gas volume flow to filter bag working surface). Known advanced filter technology is presented in US patent applications 5858039, 8187352 B2 or US patent application 20150121822 A1. However, the main limitation of expanded surface filter bags is the overall "length" of the filter frame.

[0007] Expanded filter cages work by maintaining folds in the filter bag. The folds create additional surface area for a given filter diameter. In cross section, such a frame may have an outer perimeter of longitudinal bars and non-circular horizontal supports that extend radially inwards so as to ensure the integrity of the frame and maintain the shape of the pleated filter during operation. These non-circular horizontal supports increase the resistance of the frame itself compared to a conventional round filter bag frame, which can restrict both process gas flow during filtration and reverse pulsed air flow during filter cleaning.

[0008] Prior non-circular horizontal supports that provide structural integrity to an expanded surface filter frame include the use of a horizontal star-shaped support member. In general, the term "star-shaped element" can cover a wide range of connecting parts of the frame, with known examples of wire and extruded metal molds.

[0009] Wire star elements are well known and were the first to be developed. They can be made, for example, from the same wire as the rest of the filter frame and require simple machining. However, there were mechanical limitations when using a wire star. Developments in the art have led to the creation of a stamped metal star.

[0010] The stamped metal star elements may include rays extending from the central sleeve. The sleeve has an opening for more efficient gas flow. The stamped metal star elements are mechanically stable and form a rigid filter. However, all known stamped metal star elements have a significant surface area for the longitudinal (or longitudinal) airflow within the filter bag, and the resulting resistance reduces the efficiency of the filter. The stamped metal star may be in the form of a plate of metal oriented perpendicular to the gas flow, with features pressed into the plate to facilitate attachment to the bars and contribute to stiffness and strength. Stamped metal stars are rigid and can support deep creases. However, the stamped metal star elements of the present invention tend to have aerodynamic drag.

[0011] The purpose of the present invention is to improve the star elements, or at least provide a reasonable alternative to the above prior art.

SUMMARY OF THE INVENTION

[0012] In a first aspect, the present invention relates to a frame for a tubular filter bag with an expanded surface that increases the internal volume of the bag and provides a reduced resistance to the gas flow path through the frame.

[0013] Preferably, the frame for the expanded surface tubular filter bag comprises one or more horizontal frame supports that are connected to the vertical bars of the frame.

[0014] Preferably, the horizontal frame supports are welded to the inside of the vertical frame bars. Most preferably, the horizontal supports of the frame are connected to the inside of the vertical bars of the frame using an automated welding machine.

[0015] Preferably, the frame supports are in the form of stamped metal strips containing a wide body extending between two thin edges. When the frame supports are connected to the vertical bars of the frame, the two thin edges are oriented in the direction of the gas flow path through the frame, thereby providing a reduced resistance to the gas flow path.

[0016] Preferably, the width of the body (W1) is substantially greater than the thickness of the two edges (T1). In one embodiment, the width of the body (W1) is between 5mm and 15mm and the thickness of the two edges (T1) is about 1mm.

[0017] In a preferred embodiment, the present invention relates to a frame for an expanded surface tubular filter bag, comprising:

a plurality of vertical frame bars extending in the longitudinal direction;

at least one horizontal frame support appropriately shaped to support vertical frame bars in a tubular structure; And

wherein the at least one horizontal frame support has a minimum surface area oriented longitudinally with respect to the vertical bars of the frame, thereby maximizing gas flow within the expanded surface filter bag and providing reduced resistance to the horizontal frame support.

[0018] Preferably, the at least one horizontal frame support comprises a multi-pointed stamped metal star-shaped element containing a plurality of radially arranged support beams that are adjacent and connected to each other at the base with an acute angle bend.

[0019] In a preferred embodiment, adjacent arms of the star are connected at the base by an internal support ring.

[0020] Preferably, the length of each beam of the stamped metal star is 20-40 percent of the length of the diameter of the star.

[0021] Preferably, each star tip is connected to a vertical frame bar. Most preferably, each star tip is welded to the inside of the frame's vertical bars. In particular, each point of the star is connected to the inside of the vertical bars of the frame using an automated welding machine.

[0022] Preferably, each beam is formed from adjacent sides that are tapered from a small width at the tip of the star to a greater width at the base.

DESCRIPTION OF GRAPHICS

[0023] Embodiments of the present invention will now be described with reference to the figures.

- In FIG. 1 shows a perspective view of a prior art filter frame for use with an expanded surface filter bag.

- In FIG. 2 shows a perspective view of a frame support in accordance with the teachings of the present technology.

- In FIG. 3 is a plan view of a housing support in accordance with the principles of the present technology, showing the preferred form of attachment to the vertical bars of the frame.

- In FIG. 4 is a plan view of an alternative frame support embodiment showing an alternative form of attachment to the frame vertical bars.

- In FIG. 5 shows a perspective view of a filter frame in accordance with the teachings of the present technology.

- In FIG. 6 is a plan view of an embodiment of a frame support or star in accordance with the teachings of the present technology.

- In FIG. 7 is a side elevational view of the frame support shown in FIG. 6.

- In FIG. 8 is a plan view of a preferred embodiment of a frame support or star in accordance with the teachings of the present technology.

- In FIG. 9 shows a plan view of the frame end support.

- In FIG. 10 is a side elevational view of the frame support or star of FIG. 9.

- In FIG. 11 is a perspective view of a frame for an expanded surface filter bag comprising strip frame supports, an end support, and a tubular bayonet connection.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] As shown in FIG. 1, a prior art pulsed filter wire frame 10 comprises a cylindrical arrangement of longitudinal and generally vertical frame bars 11. In this prior art example, the frame supports 12 are in the form of spaced apart stamped metal star-shaped elements. Usually the supports are welded to each of the frame rods. The wire frame has an inlet 13 at one end and an end portion or bottom 14 at the other end. The frame supports are internal, that is, they are welded to the inner surface of each of the frame bars.

[0025] As shown in FIG. 2-5, the technology of the present invention provides a novel star or frame support 20 for an expanded surface filter bag. Support 20 is made of a thin metal plate that has a much smaller cross-sectional area relative to the gas flow paths (which run in a direction longitudinal to the length of the frame), but even with this reduced cross-sectional area, structural integrity of the frame is still maintained.

[0026] Anvil 20 is in the form of a multi-pointed star containing several support beams 21. Each beam is formed from adjacent sides, which may be tapered, ranging from a small width at the tip of the star to a larger width at the base. Adjacent beams 22, 23 are connected to each other at the base by means of a bend 24. The bend forms an angle called the base angle. In the present technology, the base angle is preferably sharp.

[0027] The radial base length (or "arm length") of the star element 20 is about 20-40 percent of the total diameter of the star element (and hence the filter). Thus, the star-shaped element contains tapered beams to support deep folds. The star-shaped element 20 is stiffened by a band width of 5-15 mm and a nominal thickness of 1 mm. Due to the method of formation of the star-shaped element 20, it has a minimum cross-section with respect to the gas flow, and this applies only to its edges.

[0028] The frame support 20 is preferably made in one piece and is made from a metal strip. Usually it is made of a piece, the ends of which are welded to each other. In this example, the strip is 10 mm wide (W1) and 1 mm thick (T1). In preferred embodiments, each beam 21 is welded at its end to one of the vertical bars 30 of the frame.

[0029] As shown in FIG. 3, the frame support 20 is welded to the inside of the vertical bars 30 of the frame. In FIG. 4 shows an alternative embodiment in which the vertical carcass bars 30 are positioned internally relative to the carcass support 20 and/or are welded to each of the carcass bars. In both embodiments, it is preferred that the frame supports 20 be welded to the frame bars using an automated welding machine, which increases the efficiency of manufacturing the filter cells of the present invention.

[0030] As shown in FIG. 5, the longitudinal or vertical bars 40 of the framework are interconnected by a plurality of spaced apart supports 41 of the framework of the type shown in FIG. 2-4. Preferably, each of the frame supports 41 is welded to the inside of the vertical frame bars 30 (according to FIG. 3). However, in an alternative embodiment, the longitudinal or predominantly vertical bars 43 of the carcass are attached to the inside 42 of the ends of each of the support beams 44 of the carcass. It is this alternative embodiment that is depicted in FIG. 5, but it is preferred that the frame supports 20 be welded to the inside of the vertical frame bars 30 as shown in FIG. 3.

[0031] However, the housing end support 42 is smaller (in diameter) than the other supports 41. This creates a tapered region 45 that simplifies installation of the filter bag.

[0032] As shown in FIG. 5, the direction of gas flow through the filter frame is parallel to the longitudinal length of the bars 40 of the frame. Since the filter cages are usually installed in place in a vertical orientation, the gas flow path can be said to be vertical. It can be seen that each of the frame supports 41 has a respective thin edge (T1) facing in the direction of the vertical gas flow path and its respective wider surface (W1) extends along this direction but has a surface area in the direction perpendicular to the vertical flow path. gas.

[0033] The wider surface (W1) of the frame supports is attached to the bars 40 of the filter frame and thus provides the structural integrity of the filter frame. The thin edge (T1) provides/is a small cross-sectional area in the direction of the vertical gas flow path, thereby minimizing resistance, resulting in much less resistance to gas flow through the filter.

[0034] The support or star frame member 50 of the present invention is depicted in FIG. 6 and 7. In this example, the frame support 50 comprises twelve arms 51. Of course, the support or star frame member 50 of the present invention may comprise any number of arms, and the frame support or star shown in the drawings is merely a typical example. As shown in FIG. 6 and 7, the frame support is made by molding or stamping sheet metal into a star shape. The frame support 50 (W1) is wider than the thickness (T1) of the sheet metal from which it is formed.

[0035] FIG. 8 depicts a more preferred embodiment of the support or star frame member 50, which shows that the frame support further comprises an inner support ring 2. The internal support ring 2 consists of a flat ring of metal plate that provides rigidity and support to the frame support 50.

[0036] An embodiment of the end portion or end of the star frame support member 70 is shown in FIG. 9 and 10. A plurality of supports 91 of the frame body are spaced apart along the longitudinal length of the frame and welded to the longitudinal bars 93 of the frame. In the embodiment depicted in these graphics, the frame longitudinal bars are located within the ends of each of the beams 92. However, as shown in FIG. 3, it is preferred that the frame support 20 be welded to the inside of the frame vertical bars 31.

[0037] The end support 94 is attached to the distal ends 95 of the frame bars. The end support is formed by stamping sheet metal. Each of the beams has a tip or end 96, which can be welded to the rod 93 of the frame. In this example, the frame is formed from two sections 97, 98. The two sections are interconnected by a tubular-type bayonet connection comprising a male part 99 and a female part 100. In this example, the female part is located in the male part and rotates into a removable locking engagement to hold together two frame components 97, 98.

[0038] Although the present invention has been described with reference to specific examples, those skilled in the art will appreciate that the invention may be embodied in many other forms.

[0039] Reference herein to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the present technology. Thus, the use of the phrases "in one embodiment" or "in an embodiment" in various places in this specification does not necessarily refer (although it may refer) to the same embodiment. In addition, specific features, structures, or characteristics may be combined in any suitable manner, as would be apparent to a person skilled in the art from this description, in one or more embodiments.

[0040] In this context, unless otherwise indicated, the use of ordinal numbers "first", "second", "third", etc. to describe a general object simply indicates that different instances of similar objects are mentioned, and does not imply that the objects so described must be arranged in a given sequence in time, space, order, or in any other way.

[0041] In this context, unless otherwise indicated, the use of the terms "longitudinal", "horizontal", "vertical", "left", "right", "above" and "below", as well as their derivative adjectives and adverbs (e.g. "horizontal", "right", "up", etc.) refers to the orientation of the illustrated structure when the particular figure is facing the reader, or referring to the orientation of the structure during normal use, depending on circumstances.

[0042] Although the invention has been described above with reference to preferred embodiments, those skilled in the art will appreciate that it is not limited to these embodiments, but may be embodied in many other forms, variations, and modifications other than those specifically described. The invention includes all such variations and modifications. The invention also includes the steps, features, components and/or devices mentioned or indicated in the description, alone or together, and any possible combinations or any two or more steps or features.

[0043] In this description, unless the context clearly indicates otherwise, the word "comprising" is not intended to have the exclusive meaning of the word, such as "consisting only of", but rather has a non-exclusive meaning in the sense of "comprising at least" . The same, with appropriate grammatical changes, applies to other forms of the word, such as "to contain", etc.

[0044] Other definitions of selected terms used herein can be found in the detailed description of the invention, and they apply throughout the description. Unless otherwise indicated, all other scientific and technical terms used herein have the same meaning as generally understood by a person skilled in the art to which this invention belongs.

[0045] Any forward-looking statements given herein should be understood as referring to certain embodiments of this invention, and not as forward-looking statements given in relation to the invention in all embodiments. If there are forward-looking statements that are considered applicable to all embodiments of this invention, the applicant/patentee reserves the right to subsequently remove them from the description, and he does not rely on these forward-looking statements when accepting or subsequently granting a patent in any country.

INDUSTRIAL APPLICABILITY

[0046] The present invention finds application in industrial gas filtration and, in particular, but not limited to, gas treatment in the electrolysis shop of an aluminum plant.

Claims (8)

1. A filter frame support assembly for a pulsed filter, comprising: a plurality of frame supports spaced apart from each other, each of which contains a star-shaped annular element connected to an internal support ring, and the star-shaped annular element is formed from a single strip, the wider surfaces of which are oriented essentially parallel to the general direction of gas flow through the filter frame support assembly, and the width of the wider surfaces of the solid strip is at least five times the thickness of the thin edges of the specified strip, the star-shaped annular element contains a plurality of radial reference beams formed from a single strip, located next to and connected to each other, and the length of each of these radial reference beams is 20-40% of the diameter of the inner support ring; a plurality of frame bars arranged substantially parallel to each other, each of said frame bars being connected to respective aligned ends of adjacent star-shaped annular members of a plurality of spaced frame supports. 2. The filter frame support assembly of claim 1, wherein the outermost of the wider surfaces of the integral strip is attached to a plurality of frame rods at respective aligned ends of adjacent star-shaped annular members. 3. The support unit of the filter frame according to claim 2, characterized in that the fastening of the wider surfaces of the solid strip to the frame supports spaced apart from each other orients the thin edges of the solid strip of the specified frame supports in the general direction of the gas flow, thereby providing a reduced resistance to gas flow. 4. A filter frame support assembly according to any one of the preceding claims, characterized in that the radial support beams are connected to each other at a base which forms an acute angle. 5. The filter frame support assembly according to claim 4, characterized in that adjacent beams of the star-shaped annular element are connected at the base by means of an internal support ring. 6. The filter frame support assembly according to any one of paragraphs. 4 or 5, characterized in that each of the adjacent beams is formed from adjacent sides, which have a tapered shape, changing from a small width at the ends of the star-shaped annular element to a greater width at the base of the said annular element.

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