Expansion drum tubular filter

Abstract

A filter bag floating fixing structure is arranged at each large-diameter position of a cage frame, each filter bag floating fixing structure comprises a floating component and a fixing component, each floating component comprises a radial floating part which is fixed on the cage frame in a radial floating manner and is provided with a floating cambered surface attached to the inner circumference of a filter bag, and the fixing component is fixed on the cage frame in a radial floating manner. The radial floating piece moves in the radial direction relative to the horizontal center of the cage frame under the action of the internal and external pressure difference of the filter bag, the fixing assembly comprises an expansion and shrinkage clamping ring surrounding the periphery of the filter bag, and the expansion and shrinkage clamping ring is provided with a limiting cambered surface which is attached to the periphery of the filter bag so that the filter bag can be tightly attached to the floating cambered surface; the limiting cambered surface expands and shrinks in the radial direction under the action of the radial floating piece. According to the device, the filter bag is clamped between the floating cambered surface and the limiting cambered surface, the filter bag generates micro radial displacement during expansion and shrinkage, the cyclic tensile stress is eliminated, the fixed point of the filter bag is not rigidly constrained any more, and the fatigue life of the filter bag is prolonged.

Description

Technical Field

[0001] This utility model relates to the field of filter technology, specifically to an expansion drum tubular filter. Background Technology

[0002] For example, the Chinese invention patent with authorization announcement number CN1320940C discloses an expansion drum tubular filter, which is a conventional expansion drum tubular filter. Its support frame is designed as a corrugated cage frame, and a filter bag fixing groove is provided at the large diameter of the cage frame. The filter bag is fixed to the fixing groove in sections by strapping or clamps. During backwashing, this structure uses fluid pressure to expand the filter bag into multiple drum shapes, causing the filter cake to break and fall off, and expanding the filter micropores, which significantly improves the backwashing effect.

[0003] However, during long-term use, the filter bags in the above-mentioned structures repeatedly expand and contract during filtration and backwashing. Because the filter bags and the fixing tank are rigidly fixed, the filter bags are subjected to severe cyclic tensile and shear stress at the fixing point. This causes fatigue cracks to first appear near the fixing point and gradually tear, resulting in a generally short filter bag lifespan. Frequent downtime for filter bag replacement not only increases operating costs but also reduces production efficiency.

[0004] Therefore, how to improve the stress state of the filter bag fixing points and extend the filter bag life without changing the original corrugated support frame structure is a technical problem that urgently needs to be solved in this field. Utility Model Content

[0005] The purpose of this invention is to overcome the shortcomings and deficiencies of the existing technology and to provide a drum-type tubular filter.

[0006] The technical solution adopted by this utility model is as follows: A tubular filter with an expanding drum shape includes a tank, several support frames, and filter bags fitted over each support frame. A tube plate is fixed inside the tank, dividing the tank into a clear liquid tank and a filtration tank. The clear liquid tank is located above the filtration tank. The tube plate has several holes. The support frames are located inside the filtration tank and installed in the holes. The support frames are corrugated cages composed of multiple regular conical or arc-shaped sections.

[0007] The cage frame is equipped with filter bag floating and fixing structures at each of its large diameter points. The filter bag floating and fixing structures include floating components and fixing components. The floating components include radially floating members that are radially floating and fixed to the cage frame and have floating arc surfaces that conform to the inner circumference of the filter bags. The radially floating members move radially relative to the horizontal center of the cage frame under the action of the pressure difference between the inside and outside of the filter bags.

[0008] The fixing component includes an expansion and contraction retaining ring surrounding the outer periphery of the filter bag. The expansion and contraction retaining ring has a limiting arc surface that fits against the outer periphery of the filter bag to make the filter bag adhere tightly to the floating arc surface. The limiting arc surface expands and contracts radially under the action of the radial floating component.

[0009] Preferably, the floating assembly further includes a first elastic element and a first limiting element, and the radial floating element includes an arc-shaped plate portion and a floating rod portion fixed to the center of the concave surface of the arc-shaped plate portion, wherein the floating arc surface is located on the convex surface of the arc-shaped plate portion.

[0010] The cage frame has a first through hole with a diameter larger than that of the floating rod at its circumferential position. The end of the floating rod away from the arc-shaped plate passes through the first through hole from the outside to the inside and is fixedly connected to the first limiting member. The first limiting member is larger than the first through hole and restricts the radial floating member from disengaging from the first through hole.

[0011] The first elastic element is sleeved outside the end of the floating rod that protrudes through the first through hole, and its two ends are respectively connected to the concave surface of the arc-shaped plate and the first limiting element.

[0012] Preferably, the cage has at least two sets of floating components evenly distributed around its circumference at each of its large diameters.

[0013] Preferably, the floating arc surface is provided with a plurality of protrusions.

[0014] Preferably, the end of the floating rod that extends through the first through hole is provided with an external thread, and the first limiting member is threadedly connected to the floating rod.

[0015] Preferably, the upper and lower ends of the outer convex surface of the arc-shaped plate are rounded.

[0016] Preferably, the expansion and contraction retaining ring includes a first semi-ring portion and a second semi-ring portion disposed opposite to each other. The first semi-ring portion has a first fixing plate portion at both ends, and the second semi-ring portion has a second fixing plate portion at both ends. The first fixing plate portion and the second fixing plate portion are disposed parallel to each other. The second fixing plate portion has a second through hole along the concave surface of the second semi-ring portion.

[0017] The fixing assembly further includes a fixing rod, a second elastic element, and a second limiting element. The diameter of the fixing rod is smaller than that of the second through hole. One end of the fixing rod is fixedly connected to the first fixing plate, and the other end passes through the second through hole and is fixedly connected to the second limiting element. The second limiting element is larger than that of the second through hole and restricts the fixing rod from disengaging from the first and second through holes. The second elastic element is sleeved on the end of the fixing rod that passes through the second through hole, and its two ends are respectively connected to the second fixing plate and the second limiting element.

[0018] Preferably, the end of the fixing rod that extends through the second through hole is provided with an external thread, and the second limiting member is threadedly connected to the fixing rod.

[0019] Preferably, the first fixing plate portion has a threaded hole corresponding to the second through hole, and the fixing rod is threadedly connected to the threaded hole.

[0020] The beneficial effects of this utility model are as follows: In this device, the filter bag is clamped between the floating arc surface and the limiting arc surface. When the filter bag expands and contracts, it undergoes a slight radial displacement, eliminating cyclic tensile stress. The fixing point of the filter bag is no longer a rigid constraint, thus extending the fatigue life of the filter bag. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, obtaining other drawings based on these drawings without creative effort still falls within the scope of this utility model.

[0022] Figure 1 This is a front view of the filtering state in an embodiment of the present invention;

[0023] Figure 2 This is a front view of the recoil state in an embodiment of the present invention;

[0024] Figure 3 This is a top view of the filtering state in an embodiment of the present invention;

[0025] Figure 4 for Figure 1 Enlarged view of the structure at point A in the middle;

[0026] Figure 5 for Figure 2 Enlarged view of the structure at point B in the middle;

[0027] Figure 6 for Figure 4 Enlarged view of the structure at point C;

[0028] Figure 7 for Figure 5 Enlarged view of the structure at point D;

[0029] Figure 8 for Figure 3 Enlarged view of the structure at point E in the middle;

[0030] In the diagram, 1 is the tank body; 2 is the support frame; 3 is the filter bag; 4 is the tube sheet; 11 is the clear liquid tank; 12 is the filter tank; 21 is the first perforation; 51 is the radial floating component; 52 is the first elastic component; 53 is the first limiting component; 61 is the expansion and contraction retaining ring; 62 is the fixing rod; 63 is the second elastic component; 64 is the second limiting component; 511 is the arc-shaped plate; 512 is the floating rod; 513 is the protrusion; 611 is the first semi-ring; 612 is the second semi-ring; 613 is the first fixing plate; 614 is the second fixing plate; 5111 is the floating arc surface; 6111 is the limiting arc surface; 6131 is the threaded hole; and 6141 is the second perforation. Detailed Implementation

[0031] To make the objectives, technical solutions and advantages of this utility model clearer, the utility model will be described in further detail below with reference to the accompanying drawings.

[0032] It should be noted that all uses of "first" and "second" in the embodiments of this utility model are for the purpose of distinguishing two entities or parameters with the same name but different names. It is clear that "first" and "second" are only for the convenience of expression and should not be construed as limiting the embodiments of this utility model. Subsequent embodiments will not explain this in detail.

[0033] The directional and positional terms used in this utility model, such as "up," "down," "front," "back," "left," "right," "inner," "outer," "top," "bottom," and "side," are merely for reference to the accompanying drawings. Therefore, the directional and positional terms used are for the purpose of explaining and understanding this utility model, and not for limiting the scope of protection of this utility model.

[0034] like Figures 1 to 8 As shown in the illustration, an expansion-drum tubular filter according to an embodiment of this utility model includes a tank 1, several support frames 2, and filter bags 3 fitted over each support frame 2. A tube plate 4 is fixed inside the tank 1, dividing the tank 1 vertically into a clear liquid tank 11 and a filter tank 12. The clear liquid tank 11 is located above the filter tank 12. The tube plate 4 has several holes. The support frames 2 are located inside the filter tank 12 and installed in the holes. The support frames 2 are corrugated cages composed of multiple regular conical or arc-shaped sections.

[0035] The cage frame is equipped with a filter bag floating and fixing structure at each of its large diameters. The filter bag floating and fixing structure includes a floating component and a fixing component. The floating component includes a radially floating member 51 that is radially floating and fixed to the cage frame and has a floating arc surface 5111 that fits the inner circumference of the filter bag 3. The radially floating member 51 moves radially relative to the horizontal center of the cage frame under the action of the pressure difference between the inside and outside of the filter bag 3.

[0036] The fixing component includes an expansion and contraction retaining ring 61 surrounding the outer periphery of the filter bag 3. The expansion and contraction retaining ring 61 has a limiting arc surface 6111 that fits against the outer periphery of the filter bag 3 so that the filter bag 3 is pressed tightly against the floating arc surface 5111. The limiting arc surface 6111 expands and contracts radially under the action of the radial floating member 51.

[0037] The tank 1 has a first inlet and outlet 111 connected to the clear liquid tank 11, a filter material inlet 121 connected to the filter tank 12, and a slag discharge port 122 located at the bottom of the tank 1 and connected to the filter tank 12. In this embodiment, the first inlet and outlet serve as both the clear liquid outlet and the backflushing liquid inlet. Alternatively, an additional port connected to the clear liquid tank can be provided to make the clear liquid outlet and the backflushing liquid inlet independent.

[0038] like Figure 1 and Figure 3 The diagram shows the operating state of this device during filtration. With the slag discharge port closed and the first inlet / outlet and the filter material inlet open, the filter material enters the filter tank through the filter material inlet. The fluid force of the filter material compresses the filter bag, and the material passes through the filter bag for filtration. The clear liquid enters the clear liquid tank and exits through the first inlet / outlet. Some of the solid residue from the filtered material gradually accumulates on the outer surface of the filter bag. Simultaneously, the radial floating component moves radially towards the horizontal center of the cage under the action of fluid force, and the expansion and contraction retaining ring contracts to its minimum diameter. When the thickness of the residue accumulated on the outer surface of the filter bag reaches the operating set value, backwashing can be performed according to the operating pressure set at the filter material inlet.

[0039] like Figure 2 The diagram shows the working state of this device during backflushing. The inlet of the material to be filtered is closed, and the first inlet and outlet and the slag discharge port are opened. The backflushing liquid flows from the clear liquid tank through the filter bag to the slag discharge port. The fluid force of the backflushing liquid expands the filter bag into multiple drum shapes, causing the geometric cavity of the solid slag bonding layer to be crushed into fragments and fall off. The filter bag's micropores expand, allowing the filter micropores to be thoroughly cleaned. At the same time, the radial floating component moves radially away from the horizontal center of the cage under the action of fluid force. The expansion and contraction retaining ring expands to its maximum diameter. During this process, the filter bag is clamped between the floating arc surface and the limiting arc surface. The filter bag undergoes a small radial displacement during expansion and contraction, eliminating cyclic tensile stress. The fixed point of the filter bag is no longer a rigid constraint, and the fatigue life of the filter bag is extended.

[0040] The floating assembly further includes a first elastic element 52 and a first limiting element 53. The radial floating element 51 includes an arc-shaped plate portion 511 and a floating rod portion 512 fixed to the center of the concave surface of the arc-shaped plate portion 511. The floating arc surface 5111 is located on the convex surface of the arc-shaped plate portion 511.

[0041] The cage frame has a first through hole 21 with a diameter larger than that of the floating rod portion 512, which is radially penetrating at its circumferential position. The end of the floating rod portion 512 away from the arc-shaped plate portion 511 passes through the first through hole 21 from the outside to the inside and is fixedly connected to the first limiting member 53. The first limiting member 53 is larger than the first through hole 21 and restricts the radial floating member 51 from disengaging from the first through hole 21.

[0042] The first elastic member 52 is sleeved on the end of the floating rod portion 512 that protrudes from the first through hole 21, and its two ends are respectively connected to the concave surface of the arc plate portion 511 and the first limiting member 53.

[0043] This design effectively improves the stability of the radial floating component's radial movement. During filtration, fluid force is applied to the outer periphery of the filter bag and transmitted radially to the radial floating component. Since the fluid force is greater than the restoring force of the first elastic component, the radial floating component compresses the first elastic component, causing it to move smoothly towards the horizontal center of the cage. During backflush, the radial floating component, under the influence of fluid force and the restoring force of the first elastic component, moves smoothly radially away from the horizontal center of the cage. In this embodiment, the first elastic component is specifically a spring.

[0044] The cage has at least two sets of floating components evenly distributed around its circumference at each of its major diameters.

[0045] This design ensures the uniformity of minute radial displacement of the filter bag during expansion and contraction. In this embodiment, four sets of floating components are specifically installed at the same height.

[0046] The floating arc surface 5111 is provided with a number of protrusions 513.

[0047] This design effectively increases the relative movement resistance between the filter bag and the floating arc surface, making it less likely for the floating arc surface and the filter bag to move relative to each other in the axial direction, thereby improving the stability of the fit between the inner circumference of the filter bag and the floating arc surface.

[0048] The floating rod portion 512 has an external thread at least at the end that extends through the first through hole 21, and the first limiting member 53 is threadedly connected to the floating rod portion 512.

[0049] This design improves the ease of assembling and disassembling the floating component. At the same time, the elastic potential energy of the first elastic component can be adjusted by adjusting the threaded connection position between the first limiting component and the floating rod, thereby limiting the radial displacement of the radial floating component.

[0050] like Figure 6 and Figure 7 As shown, the upper and lower ends of the outer convex surface of the arc-shaped plate portion 511 are rounded.

[0051] This design further avoids stress concentration when the curved plate meets the filter bag, compared to a right-angle transition.

[0052] The expansion and contraction retaining ring 61 includes a first semi-ring portion 611 and a second semi-ring portion 612 disposed opposite to each other. The first semi-ring portion 611 has a first fixing plate portion 613 at both ends, and the second semi-ring portion 612 has a second fixing plate portion 614 at both ends. The first fixing plate portion 613 and the second fixing plate portion 614 are disposed parallel to each other. The second fixing plate portion 614 has a second through hole 6141 extending through the concave surface of the second semi-ring portion 612.

[0053] The fixing assembly further includes a fixing rod 62, a second elastic element 63, and a second limiting element 64. The diameter of the fixing rod 62 is smaller than that of the second through hole 6141. One end of the fixing rod 62 is fixedly connected to the first fixing plate portion 613, and the other end of the fixing rod 62 passes through the second through hole 6141 and is fixedly connected to the second limiting element 64. The second limiting element 64 is larger than that of the second through hole 6141 and restricts the fixing rod 62 from disengaging from the first and second through holes 6141. The second elastic element 63 is sleeved on the end of the fixing rod 62 that passes through the second through hole 6141, and its two ends are respectively connected to the second fixing plate portion 614 and the second limiting element 64.

[0054] This design effectively improves the stability of the expansion and contraction of the retaining ring, ensuring that the retaining ring remains tightly attached to the outer periphery of the filter bag during filtration and backwashing.

[0055] The end of the fixing rod 62 that extends through the second through hole 6141 is provided with an external thread, and the second limiting member 64 is threadedly connected to the fixing rod 62.

[0056] This design improves the ease of assembling and disassembling the fixing components. At the same time, the elastic potential energy of the second elastic element can be adjusted by adjusting the threaded connection position between the second limiting element and the fixing rod, thereby controlling the expansion and contraction limit of the expansion and contraction retaining ring.

[0057] The first fixing plate 613 has a threaded hole 6131 through the second through hole 6141, and the fixing rod 62 is threadedly connected to the threaded hole 6131.

[0058] This design further improves the ease of assembling and disassembling the fixing components. Specifically, the fixing rod is the shank of the screw, with its tail end passing through the threaded hole and the second through hole in sequence, and its head located outside the threaded hole to form a limit.

[0059] The above-disclosed embodiments are merely preferred embodiments of the present utility model and should not be construed as limiting the scope of the present utility model. Therefore, any equivalent variations made in accordance with the claims of the present utility model shall still fall within the scope of the present utility model.

Claims

1. A tubular filter with an expanding drum, comprising a tank (1), several support frames (2), and filter bags (3) fitted over each support frame (2), wherein a tube plate (4) is fixed inside the tank (1) to divide the tank (1) into a clear liquid tank (11) and a filter tank (12), the clear liquid tank (11) being located above the filter tank (12), the tube plate (4) having several holes, the support frames (2) being located inside the filter tank (12) and installed on the holes, the support frame (2) being a corrugated cage frame composed of multiple regular conical or arc-shaped sections, characterized in that: The cage frame is equipped with a filter bag floating and fixing structure at each of its large diameters. The filter bag floating and fixing structure includes a floating component and a fixing component. The floating component includes a radial floating member (51) that is radially floating and fixed on the cage frame and has a floating arc surface (5111) that fits the inner circumference of the filter bag (3). The radial floating member (51) moves radially relative to the horizontal center of the cage frame under the action of the pressure difference between the inside and outside of the filter bag (3). The fixing component includes an expansion and contraction retaining ring (61) surrounding the outer periphery of the filter bag (3). The expansion and contraction retaining ring (61) has a limiting arc surface (6111) that fits against the outer periphery of the filter bag (3) so that the filter bag (3) is pressed against the floating arc surface (5111). The limiting arc surface (6111) expands and contracts radially under the action of the radial floating member (51).

2. The expandable tube filter according to claim 1, characterized in that: The floating component also includes a first elastic element (52) and a first limiting element (53). The radial floating member (51) includes an arc-shaped plate portion (511) and a floating rod portion (512) fixed to the center of the concave surface of the arc-shaped plate portion (511). The floating arc surface (5111) is located on the convex surface of the arc-shaped plate portion (511). The cage has a first through hole (21) with a diameter larger than that of the floating rod (512) in the circumferential position. The end of the floating rod (512) away from the arc plate (511) passes through the first through hole (21) from the outside to the inside and is fixedly connected to the first limiting member (53). The first limiting member (53) is larger than the first through hole (21) and restricts the radial floating member (51) from disengaging from the first through hole (21). The first elastic member (52) is sleeved on the end of the floating rod part (512) that passes through the first through hole (21) and its two ends are respectively connected to the concave surface of the arc plate part (511) and the first limiting member (53).

3. A tubular filter with an expanding drum according to claim 1 or 2, characterized in that: The cage has at least two sets of floating components evenly distributed around its circumference at each of its large diameters.

4. A tubular filter with an expanding drum according to claim 1 or 2, characterized in that: The floating arc surface (5111) is provided with a number of protrusions (513).

5. A tubular filter with an expanding drum according to claim 2, characterized in that: The floating rod (512) has an external thread at least at the end that passes through the first through hole (21), and the first limiting member (53) is threadedly connected to the floating rod (512).

6. A tubular filter with an expanding drum according to claim 2, characterized in that: The upper and lower ends of the outer convex surface of the arc-shaped plate (511) are rounded.

7. A tubular filter with an expanding drum according to claim 1, characterized in that: The expansion and contraction retaining ring (61) includes a first semi-ring portion (611) and a second semi-ring portion (612) arranged opposite to each other. The first semi-ring portion (611) has a first fixing plate portion (613) at both ends, and the second semi-ring portion (612) has a second fixing plate portion (614) at both ends. The first fixing plate portion (613) and the second fixing plate portion (614) are arranged parallel to each other. The second fixing plate portion (614) has a second through hole (6141) along the concave surface of the second semi-ring portion (612). The fixing assembly further includes a fixing rod (62), a second elastic element (63), and a second limiting element (64). The diameter of the fixing rod (62) is smaller than that of the second through hole (6141). One end of the fixing rod is fixedly connected to the first fixing plate (613), and the other end passes through the second through hole (6141) and is fixedly connected to the second limiting element (64). The second limiting element (64) is larger than that of the second through hole (6141) and restricts the fixing rod (62) from disengaging from the first and second through holes (6141). The second elastic element (63) is sleeved on the end of the fixing rod (62) that passes through the second through hole (6141), and its two ends are respectively connected to the second fixing plate (614) and the second limiting element (64).

8. A tubular filter with an expanding drum according to claim 7, characterized in that: The end of the fixing rod (62) that extends through the second through hole (6141) is provided with an external thread, and the second limiting member (64) is threadedly connected to the fixing rod (62).

9. A tubular filter with an expanding drum according to claim 7, characterized in that: The first fixing plate (613) has a threaded hole (6131) through the second through hole (6141), and the fixing rod (62) is threadedly connected to the threaded hole (6131).

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