CN108159756B

CN108159756B - Detention basket and filter disc thereof

Info

Publication number: CN108159756B
Application number: CN201711446876.9A
Authority: CN
Inventors: 石亮; 于江; 王超; 魏家炜; 颜昌彪; 熊国栋; 邵小; 李向阳
Original assignee: China General Nuclear Power Corp; China Nuclear Power Technology Research Institute Co Ltd; CGN Power Co Ltd
Current assignee: China General Nuclear Power Corp; China Nuclear Power Technology Research Institute Co Ltd; CGN Power Co Ltd
Priority date: 2017-12-27
Filing date: 2017-12-27
Publication date: 2021-06-08
Anticipated expiration: 2037-12-27
Also published as: CN108159756A

Abstract

The invention discloses a filter disc, which comprises a filter disc frame and a filter panel, wherein the filter disc frame is detachably connected to an installation frame of a retention basket and is provided with a through hole, the filter panel is connected to the filter disc frame and shields the through hole, and the filter panel is bent and is provided with a plurality of liquid through holes, so that the filter disc has the advantages of large filter area, small flow resistance, high filter efficiency and convenience in installation of the filter disc and the installation frame. The invention also discloses a detention basket formed by assembling the filter discs, so that the detention basket has a large filtering area, is convenient to form a flow passage and has small flow resistance; and the size of installation frame can be changed wantonly as required to the mounted position of entry subassembly is selected according to on-the-spot entry direction, consequently receives on-the-spot space restriction little, and space adaptability is strong.

Description

Detention basket and filter disc thereof

Technical Field

The invention relates to the technical field of nuclear power, in particular to a detention basket suitable for a refueling water tank in a containment and a filter disc thereof.

Background

When a primary circuit of a nuclear power plant reactor is broken, a containment spraying system, a safety injection system and the like are put into use to inject the reactor core and spray the containment. However, when a primary loop pipeline is broken, a large amount of various types of slag can be generated, if the slag is transmitted to the inlets of the safe injection system and the safe spraying system and is deposited on the filter arranged in the safe injection system and the safe spraying system, the pressure drop of a slag layer can be increased, and further, the problems of insufficient flow, cavitation and the like of the safe injection system or the containment spraying system can be caused, so that the safety of the nuclear power station is affected, and therefore the slag must be filtered.

The existing mode is that a filter is arranged at a pump suction inlet of a containment spraying system or a safety injection system and is used for filtering water with a large amount of slag, so that the slag is retained at the upstream of the filter, the water quality entering the downstream of the filter meets the operation requirement of the system, and the phenomenon that excessive slag enters a downstream pipeline and a reactor core to influence the operation of equipment or influence the waste heat of the reactor core to be led out due to the fact that the excessive slag is accumulated in the reactor core is avoided. The existing filter needs a large enough filtering area to ensure the flow required by the system, so the existing filter occupies a large space after being arranged, has poor space adaptability, large flow resistance, low filtering effect and complex and difficult installation process.

Therefore, it is necessary to provide a retention basket with strong space adaptability, convenient installation and high filtering effect to solve the problems existing in the prior art.

Disclosure of Invention

The invention aims to provide a filter disc suitable for a detention basket, so that the detention basket has strong space adaptability, convenient installation and high filtering effect.

The invention also aims to provide the detention basket which has strong space adaptability, convenient installation and high filtering effect.

In order to achieve the purpose, the technical scheme of the invention is as follows: the utility model provides a filter disc, be applicable to and detain the basket, it includes filter disc frame and filtering panel, the filter disc frame is used for detachably to be connected to the installation frame of detaining the basket and is formed with the through-hole on it, filtering panel connect in the filter disc frame shields the through-hole, filtering panel is the form of buckling and has seted up a plurality of logical liquid holes on it.

Preferably, the filter disc frame comprises a plurality of frames connected in sequence, the through holes are formed between the frames in a surrounding manner, and the frames are used for connecting the filter panel and the mounting frame.

Preferably, each of the frames includes a first connecting end and a second connecting end, the first connecting end is used for connecting the filtering panel, and the second connecting end is connected to the mounting frame.

Preferably, the first connecting end and the second connecting end are L-shaped.

Preferably, the filter panel is in a pulse, zigzag or wave structure.

Correspondingly, the invention also discloses a detention basket which comprises a mounting frame, a filter disc, an inlet assembly and a base; the mounting frame is provided with a plurality of mounting side surfaces, and an accommodating space is formed in the mounting frame; the filter disc is sequentially detachably connected to each mounting side surface of the mounting frame; the inlet assembly is connected to any one mounting side surface of the mounting frame and communicated with the accommodating space; the base is connected to either mounting side of the mounting frame and to a mounting surface.

Preferably, the inlet assembly comprises a mouthpiece and a flexible connection structure for connecting the mouthpiece to the mounting frame.

Preferably, the flexible connection structure includes a slider and a fixing structure, the fixing structure is fixed to the mounting frame, and the slider is disposed between the fixing structure and the interface tube in a clearance fit manner.

Preferably, the fixing structure includes a pressing block and a fixing block fixed to the mounting frame, the pressing block is detachably connected to the fixing block and has a gap with the fixing block, and the sliding block is disposed between the fixing block and the pressing block in a clearance fit manner.

Preferably, the clearance between the slide block and one of the fixed block and the pressing block when the slide block is attached to the other one of the fixed block and the pressing block is equal to or less than 1 mm.

Preferably, the slider is annular and is sleeved on the interface tube, and a gap between the inner surface of the slider and the outer surface of the interface tube is equal to or smaller than 1 mm.

Preferably, the fixed block and the compression block are sleeved on the mouthpiece and have the same inner diameters, and the inner diameters of the fixed block and the compression block are larger than the outer diameter of the mouthpiece.

Preferably, the fixing structure further comprises a distance member, the distance member is clamped between the fixing block and the pressing block to form the interval, and the distance member is in clearance fit with the sliding block.

Preferably, the fixing structure further comprises a fixing bolt, the distance member is a hollow cylindrical structure, the number of the fixing bolt and the number of the distance member are multiple, the fixing bolt and the number of the distance member are arranged around the interface tube, and the fixing bolt sequentially penetrates through the pressing block and the distance member and is connected to the fixing block through threads.

Preferably, the base comprises a bottom plate, a connecting plate and a supporting plate, wherein the bottom plate, the connecting plate and the supporting plate are arranged in parallel, the supporting plate is connected between the bottom plate and the connecting plate, the bottom plate is used for being fixed to a mounting surface, and the connecting plate is fixedly connected with the mounting frame; the detention basket is fixed on the mounting surface through the base, the load of the detention basket can be uniformly transmitted to the mounting surface, and the integral bearing performance of the detention basket is improved.

Preferably, the mounting frame is of a cuboid or cube structure.

Compared with the prior art, the filter disc comprises the filter disc frame and the filter panel, the filter disc frame is detachably connected to the installation frame of the retention basket and is provided with the through holes, the filter panel is connected to the filter disc frame and shields the through holes, and the filter panel is bent and is provided with the liquid through holes, so that the filter disc is large in filter area, small in flow resistance, high in filter efficiency, and convenient to install with the installation frame. Correspondingly, the detention basket formed by assembling the filter discs adopts a three-dimensional filter design, a certain number of filter discs are selected for assembly according to needs or installation positions, and each surface of the detention basket is assembled with the filter disc, so that the filter area is large, a flow channel is conveniently formed, and the flow resistance is small; the size of the installation frame can be changed randomly according to needs, the limitation of field space is small, and the space adaptability is strong; and the inlet assembly can be selected to be fixed on any one mounting side surface of the detention basket according to the field inlet direction and position, so that the installation is convenient, and the arrangement flexibility of the detention basket is further improved.

Drawings

FIG. 1 is a schematic view of the structure of a retention basket of the present invention.

Fig. 2 is a schematic view of the structure of a mounting frame of the retention basket of fig. 1.

Fig. 3 is a side view of fig. 2.

Fig. 4 is a top view of the filter tray of the retention basket of fig. 1.

Fig. 5 is a sectional view taken along line a-a of fig. 4.

Fig. 6 is a side view taken along the direction B in fig. 4.

Fig. 7 is an enlarged schematic view of a portion C in fig. 4.

Fig. 8 is an enlarged schematic view of the inlet assembly of fig. 2.

Fig. 9 is an enlarged schematic view of the inlet assembly of fig. 3.

Fig. 10 is a half sectional view of the inlet assembly of fig. 8.

Fig. 11 is an enlarged schematic view of a portion D in fig. 10.

Fig. 12 is an enlarged schematic view of the base of the retention basket of fig. 1.

Detailed Description

Embodiments of the present invention will now be described with reference to the drawings, wherein like element numerals represent like elements. The retention basket 1 provided by the invention is mainly suitable for a refueling water tank in a containment vessel and used for filtering fragments in cooling water, but not limited to the above, and can also be used in other occasions of a nuclear power station.

Referring first to fig. 1-3, the retention basket 1 of the present invention comprises a mounting frame 10, a filter tray 20, an inlet module 30 and a base 40. Wherein, installation frame 10 is three-dimensional structure and has a plurality of installation sides, an accommodation space is formed in installation frame 10, a plurality of filter discs 20 are respectively detachably connected to installation frame 10, so that each installation side of installation frame 10 forms a filter surface, inlet assembly 30 is connected to any installation side of installation frame 10 and is communicated with the accommodation space, and base 40 is connected to an installation side of installation frame 10 and fixes detention basket 1 on the installation side through base 40. The cooling water with the debris under the accident condition enters the detention basket 1 through the inlet assembly 30, and after being filtered by the filter disc 20, the cooling water flows out through the filter disc 20, and the debris is detained in the accommodating space of the detention basket 1.

As shown in fig. 2 to 3, the shape of the mounting frame 10 can be flexibly set according to the needs, and the mounting frame 10 of the present invention is preferably a rectangular parallelepiped structure, and therefore, it has six mounting sides, and each mounting side is mounted with a plurality of filter discs 20, so that the finally formed retention basket 1 has six filter surfaces, a large filter area, a convenient flow channel, and a small flow resistance. Meanwhile, the installation frame 10 can be formed by fixedly connecting a plurality of frame rods 11 on site directly, or frame units with a certain size can be prefabricated in advance, and then the plurality of frame units are assembled to form the installation frame, wherein the frame units can be in a rectangular, square, cuboid, cube and other structures without limitation, so that the size of the installation frame 10 can be changed randomly according to needs, the arrangement of the detention basket 1 is more flexible, the space adaptability is strong, and the limitation of site space is small.

In the present invention, the structure of the mounting frame 10 is not limited to a rectangular parallelepiped, but may be configured to be other structures, for example, a cubic structure, and the manner of assembling the mounting frame 10 is a conventional means in the art, and is not described in detail.

Preferably, a plurality of mounting holes 12 are provided on each mounting side of the mounting frame 10, and each mounting hole 12 is correspondingly provided with a filter tray 20, so that the filter trays 20 are stably connected. Wherein the size of the mounting holes 12 is specifically set according to the size of the selected filter tray 20, and the size of the plurality of mounting holes 12 on each mounting side may be the same or different, thereby further increasing the flexibility of the arrangement of the retention basket 1.

Referring to fig. 4-7, each filter tray 20 comprises a filter tray frame 21 and a filter panel 22, the filter tray frame 21 is detachably connected to the mounting frame 10, a through hole 211 is formed on the filter tray frame 21, the filter panel 22 is connected to the filter tray frame 21 and covers the through hole 211, and a plurality of liquid through holes 221 are formed on the filter panel 22, so that the filter panel 22 can ensure that the cooling water passes through and the fragments are retained in the retention basket 1.

Specifically, the filter tray frame 21 includes a plurality of frames 212 connected in sequence, and the through holes 211 are defined between the frames 212. Each of the frames 212 includes a first connection end 212a and a second connection end 212b (see fig. 5 and 6) bent, the filter panel 22 is welded to the first connection end 212a or fixed to the first connection end 212a by bolts, and the second connection end 212b is fixed to the mounting frame 10 by bolts, so that the assembly of the retention basket 1 is facilitated. Of course, the connection between the filter panel 22 and the filter disc frame 21 and the connection between the filter disc frame 21 and the mounting frame 10 are not limited to the above connection.

As shown in fig. 5-6, the first and second connection ends 212a, 212b are preferably L-shaped, but are not limited to such a shape.

Referring to fig. 4 and 7, in the present invention, the filter panel 22 is formed by bending a punching screen, and a certain bending width L, for example, 5mm to 8mm, is reserved on the punching screen, but the bending width L is not limited thereto, so that the liquid through holes 221 on the bent screen are not deformed, and the filter panel 22 is preferably in a pulse, zigzag or wave structure after being bent, so that the filter panel has a large filter area and good structural strength.

As shown in fig. 2 to 3, the inlet module 30 is selectively installed to either installation side of the installation frame 10 according to the site inlet position, making the retention basket 1 adaptable. Wherein, entry subassembly 30 includes mouthpiece 31 and is used for connecting the flexible connection structure 32 of this mouthpiece 31, and in the mounting hole 12 on the installation side was worn to locate by mouthpiece 31 and made flexible connection structure 32 contradict in frame pole 11, and mouthpiece 31 is used for connecting the on-the-spot entry, and mouthpiece 31 connects through flexible connection structure 32, can enough guarantee that the piece does not flow out from the entrance that is detained basket 1, can guarantee again that the vibrations load on detaining basket 1 does not transmit to the entrance.

As shown in fig. 8-10, the interface tube 31 of the present invention includes a straight tube 311 and a process connection tube 312, wherein one end of the straight tube 311 is fixed to the process connection tube 312 in an abutting manner, and the two are preferably connected by a flange, but not limited thereto, the flexible connection structure 32 is disposed between the frame rod 11 and the straight tube 311, and the process connection tube 312 is used for connecting a field entrance.

Specifically, as shown in fig. 2-3 and 8-11, the flexible connecting structure 32 includes a fixing structure 321 and a slider 322, the fixing structure 321 is fixed between the straight tube 311 and the frame rod 11, and the slider 322 is disposed between the fixing structure 321 and the straight tube 311 in a clearance fit manner.

As shown in fig. 8-11, the fixing structure 321 includes a pressing block 3211, a fixing block 3212, and a distance member 3213. The fixing block 3212 is fixed to the frame bar 11 (shown in fig. 2), and may be fixed by a detachable manner such as bolt fastening or a non-detachable manner such as welding. The compressing block 3211 is detachably connected to the fixing block 3212, and the distance member 3213 is clamped between the fixing block 3212 and the compressing block 3211 to form a space between the fixing block 3212 and the compressing block 3211. The thickness of the distance member 3213 is greater than the thickness of the slider 322, and the slider 322 is disposed between the fixing block 3212 and the pressing block 3211 with a clearance fit by the above-mentioned interval formed by the distance member 3213.

More specifically, the fixed block 3212 is provided with an annular opening, the opening is sleeved outside the straight tube 311, the compressing block 3211 and the slider 322 are also annularly sleeved on the straight tube 311, the straight tube 311 is in clearance fit with the fixed block 3212 and the compressing block 3211, respectively, and the slider 322 is also in clearance fit between the straight tube 311 and the distance member 3213. Preferably, the inner diameters of the fixing block 3212 and the compressing block 3211 are larger than the outer diameter of the straight tube 311, and the vibration of the straight tube 311 drives the slider 322 to generate axial displacement and radial displacement relative to the fixing structure 321.

As shown in fig. 10-11, when the sliding block 322 is tightly attached to one of the fixed block 3212 and the compressing block 3211, the gap between the other is equal to or less than 1mm, the inner diameter of the sliding block 322 is substantially equal to the outer diameter of the straight tube 311, and the gap between the outer surface of the sliding block 322 and the distance member 3213 is equal to or less than 1 mm. The close contact can effectively prevent the entry of fragments larger than 1mm, and can prevent foreign matters such as fine debris from entering the straight tube 311 and the mounting frame 10, thereby achieving a sealing effect. In practical implementation, the gap between the sliding block 322 and the fixing block 3212 or the compressing block 3211 and the gap between the outer surface of the sliding block 322 and the distance member 3213 can be controlled to be less than 0.5mm, so that the sealing effect is further improved. The joint surface between the fixed block 3212 and the slider 322 is a finish machining surface, and the joint surface between the slider 322 and the pressing block 3211 is a finish machining surface, so that the slider 322 can slide up and down relative to the fixed block 3212 and the pressing block 3211. The clearance between the fixed block 3212, the compressing block 3211 and the straight tube 311 is larger than the clearance between the slider 322 and the straight tube 311, so that a clearance with a thin middle and thick two sides can be formed by taking the slider 322 as a center, the flexible connecting structure 32 can effectively overcome the bending generated when the interface tube 31 vibrates, the impact of the bending of the interface tube 31 when the interface tube 31 vibrates on plugging is effectively avoided, and the service life of the plugging is prolonged. Preferably, the inner diameters of the fixing block 3212 and the compressing block 3211 are equal, so that a bilaterally symmetrical gap is formed with the slider 322 as a center, and such a structure can limit the straight tube 311 to vibrate relatively uniformly with the slider 322 as a center as much as possible, and overcome excessive axial displacement of the straight tube 311 during clearance fit.

With reference to fig. 11, the fixing structure 321 further includes a fixing bolt 3214, the distance members 3213 are hollow cylindrical structures, a plurality of fixing bolts 3214 and the distance members 3213 are uniformly arranged around the straight tube 311, and the fixing bolt 3214 sequentially penetrates through the compressing block 3211 and the distance members 3213 and is connected to the fixing block 3212 through a thread.

Referring now to fig. 1, 3 and 12, a plurality of bases 40 are connected to a mounting side surface of the retention basket 1, and the retention basket 1 is fixed to a pre-buried plate 50 of a mounting surface (e.g., the floor surface) via the bases 40. Specifically, the base 40 comprises a bottom plate 41, a connecting plate 42 and a supporting plate 43 connected between the bottom plate and the connecting plate, the bottom plate 41 is fixed to the embedded plate 50 through bolts, the connecting plate 42 is fixedly connected with the mounting frame 10 through bolts, the detention basket 1 is fixed to the embedded plate 50 through the base 40, the load of the detention basket 1 can be uniformly transmitted to the ground, and the overall bearing performance of the detention basket 1 is improved.

As shown in fig. 1, both ends of the mounting frame 10 are also fixedly connected to the base 40 by the side support plates 60, and the side support plates 60 are disposed on the base 40 and fixed to the mounting frame 10 and the base 40 by bolts, respectively, so that the retention basket 1 is more stably and conveniently fixed. In the present invention, the side support plate 60 is preferably an L-shaped angle iron, but is not limited thereto.

The assembly and operation of the retention basket 1 of the present invention will now be described with reference to fig. 1 to 12.

When the detention basket 1 is installed, a proper number of frame rods 11 are selected to be assembled to form an installation frame 10 according to the field installation space, and the frame rods 11 are fixed through bolts; the frame members may be assembled by using frame units prefabricated in advance, and the frame bars 11 of the frame units may be fixed by bolts. In one embodiment of the present invention, the mounting frame 10 is assembled into a rectangular parallelepiped structure.

Then, fix filter plate 20 respectively on each installation side of installation frame 10, namely, with filter plate frame 21 on installation frame 10 through the bolt fastening, obtain after the installation and detain basket 1, consequently detain basket 1 and have six filtration faces, the filter area is big, conveniently forms the runner, and the flow resistance is little.

Next, the inlet module 30 is fixed to a mounting side of the mounting frame 10 according to the field inlet direction, wherein the process connection 312 of the inlet module 30 is used for connecting the field inlet. Specifically, before the interface tube 31 is inserted into the mounting frame 10, the flexible connection structure 32 is installed, that is, the fixing block 3212 is fixed to one of the mounting holes 12 of the mounting frame 10, the fixing block 3212 abuts against the frame rod 11, the slider 322 is attached to the surface of the fixing block 3212, the pressing block 3211 and the distance member 3213 are connected to the fixing block 3212 by the fixing bolt 3214, and the clearance fit conditions of the slider 322 and the fixing block 3212, the pressing block 3211, and the distance member 3213 are respectively checked. Then, the straight tube 311 is inserted into the mounting hole 12 through the flexible connecting structure 32 and is in clearance fit with the fixed block 3212, the slider 322 and the pressing block 3211. When the interface tube 31 is static, the sliding block 322 is statically attached to the outer wall of the straight tube 311, and the fixing block 3212 and the compressing block 3211 are in clearance fit with the outer wall of the straight tube 311. When the interface tube 31 vibrates, the straight tube 311 will generate axial and radial displacement and bending movement, and the slider 322 slides on the outer wall of the straight tube 311 along with the axial displacement of the straight tube 311 due to the clearance fit between the slider 322 and the interface tube 31, and the slider 322 moves between the fixed block 3212 and the pressing block 3211 along with the radial displacement and bending of the straight tube 311. Because the fixed structure 321 is fixed to the mounting frame 10, the slider 322 is in clearance fit between the fixed block 3212, the compressing block 3211 and the distance piece 3213, the fixed block 3212 and the compressing block 3211 can limit the axial displacement of the slider 322, the distance piece 3213 can limit the radial displacement of the slider 322, the limit of the movement displacement of the slider 322 indirectly limits the vibration amplitude of the mouthpiece 31, and the like, and the fixed block 3212 and the compressing block 3211 on both sides of the slider 322 can limit the range of movement of the mouthpiece 31 to offset the vibration of the mouthpiece 31 to a certain extent, the vibration cannot be transmitted into the retention basket 1 through the fixed structure 321, and the mouthpiece 31 and the retention basket 1 are in clearance fit, and the vibration transmission can also be isolated at the connection between the two.

Finally, the base 40 is fixed on the pre-buried plate 50 of the ground by using bolts, and the mounting frame 10 is fixed on the base 40, so that the load of the detention basket 1 can be uniformly transmitted to the ground, and the integral bearing performance of the detention basket is improved; and by the support of base 40, have certain clearance between staying basket 1 and the ground, therefore further increase the filter area who stays basket 1, improve filtration efficiency.

In the assembly process of detaining basket 1, owing to use less connecting piece to the installation of detaining basket 1 is simple, only needs less step can accomplish at the installation scene.

Under the accident condition, the cooling water that has the piece passes through inlet assembly 30 and gets into in staying basket 1, and after the filtering action of filter disc 20, the cooling water goes out to be detained outside basket 1, and the piece then is detained in staying basket 1, because this stay basket 1 has great filter area, and filtration efficiency is high, and the choked flow is little, consequently can guarantee the flow requirement of low reaches system.

In summary, since the filter disc 20 of the present invention includes the filter disc frame 21 and the filter panel 22, the filter disc frame 21 is detachably connected to the mounting frame 10 of the retention basket 1 and has the through hole 211 formed thereon, the filter panel 22 is connected to the filter disc frame 21 and shields the through hole 211, the filter panel 22 is bent and has the plurality of liquid through holes 221 formed thereon, the filter disc 20 and the mounting frame 10 are conveniently mounted, and the filter disc 20 has a large filtering area, a small flow resistance, and a high filtering efficiency. The detention basket 1 formed by assembling the filter discs 20 adopts a three-dimensional filter design, a certain number of filter discs 20 are selected to be assembled according to needs or installation positions, and each surface of the detention basket 1 is assembled with the filter discs 20, so that the filter area is large, a flow passage is conveniently formed, and the flow resistance is small; the size of the installation frame 10 can be changed randomly according to needs, the limitation of field space is small, and the space adaptability is strong; and the inlet assembly 30 can be selected and fixed on any one mounting side surface of the detention basket 1 according to the field inlet direction and position, so that the installation is convenient, and the arrangement flexibility of the detention basket 1 is further improved.

The above disclosure is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the scope of the present invention, therefore, the present invention is not limited by the appended claims.

Claims

1. A retention basket, comprising:

the mounting frame is provided with a plurality of mounting side surfaces, and a containing space is formed in the mounting frame;

the filter discs are sequentially detachably connected to each mounting side surface of the mounting frame;

an inlet assembly connected to any one of the mounting sides of the mounting frame and communicating with the accommodating space;

the base is connected to any one mounting side surface of the mounting frame and connected to a mounting surface;

the filter disc comprises a filter disc frame and a filter panel, the filter disc frame is detachably connected to the mounting side face and is provided with a through hole, the filter panel is connected to the filter disc frame and shields the through hole, and the filter panel is bent and is provided with a plurality of liquid through holes;

the inlet assembly comprises a mouthpiece and a flexible connection structure used for connecting the mouthpiece to the mounting frame, the flexible connection structure comprises a sliding block and a fixed structure, the fixed structure comprises a compression block, a distance piece and a fixed block fixed on the mounting frame, the compression block is detachably connected to the fixed block and has a gap with the fixed block, the distance piece is clamped between the fixed block and the compression block to form the gap, the sliding block is arranged between the fixed block and the compression block in a clearance fit mode, the sliding block is arranged between the distance piece and the fixed block in a clearance fit mode, and the gap between the fixed block, the compression block and the mouthpiece is larger than the gap between the sliding block and the mouthpiece.

2. A retention basket according to claim 1, wherein the filter tray frame comprises a plurality of sequentially connected rims enclosing the through-holes therebetween, the rims for connecting the filter panels and the mounting frame.

3. A retention basket according to claim 2, wherein each of the side frames includes a first connecting end and a second connecting end that are bent.

4. The retention basket according to claim 3, wherein the first and second connection ends are L-shaped.

5. A retention basket according to claim 1, wherein the filtration panels are of a pulse, zig-zag or wave configuration.

6. The retention basket according to claim 1, wherein a gap between the slide block and one of the fixed block and the pressing block when the slide block is attached to the other is equal to or less than 1 mm.

7. The retention basket according to claim 1, wherein the slider is annular and fits over the mouthpiece, and a gap between an inner surface of the slider and an outer surface of the mouthpiece is equal to or less than 1 mm.

8. The retention basket according to claim 1, wherein the fixed block and the compression block are both sleeved on the mouthpiece and have the same inner diameter, and the inner diameters of the fixed block and the compression block are both larger than the outer diameter of the mouthpiece.

9. The retention basket according to claim 1, wherein the fixing structure further comprises a fixing bolt, the distance members are hollow cylindrical structures, a plurality of fixing bolts and a plurality of distance members are arranged around the mouthpiece, and the fixing bolt sequentially penetrates through the pressing block and the distance members and is connected to the fixing block through threads.

10. The retention basket of claim 1, wherein the base includes a base plate disposed in parallel for securing to a mounting surface, a connecting plate fixedly connected to the mounting frame, and a support plate connected therebetween.

11. A retention basket according to claim 1, wherein the mounting frame is of rectangular or cubic configuration.