Screening device

Abstract

The utility model discloses a screening device which comprises a support structure used for bearing, the support structure is provided with an upper-layer screening structure used for preliminarily screening backfill materials and a lower-layer screen structure used for screening the backfill materials in a graded mode, and the upper-layer screening structure is located above the lower-layer screen structure. The upper-layer screening structure and the lower-layer screen structure are obliquely arranged, and the lower-layer screen structure is sequentially provided with a fine material area, a middle material area and a coarse material area from top to bottom. According to the screening device, original soil is directly backfilled after being screened, the production efficiency is improved, funds are saved, the progress is guaranteed, and the construction period is shortened.

Description

Technical Field

[0001] The utility model belongs to the field of pipeline construction, and particularly relates to a screening device, which is especially suitable for the fine soil backfilling construction of the mountainous steep terrain and landform of long-distance pipelines. Background Art

[0002] When natural gas pipelines are laid in mountainous steep sections, most of the soil is rock or a mixture of rock and soil, and the excavated soil in the pipe trench cannot be directly backfilled. The conventional solution is to purchase fine soil for backfilling. However, this solution has the following problems:

[0003] Problem 1: The maximum climbing ability of heavy-duty trucks is 16 to 30°. When the slope exceeds 30°, fine soil transportation cannot be achieved.

[0004] Problem 2: For pipe trench backfilling, a large amount of soil is required. Purchasing soil for backfilling has a high cost, and the layered backfilling has a long construction period.

[0005] Problem 3: The excess rock and soil after replacement is exposed, becoming the source of dust, and the cost of ecological harmless treatment is high. Content of the Utility Model

[0006] Aiming at the problems existing in the prior art, the purpose of the utility model is to provide a screening device. By using this device, the original soil can be screened and directly backfilled, thereby improving production efficiency, saving funds, ensuring progress, and shortening the construction period.

[0007] The technical solution adopted by the utility model is as follows:

[0008] A screening device includes a support structure for bearing weight. An upper screening structure for preliminarily screening backfill materials and a lower screen structure for grading and screening backfill materials are provided on the support structure. The upper screening structure is located above the lower screen structure. The upper screening structure and the lower screen structure are respectively inclined. The lower screen structure is sequentially provided with a fine material area, a medium material area, and a coarse material area from top to bottom.

[0009] Further, the support structure includes two high portal frames and low portal frames arranged at intervals. The height of the high portal frame is greater than the height of the low portal frame. Preferably, the width of the high portal frame is equal to the width of the low portal frame. The high portal frame and the low portal frame respectively include two parallel legs and a connecting rod connecting the two legs. The distance between the high portal frame and the low portal frame is greater than the width of the pipe trench to ensure that the legs are located on both sides of the pipe trench. The width of the high portal frame or the low portal frame can be, for example, 2 - 4m, preferably about 3m. The height of the high portal frame can be, for example, 2 - 4m, preferably about 3m. The height of the low portal frame can be, for example, 1 - 3m, preferably about 2m. The material of the legs and the connecting rod can be, for example, narrow flange H-shaped steel with a specification of HN200*100mm.

[0010] Further, the high gantry and the low gantry are connected by an upper cross beam. The upper cross beam is connected to the tops of the legs of the high gantry and the low gantry. There are two upper cross beams which are arranged in parallel. Since the height of the high gantry is greater than that of the low gantry, the upper cross beam is in a slope shape. The material of the upper cross beam can be, for example, a narrow flange H-beam with the specification of HN200*100mm.

[0011] Further, the upper screening structure includes a plurality of upper screening rods arranged at intervals between the two upper cross beams. The upper screening rods are parallel to the upper cross beams. The distance between adjacent upper screening rods can be, for example, 1 / 20 - 1 / 10 of the length of the connecting rod, preferably about 1 / 15 - 1 / 12 of the length of the connecting rod. The material of the upper screening rods can be, for example, a wide flange H-beam with the specification of HN100*100mm. The distance between adjacent upper screening rods is about 250mm, which is used to filter the filler with a diameter or equivalent diameter less than 250mm.

[0012] Further, a first lower cross beam is provided below one of the upper cross beams, and a second lower cross beam is provided below the other upper cross beam. The first lower cross beam and the second lower cross beam are respectively arranged horizontally. One end of the first lower cross beam is connected to the top of the leg of the low gantry, and the other end extends horizontally to the leg of the high gantry and is fixedly connected. The second lower cross beam is located below the first lower cross beam. The distance between the second lower cross beam and the bottom end of the leg can be, for example, 1 / 8 - 1 / 30 of the height of the leg of the low gantry, preferably about 1 / 10 - 1 / 20. The material of the first lower cross beam and the second lower cross beam can be, for example, a wide flange H-beam with the specification of HN100*100mm.

[0013] Further, a diagonal beam is connected between the legs of the high gantry and the low gantry respectively. The top end of the diagonal beam is preferably aligned with the first lower cross beam, and the bottom end of the diagonal beam is preferably aligned with the second lower cross beam. The material of the diagonal beam can be, for example, a wide flange H-beam with the specification of HN100*100mm.

[0014] Further, the lower screen structure includes two partition skeletons arranged at intervals between the two diagonal beams. The partition skeletons are parallel to the first lower cross beam and the second lower cross beam. The two partition skeletons are preferably connected to the trisection points of the diagonal beams. The two partition skeletons are the upper partition skeleton and the lower partition skeleton from top to bottom. The fine material area, the medium material area and the coarse material area are divided by the partition skeletons as the demarcation lines. The material of the partition skeletons can be, for example, a wide flange H-beam with the specification of HN100*100mm.

[0015] Further, the fine material area includes a plurality of reinforcing ribs arranged between the upper partition skeleton and the first lower cross beam. The reinforcing ribs are parallel to the diagonal beams. The distance between adjacent reinforcing ribs can be, for example, 1 / 5 - 1 / 7 between the first lower cross beams, preferably about 1 / 6. The reinforcing ribs can be, for example, round steel with a diameter of φ20.

[0016] Further, a steel wire screen is laid on the upper surface of the reinforcing rib. The aperture of the steel wire screen can be, for example, 10 - 35 mm, preferably about 20 mm. The steel wire screen is, for example, welded and connected to the upper partition framework, the first lower cross beam, and the inclined beam.

[0017] Further, the middle material area includes multiple middle material sieve rods connected between the upper partition framework and the lower partition framework. The middle material sieve rods are parallel to the inclined beam. The distance between adjacent middle material sieve rods can be, for example, 80 - 150 mm, preferably about 100 mm. The middle material sieve rods can be, for example, round steel with a diameter of φ20.

[0018] Further, the coarse material area includes multiple coarse material sieve rods connected between the lower partition framework and the second lower cross beam. The coarse material sieve rods are parallel to the inclined beam. The distance between adjacent coarse material sieve rods is greater than the distance between adjacent middle material sieve rods. The distance between adjacent coarse material sieve rods can be, for example, 150 - 250 mm, preferably about 200 mm. The coarse material sieve rods can be, for example, round steel with a diameter of φ20.

[0019] Further, a stabilizing bottom beam is connected between the legs of the high portal frame and the low portal frame respectively. The stabilizing bottom beam is, for example, perpendicularly connected to the legs.

[0020] Further, lifting rings are respectively fixed on the connecting rods of the high portal frame and the low portal frame. The lifting rings are preferably fixed at the midpoints of the connecting rods, and the lifting rings are preferably detachable lifting rings.

[0021] Advantages of the present utility model:

[0022] The screening device provided by the present utility model adopts a double - layer screen design of an upper - layer screening structure and a lower - layer screen structure. The upper - layer screening structure is laterally inclined to directly discard unqualified backfill materials outside the trench. The lower - layer screen structure is segmented, and the gap transitions from dense to sparse, dividing the backfill materials into three grades of fine, medium, and coarse, which are sequentially dropped at different places in the trench. The screening device provided by the present utility model centrally realizes the screening and elimination of unqualified materials of the backfill materials and the multi - part use of qualified materials after grading, solving the problems of no qualified materials for backfilling in the trench in mountainous areas and the layered use of backfill materials. Description of the Drawings

[0023] Figure 1 is the overall structural schematic diagram of the screening device of the present utility model.

[0024] Figure 2 is the schematic diagram of the upper - layer screening structure.

[0025] Figure 3 is the schematic diagram of the lower - layer screen structure.

[0026] Reference Signs:

[0027] 11 - Low gantry, 12 - High gantry, 13 - Upper crossbeam, 14 - Stable bottom beam, 15 - First lower crossbeam, 16 - Diagonal beam, 17 - Second lower crossbeam, 21 - Leg, 22 - Upper screening structure, 221 - Upper screening rod, 23 - Partition framework, 231 - Upper partition framework, 232 - Lower partition framework, 24 - Fine material area, 25 - Medium material area, 251 - Medium material screening rod, 26 - Coarse material area, 261 - Coarse material screening rod, 27 - Reinforcing rib, 28 - Wire mesh, 29 - Suspension ring, 30 - Connecting rod. Detailed implementation mode

[0028] The present utility model will be further described below in conjunction with the attached drawings.

[0029] As Figures 1-3 shown, a screening device includes a support structure for bearing weight. An upper screening structure 22 for preliminarily screening backfill and a lower screen structure for grading and screening backfill are provided on the support structure. The upper screening structure 22 is located above the lower screen structure. The upper screening structure 22 and the lower screen structure are respectively inclined. The lower screen structure is sequentially provided with a fine material area 24, a medium material area 25, and a coarse material area 26 from top to bottom.

[0030] The support structure includes two high gantries 12 and low gantries 11 arranged at intervals. Preferably, the width of the high gantry 12 is equal to the width of the low gantry 11. The height of the high gantry 12 is greater than the height of the low gantry 11. The high gantry 12 and the low gantry 11 respectively include two parallel legs 21 and a connecting rod 30 connecting the two legs 21. The distance between the high gantry 12 and the low gantry 11 is greater than the width of the trench to ensure that the legs 21 are located on both sides of the trench. The width of the high gantry 12 or the low gantry 11 can be, for example, 2 - 4m, preferably about 3m. The height of the high gantry 12 can be, for example, 2 - 4m, preferably about 3m. The height of the low gantry 11 can be, for example, 1 - 3m, preferably about 2m. The material of the legs 21 and the connecting rod 30 can be, for example, a narrow flange H - shaped steel of HN200*100mm specification.

[0031] The high gantry 12 and the low gantry 11 are connected by an upper crossbeam 13. The upper crossbeam 13 is connected to the tops of the legs 21 of the high gantry 12 and the low gantry 11. There are two upper crossbeams 13 and they are arranged in parallel. Since the height of the high gantry 12 is greater than the height of the low gantry 11, the upper crossbeam 13 is in a slope shape. The material of the upper crossbeam 13 can be, for example, a narrow flange H - shaped steel of HN200*100mm specification.

[0032] The upper screening structure 22 includes a plurality of upper screening rods 221 arranged at intervals between two upper cross beams 13. The upper screening rods 221 are parallel to the upper cross beams 13. The distance between adjacent upper screening rods 221 can be, for example, 1 / 20 - 1 / 10 of the length of the connecting rod 30, preferably about 1 / 15 - 1 / 12 of the length of the connecting rod 30. The material of the upper screening rods 221 can be, for example, a wide flange H-beam with a specification of HN100*100mm. The distance between adjacent upper screening rods 221 is about 250mm, which is used to filter fillers with a diameter or equivalent diameter less than 250mm.

[0033] A first lower cross beam 15 is provided below one of the upper cross beams, and a second lower cross beam 17 is provided below the other upper cross beam. The first lower cross beam 15 and the second lower cross beam 17 are horizontally arranged respectively. One end of the first lower cross beam 15 is connected to the top end of the leg 21 of the low gantry 11, and the other end extends horizontally to the leg 21 of the high gantry 12 and is fixedly connected. The second lower cross beam 17 is located below the first lower cross beam 15. The distance between the second lower cross beam 17 and the bottom end of the leg 21 can be, for example, 1 / 8 - 1 / 30 of the height of the leg 21 of the low gantry 11, preferably about 1 / 10 - 1 / 20. The material of the first lower cross beam 15 and the second lower cross beam 17 can be, for example, a wide flange H-beam with a specification of HN100*100mm.

[0034] An inclined beam 16 is connected between the legs 21 of the high gantry 12 and the low gantry 11 respectively. The top end of the inclined beam 16 is preferably aligned with the first lower cross beam 15, and the low end of the inclined beam 16 is preferably aligned with the second lower cross beam 17. The material of the inclined beam 16 can be, for example, a wide flange H-beam with a specification of HN100*100mm.

[0035] The lower screen structure includes two partition skeletons 23 arranged at intervals between two inclined beams 16. The partition skeletons 23 are parallel to the first lower cross beam 15 and the second lower cross beam 17. The two partition skeletons 23 are preferably connected to the trisection points of the inclined beam 16. The two partition skeletons are the upper partition skeleton 231 and the lower partition skeleton 232 from top to bottom in sequence. The fine material area 24, the medium material area 25 and the coarse material area 26 are divided with the partition skeleton 23 as the boundary line. The material of the partition skeleton 23 can be, for example, a wide flange H-beam with a specification of HN100*100mm.

[0036] The fine material area 24 includes a plurality of reinforcing ribs 27 arranged between the upper partition skeleton 231 and the first lower cross beam 15. The reinforcing ribs 27 are parallel to the inclined beam 16. The distance between adjacent reinforcing ribs 27 can be, for example, 1 / 5 - 1 / 7 of the first lower cross beam 15, preferably about 1 / 6. The reinforcing ribs 27 can be, for example, round steel with a diameter of φ20.

[0037] The upper surface of the reinforcing rib 27 is covered with a steel wire screen 28. The aperture of the steel wire screen 28 can be, for example, 10 - 35 mm, preferably about 20 mm. The steel wire screen 28 is, for example, welded to the upper partition frame 231, the first lower cross beam 15, and the inclined beam 16.

[0038] The middle material area 25 includes multiple middle material screening rods 251 connected between the upper partition frame 231 and the lower partition frame 232. The middle material screening rods 251 are parallel to the inclined beam 16. The distance between adjacent middle material screening rods 251 can be, for example, 80 - 150 mm, further 90 - 110 mm, preferably about 100 mm. The middle material screening rods 251 can be, for example, round steel with a diameter of φ20.

[0039] The coarse material area 26 includes multiple coarse material screening rods 261 connected between the lower partition frame 232 and the second lower cross beam 17. The coarse material screening rods 261 are parallel to the inclined beam 16. The distance between adjacent coarse material screening rods 261 is greater than the distance between adjacent middle material screening rods 251. The distance between adjacent coarse material screening rods 261 can be, for example, 150 - 250 mm, further 160 - 210 mm, preferably about 200 mm. The coarse material screening rods 261 can be, for example, round steel with a diameter of φ20.

[0040] A stabilizing bottom beam 14 is connected between the legs 21 of the high gantry 12 and the low gantry 11 respectively. The stabilizing bottom beam 14 is, for example, perpendicularly connected to the legs 21.

[0041] Lifting rings 29 are respectively fixed on the connecting rods 30 of the high gantry 12 and the low gantry 11. The lifting rings 29 are preferably fixed at the midpoints of the connecting rods 30, and the lifting rings 29 are preferably detachable lifting rings. Embodiment

[0042] A screening device, which includes a support structure for bearing weight. An upper screening structure 22 for preliminarily screening backfill material and a lower screen structure for grading and screening backfill material are provided on the support structure. The upper screening structure 22 is located above the lower screen structure. The upper screening structure 22 and the lower screen structure are respectively inclined. The lower screen structure is sequentially provided with a fine material area 24, a middle material area 25, and a coarse material area 26 from top to bottom.

[0043] The support structure includes two high gantries 12 and two low gantries 11 arranged at intervals. The widths of both the high gantry 12 and the low gantry 11 are 3 m. The height of the high gantry 12 is 3 m, and the height of the low gantry 11 is 2 m. The high gantry 12 and the low gantry 11 respectively include two parallel legs 21 and a connecting rod 30 connecting the two legs 21. The distance between the high gantry 12 and the low gantry 11 is 3 m, which is greater than the width of the trench to ensure that the legs 21 are located on both sides of the trench. The materials of the legs 21 and the connecting rod 30 are narrow flange H - shaped steel of HN200 * 100 mm specification.

[0044] The high portal frame 12 and the low portal frame 11 are connected by an upper cross beam 13. The upper cross beam 13 is connected to the tops of the legs 21 of the high portal frame 12 and the low portal frame 11. There are two upper cross beams 13 which are arranged in parallel. Since the height of the high portal frame 12 is greater than that of the low portal frame 11, the upper cross beam 13 is in a slope shape. The upper cross beam 13 is a narrow flange H-shaped steel of HN200*100mm specification.

[0045] The upper screening structure 22 includes a plurality of upper screening rods 221 arranged at intervals between the two upper cross beams 13. The upper screening rods 221 are parallel to the upper cross beams 13. The material of the upper screening rods 221 is wide flange H-shaped steel of HN100*100mm specification. The distance between adjacent upper screening rods 221 is about 250mm, which is used to filter the filler with a diameter or equivalent diameter less than 250mm.

[0046] A first lower cross beam 15 is provided below one of the upper cross beams 13, and a second lower cross beam 17 is provided below the other upper cross beam 13. The first lower cross beam 15 and the second lower cross beam 17 are respectively arranged horizontally. One end of the first lower cross beam 15 is connected to the top of the leg 21 of the low portal frame 11, and the other end extends horizontally to the leg 21 of the high portal frame 12 and is fixedly connected. The second lower cross beam 17 is located below the first lower cross beam 15. The distance between the second lower cross beam 17 and the bottom end of the leg 21 is 10cm. The materials of the first lower cross beam 15 and the second lower cross beam 17 are wide flange H-shaped steels of HN100*100mm specification.

[0047] A diagonal beam 16 is connected between the legs 21 of the high portal frame 12 and the low portal frame 11 respectively. The top end of the diagonal beam 16 is preferably aligned with the first lower cross beam 15, and the bottom end of the diagonal beam 16 is preferably aligned with the second lower cross beam 17. The material of the diagonal beam 16 is wide flange H-shaped steel of HN100*100mm specification.

[0048] The lower screen structure includes two partition skeletons arranged at intervals between the two diagonal beams 16. The partition skeletons are parallel to the first lower cross beam 15 and the second lower cross beam 17. The two partition skeletons are connected to the trisection points of the diagonal beams 16. The two partition skeletons are the upper partition skeleton 231 and the lower partition skeleton 232 from top to bottom. The fine material area 24, the medium material area 25 and the coarse material area 26 are divided with the partition skeleton as the demarcation line. The material of the partition skeleton can be wide flange H-shaped steel of HN100*100mm specification.

[0049] The fine material area 24 includes a plurality of reinforcing ribs 27 arranged between the upper partition skeleton 231 and the first lower cross beam 15. The reinforcing ribs 27 are parallel to the diagonal beam 16. The distance between adjacent reinforcing ribs 27 is 0.5m. The reinforcing ribs 27 are round steel with a diameter of φ20.

[0050] The upper surface of the reinforcing rib 27 is covered with a steel wire screen 28. The aperture of the steel wire screen 28 is about 20 mm. The steel wire screen 28 is welded to the upper partition framework 231, the first lower cross beam 15 and the inclined beam 16.

[0051] The middle material area 25 includes multiple middle material screening rods 251 connected between the upper partition framework 231 and the lower partition framework 232. The middle material screening rods 251 are parallel to the inclined beam 16. The distance between adjacent middle material screening rods 251 is about 100 mm. The middle material screening rods 251 are round steel with a diameter of φ20.

[0052] The coarse material area 26 includes multiple coarse material screening rods 261 connected between the lower partition framework 232 and the second lower cross beam 17. The coarse material screening rods 261 are parallel to the inclined beam 16. The distance between adjacent coarse material screening rods 261 is greater than the distance between adjacent middle material screening rods 251. The distance between adjacent coarse material screening rods 261 is about 200 mm. The coarse material screening rods 261 are round steel with a diameter of φ20.

[0053] A stable bottom beam 14 is connected between the legs 21 of the high gantry 12 and the low gantry 11 respectively. The stable bottom beam 14 is perpendicularly connected to the legs 21.

[0054] Lifting rings 29 are respectively fixed on the connecting rods 30 of the high gantry 12 and the low gantry 11. The lifting rings 29 are preferably fixed at the midpoints of the connecting rods 30. The lifting rings 29 are preferably snap rings. The lifting rings 29 are connected to the wire rope sleeve of the excavator and serve as the lifting points for the hoisting and movement of the screening device. The length of the wire rope sleeve is appropriately shortened on the side of the high gantry 12 considering the center of gravity and appropriately lengthened on the side of the low gantry 11.

[0055] The operation method of the screening device of the present utility model:

[0056] (1) When backfilling the trench, use the back hook of the excavator to hoist the screening device into place. The high gantry 12 and the low gantry 11 are located on both sides of the trench, with the fine material area 24 in the front, above the exposed pipeline, and the port of the pipeline is arranged below the upper partition framework 231, and other partitions are in the back, outside the trench.

[0057] (2) The excavator stands on one side of the trench where the original soil is stacked and grabs the original soil for feeding. The backfill material with a diameter greater than 250 mm rolls from high to low through the upper screening structure 22 and laterally falls outside the trench. The remaining backfill material falls on the lower screening structure. First, the fine material with a particle size less than 20 mm falls on the pipeline. Then, the middle material with a particle size less than 100 mm falls outside the pipeline port. Finally, the coarse material with a particle size less than 200 mm falls outside the trench. Repeat the feeding and screening until the fine material falling in the fine material area 24 of the backfill material fills the pipeline to the required thickness.

[0058] (3)The forward moving device positions the middle material area 25 above the fine material that has been backfilled, and then screening and backfilling are carried out. By repeating the operation in this order, the backfilling of the bottom fine material, the middle material in the middle layer, and the coarse material in the upper layer can be achieved.

[0059] The preferred embodiments of the present invention have been described above. However, the above description is not for the purpose of limitation. Those of ordinary skill in the art can make many changes or modifications to the present invention without departing from the gist and scope of the present invention. Such changes or modifications should be incorporated within the scope of the appended claims.

Claims

1. A screening device, characterized in that: The invention comprises a support structure for bearing a load, an upper screening structure (22) for preliminary screening of backfill materials and a lower screen structure for graded screening of backfill materials are arranged on the support structure, the upper screening structure (22) is located above the lower screen structure, the upper screening structure (22) and the lower screen structure are arranged at an angle, respectively, and the lower screen structure is provided with a fine material area (24), a medium material area (25) and a coarse material area (26) in sequence from top to bottom.

2. The screening device according to claim 1, characterized in that: The support structure comprises two high door frames (12) and a low door frame (11) which are arranged at intervals. The height of the high door frame (12) is greater than the height of the low door frame (11). The high door frame (12) and the low door frame (11) respectively comprise two parallel legs (21) and a connecting rod (30) connecting the two legs (21). The distance between the high door frame (12) and the low door frame (11) is greater than the width of the pipe trench, so as to ensure that the legs (21) are located on both sides of the pipe trench.

3. The screening device according to claim 2, characterized in that: The high door frame (12) and the low door frame (11) are connected via an upper crossbeam (13), and the upper crossbeam (13) is connected to the top ends of the legs (21) of the high door frame (12) and the low door frame (11). There are two upper crossbeams (13) which are arranged in parallel and are sloped.

4. The screening device according to claim 3, characterized in that: The upper screening structure (22) comprises a plurality of upper screening bars (221) arranged at intervals between two upper cross beams (13), and the upper screening bars (221) are parallel to the upper cross beams (13).

5. The screening device according to claim 4, characterized in that: A first lower crossbeam (15) is provided below one of the upper crossbeams, and a second lower crossbeam (17) is provided below the other upper crossbeam. The first lower crossbeam (15) and the second lower crossbeam (17) are respectively arranged horizontally. One end of the first lower crossbeam (15) is connected to the top of the leg (21) of the low portal frame (11), and the other end extends horizontally to the leg (21) of the high portal frame (12) and is fixedly connected thereto. The second lower crossbeam (17) is located below the first lower crossbeam (15).

6. The screening device according to any one of claims 2 to 5, characterized in that: An inclined beam (16) is connected between the supporting legs (21) of the high portal frame (12) and the low portal frame (11), the top end of the inclined beam (16) is aligned with the first lower cross beam (15), and the bottom end of the inclined beam (16) is aligned with the second lower cross beam (17).

7. The screening device according to claim 6, characterized in that: The lower screen structure comprises two partition frames (23) arranged at intervals between two inclined beams (16); the partition frames (23) are parallel to the first lower cross beam (15) and the second lower cross beam (17); the two partition frames are, from top to bottom, an upper partition frame (231) and a lower partition frame (232); the fine material area (24), the medium material area (25) and the coarse material area (26) are divided by the partition frames (23) as a dividing line.

8. The screening device according to claim 7, characterized in that: The fine material area (24) includes a plurality of reinforcing ribs (27) arranged between the upper partition frame (231) and the first lower layer cross beam (15), and the reinforcing ribs (27) are parallel to the inclined beam (16).

9. The screening device according to claim 8, characterized in that: The upper surface of the reinforcing rib (27) is paved with a steel wire mesh (28).

10. The screening device according to claim 9, characterized in that: The middle material area (25) includes a plurality of middle material screening bars (251) connected between the upper partition frame (231) and the lower partition frame (232), and the middle material screening bars (251) are parallel to the inclined beam (16). The coarse material zone (26) comprises a plurality of coarse material screening bars (261) connected between the lower partition frame (232) and the second lower layer cross beam (17), the coarse material screening bars (261) being parallel to the inclined beam (16), and the distance between adjacent coarse material screening bars (261) being greater than the distance between adjacent medium material screening bars (251).

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