Cone type rolling screen with multi-layer screen structure

Abstract

The invention belongs to the technical field of quartz sand screening processes and equipment, and particularly relates to a conical roller screen with a multi-layer screen structure. The front end of a production line is not provided with an efficient and special impurity screening device, and a simple grating or manual sorting is mostly adopted, so that the problems of incomplete screening, high labor intensity, easiness in blockage and the like exist. Therefore, the special screening equipment capable of efficiently and continuously removing the impurities in the raw ore is urgently needed and is arranged behind a sand dredger and in front of a hydraulic classifier so as to guarantee stable operation and product quality of a whole production line. The invention provides a conical roller screen with a multi-layer screen structure, which is arranged at the front end of a silica sand mining and dressing production line, is positioned between a raw ore outlet provided by a sand dredger and a hydraulic classifier, and is mainly used for screening out non-silica sand raw materials such as branches, garbage and sundries in raw ores. The device has the characteristics of high screening efficiency, high treatment capacity, difficulty in blockage, compact structure and the like.

Description

Technical Field

[0001] This invention belongs to the technical field of quartz sand screening process and equipment, specifically relating to a cone-shaped rolling screen with a multi-layer screen structure. Background Technology

[0002] Quartz sand, as an important industrial mineral raw material, is widely used in many industries such as glass, electronics, casting, metallurgy, chemicals, cement, ceramics, and refractory materials. The classification of silica sand mainly employs screening and hydraulic classification methods. Hydraulic classification is carried out in a hindered settling tank, utilizing the differences in settling velocity of sand particles in water to achieve separation by particle size. During operation, the hydraulic classifier forms a floating layer, a suspended layer, and a settling layer within the classification container, located in the upper, middle, and lower layers, respectively. To achieve the required classification accuracy and productivity, a high degree of dispersion among sand particles of different sizes is necessary, requiring a sufficiently large equipment cross-sectional size. A typical silica sand mining and beneficiation production line includes continuous operations such as raw sand collection, conveying, primary desliming and impurity removal, washing, classification, and concentration.

[0003] In existing technologies, silica sand ore, after being supplied by dredgers, typically proceeds directly to subsequent desliming, washing, and hydraulic classification processes. However, the ore often contains impurities such as branches, plastics, weeds, and household waste. If these impurities directly enter subsequent equipment, they can not only clog pipes and wear down equipment, but also affect the accuracy and efficiency of hydraulic classification, and even lead to a decline in product quality. Currently, the production line lacks efficient and dedicated impurity screening devices at the front end, often relying on simple grids or manual sorting, which suffers from incomplete screening, high labor intensity, and susceptibility to clogging. Therefore, there is an urgent need for a dedicated screening device capable of efficiently and continuously removing impurities from the ore, installed after the dredger and before the hydraulic classifier, to ensure the stable operation of the entire production line and product quality. Summary of the Invention

[0004] The purpose of this invention is to provide a cone-shaped rotary screen with a multi-layer screen structure, which is set at the front end of the silica sand mining and beneficiation production line, located between the raw ore outlet provided by the sand dredger and the hydraulic classifier. It is mainly used to screen out non-silica sand raw materials such as branches, garbage, and debris in the raw ore. It has the characteristics of high screening efficiency, large processing capacity, not easy to clog, and compact structure.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A conical rotary screen with a multi-layer screen structure is characterized by, The rotary screen includes a shell, a feeding device, a conical drum screen body, and a drive device; The shell is used to construct the supporting structure of the rotary screen and serves as a receiving container for the conical drum screen body; The feeding device is located above the feed end of the conical drum screen body and is used to receive the raw ore from the sand dredger and guide it into the screen body; the feeding device includes a feed chute that extends into the interior of the conical drum screen body to ensure that the material can smoothly enter the conical drum screen body. The conical drum screen body includes a feed end, a discharge end, and a screening end. The conical drum screen body is shaped like a truncated cone, meaning the feed end has a smaller diameter and the screening end has a larger diameter. The axis of the conical drum screen body is installed parallel to the horizontal plane or at a certain angle. The conical drum screen body has at least two coaxially arranged screens from the inside to the outside. When there are two screens, they are an inner screen and an outer screen. The inner screen has a larger mesh size, and the outer screen has a smaller mesh size. The discharge end is located below the conical drum screen body and mainly consists of an inverted conical collecting device located at the bottom of the shell. The drive unit is used to drive the conical drum screen body to rotate around its axis; the drive unit includes a motor, a reducer, and a transmission mechanism, which is implemented by any one of gear transmission, sprocket and chain transmission, or roller friction transmission.

[0006] The conical drum screen body is provided with a rotating shaft, which is assembled on the housing through a bearing seat. At least two sets of screen supports are provided on the rotating shaft, and screen wall frames are provided on the circumferential surface between the screen supports. The screen wall frames are used to construct the outer circumferential contour of the conical drum screen body, and the screen is attached to the screen wall frames.

[0007] The feeding device includes a buffer well and a feeding pipe. The buffer well is a vertical tube. The feeding chute is located on the side of the buffer well. The side of the buffer well has an opening that connects the feeding chute and the buffer well. The upper end of the buffer well is above the feeding chute, and the lower end is flush with the bottom of the shell.

[0008] The screening end is located on the side of the conical drum screen body with the larger opening diameter. After screening, large impurities trapped by the inner screen and small and medium-sized impurities trapped by the outer screen are discharged from the screening end under the guiding action of the screen body's rotation and the conical structure. A debris collection hopper or conveyor belt is provided below the screening end to collect and transport the screened impurities away.

[0009] The screen has 2-3 layers, from the inside out: coarse screen, medium screen, and fine screen. The screen aperture diameter of each screen is defined as follows: coarse screen aperture diameter > medium screen aperture diameter > fine screen aperture diameter; there is a gap between adjacent screens.

[0010] The interval between the coarse screen and the medium screen is 2-3 times the diameter of the coarse screen aperture, and the interval between the medium screen and the fine screen is 1.5-2 times the diameter of the medium screen aperture.

[0011] The discharge end of the conical drum screen is located at the bottom of the screen body. Silica sand raw material (fine material) meeting the particle size requirements falls through the outer screen during the screening process. A fine material collection device is used to collect this material and guide it to subsequent processes (such as desliming, washing, etc.). The fine material collection device is typically a hopper located below the screen body, with a discharge port at the bottom, which may be connected to a screw conveyor or chute to transport the material to the next piece of equipment.

[0012] The beneficial effects of this invention are as follows: High-efficiency pre-screening: By setting up multiple layers of conical screens with different apertures, impurities of different sizes in the raw ore can be screened out step by step, resulting in high screening efficiency and effective protection of subsequent hydraulic classification equipment; Continuous automated operation: The equipment can continuously feed and discharge materials, adapting to the needs of continuous operation in silica sand production lines. It has a high degree of automation and reduces the intensity of manual labor. Not prone to clogging: The conical drum structure, combined with the rotational motion and possible internal cleaning device, makes the material continuously roll and move forward in the screen body, effectively preventing screen hole clogging and ensuring the continuity of production; Reasonable structure and large processing capacity: The conical design increases the screening area and improves the processing capacity; the inclined installation utilizes gravity to assist in material conveying, resulting in relatively low energy consumption. Highly adaptable: By adjusting the number of screen layers, mesh size, and screen body inclination angle, it can adapt to silica sand ore from different sources and with different impurity contents. Attached Figure Description

[0013] The attached figures for this application are as follows: Figure 1 This is a schematic diagram of the overall structure of the cone-shaped rotating screen of the present invention; Figure 2 This is a schematic diagram of the structure of the conical rotating screen of the present invention, which has a screen support wall and an exposed screening end; Figure 3 This is a schematic diagram of the conical rotating screen of the present invention, omitting the screen support wall and exposing the screening end; Figure 4 This is a schematic diagram of the structure of the buffer well and the screening end of the exposed feeding device of the conical rolling screen of the present invention.

[0014] In the picture: 10. Feeding device; 11. Feed chute; 12. Buffer well; 13. Feed pipe; 20. Conical drum screen body; 21. Feed end; 22. Discharge end; 23. Screening end; 24. Screen mesh; 25. Rotating shaft; 26. Screen mesh support; 27. Screen mesh support wall; 30. Drive unit; 31. Motor; 32. Transmission mechanism; 40. Shell; 41. Inverted cone-shaped collecting device; 42. Debris collecting hopper. Detailed Implementation

[0015] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0016] Example 1.

[0017] like Figure 1-3 As shown, the cone-shaped rotary screen with a multi-layer screen structure described in this embodiment includes a shell, a feeding device, a cone-shaped drum screen body, and a drive device. The shell is used to construct the support structure of the rotary screen and serves as a receiving container for the cone-shaped drum screen body. The shell is usually rectangular in structure and made of metal. The shell is both the working chamber of the cone-shaped drum screen body and the support platform for assembling the feeding device, drive device, and cone-shaped drum screen body. Its specific structure can be flexibly set according to the rules and connection relationships of the above-mentioned components, and will not be described in detail here. The feeding device is located above or on the side of the feeding end of the cone-shaped drum screen body. It is used to receive the raw ore from the sand dredger and guide it into the screen body. Here, it refers to the raw ore flowing into the screen body by gravity, hence the term "above". The feeding device includes a feeding chute, which extends into the interior of the cone-shaped drum screen body to ensure that the material can smoothly enter the cone-shaped drum screen body.

[0018] The conical drum screen body is the core component of the conical rotary screen. It includes a feed end, a discharge end, and a screening end. The feed end and screening end are located on two end faces of the screen body, respectively. The discharge end is the channel through which materials can pass through the screen holes and flow into the shell, and then be discharged through the inverted conical collecting device at the bottom of the shell. This is the channel through which the conical rotary screen conveys the main materials to subsequent processes. The conical drum screen body is shaped like a truncated cone, meaning the feed end has a smaller diameter and the screening end has a larger diameter. The axis of the conical drum screen body is installed parallel to the horizontal plane or at a certain angle. When the screen body is installed horizontally, the conical structure of the screen body itself can also transfer the impurities retained in the screen body to the screening end during the rolling process of the screen body, although the speed is slower compared to when the screen body is installed at a certain angle to the axis. The conical drum screen body has at least two coaxially arranged screens from the inside to the outside. When there are two screens, they are the inner screen and the outer screen. The inner screen has a larger mesh size, while the outer screen has a smaller mesh size. The discharge end is located below the conical drum screen body and is mainly composed of an inverted conical collecting device at the bottom of the shell. The discharge end is used to discharge debris that has not passed through the conical drum screen body.

[0019] The drive unit is used to drive the conical drum screen body to rotate around its axis; the drive unit includes a motor, a reducer, and a transmission mechanism, which can be implemented using any one of gear transmission, sprocket and chain transmission, or roller friction transmission. The implementation of the drive unit is relatively common and will not be described in detail.

[0020] The conical drum screen body is equipped with a rotating shaft, which is mounted on the housing via bearing seats. At least two sets of screen supports are mounted on the rotating shaft, and screen wall frames are provided on the circumferential surface between the screen supports. These screen wall frames form the outer circumferential contour of the conical drum screen body, and the screen is attached to these screen wall frames. The screen supports function to support the screen wall frames outward from the rotating shaft, and also to bear the large amount of material conveyed by the feeding device, as well as the total weight of the screen body during its rotation. The screen wall frames are surface support structures laid on the circumferential surface of the screen body, and also serve as the foundation for assembling and fixing the screen. Furthermore, when the screen body structure is constructed using an intermediate rotating shaft, screen supports, and screen wall frames, there are no other obstructions on the circumferential surface of the conical screen body, which greatly facilitates subsequent installation, maintenance, and replacement of the screen. In addition, based on the above structure, the feed chute extends from the outside into the screen body to transport the raw material into the screen body without leakage. Therefore, the screen supports near the feed end need to reserve space to accommodate the feed chute.

[0021] Example 2.

[0022] like Figure 4 As shown, based on the above embodiments, the feeding device in this embodiment includes a buffer well and a feeding pipe. The buffer well is a vertical pipe, and the feeding chute is located on the side of the buffer well. The side of the buffer well has an opening that connects the feeding chute and the buffer well. The upper end of the buffer well is above the feeding chute, and the lower end is flush with the bottom of the shell. In actual working conditions, the feeding pipe is connected to a distant sand dredger to supply raw ore slurry to the production line. The raw ore transported by the dredger is unprocessed and may contain many unknown branches, garbage, and other debris. Furthermore, due to unstable factors such as flow rate and pressure during the sand dredging process, there is a high possibility of unpredictable impact on the feeding chute, and there is a possibility of raw ore leakage directly into the discharge end. Therefore, in this embodiment, the end of the feeding pipe is placed inside the buffer well. By expanding the space, the unstable factors of the raw ore are released and balanced, and then the ore flows into the feeding chute through a diffuse flow, thus stabilizing the supply of raw ore.

[0023] The screening end is located on the side of the conical drum screen body with the larger opening diameter. After screening, large impurities trapped by the inner screen and small and medium-sized impurities trapped by the outer screen are discharged from the screening end under the guidance of the screen body's rotation and the conical structure. A debris collection hopper or conveyor belt is located below the screening end to collect and remove the screened impurities. Furthermore, the debris collection hopper below the screening end should have a lateral opening larger than the diameter of the screening end, and side baffles close to the screen body. The lowest point of the upper edge of the debris collection hopper should be higher than the bottom of the casing, ensuring that impurities can completely enter the collection hopper without leakage, and minimizing the amount of screened mortar entering the debris collection hopper.

[0024] The screen has 2-3 layers, from the inside out: a coarse screen, a medium screen, and a fine screen. The aperture diameter of each screen is defined as follows: coarse screen aperture diameter > medium screen aperture diameter > fine screen aperture diameter; there is a gap between adjacent screens. Further, the gap between the coarse and medium screens is 2-3 times the aperture diameter of the coarse screen, and the gap between the medium and fine screens is 1.5-2 times the aperture diameter of the medium screen. The significance of the above-mentioned screen design lies in two aspects. Firstly, the screens are spaced apart according to the size of the screen openings, providing material movement space between adjacent screens. This allows materials with larger openings to move freely in front of adjacent screens with smaller openings, greatly preventing material congestion and reducing screen efficiency. Secondly, based on the characteristics of the rotary screen, as the material rotates with the screen body, coupled with the impact of water flow, materials that need to pass through all screens are influenced by water flow and other factors during continuous tumbling and pass through the screens. Undesirable debris, even if it remains between adjacent screens, has the opportunity to return to the screens under the influence of screen rotation and water flow, and is eventually discharged through the screening end of the screen body. Furthermore, in practical operation, multiple conical rotary screens can be installed in series to further reduce debris remaining in the mortar.

[0025] The discharge end of the conical drum screen is located at the bottom of the screen body. Silica sand raw material (fine material) meeting the particle size requirements falls through the outer screen during the screening process. A fine material collection device is used to collect this material and guide it to subsequent processes (such as desliming, washing, etc.). The fine material collection device is typically a hopper located below the screen body, with a discharge port at the bottom, which may be connected to a screw conveyor or chute to transport the material to the next piece of equipment.

[0026] Example 3.

[0027] This embodiment provides a cone-shaped rotary screen with a multi-layer screen structure. Its component composition is the same as or similar to that of the embodiments described above, but the specifications and dimensions of some components are further defined. For example, the feed end diameter is approximately 800mm, the discharge end diameter is approximately 1200mm, and the screen body length is approximately 4000mm. The screen body axis is installed at an angle of 3° to 8° to the horizontal plane. The screen body has two layers of screens from the inside out: the inner screen 21 uses a 20mm x 20mm square mesh screen, mainly used to intercept large debris such as tree branches and large pieces of plastic; the outer screen 22 uses a 5mm x 5mm square mesh screen, used to intercept medium-sized debris and a small amount of excessively coarse sand. Both screens are stamped from high-strength wear-resistant steel plates. Rolling rings and toothed rings are fixed to the outer wall of the screen body.

[0028] Furthermore, in this embodiment, the number of screen layers can be increased to three. An intermediate screen with a mesh size of 10mm x 10mm is added between the innermost layer (inner screen 21, 20mm aperture) and the outermost layer (outer screen 22, 5mm aperture). This three-layer screen structure enables finer grading and removal of impurities. For example, the 20mm screen removes extra-large impurities, the 10mm screen removes medium to large impurities, and the 5mm screen removes small impurities, further improving the pre-screening effect and reducing the burden on subsequent processes.

[0029] Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications and substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A cone-shaped rotating screen with a multi-layer screen structure, characterized in that, The rotary screen includes a shell, a feeding device, a conical drum screen body, and a drive device; The shell is used to construct the supporting structure of the rotary screen and serves as a receiving container for the conical drum screen body; The feeding device is located above the feed end of the conical drum screen body and is used to receive the raw ore from the sand dredger and guide it into the screen body; the feeding device includes a feed chute that extends into the interior of the conical drum screen body to ensure that the material can smoothly enter the conical drum screen body. The conical drum screen body includes a feed end, a discharge end, and a screening end. The conical drum screen body is shaped like a truncated cone, meaning the feed end has a smaller diameter and the screening end has a larger diameter. The axis of the conical drum screen body is installed parallel to the horizontal plane or at a certain angle. The conical drum screen body has at least two coaxially arranged screens from the inside to the outside. When there are two screens, they are an inner screen and an outer screen. The inner screen has a larger mesh size, and the outer screen has a smaller mesh size. The discharge end is located below the conical drum screen body and mainly consists of an inverted conical collecting device located at the bottom of the shell. The drive unit is used to drive the conical drum screen body to rotate around its axis; the drive unit includes a motor, a reducer, and a transmission mechanism, which is implemented by any one of gear transmission, sprocket and chain transmission, or roller friction transmission.

2. The conical rotating screen with a multi-layer screen structure according to claim 1, characterized in that: The conical drum screen body is provided with a rotating shaft, which is assembled on the housing through a bearing seat. At least two sets of screen supports are provided on the rotating shaft, and screen wall frames are provided on the circumferential surface between the screen supports. The screen wall frames are used to construct the outer circumferential contour of the conical drum screen body, and the screen is attached to the screen wall frames.

3. The conical rotary screen with a multi-layer screen structure according to claim 1 or 2, characterized in that: The feeding device includes a buffer well and a feeding pipe. The buffer well is a vertical pipe, and the feeding chute is located on the side of the buffer well. The side of the buffer well has an opening that connects the feeding chute and the buffer well.

4. The cone-shaped rotating screen with a multi-layer screen structure according to claim 3, characterized in that: The upper end of the buffer well is located above the feed chute, and the lower end is flush with the bottom of the shell.

5. The conical rotary screen with a multi-layer screen structure according to any one of claims 1, 2, and 4, characterized in that: The screen has 2-3 layers, from the inside out: coarse screen, medium screen, and fine screen. The screen aperture diameter of each screen is defined as follows: coarse screen aperture diameter > medium screen aperture diameter > fine screen aperture diameter; there is a gap between adjacent screens.

6. The conical rotary screen with a multi-layer screen structure according to claim 5, characterized in that: The spacing between the coarse screen and the medium screen is 2-3 times the diameter of the coarse screen openings.

7. The conical rotary screen with a multi-layer screen structure according to claim 5, characterized in that: The interval between the medium screen and the fine screen is 1.5-2 times the diameter of the screen openings of the medium screen.

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