Powder selecting system for cement grinding
By installing a wind deflector, a labyrinth-type sealing plate, and adjusting the tilt angle of the guide vanes inside the air classifier, the problem of air leakage in cement grinding and air classifying equipment was solved, the separation efficiency was improved, and the equipment life was extended.
Patent Information
- Application Number
- CN202423200277.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-24
- Publication Date
- 2026-02-10
- Estimated Expiration
- 2034-12-24
AI Technical Summary
Existing cement grinding and classifying equipment suffers from air leakage, resulting in low classification efficiency and accelerated wear of the rotor separator.
By installing a wind deflector, a labyrinth-type sealing plate, and adjusting the tilt angle of the guide vanes inside the air classifier, the airflow guidance and ventilation resistance are enhanced, thereby increasing the centrifugal wind speed.
It effectively blocks airflow, improves the separation efficiency of the air classifier, reduces wear, and extends the equipment's lifespan.
Smart Images
Figure CN223888121U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of cement production technology, specifically to a cement grinding and classifying system. Background Technology
[0002] A classifier uses the centrifugal force generated by its high-speed rotating rotor separator to screen materials. Qualified fine materials are discharged from the top of the rotor separator, while coarse materials fall into the grinding mill for further grinding due to gravity.
[0003] Because there is a gap between the rotor separator and the inner wall of the air classifier, there is an air leakage problem. Some airflow escapes directly from the gap without entering the rotor separator, thus reducing the air classification efficiency. Furthermore, with long-term use, the rotor separator itself also experiences wear, which exacerbates the air leakage problem and further reduces the air classification efficiency. Utility Model Content
[0004] (a) Technical problems to be solved
[0005] To address the shortcomings of existing technologies, this utility model provides a cement grinding and classifying system that solves the problem of low classification efficiency in existing cement grinding and classifying equipment.
[0006] (II) Technical Solution
[0007] To achieve the above objectives, the present invention provides the following technical solution: a cement grinding and classifying system, comprising a classifier and a grinding mill, wherein the classifier and the grinding mill are interconnected, a feed chute is provided on one side of the grinding mill, a rotatable grinding disc is provided at the bottom of the grinding mill, a grinding mill nozzle ring is provided around the grinding disc, and multiple air outlets are provided at the top of the grinding mill nozzle ring.
[0008] A rotatable grinding roller is mounted above the grinding disc, and the grinding roller is driven by an external first motor.
[0009] The classifier is equipped with a second motor at the top, and a rotating shaft is installed at the output end of the second motor. Multiple guide vanes are installed on the rotating shaft, and the classifier is equipped with a discharge port at the top.
[0010] The bottom of the inner wall of the air classifier is equipped with a wind baffle, which is located below the rotating shaft.
[0011] As a further preferred embodiment, a first sealing plate and a second sealing plate are respectively provided in the gap between the guide vane and the inner wall of the classifier, and the first sealing plate and the second sealing plate are staggered.
[0012] As a further preferred embodiment, the first sealing sheet is inclined downwards and the second sealing sheet is inclined upwards.
[0013] As a further preferred embodiment, a cleaning brush is provided at the top of the rotating shaft, and the bristles of the cleaning brush are in contact with the inner wall of the powder classifier.
[0014] As a further preferred embodiment, the included angle α between the guide vane and the axis of rotation is 15-20 degrees.
[0015] As a further preferred embodiment, a V-shaped feed hopper is provided in the middle of the inner wall of the grinding mill, and the V-shaped feed hopper is located directly below the rotating shaft.
[0016] (III) Beneficial Effects
[0017] This utility model provides a cement grinding and classifying system. It has the following beneficial effects:
[0018] This cement grinding and classifying system solves the air leakage problem through three steps. First, by installing a baffle at the bottom of the guide vanes, the arc shape of the baffle can block airflow from entering the gap and guide more airflow into the interior of the guide vanes. Second, by installing a labyrinth-shaped sealing plate in the gap, the ventilation resistance in the gap is increased, thereby blocking airflow from flowing through the gap and allowing more airflow to concentrate into the guide vanes. Third, by adjusting the tilt angle of the guide vanes, increasing the tilt angle to 15-20 degrees, the centrifugal wind speed inside the guide vanes can be increased, thereby improving the separation efficiency of the classifier. Attached Figure Description
[0019] Figure 1 This is a schematic diagram of the first embodiment of the present utility model;
[0020] Figure 2 This is a schematic diagram of the second embodiment of the present utility model;
[0021] Figure 3 This is a top view of the mill nozzle ring structure of this utility model;
[0022] Figure 4 This is a top view of the guide vane structure of this utility model.
[0023] In the diagram: 1. Air classifier; 2. Grinding mill; 3. Feed chute; 4. Grinding disc; 5. Grinding roller; 6. First motor; 7. Mill nozzle ring; 8. Air outlet; 9. Second motor; 10. Rotating shaft; 11. Guide vane; 12. Discharge port; 13. Wind shield; 14. First sealing plate; 15. Second sealing plate; 16. Cleaning brush; 17. V-shaped feed hopper. Detailed Implementation
[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0025] like Figure 1-4 As shown, this utility model provides a technical solution: a cement grinding and classifying system, including a classifier 1 and a grinding mill 2. The classifier 1 and the grinding mill 2 are interconnected. A feed chute 3 is provided on one side of the grinding mill 2. A rotatable grinding disc 4 (driven by an external motor) is provided at the bottom of the grinding mill 2. A grinding mill nozzle ring 7 (supplying air by an external fan) is provided around the grinding disc 4. Multiple air outlets 8 are opened on the top of the grinding mill nozzle ring 7.
[0026] A rotatable grinding roller 5 is provided above the grinding disc 4. The grinding roller 5 is driven by an external first motor 6. The grinding roller 5 is slightly inclined towards the middle. The material falls directly into the middle of the grinding disc 4. After being ground by the grinding roller 5, it is thrown to the four sides by the centrifugal rotation of the grinding disc 4.
[0027] A second motor 9 is installed at the top of the classifier 1. A rotor separator is installed at the output end of the second motor 9. The rotor separator includes a rotating shaft 10 and multiple guide vanes 11. Multiple guide vanes 11 are installed on the rotating shaft 10. The angle α between the guide vanes 11 and the axis of the rotating shaft 10 is 15-20 degrees. The original tilt angle of the guide vanes 11 is generally around 10 degrees. After being enlarged, the centrifugal wind speed can be increased. A discharge port 12 is installed at the top of the classifier 1.
[0028] A cleaning brush 16 is provided on the top of the rotating shaft 10. The bristles of the cleaning brush 16 contact the inner wall of the classifier 1. When the rotating shaft 10 rotates, it drives the cleaning brush 16 to rotate, thereby cleaning the inner wall of the classifier 1 and preventing skin from forming.
[0029] A wind baffle 13 is provided at the bottom of the inner wall of the air classifier 1. The wind baffle 13 is located below the rotating shaft 10 and can prevent airflow from entering the gap.
[0030] A V-shaped hopper 17 is provided in the middle of the inner wall of the grinding mill 2. The V-shaped hopper 17 is located directly below the rotating shaft 10. The hopper is wider at the top and narrower at the bottom, which can prevent airflow from entering the central area of the rotating shaft 10, thereby facilitating the coarse material to fall from the central area into the grinding disc 4.
[0031] Figure 1 The direction of the middle arrow indicates the direction of airflow.
[0032] A first sealing plate 14 and a second sealing plate 15 are respectively provided in the gap between the guide vane 11 and the inner wall of the classifier 1. The first sealing plate 14 and the second sealing plate 15 are staggered. The first sealing plate 14 is inclined downward and the second sealing plate 15 is inclined upward.
[0033] Regarding the distribution of the first sealing plate 14 and the second sealing plate 15, we provide two options (not limited to these two options), see attached. Figure 1 In this configuration, the first sealing plate 14 and the second sealing plate 15 are arranged in parallel, and the airflow continuously shuttles between the first sealing plate 14 and the second sealing plate 15. During this process, the airflow is continuously blocked by the sealing plates, but the material carried by the airflow is easily adsorbed within the angle between the first sealing plate 14 and the inner wall. Therefore, as shown in the attached... Figure 2 As shown, the first sealing sheet 14 and the second sealing sheet 15 are distributed opposite to each other. Under the action of airflow, the material can wash against the first sealing sheet 14 and the second sealing sheet 15 to avoid material accumulation.
[0034] Furthermore, any content not described in detail in this specification is existing technology known to those skilled in the art.
[0035] In operation, cement material enters the grinding mill 2 through the feed chute 3 and falls onto the grinding disc 4 below. The grinding disc 4 is driven to rotate by an external motor. When the first motor 6 is turned on, it can drive the grinding roller 5 to rotate, thereby grinding the cement material on the grinding disc 4. During the centrifugal rotation of the grinding disc 4, the ground cement material is thrown above the mill nozzle ring 7. The mill nozzle ring 7 is connected to high-pressure gas, which is blown out from the air outlet 8, blowing the cement material into the classifier 1. The material in the mill is sent to the upper classifier 1 in a gas-solid mixed state.
[0036] The material enters the rotor separator of the classifier 1. The rotation of the shaft 10 and the action of the guide vanes 11 (angle 15°) create a high-speed centrifugal wind inside, which sorts the material carried in the gas. The high-speed rotating centrifugal wind separates the coarse and fine particles in the material. The finished fine particles rise with the airflow and are discharged through the discharge port 12, while the coarse particles gather in the lower part of the classifier 1 and fall back to the grinding disc 4 for further grinding due to their own gravity.
[0037] In summary, this cement grinding and classifying system solves the air leakage problem through three steps: First, by installing a baffle at the bottom of the guide vanes, the arc shape of the baffle can block airflow from entering the gap area and guide more airflow into the guide vanes; Second, by installing a labyrinth-shaped sealing plate in the gap area, the ventilation resistance within the gap is increased, thereby blocking airflow from flowing through the gap and allowing more airflow to concentrate into the guide vanes; Third, by adjusting the tilt angle of the guide vanes, increasing the tilt angle to 15-20 degrees, the centrifugal wind speed inside the guide vanes can be increased, thereby improving the separation efficiency of the classifier.
[0038] It should be noted that all electrical components mentioned in this article are electrically connected to an external main controller and 220V or 380V AC mains power. The main controller can be a conventional, known device such as a computer, and its control principles, internal structure, and control switching methods are all conventional methods of existing technology. These are directly cited here without further elaboration. In this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus.
[0039] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A cement grinding and classifying system, characterized in that: It includes a classifier (1) and a grinding mill (2). The classifier (1) and the grinding mill (2) are interconnected. A feed chute (3) is provided on one side of the grinding mill (2). A rotatable grinding disc (4) is provided at the bottom of the grinding mill (2). A mill nozzle ring (7) is provided around the grinding disc (4). Multiple air outlets (8) are provided on the top of the mill nozzle ring (7). A rotatable grinding roller (5) is provided above the grinding disc (4), which is driven by an external first motor (6); A second motor (9) is installed on the top of the classifier (1), and a rotating shaft (10) is installed at the output end of the second motor (9). Multiple guide vanes (11) are installed on the rotating shaft (10), and a discharge port (12) is installed on the top of the classifier (1). A wind deflector (13) is provided at the bottom of the inner wall of the air classifier (1), and the wind deflector (13) is located below the rotating shaft (10).
2. The cement grinding and classifying system according to claim 1, characterized in that: A first sealing plate (14) and a second sealing plate (15) are respectively provided in the gap between the guide vane (11) and the inner wall of the classifier (1), and the first sealing plate (14) and the second sealing plate (15) are staggered.
3. A cement grinding and classifying system according to claim 2, characterized in that: The first sealing sheet (14) is inclined downwards, and the second sealing sheet (15) is inclined upwards.
4. The cement grinding and classifying system according to claim 1, characterized in that: A cleaning brush (16) is provided on the top of the rotating shaft (10), and the bristles of the cleaning brush (16) are in contact with the inner wall of the powder classifier (1).
5. A cement grinding and classifying system according to claim 1, characterized in that: The included angle α between the guide vane (11) and the axis of rotation (10) is 15-20 degrees.
6. A cement grinding and classifying system according to claim 1, characterized in that: The grinding mill (2) has a V-shaped hopper (17) in the middle of its inner wall, which is located directly below the rotating shaft (10).