Spiral lining plate and vertical roller grinding stone mill
By using spiral liners in wet vertical mills, the problem of excessive grinding of fine particles in wet vertical mills is solved, achieving efficient classification and grinding of materials, improving equipment operation stability and grinding efficiency, and reducing energy consumption.
Patent Information
- Application Number
- CN202511399359.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-28
- Publication Date
- 2026-01-27
AI Technical Summary
Existing wet vertical mills lack an effective classification mechanism, resulting in over-grinding of fine particles, low grinding efficiency, high power consumption, and unstable equipment operation, which affects production continuity and equipment safety.
It adopts a spiral liner, designed as a disc with a circumferential spiral structure on the upper disc surface, forming a continuous and gradually changing height difference. It uses gravity, water flow and centrifugal force to classify coarse and fine materials, and achieves self-classification of materials through the spiral path and water flow.
It achieves natural separation and dynamic classification of materials inside the mill, improves grinding efficiency, reduces power consumption, improves mill condition, extends equipment life, and has a simple structure and strong adaptability.
Smart Images
Figure CN121402187A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of grinding equipment technology, and particularly relates to a spiral liner and a vertical roller mill for ore grinding. Background Technology
[0002] In existing dry vertical mill designs, the liners on the grinding disc are typically arranged at equal height along the circumference, lacking a height difference structure. Dry vertical mills often employ an air-swept structure, where fine particles generated during grinding are promptly carried out of the mill by airflow, while coarse particles remain on the grinding disc for repeated grinding until their size is small enough to be carried away by the airflow, thus achieving a certain degree of in-mill self-circulation and classification. However, in wet grinding processes, due to the absence of an airflow classification mechanism within the mill, fine particles cannot be discharged by airflow and must rely on water flow for material transport and separation. Because the material is in a slurry state under wet conditions, coarse and fine particles flow together with water, lacking effective particle classification methods. This characteristic adversely affects grinding efficiency and product quality.
[0003] In existing wet vertical mill technology, due to the difficulty in effectively separating coarse and fine particles in the slurry state, a large number of fine particles that have reached the required grinding fineness often cannot be discharged with the water in time. Instead, they are carried by coarse particles and re-enter the grinding zone to participate in grinding, causing severe over-grinding. This not only reduces grinding efficiency and increases power consumption per unit capacity, but also causes the material layer to thicken and the grinding conditions to become disordered due to the continuous retention and accumulation of fine particles on the grinding disc. This can lead to high-frequency vibration or even equipment shutdown and other operational instability problems, seriously affecting the continuity of production and the safety of the equipment. Therefore, existing wet vertical mills still have significant shortcomings in terms of structure and process, and there is an urgent need to optimize and improve the material separation and discharge mechanism. Summary of the Invention
[0004] In view of the technical problems of existing wet vertical mills, such as excessive grinding of fine particles, low grinding efficiency, high power consumption and unstable equipment operation due to the lack of an effective classification mechanism, this invention provides a spiral liner and a vertical roller mill for ore grinding.
[0005] The present invention is implemented as follows: a spiral liner, characterized in that: the spiral liner is placed on the upper surface of a grinding disc, the spiral liner is constructed in the shape of a disc and the upper surface of the disc has a circumferential spiral structure, and the spiral structure forms a continuously gradually changing height difference in the circumferential direction.
[0006] In the above technical solution, preferably, the integral liner is composed of an annular spiral portion and a transition portion, wherein the annular spiral portion is configured into a circumferential spiral structure, and the transition portion forms a height difference that is continuously and gradually changed in the opposite direction to the annular spiral portion.
[0007] In the above technical solution, preferably, the helix angle of the spiral structure of the liner is... Satisfying the relation:
[0008] Wherein, P is the pitch and R is the helical radius, and the pitch P is 1.5-2 times the thickness of the mill material layer.
[0009] In the above technical solution, preferably, the liner of the closed-loop structure is composed of liner units evenly distributed in the circumferential direction.
[0010] In the above technical solution, preferably, the transition portion is constructed in one of the liner units, and the remaining liner units are collectively constructed to form the annular spiral portion.
[0011] In the above technical solution, preferably, the transition portion formed by the liner unit forms a continuously and gradually changing height difference.
[0012] In the above technical solution, preferably, the liner drives the material to move along the spiral path to the outside of the grinding disc, and achieves self-grading of coarse and fine materials through centrifugal force and water flow.
[0013] The spiral liner proposed in this invention has several significant advantages and technical effects, and is suitable for bed-type grinding equipment such as wet vertical mills. It is particularly suitable for situations where there is mixing of coarse and fine particles and over-grinding is prone to occur. Its advantages and effects can be described in detail from the following aspects: First, the mill achieves self-grading of materials within the mill. The spiral liner's disc surface is constructed with a continuous height difference in a circumferential spiral structure, causing the material to undergo radial and tangential combined motion as it rotates with the grinding disc. Under the combined action of gravity, water flow, and centrifugal force, materials of different particle sizes experience different adhesion forces and hydrodynamic forces due to their mass differences. Fine particles have lower friction and adhesion forces with the liner and are more easily carried away from the mill by the water flow; while larger coarse particles, due to greater inertia and friction, are difficult to be discharged with the water flow and remain attached to the liner, being carried to the bottom of the grinding roller for further grinding. This achieves natural separation and dynamic grading of coarse and fine materials within the mill. This grading mechanism, based on the coupling effect of structural guidance and fluid mechanics, effectively avoids the repeated grinding of fine particles and improves the concentration of product particle distribution.
[0014] Secondly, it improves grinding efficiency per unit time. Because the spiral liners create a height difference in the circumferential direction, the contact surface (i.e., the meshing surface) between the grinding disc and the grinding roller changes from a traditional horizontal plane to an inclined surface. This increases the grinding contact angle and contact area, significantly increasing the amount of material entering the stress zone below the grinding roller per unit time. This structure enhances the compaction of the material layer, which is beneficial for increasing the amount of material crushed per unit time, thereby improving overall grinding efficiency. Furthermore, the "spiral climbing path" formed by the inclined structure also extends the residence time of the material on the grinding disc, allowing coarse particles to have more sufficient grinding opportunities, helping to control the finished particle size and reduce coarse particle inclusions.
[0015] Third, it reduces energy consumption, improves grinding conditions, and extends equipment life. The spiral liner design allows qualified fine particles to be discharged from the mill promptly, reducing ineffective circulation and preventing over-grinding caused by particle accumulation. This structure, without relying on air sweeping, achieves efficient material control through a combination of water flow guidance and structural grading, thereby reducing power consumption per unit product. Furthermore, with the timely discharge of fine particles, the material layer thickness inside the mill is more reasonable, and the grinding conditions are more stable, helping to reduce the frequency of high-frequency vibrations, significantly reducing the risk of equipment shutdown, and extending the service life of key components such as rollers, bearings, and grinding disc liners.
[0016] Finally, the structure is simple to implement, highly maintainable, and widely adaptable. The spiral liner is formed by assembling multiple standardized liner units along a circumferential direction. A continuous spiral profile is achieved through a height variation design, facilitating manufacturing and replacement, and reducing maintenance costs. It is suitable for different types of wet grinding equipment, especially in mill environments with no air sweeping structure, where its unique structural advantages are particularly prominent. Furthermore, the spiral angle and height difference can be flexibly adjusted according to factors such as material properties, feed particle size, and mill speed to adapt to different grinding conditions, demonstrating good versatility and promising industrial application prospects.
[0017] In summary, the spiral liner provided by this invention breaks through the limitations of traditional horizontal liners in terms of structural design, integrating advantages such as self-grading, high efficiency, low energy consumption, and low failure rate. It is a key improved component suitable for wet bed grinding systems and has significant promotional value and industrial application prospects.
[0018] The second objective of this invention is to provide a vertical roller mill for ore grinding, comprising a grinding disc and a rocker arm grinding roller mechanism, characterized in that: a liner plate as described in any one of claims 1-7 is installed on the upper surface of the grinding disc, and a grinding angle for grinding materials is formed between the grinding roller of the rocker arm grinding roller mechanism and the upper surface of the liner plate.
[0019] In the above technical solution, preferably, the liner is fixed to the surface of the grinding disc by mechanical connection to form a continuous spiral climbing surface.
[0020] In the above technical solution, preferably, the spiral structure of the liner is configured such that when the grinding roller of the rocker arm grinding roller mechanism contacts the liner, the grinding angle formed by the two is located at the lower position of the angle between the two sides of the grinding roller. Attached Figure Description
[0021] Figure 1 This is a schematic diagram of the structure of the liner plate described in this invention; Figure 2 This is a comparative schematic diagram of existing liners and the liners proposed in this application. Detailed Implementation
[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.
[0023] To address the technical problems of existing wet vertical mills, such as excessive grinding of fine particles, low grinding efficiency, high power consumption, and unstable equipment operation due to the lack of an effective classification mechanism, this invention provides a spiral liner and a vertical roller mill for ore grinding. To further illustrate the structure of this invention, a detailed description is provided below in conjunction with the accompanying drawings: Please see Figure 1 A spiral liner is disclosed, comprising a disk-shaped structure with a circumferential spiral structure on the upper surface, the spiral structure creating a continuously varying height difference along the circumference. Specifically, the integral liner consists of an annular spiral portion 1 and a transition portion 2. The annular spiral portion is constructed with a circumferential spiral structure, and the transition portion creates a continuously varying height difference in the opposite direction to the annular spiral portion. The closed-loop liner is composed of circumferentially distributed liner units. The transition portion is constructed in one liner unit, and the remaining liner units together form the annular spiral portion. The transition portion formed by the liner units creates a continuously varying height difference.
[0024] This spiral liner is suitable for roller mills or other rotary grinding devices. The liner is disc-shaped and installed on the upper surface of the mill disc to help achieve stable material layer formation and efficient grinding. The spiral structure of the upper disc of the spiral liner creates a continuous and gradually changing height difference in the circumferential direction, thereby controlling the movement of the material along the spiral path during the rotation of the mill disc, thus improving grinding uniformity and efficiency.
[0025] Specifically, the spiral liner is composed of multiple liner units evenly distributed along the circumference, which are assembled to form an integral closed-loop disc structure. Each liner unit is a fan-shaped plate with a certain curvature along the circumferential direction to match the rotation trajectory of the grinding disc. Structurally, the liner includes two regions: an annular spiral section and a transition section. The majority of the section forms the annular spiral section, which is constructed with a spiral structure extending circumferentially. The height of the spiral structure gradually increases or decreases from one end to the other, forming a continuously varying inclined surface. The transition section is located on at least one of the liner units, forming the start and end transition area of the spiral structure. Its height change direction is opposite to that of the spiral section, forming a structure that connects with the continuously varying height of the spiral section. This results in a closed, smoothly transitioning annular spiral profile, thus ensuring mechanical continuity while avoiding local stress concentration or material accumulation.
[0026] To facilitate replacement and maintenance, the liner units are detachably assembled using bolt connections, dovetail grooves, locating pin holes, or other mechanical connection structures, forming a closed and continuous disc surface after installation.
[0027] Example 2 A vertical roller mill for ore grinding includes a grinding disc and a rocker arm grinding roller mechanism. The aforementioned liner is installed on the upper surface of the grinding disc, and a grinding angle for grinding materials is formed between the grinding roller of the rocker arm grinding roller mechanism and the upper surface of the liner.
[0028] The liner is mechanically fixed to the surface of the grinding disc, forming a continuous spiral climbing surface. The spiral structure of the liner is configured such that when the grinding rollers of the rocker arm grinding roller mechanism contact the liner, the included grinding angle formed between them is located at the lower of the included angles on both sides of the grinding rollers. The liner drives the material to move along the spiral path towards the outside of the grinding disc, and achieves self-classification of coarse and fine materials through centrifugal force and water flow.
[0029] The spiral structure of the spiral liner creates a continuous, gradually varying height difference along the circumference. This design not only helps guide the circumferential and radial flow of materials but also has a significant effect on material classification. Due to the significant differences in particle size and mass between coarse and fine materials, the adhesion and fluid scouring forces they experience on the grinding disc surface also differ. Coarse particles, due to their large mass and high inertia, experience less water flow and are more easily adhered to the grinding disc liner surface, moving in a circular motion with the grinding disc. Fine particles, on the other hand, due to their small size and light weight, have relatively weak adhesion to the liner and are more easily carried away from the mill by water flow and centrifugal force, quickly entering the next classification or separation process. It is precisely because the spiral liner introduces a height difference in its structure that the segregation effect on coarse and fine particles is enhanced as water flows along the spiral structure, achieving the initial classification function of materials within the mill. This helps improve the classification accuracy and grinding efficiency of the entire machine.
[0030] Meanwhile, because the spiral liner creates an inclined surface on the meshing surface between the grinding disc and the grinding roller, the meshing angle is increased compared to the traditional horizontally arranged liner structure in the circumferential direction. Figure 2 This increases the amount of material entering the grinding rollers per unit time for compaction and grinding, resulting in a thicker compacted material bed and enhanced bed strength, which is beneficial for effective crushing. Combining the principle of "multi-layer crushing" in bed grinding, this structure allows coarse particles to be efficiently compressed while covered by fine particles, facilitating thorough crushing of coarse particles, thereby improving overall grinding efficiency, reducing unit energy consumption, and extending equipment life.
[0031] In summary, the spiral liner, through its unique structural design, not only achieves the function of material conveying but also has the dual technical effects of enhancing particle classification and improving grinding efficiency. It is an important improvement over the traditional horizontal liner structure, and has significant technological progress and broad prospects for industrial application.
[0032] The helix angle of the spiral structure of the liner satisfies the following relationship:
[0033] Where P is the pitch and R is the helix radius, and the pitch P is 1.5-2 times the thickness of the mill material layer.
[0034] Force analysis: Tangential component (along the direction of helical motion): Fg 切 =mgsinα,Fc 切 =Fc cosα=mRω2cosα Normal force (perpendicular to the liner direction): N=mgcosα+Fcsinα=m(gcosα+Rω2sinα) Friction: F f =μN=μm(gcosα+Rω2sinα) in: ω is the angular velocity (rad / s), t is the time parameter (s), ω c The critical angular velocity is (rad / s). The helix angle is rad, and the gravitational force F is... g =mg, normal force N, frictional force F f =μN, centrifugal force F c =mRω 2 , Critical angular velocity ω c : ω c=
[0035] Parameterized trajectory equation of the helix: ω≥ωc The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. A spiral liner, characterized in that: The spiral liner is placed on the upper surface of the grinding disc. The spiral liner is constructed in the shape of a disc and the upper surface has a circumferential spiral structure. The spiral structure forms a continuous and gradually changing height difference in the circumferential direction.
2. The spiral liner according to claim 1, characterized in that: The integral liner consists of an annular spiral section and a transition section. The annular spiral section is configured into a circumferential spiral structure, and the transition section forms a height difference that is continuously and gradually changed in the opposite direction to the annular spiral section.
3. The spiral liner according to claim 2, characterized in that: The spiral angle of the spiral structure of the liner Satisfying the relation: Wherein, P is the pitch and R is the helical radius, and the pitch P is 1.5-2 times the thickness of the mill material layer.
4. The spiral liner according to claim 3, characterized in that: The liner in the closed-loop structure is composed of liner units evenly distributed in the circumferential direction.
5. The spiral liner according to claim 4, characterized in that: The transition portion is constructed on one of the liner units, and the remaining liner units together form the annular spiral portion.
6. The spiral liner according to claim 5, characterized in that: The transition section formed by the liner unit creates a continuously varying height difference.
7. The spiral liner according to claim 6, characterized in that: The liner drives the material to move along the spiral path to the outside of the grinding disc, and achieves self-grading of coarse and fine materials through centrifugal force and water flow.
8. A vertical roller mill for ore grinding, comprising a grinding disc and a rocker arm roller mechanism, characterized in that: The upper surface of the grinding disc is equipped with a liner plate as described in any one of claims 1-7, and a grinding angle for grinding materials is formed between the grinding roller of the rocker arm grinding roller mechanism and the upper surface of the liner plate.
9. The vertical roller mill for ore according to claim 8, characterized in that: The liner is fixed to the surface of the grinding disc by mechanical connection, forming a continuous spiral climbing surface.
10. The vertical roller mill for ore according to claim 9, characterized in that: The spiral structure of the liner is configured such that when the grinding roller of the rocker arm grinding roller mechanism contacts the liner, the grinding angle formed by the two is located at the lower position of the angle between the two sides of the grinding roller.