A vertical roller mill with both the main roller and the auxiliary roller being driving members and a design method thereof

Abstract

The application provides a vertical roller mill with main rollers and auxiliary rollers being driving members and a design method thereof, the vertical roller mill comprising a plurality of main rollers, each of the main rollers corresponding to an auxiliary roller; the main rollers and the auxiliary rollers are drivingly rotated to mill materials on a millstone; main parameters of the vertical roller mill are determined: total installed power is determined according to material characteristics, mill design table output, finished product characteristics and a design method for conventional mill selection. The main rollers and the auxiliary rollers are drivingly rotated, and friction of the main rollers to the materials drives the millstone. A two-stage planetary transmission mechanism is adopted in a driving device of the main roller, which improves transmission efficiency and guarantees a large torque and a more compact structure. More mill rollers can be arranged on a millstone, which is beneficial to further improvement of mill capacity. In the design of the vertical roller mill, a plurality of parameters such as material characteristics are comprehensively considered for reasonable design, so that the vertical roller mill reaches the best grinding efficiency and energy consumption and cost are reduced.

Description

Technical Field

[0001] This invention relates to the field of vertical roller mill equipment, and more specifically to a vertical roller mill in which both the main roller and the auxiliary roller are actively rotating components, and its design method. Background Technology

[0002] Vertical roller mills are grinding equipment that integrates grinding, drying, and powder selection, and are widely used in grinding various materials such as cement, raw materials, and coal powder. However, in recent years, with the technological advancements in roller presses, the power consumption of roller presses for grinding raw materials is significantly lower than that of vertical roller mills. Generally, when grinding the same material, the main power consumption of a vertical roller mill is about 0.8 kWh / t higher than that of a roller press, resulting in a significant decrease in the competitiveness of vertical roller mills.

[0003] From a grinding mechanism perspective, both vertical roller mills and roller presses are bed grinding processes. However, vertical roller mills suffer from poor controllability of the material layer, relying solely on retaining rings to adjust the stability of the material layer and grinding efficiency. Increasing the retaining rings thickens the material layer, leading to lower grinding efficiency; decreasing the retaining rings thins the material layer, increasing grinding efficiency but causing greater mill vibration. Roller presses, on the other hand, use two opposing and synchronously rotating rollers. The material is actively bitten into the grinding zone by the frictional force of the two actively rotating rollers, resulting in better stability than vertical roller mills. Therefore, larger roller pressures can be used, leading to higher grinding efficiency. In contrast, existing vertical roller mills rely on the active rotation of the grinding disc. The material on the disc generates friction against the rollers, which rotate passively. Material accumulation at the feed front of the rollers is unavoidable, especially with thicker material layers. This accumulation disrupts the stability of the material layer, increasing mill vibration and hindering the application of roller pressure. Consequently, the grinding efficiency is lower than that of roller presses, and the power consumption per unit is higher.

[0004] The scaling up of vertical mills requires larger motor power and higher reducer torque. The challenge lies in the increased manufacturing difficulty of high-power motors and reducers, especially the large spiral bevel, which significantly increases costs. Grinding different materials in the same vertical mill necessitates adjusting the grinding disc speed; however, manufacturing frequency converters for high-power motors is extremely difficult, so the motors are typically kept at a constant speed. This results in lower adaptability of vertical mills for grinding a variety of materials.

[0005] Chinese Patent Publication No. CN117427732A discloses a vertical roller mill driven by a grinding roller and its grinding method, which belongs to the field of vertical roller mill equipment. However, this patent adopts a single-stage planetary structure, which has low transmission efficiency and limited adjustment range of reduction ratio, thus limiting the improvement of the grinding capacity of the vertical roller mill.

[0006] Chinese Patent No. CN114653436A discloses a grinding device driven by an auxiliary roller, comprising a transmission assembly, an auxiliary roller assembly, a rocker arm assembly, and a pressurizing assembly. The auxiliary roller assembly is fixed in the rocker arm via a hollow shaft and a grinding roller expansion sleeve. The rocker arm assembly is fixedly connected to a connecting bridge. The auxiliary roller motor in the transmission assembly is connected to a transmission shaft via a coupling. The transmission shaft is connected to a cap via a key. The cap is connected to a hub via a reamed bolt. The roller sleeve is fixed to the hub via a T-bolt and a pressure ring. The pressurizing assembly uses two hydraulic cylinders for loading. The lower pin of the cylinder is connected to the middle housing. The upper pin of the cylinder is connected to the upper ear of the rocker arm. The hydraulic cylinder pull causes the auxiliary roller to rotate around the rocker arm shaft, compacting and grinding the material on the grinding disc. The patent does not disclose how to reasonably design the parameters of the vertical roller mill. There may be a large space between two adjacent grinding rollers on the grinding disc. Some materials fall off the grinding disc without being ground. The material stays on the grinding disc for a short time, making it difficult to be fully ground, which reduces grinding efficiency. Moreover, an unreasonable design may also lead to high energy consumption and increased costs. Summary of the Invention

[0007] This invention provides a vertical roller mill in which both the main roller and the auxiliary roller are actively rotating components, and its design method, to solve the problems of unstable material layer, limited adjustment range of reduction ratio, difficulty in improving the grinding capacity of vertical roller mills, and high energy consumption and increased cost caused by unreasonable design in the prior art.

[0008] This invention provides a design method for a vertical roller mill in which both the main roller and the auxiliary roller are actively rotating components. The vertical roller mill includes multiple main rollers and multiple auxiliary rollers, with each main roller corresponding to one auxiliary roller. Both the main rollers and the auxiliary rollers actively rotate to grind the material on the grinding disc.

[0009] Determine the main parameters of the vertical roller mill:

[0010] Based on material characteristics, mill design hourly output, and finished product characteristic parameters, the total installed power P is determined with reference to conventional mill selection design methods; the mill design hourly output refers to the total amount of work completed by the designed mill in one hour;

[0011] Power P of each of the main rollers M The ratio of the total installed power P to the total number of grinding rollers n is 0.82 to 0.9 times; the auxiliary roller power P of each auxiliary roller is... S The ratio of the total installed power P to the total number of grinding rollers n is 0.1 to 0.18 times; n1 is the number of main rollers, n2 is the number of auxiliary rollers, and n1 = n2; the power P of the main rollers is... M The unit of the total installed power P is W;

[0012] The grinding disc rotation speed n T The characteristic coefficient K of the material is determined, and the calculation formula is as follows:

[0013] n T =k / D T 0.5 (1)

[0014] In formula (1), the value of K ranges from 52 to 58; the grinding disc rotation speed n T The unit is m / s;

[0015] The rotational speed n of the main roller M According to the diameter D of the grinding disc T Main roller width B M Main roller diameter D M and grinding disc rotation speed n T Confirmed, the calculation formula is as follows:

[0016] n M =(D T -B M ) / D M n T (2)

[0017] In formula (2), the rotational speed n of the main roller is... M and the grinding disc rotation speed n T The unit is m / s, and the diameter D of the grinding disc is... T The width B of the main roller M Main roller diameter D M The unit is m;

[0018] The rotational speed n of the auxiliary roller S According to the diameter D of the grinding disc T Auxiliary roller width B S Auxiliary roller diameter D S and grinding disc rotation speed n T Confirmed, the calculation formula is as follows:

[0019] n S =(D T -B S ) / D S n T (3)

[0020] In formula (3), the rotational speed n of the auxiliary roller is... S The unit is m / s, and the width B of the auxiliary roller is... S Auxiliary roller diameter D S The unit is m;

[0021] In formulas (2) and (3), n M Value is 40-50 rpm, n S The value should be between 50 and 70 rpm.

[0022] The ratio of the roller disk area A of the main roller is calculated using the following formula:

[0023] A = n1D M B M / (1 / 4πD T 2 (4)

[0024] The ratio of the auxiliary roller's disc area B is calculated using the following formula:

[0025] B = n²D S B S / (1 / 4πD T 2 (5)

[0026] The ratio of the roller disk area to A of the main roller is in the range of 0.22 to 0.32;

[0027] The ratio of the area of ​​the auxiliary roller to B is in the range of 0.12 to 0.24.

[0028] The ratio of the roller area ratio A to the roller area ratio B is in the range of 1.5 to 2.

[0029] The width B of the main roller M With the diameter D of the main roller M The ratio ranges from 0.22 to 0.34;

[0030] The width B of the auxiliary roller S With the auxiliary roller diameter D S The ratio ranges from 0.32 to 0.44;

[0031] The gap S between the main roller and the grinding disc liner M S M The value range is 30-60mm, and the gap between the auxiliary roller and the grinding disc liner is the same as the gap S between the main roller and the grinding disc liner. M 1.5 to 2 times;

[0032] The area of ​​the pre-compression crushing zone of the auxiliary roller is smaller than the area of ​​the grinding zone of the main roller, and the outer diameter of the grinding zone is larger than the outer diameter of the pre-compression crushing zone.

[0033] The distance C between the main roller and the retaining ring M The distance C between the auxiliary roller and the retaining ring S The distance between the main roller and the retaining ring is C. MThe diameter of the main roller is 2 to 3 times that of the grinding disc; the height of the retaining ring is H1, which is 0.05 to 0.15 times the diameter of the grinding disc; the liner plate near the retaining ring has a groove with a groove depth H2 and a groove width L1, where the groove depth H2 is 0.1 to 0.2 times the height of the retaining ring and the groove width L1 is 2 times the groove depth H2; the distance C between the main roller and the retaining ring is... M The distance C between the auxiliary roller and the retaining ring S The unit for the height H1 of the retaining ring, the depth H2 of the groove, and the width L1 of the groove is mm.

[0034] The present invention also provides a vertical roller mill in which both the main roller and the auxiliary roller are actively rotating components. The vertical roller mill is manufactured using the design method described in the present invention. The vertical roller mill includes multiple main grinding devices and multiple auxiliary grinding devices of the same number, as well as a grinding disc.

[0035] The main grinding device includes a main roller, a main drive unit, a main pressurizing assembly, and a main rocker arm assembly; each main roller is correspondingly provided with a main drive unit, a main pressurizing assembly, and a main rocker arm assembly. The main drive unit includes a main roller motor, a main roller coupling, a main roller drive shaft, and a secondary planetary transmission mechanism connected in sequence; the main rocker arm assembly and the main pressurizing assembly are located below the corresponding main roller, and the main rocker arm assembly is located between the main pressurizing assembly and the corresponding main roller.

[0036] The auxiliary grinding device includes an auxiliary roller, an auxiliary drive device, an auxiliary pressurizing assembly, and an auxiliary rocker arm assembly; the main roller and the auxiliary roller are located inside the grinding shell and are staggered circumferentially distributed on the grinding disc; the main roller and the auxiliary roller respectively form a grinding zone and a pre-compression crushing zone on the grinding disc, and the gap between the auxiliary roller and the liner plate on the grinding disc is greater than the gap between the main roller and the liner plate on the grinding disc; the rotation of the main roller and the auxiliary roller generates frictional force on the material on the grinding disc, and the frictional force is transmitted to the grinding disc through the material, causing the grinding disc to rotate passively;

[0037] Each auxiliary roller is provided with an auxiliary drive device, an auxiliary pressurizing component, and an auxiliary rocker arm component. The auxiliary drive device includes an auxiliary roller motor, an auxiliary roller drive shaft, and an auxiliary roller planetary gear mechanism connected in sequence. The auxiliary rocker arm component and the auxiliary pressurizing component are located above the corresponding auxiliary roller, and the auxiliary pressurizing component is fixedly connected to the outer side of the grinding shell.

[0038] Optionally, the bottom of the grinding disc is rotatably fixed to the grinding disc support frame by a grinding disc self-aligning bearing and a grinding disc thrust bearing.

[0039] Optionally, both the main roller motor and the auxiliary roller motor are adjustable speed motors, which can adjust the rotational speed of the main roller and the auxiliary roller respectively.

[0040] Optionally, the main grinding device further includes a main roller shaft and a bracket for supporting the main rocker arm assembly;

[0041] The main roller drive shaft is rotatably fixed inside the main roller shaft;

[0042] One end of the main rocker arm assembly is fixed to the outer surface of the main roller shaft, and the other end of the main rocker arm assembly is fixed to the bracket;

[0043] The two adjacent supports are connected by a connecting bridge.

[0044] Optionally, the vertical roller mill further includes an auxiliary roller shaft;

[0045] The auxiliary roller drive shaft is rotatably fixed inside the auxiliary roller shaft;

[0046] The auxiliary rocker arm assembly is fixed in the middle to the outer surface of the auxiliary roller shaft; the first end of the auxiliary rocker arm assembly is hinged to the auxiliary pressurizing assembly, and the second end of the rocker arm assembly is hinged to the rocker arm support on the connecting bridge.

[0047] Optionally, in each of the main grinding devices, the main roller is rotatably fixed to one end of the main roller shaft near the center of the grinding disc via two main roller bearings; the main roller drive shaft is rotatably fixed inside the main roller shaft via two main roller drive shaft bearings; the two main roller bearings, the two main roller drive shaft bearings, and the secondary planetary transmission mechanism share an oil chamber;

[0048] In each of the auxiliary grinding devices, the auxiliary roller is rotatably fixed to one end of the auxiliary roller shaft near the center of the grinding disc by two auxiliary roller bearings; the auxiliary roller drive shaft is rotatably fixed inside the auxiliary roller shaft by two auxiliary roller drive shaft bearings; the two auxiliary roller bearings, the two auxiliary roller drive shaft bearings and the auxiliary roller planetary gear mechanism share an oil chamber.

[0049] Optionally, the main roller, the auxiliary roller, and the grinding disc support share a single thin oil lubrication station for providing lubricating oil to the friction points; the thin oil lubrication station has the function of centralized high-pressure and low-pressure lubrication.

[0050] Optionally, the projected pressure of the main roller on the grinding disc is 1400–1600 kN / m. 2 The projected pressure of the auxiliary roller on the grinding disc is 300–600 kN / m. 2 .

[0051] The present invention has at least the following beneficial effects:

[0052] This invention provides a vertical roller mill with both the main and auxiliary rollers being actively rotating components, along with its design method. The main and auxiliary rollers are driven by different drive devices to rotate actively. The friction of the rotating main roller on the material drives the grinding disc to actively bite into the material. Furthermore, the drive device for the main roller in this vertical roller mill employs a two-stage planetary transmission structure, improving transmission efficiency while ensuring greater torque and a more compact structure. Additionally, the structural parameters of the vertical roller mill are designed to meet actual production needs, including production time, material characteristics, and finished product characteristics. This allows for the installation of more grinding rollers on a single grinding disc, further enhancing the mill's capacity. Moreover, the design of the vertical roller mill comprehensively considers multiple parameters, including material characteristics, to achieve optimal grinding efficiency and reduce energy consumption and costs. Attached Figure Description

[0053] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0054] Figure 1 This is a front view of a vertical roller mill in which both the main roller and the auxiliary roller are actively rotating components, according to an embodiment of the present invention.

[0055] Figure 2 This is a schematic diagram of the process structure of a vertical roller mill in which both the main roller and the auxiliary roller are actively rotating components, according to an embodiment of the present invention.

[0056] Figure 3 This is an isometric view of a vertical roller mill in which both the main roller and the auxiliary roller are actively rotating components, according to an embodiment of the present invention.

[0057] Figure 4 This is a diagram of the main roller of a vertical roller mill in which both the main roller and the auxiliary roller are actively rotating components, according to an embodiment of the present invention.

[0058] Figure 5 This is a detailed diagram of the secondary planetary transmission mechanism of the main roller of a vertical roller mill, where both the main roller and the auxiliary roller are actively rotating components, according to an embodiment of the present invention.

[0059] Figure 6 This is an auxiliary roller diagram of a vertical roller mill in which both the main roller and the auxiliary roller are actively rotating components, as provided in an embodiment of the present invention.

[0060] Figure label:

[0061] In the diagram: 1. Main roller motor; 2. Coupling; 3. Main roller shaft; 4. Main roller drive shaft; 5. Main roller; 5a. Main roller sleeve; 6. Grinding shell; 7. Main roller hub; 8. Second-stage planetary transmission mechanism; 801. Second planetary carrier; 802. Second internal gear ring; 803. Second planetary gear; 804. Second planetary gear pin; 805. Horn sleeve; 806. First internal gear ring; 807. First planetary gear; 808. First planetary gear pin; 809. Second sun gear; 810. First sun gear; 811. First planetary carrier; 812. Output flange; 813. Output sleeve; 81 4. Hinged bolt; 815. Countersunk screw; 816. Main roller drive shaft bearing 1; 817. Shaft end support; 818. Cylindrical pin; 9. Auxiliary roller; 10. Auxiliary roller hydraulic cylinder; 11. Auxiliary roller shaft; 12. Auxiliary roller drive shaft; 13. Auxiliary roller motor; 14. Auxiliary roller planetary gear mechanism; 15. Connecting bridge; 16. Grinding disc self-aligning bearing; 17. Grinding disc thrust bearing; 18. Grinding disc support; 19. Grinding disc; 20. Liner; 21. Material retaining ring; 22. Bracket; 23. Main roller hydraulic cylinder; 24. Main roller drive shaft bearing 2; 25. Main roller bearing 1; 26. Main roller bearing 2. Detailed Implementation

[0062] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0063] This invention provides a design method for a vertical roller mill in which both the main roller 5 and the auxiliary roller 9 are actively rotating components. The vertical roller mill includes multiple main rollers 5 and multiple auxiliary rollers 9, with each main roller 5 corresponding to one auxiliary roller 9. Both the main rollers 5 and the auxiliary rollers 9 actively rotate to grind the material on the grinding disc 19.

[0064] Determine the main parameters of the vertical roller mill:

[0065] Based on the material characteristics, the mill's designed hourly output, and the characteristics of the finished product, the total installed power P is determined with reference to the conventional mill selection design method; the mill's designed hourly output refers to the total amount of work completed by the designed mill in one hour;

[0066] Power P of each of the main rollers M The ratio of the total installed power P to the total number of grinding rollers n is 0.82 to 0.9 times; the auxiliary roller power P of each of the auxiliary rollers 9 is... SThe power of the main roller 5 is 0.1 to 0.18 times the ratio of the total installed power P to the total number of grinding rollers n. Since the main roller 5 primarily grinds the material on the grinding disc 19, while the auxiliary roller 9 primarily pre-compresses and crushes the material on the grinding disc 19, the main roller 5 requires the majority of the power, while the auxiliary roller 9 requires relatively little. n1 is the number of main rollers, and n2 is the number of auxiliary rollers; the power of the main roller P... M The unit of the total installed power P is W; where n1 and n2 have the same value;

[0067] The grinding disc rotation speed n T The characteristic coefficient K of the material is determined, and the calculation formula is as follows:

[0068] n T =k / D T 0.5 (1)

[0069] In formula (1), the value of K ranges from 52 to 58; the grinding disc rotation speed n T The unit is m / s;

[0070] The rotational speed n of the main roller M According to the diameter D of the grinding disc T Main roller width B M Main roller diameter D M and grinding disc rotation speed n T Confirmed, the calculation formula is as follows:

[0071] n M =(D T - B M ) / D M n T (2)

[0072] In formula (2), the rotational speed n of the main roller is... M and the grinding disc rotation speed n T The unit is m / s, and the diameter D of the grinding disc is... T The width B of the main roller M Main roller diameter D M The unit is m;

[0073] The rotational speed n of the auxiliary roller S According to the diameter D of the grinding disc T Auxiliary roller width B S Auxiliary roller diameter D S and grinding disc rotation speed n T Confirmed, the calculation formula is as follows:

[0074] n S =(D T - B S ) / D S nT (3)

[0075] In formula (3), the rotational speed n of the auxiliary roller is... S The unit is m / s, and the width B of the auxiliary roller is... S Auxiliary roller diameter D S The unit is m;

[0076] In formulas (2) and (3), n M Value is 40-50 rpm, n S The rotational speed is typically between 50 and 70 rpm. Different grinding disc diameters and rotational speeds affect the distribution and movement of material on the grinding disc 19, while the width and diameter of the main roller 5 and auxiliary roller 9 affect their contact area with the material and the grinding force. Therefore, precisely adjusting the rotational speeds of the main roller 5 and auxiliary roller 9 according to these parameters ensures that the material is uniformly and thoroughly ground between the grinding disc 19, the main roller 5, and the auxiliary roller 9, thereby improving product quality and particle size uniformity. A higher rotational speed of the grinding disc 19 results in greater centrifugal force, increasing the likelihood of material being thrown off the grinding disc 19. Therefore, it is necessary to pre-set a reasonably expected rotational speed for the grinding disc 19. Based on this preset rotational speed, the rotational speeds of the main roller 5 and auxiliary roller 9 are determined to achieve that speed, allowing the main roller 5 and auxiliary roller 9 to better cooperate with the grinding disc 19 to grind the material on the grinding disc 19, thus improving grinding efficiency.

[0077] The ratio of the roller disk area A of the main roller is calculated using the following formula:

[0078] A = n1D M B M / (1 / 4πD T 2 (4)

[0079] The ratio of the auxiliary roller's disc area B is calculated using the following formula:

[0080] B = n²D S B S / (1 / 4πD T 2 (5)

[0081] The ratio of the roller disk area to A of the main roller is in the range of 0.22 to 0.32;

[0082] The ratio of the area of ​​the auxiliary roller to B is in the range of 0.12 to 0.24.

[0083] The ratio of the roller area ratio A to the roller area ratio B is in the range of 1.5 to 2.

[0084] The width B of the main roller M With the diameter D of the main roller M The ratio ranges from 0.22 to 0.34;

[0085] The width B of the auxiliary roller S With the auxiliary roller diameter D S The ratio ranges from 0.32 to 0.44;

[0086] The gap S between the main roller and the grinding disc liner M S M The value range is 30-60mm, and the gap between the auxiliary roller and the grinding disc liner is the same as the gap S between the main roller and the grinding disc liner. M 1.5 to 2 times;

[0087] The area of ​​the pre-compression crushing zone of the auxiliary roller is smaller than the area of ​​the grinding zone of the main roller, and the outer diameter of the grinding zone is larger than the outer diameter of the pre-compression crushing zone.

[0088] The distance C between the main roller 5 and the retaining ring M The distance C between the auxiliary roller 9 and the retaining ring S The distance between the main roller and the retaining ring is C. M The diameter of the grinding disc is 2 to 3 times that of the main roller 5; the height of the retaining ring is H1, which is 0.05 to 0.15 times the diameter of the grinding disc; the liner plate near the retaining ring has a groove with a groove depth H2 and a groove width L1, where the groove depth H2 is 0.1 to 0.2 times the height of the retaining ring and the groove width L1 is 2 times the groove depth H2; the distance C between the main roller 5 and the retaining ring is... M The distance C between the auxiliary roller 9 and the retaining ring S The unit for the height H1 of the retaining ring, the depth H2 of the groove, and the width L1 of the groove is mm.

[0089] Specifically, the grinding area of ​​the main roller 5 on the grinding disc 19 is larger than the pre-pressing area of ​​the auxiliary roller 9 on the grinding disc 19, and the outer diameter of the grinding area is larger than the outer diameter of the pre-pressing area. When the auxiliary roller 9 is pre-pressing, a portion of the material bypasses to both sides of the auxiliary roller 9. The material bypassing to both sides of the auxiliary roller 9 can be further bitten into and ground by the main roller, thus preventing the bypassed material from falling directly from the grinding disc 19 during the pre-pressing crushing.

[0090] The distance between the main roller 5 and the retaining ring 21 is C. M The distance C between the auxiliary roller 9 and the retaining ring 21 S The distance between the main roller 5 and the retaining ring 21 is C. M The height of the retaining ring 21 is 2 to 3 times that of the grinding disc 19; the height H1 of the retaining ring 21 is 0.05 to 0.15 times that of the grinding disc 19.

[0091] An annular liner 20 is provided in the grinding area of ​​the grinding disc 19. The portion of the liner 20 near the retaining ring 21 has a groove with a depth H2 and a width L1. The groove depth H2 is 0.1 to 0.2 times the height H1 of the retaining ring 21, and the groove width L1 is twice the groove depth H2. The presence of the groove improves the flow of material on the grinding disc 19, making the material more evenly distributed and reducing local pressure and friction. When the main roller sleeve 5a passes through the grooved area, the contact area between the main roller sleeve 5a and the material decreases due to the uniform distribution and flow of the material, reducing friction and wear. Furthermore, the groove helps to disperse the pressure on the material, reducing the stress on the main roller sleeve 5a in this area and minimizing wear.

[0092] The present invention also provides a vertical roller mill in which both the main roller and the auxiliary roller are active rotating components. The vertical roller mill includes a plurality of main grinding devices and a plurality of auxiliary grinding devices of the same number, as well as a grinding disc 19.

[0093] The main grinding device includes a main roller 5, a main drive device, a main pressurizing assembly, and a main rocker arm assembly; each main roller 5 is correspondingly provided with a main drive device, a main pressurizing assembly, and a main rocker arm assembly. The main drive device includes a main roller motor 1, a main roller coupling 2, a main roller drive shaft 4, and a secondary planetary transmission mechanism 8 connected in sequence; the main rocker arm assembly and the main pressurizing assembly are located below the corresponding main roller 5, and the main rocker arm assembly is located between the main pressurizing assembly and the corresponding main roller 5.

[0094] The auxiliary grinding device includes an auxiliary roller 9, an auxiliary drive device, an auxiliary pressurizing assembly, and an auxiliary rocker arm assembly; the main roller 5 and the auxiliary roller 9 are located inside the grinding shell 6 and are staggered circumferentially distributed on the grinding disc 19; the main roller 5 and the auxiliary roller 9 respectively form a grinding zone and a pre-compression crushing zone on the grinding disc 19, and the gap between the auxiliary roller 9 and the liner 20 on the grinding disc 19 is greater than the gap between the main roller 5 and the liner 20 on the grinding disc 19; the rotation of the main roller 5 and the auxiliary roller 9 generates frictional force on the material on the grinding disc 19, and the frictional force is transmitted to the grinding disc 19 through the material, causing the grinding disc 19 to rotate passively;

[0095] Each auxiliary roller 9 is provided with an auxiliary drive device, an auxiliary pressurizing component, and an auxiliary rocker arm component. The auxiliary drive device includes an auxiliary roller motor 13, an auxiliary roller transmission shaft 12, and an auxiliary roller planetary gear mechanism 14 connected in sequence. The auxiliary rocker arm component and the auxiliary pressurizing component are located above the corresponding auxiliary roller 9, and the auxiliary pressurizing component is fixedly connected to the outer side of the grinding shell 6.

[0096] Specifically, the vertical roller mill includes an auxiliary grinding device for pre-compressing and crushing the material on the grinding disc 19, and a main grinding device for further grinding the pre-compressed material. An auxiliary roller 9 is arranged between every two main rollers 5, and the rotation direction of the auxiliary roller 9 is the same as that of the main rollers 5. In this invention, there are multiple main rollers 5 and auxiliary rollers 9, and the number of main rollers 5 is the same as the number of auxiliary rollers 9. Depending on actual production needs, there can be 2, 3, or 4 rollers. Both the main rollers 5 and auxiliary rollers 9 are housed within the grinding shell 6.

[0097] The main roller 5 is driven to rotate actively by a main drive device. The main roller motor 1 outputs power, which is transmitted to the main roller drive shaft 4 via the main roller coupling 2. From there, the power is transmitted to the secondary planetary transmission mechanism 8. The secondary planetary transmission mechanism 8 is connected to the main roller 5 and converts most of the rotational speed transmitted from the main roller drive shaft 4 into torque, which is then transmitted to the main roller 5, causing it to rotate. The secondary planetary transmission mechanism 8 is located inside the main roller 5 at one end near the center of the grinding disc 19. The main pressurizing device is the main hydraulic cylinder 23. The extension and retraction of the main hydraulic cylinder 23, through a lever principle, drives the main roller 5 to rotate around the rocker arm pin axis. A first sun gear 810 is coaxially mounted at the end of the main roller drive shaft 4 with anti-torsional force. The first planetary carrier 811, the first internal gear ring 806, the first sun gear 810, and the main roller drive shaft 4 are all coaxially mounted. Several first planetary gears 807 are respectively mounted inside the first planetary carrier 811 via corresponding first planetary gear pins 808. The first internal gear ring 806 is disposed on the outer side of the first planetary carrier 811, and each first planet gear 807 meshes with the first internal gear ring 806 and the first sun gear 810 respectively. The output sleeve 813 is connected to the output flange 812, which is fixedly connected to the first planetary carrier 811, and power is transmitted to the output sleeve 813 through the output flange 812. In this application, there are three first planet gears 807.

[0098] The second sun gear 809 includes a first-stage step with a larger outer diameter and a second-stage step with a smaller outer diameter. Several second planet gears 803 are fixed within the second planet carrier 801 via corresponding second planet gear pins 804. A second internal gear ring 802 is disposed on the outer side of the second planet carrier 801, and each second planet gear 803 meshes with the second internal gear ring 802 and the first-stage step of the second sun gear 809. The second internal gear ring 802 is fixedly connected to the output sleeve 813 via a hinge bolt 814, transmitting power to the second internal gear ring 802. In this application, the number of second planet gears 803 is three or four.

[0099] The horn sleeve 805 in the two-stage planetary transmission mechanism 8 includes a large-diameter end and a small-diameter end. The first end of the horn sleeve 805 is the small-diameter end, and its inner surface is provided with internal teeth that mesh with the second-stage step of the second sun gear. The second end of the horn sleeve 805 is the large-diameter end, which has a stop that mates with the outer edge of the first internal gear ring 806 and is fixedly connected to the first internal gear ring 806 by bolts. The power portion of the first internal gear ring 806 can be output to the second sun gear 809 through the horn sleeve 805. The inner side of the end of the second planetary carrier 801 is provided with an internal spline. Transmitting power through the two-stage planetary transmission mechanism is beneficial for improving transmission efficiency, ensuring a large driving torque, and features a compact structure, convenient assembly and disassembly, high reliability, and ease of promotion.

[0100] The main roller drive shaft 4 is rotatably fixed inside the main roller shaft 3 via a main roller drive shaft bearing 816 and a shaft end support 817. The shaft end support 817 is fixed to the end of the main roller shaft 3 near the grinding roller by countersunk screws 815 and cylindrical pins 818. The main roller drive shaft bearing 816 is located inside the shaft end support 817. The outer surface of the shaft end support 817 is provided with splines. The splines on the outer surface of the shaft end support 817 mesh with the splines on the inner side of the end of the second planetary carrier 801. The main roller drive shaft bearing 816 is a large clearance self-aligning roller bearing, which has excellent self-aligning capability and can withstand heavier loads. The secondary planetary transmission mechanism 8 is located on one edge of the main roller hub 7 and inside the grinding housing 6. The first planetary carrier 811 acts as the first power output component, outputting power to the main roller hub 7, and the first internal gear ring 806 acts as the second power output component, outputting power to the second sun gear 809. The second internal gear ring 802 is fixedly connected to the main roller hub 7 as a power output component. Power is simultaneously transmitted to the main roller hub 7 via a secondary planetary transmission mechanism 8. Using the secondary planetary transmission mechanism 8 to drive the main roller 5 provides a large reduction ratio and output torque, reducing the size of the upstream transmission system and the main roller drive shaft 4, thus helping to lower equipment costs. Furthermore, the secondary planetary transmission mechanism 8 does not bear the grinding force of the main roller 5, improving the reliability of the equipment.

[0101] The auxiliary roller 9 is driven to rotate actively by an auxiliary drive device. The auxiliary roller motor 13 outputs power, which is transmitted to the auxiliary roller drive shaft 12, and then to the auxiliary roller planetary gear mechanism 14. The auxiliary roller planetary gear mechanism 14 is connected to the auxiliary roller 9 and converts a portion of the rotational speed transmitted by the auxiliary roller drive shaft 12 into torque, which is then transmitted to the auxiliary roller 9 to cause it to rotate. The auxiliary roller planetary gear mechanism 14 is located inside the auxiliary roller 9 at one end near the center of the grinding disc 19.

[0102] A retaining ring 21 is provided on the outer diameter of the grinding disc 19 to prevent material from overflowing the grinding disc 19 during the grinding process; a liner 20 is provided on the grinding disc 19 to directly contact the material during grinding, and a groove is provided on the edge of the liner 20 near the inner wall of the retaining ring 21.

[0103] In this invention, the coupling 2 of the main roller is a universal coupling. The universal coupling can enable the connected transmission shaft and motor to rotate continuously and reliably transmit torque and motion even when the two shafts are not on the same axis and there is an angle between the axes.

[0104] In one possible implementation, the bottom of the grinding disc 19 is rotatably fixed to the grinding disc support frame 18 by a grinding disc self-aligning bearing 16 and a grinding disc thrust bearing 17.

[0105] Specifically, the self-aligning bearing 16 allows the central axis of the grinding disc 19 to deviate angularly within a certain range, which helps to automatically correct for misalignment caused by minor deviations during installation or operation. Therefore, it reduces vibration and noise caused by axis misalignment, enhancing the stability of the entire system. Furthermore, due to the synergistic effect of the self-aligning bearing and the grinding disc thrust bearing 17, the grinding disc 19 experiences more uniform force during rotation, reducing component wear caused by uneven force distribution. This not only extends the service life of the equipment but also reduces the failure rate due to component damage.

[0106] In one possible implementation, both the main roller motor 1 and the auxiliary roller motor 13 are adjustable speed motors, which can adjust the rotational speed of the main roller 5 and the auxiliary roller 9 respectively.

[0107] Specifically, the adjustable speed motor is a variable frequency motor or a permanent magnet motor, which can adjust the speed and output power for different materials.

[0108] In one possible implementation, the main grinding device further includes a main roller shaft 3 and a bracket 22 for supporting the main rocker arm assembly;

[0109] The main roller drive shaft 4 is rotatably fixed inside the main roller shaft 3;

[0110] One end of the main rocker arm assembly is fixed to the outer surface of the main roller shaft 3, and the other end of the main rocker arm assembly is fixed to the bracket 22. Specifically, the other end of the main rocker arm assembly is rotatably fixed to the bracket 22 via a rocker arm pin.

[0111] The two adjacent supports 22 are connected by a connecting bridge 15.

[0112] In one possible implementation, the vertical roller mill further includes an auxiliary roller shaft 11;

[0113] The auxiliary roller drive shaft 12 is rotatably fixed inside the auxiliary roller shaft 11;

[0114] The auxiliary rocker arm assembly is fixed in the middle to the outer surface of the auxiliary roller shaft 11; the first end of the auxiliary rocker arm assembly is hinged to the auxiliary pressurizing assembly, and the second end of the rocker arm assembly is hinged to the rocker arm support on the connecting bridge 15.

[0115] Specifically, the auxiliary roller pressurizing assembly is an auxiliary roller hydraulic cylinder 10, one end of which is fixed to the outside of the grinding shell 6, and the other end is hinged to the first end of the rocker arm via a pin. The second end of the rocker arm assembly is hinged to the rocker arm support on the connecting bridge 15. Under the action of the auxiliary roller hydraulic cylinder 10, the auxiliary roller 9 uses the lever principle to pre-compress and crush the material on the grinding disc 19, and prolongs the residence time of the material in the grinding zone, so that the material can be fully ground under the action of the main roller. When the material changes and the main roller sleeve 5a wears at different stages, by reasonably adjusting the loading force and speed of the auxiliary roller 9, good material spreading and crushing performance can be obtained, which helps to improve the stability of the material bed.

[0116] In one possible implementation, in each of the main grinding devices, the main roller 5 is rotatably fixed to one end of the main roller shaft near the center of the grinding disc via two main roller bearings; the main roller drive shaft 4 is rotatably fixed inside the main roller shaft 3 via two main roller drive shaft bearings; the two main roller bearings, the two main roller drive shaft bearings, and the secondary planetary transmission mechanism 8 share an oil chamber. In this application, the two main roller drive shaft bearings are main roller drive shaft bearing one 816 and main roller drive shaft bearing two 24, and the two main roller bearings are main roller bearing one 25 and main roller bearing two 26.

[0117] In each of the auxiliary grinding devices, the auxiliary roller 9 is rotatably fixed to one end of the auxiliary roller shaft 11 near the center of the grinding disc by two auxiliary roller bearings; the auxiliary roller drive shaft 12 is rotatably fixed inside the auxiliary roller shaft 11 by two auxiliary roller drive shaft bearings; the two auxiliary roller bearings, the two auxiliary roller drive shaft bearings and the auxiliary roller planetary gear mechanism 14 share an oil chamber.

[0118] In one possible implementation, the main roller 5, the auxiliary roller 9, and the grinding disc support 18 share a single thin oil lubrication station for supplying lubricating oil to the friction points. The thin oil lubrication station has both high-pressure and low-pressure centralized lubrication functions. Specifically, the grinding disc thrust bearing 17 is lubricated under high pressure, while the other bearings are lubricated under low pressure.

[0119] In this application, a centralized thin oil lubrication station is used to replace the original three lubrication stations, which facilitates centralized lubrication control, reduces the total amount of lubricating oil used, avoids waste, and saves costs.

[0120] In one possible implementation, the projected pressure of the main roller on the grinding disc is 1400–1600 kN / m. 2 The projected pressure of the auxiliary roller on the grinding disc is 300–600 kN / m.2 .

[0121] In this application, the projected pressure of each main roller 5 on the grinding disc 19 is 1400–1600 kN / m. 2 The projected pressure of the main roll of a traditional vertical roller mill is 1000–1200 kN / m. 2 The projected pressure of each auxiliary roller 9 on the grinding disc 19 is 300–600 kN / m. 2 The projected pressure of the auxiliary roller in a traditional vertical roller mill is 100–200 kN / m. 2 .

[0122] Example

[0123] The actively rotating main roller 5, under the action of the main roller hydraulic cylinder 23, applies a certain roller pressure to the material on the grinding disc 19 using the lever principle. The torque of the main roller 5 generates a certain frictional force on the material on the grinding disc 19, which is transmitted to the grinding disc 19 through the material, thereby driving the grinding disc 19 to rotate. Under the action of centrifugal force, the material moves outward. The material that crosses the baffle ring 21 is carried up by the high-speed airflow at the air ring. Fine particles enter the classifier for sorting, while coarse particles fall into the grinding disc 19 and are ground again. The actively rotating auxiliary roller 9, under the action of the auxiliary roller hydraulic cylinder 10, uses the lever principle to pre-compress and crush the material on the grinding disc 19 and prolong the residence time of the material in the grinding zone. This optimizes the movement of the material on the grinding disc 19, allowing the material to be fully ground under the action of the main roller 5.

[0124] By adjusting the loading force of the auxiliary rollers according to changes in material properties and different stages of roller sleeve wear, excellent material spreading and crushing performance can be achieved, which helps to improve the stability of the material bed. The vertical roller mill designed using the method provided in this invention, where both the main roller and auxiliary rollers are actively rotating components, has a strong main roller feeding capacity, stable material layer, smooth operation, and low overall power consumption per unit. Compared with conventional disc-driven vertical mills, the grinding pressure of the grinding rollers is greater, resulting in greater shearing force on each layer of material and higher grinding efficiency.

[0125] It should be noted that the center lines of the main roller shaft and the auxiliary roller shaft are not limited in this invention. The center lines of the main roller shaft and the auxiliary roller shaft shown in the figure are both horizontally arranged. In other embodiments, the center lines of the main roller shaft and the auxiliary roller shaft are set at a certain angle, such as 15°, which is applicable to known technologies in the field of vertical mill grinding, such as flat disc column rollers, flat disc cone rollers, and bowl-shaped tire rollers.

[0126] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0127] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A design method for a vertical roller mill in which both the main roller and the auxiliary roller are actively rotating components, characterized in that, The vertical roller mill includes multiple main rollers and multiple auxiliary rollers, with each main roller corresponding to one auxiliary roller; both the main rollers and auxiliary rollers rotate actively to grind the material on the grinding disc. Determine the main parameters of the vertical roller mill: The total installed power is determined based on material characteristics, mill design hourly output, and finished product characteristic parameters, referring to conventional mill selection design methods. P The designed hourly output of the mill is the total amount of work that the mill is designed to complete in one hour. Main roller power of each of the main rollers P M The total installed power P Total number of grinding rollers n The ratio is 0.82 to 0.9 times; the auxiliary roller power of each of the auxiliary rollers. P S The total installed power P With the total number of the grinding rollers n The ratio is 0.1 to 0.18 times; n 1 is the number of main rollers. n 2 represents the number of auxiliary rollers. n 1= n 2; The power of the main roller P M and the total installed power P The unit is W; The grinding speed of the grinding disc n T The characteristic coefficient K of the material is determined, and the calculation formula is as follows: n T =K / D T 0.5 (1) In formula (1), the value of K ranges from 52 to 58; D T The diameter of the grinding disc is in meters (m); the rotational speed of the grinding disc is... n T The unit is m / s; The rotational speed of the main roller n M According to the diameter of the grinding disc D T 、 Main roller width B M , main roller diameter D M and grinding disc speed n T Confirmed, the calculation formula is as follows: n M =( D T - B M ) / D M n T (2) In formula (2), the rotational speed of the main roller is... n M and the rotational speed of the grinding disc n T The unit is m / s, and the diameter of the grinding disc is... D T The width of the main roller B M , main roller diameter D M The unit is m; The rotational speed of the auxiliary roller n S According to the diameter D of the grinding disc T Auxiliary roller width B S auxiliary roller diameter D S and grinding disc speed n T Confirmed, the calculation formula is as follows: n S =( D T - B S ) / D S n T (3) In formula (3), the rotational speed of the auxiliary roller is... n S The unit is m / s, and the width of the auxiliary roller is... B S auxiliary roller diameter D S The unit is m; In formulas (2) and (3), n M Take a value of 40~50 rpm. n S Value: 50~70 rpm; The ratio of the roller disk area A of the main roller is calculated using the following formula: A=n1 D M B M / (1 / 4π D T 2 (4) The ratio of the auxiliary roller's disc area B is calculated using the following formula: B=n2 D S B S / (1 / 4π D T 2 )(5) The ratio of the roller disk area to A of the main roller is in the range of 0.22 to 0.32; The ratio of the area of ​​the auxiliary roller to B is in the range of 0.12 to 0.

24. The ratio of the roller area ratio A to the roller area ratio B is in the range of 1.5 to 2. The width of the main roller B M With the diameter of the main roller D M The ratio ranges from 0.22 to 0.34; The width of the auxiliary roller B S With the diameter of the auxiliary roller D S The ratio ranges from 0.32 to 0.44; The gap between the main roller and the grinding disc liner S M , S M The value range is 30~60mm, and the gap between the auxiliary roller and the grinding disc liner is the same as the gap between the main roller and the grinding disc liner. S M 1.5 to 2 times; The area of ​​the pre-compression crushing zone of the auxiliary roller is smaller than the area of ​​the grinding zone of the main roller, and the outer diameter of the grinding zone is larger than the outer diameter of the pre-compression crushing zone. The distance between the main roller and the retaining ring C M The distance between the auxiliary roller and the retaining ring C S The distance between the main roller and the retaining ring is C M 2 to 3 times; height of the retaining ring H 1. Height of the retaining ring H 1 is 0.05 to 0.15 times the diameter of the grinding disc; the portion of the liner near the retaining ring has a groove, the groove depth is... H 2. Groove width L 1. Depth of the groove H 2 is the height of the retaining ring. H The groove width is 0.1 to 0.2 times that of 1. L 1 represents the depth of the groove. H 2 times; the distance between the main roller and the retaining ring. C M The distance between the auxiliary roller and the retaining ring C S The height of the retaining ring H 1. Depth of the groove H 2. Groove width L The unit of 1 is mm.

2. A vertical roller mill in which both the main roller and the auxiliary roller are actively rotating components, characterized in that, The vertical roller mill, manufactured using the design method described in claim 1, comprises a plurality of main grinding devices and a plurality of auxiliary grinding devices of equal number, as well as a grinding disc; The main grinding device includes a main roller, a main drive unit, a main pressurizing assembly, and a main rocker arm assembly; each main roller is correspondingly provided with a main drive unit, a main pressurizing assembly, and a main rocker arm assembly. The main drive unit includes a main roller motor, a main roller coupling, a main roller drive shaft, and a secondary planetary transmission mechanism connected in sequence; the main rocker arm assembly and the main pressurizing assembly are located below the corresponding main roller, and the main rocker arm assembly is located between the main pressurizing assembly and the corresponding main roller. The auxiliary grinding device includes an auxiliary roller, an auxiliary drive device, an auxiliary pressurizing assembly, and an auxiliary rocker arm assembly; the main roller and the auxiliary roller are located inside the grinding shell and are staggered circumferentially distributed on the grinding disc; the main roller and the auxiliary roller respectively form a grinding zone and a pre-compression crushing zone on the grinding disc, and the gap between the auxiliary roller and the liner plate on the grinding disc is greater than the gap between the main roller and the liner plate on the grinding disc; the rotation of the main roller and the auxiliary roller generates frictional force on the material on the grinding disc, and the frictional force is transmitted to the grinding disc through the material, causing the grinding disc to rotate passively; Each auxiliary roller is provided with an auxiliary drive device, an auxiliary pressurizing component, and an auxiliary rocker arm component. The auxiliary drive device includes an auxiliary roller motor, an auxiliary roller drive shaft, and an auxiliary roller planetary gear mechanism connected in sequence. The auxiliary rocker arm component and the auxiliary pressurizing component are located above the corresponding auxiliary roller, and the auxiliary pressurizing component is fixedly connected to the outer side of the grinding shell.

3. The vertical roller mill according to claim 2, wherein both the main roller and the auxiliary roller are actively rotating components, is characterized in that, The bottom of the grinding disc is rotatably fixed to the grinding disc support frame by a grinding disc self-aligning bearing and a grinding disc thrust bearing.

4. The vertical roller mill according to claim 2, wherein both the main roller and the auxiliary roller are actively rotating components, is characterized in that, Both the main roller motor and the auxiliary roller motor are adjustable speed motors, which can adjust the speed of the main roller and the auxiliary roller respectively.

5. The vertical roller mill according to claim 2, wherein both the main roller and the auxiliary roller are actively rotating components, is characterized in that, The main grinding device also includes a main roller shaft and a bracket for supporting the main rocker arm assembly; The main roller drive shaft is rotatably fixed inside the main roller shaft; One end of the main rocker arm assembly is fixed to the outer surface of the main roller shaft, and the other end of the main rocker arm assembly is fixed to the bracket; The two adjacent supports are connected by a connecting bridge.

6. The vertical roller mill according to claim 5, wherein both the main roller and the auxiliary roller are actively rotating components, is characterized in that, The vertical roller mill also includes an auxiliary roller shaft; The auxiliary roller drive shaft is rotatably fixed inside the auxiliary roller shaft; The auxiliary rocker arm assembly is fixed in the middle to the outer surface of the auxiliary roller shaft; the first end of the auxiliary rocker arm assembly is hinged to the auxiliary pressurizing assembly, and the second end of the rocker arm assembly is hinged to the rocker arm support on the connecting bridge.

7. The vertical roller mill according to claim 5, wherein both the main roller and the auxiliary roller are actively rotating components, is characterized in that, In each of the main grinding devices, the main roller is rotatably fixed to one end of the main roller shaft near the center of the grinding disc by two main roller bearings; the main roller drive shaft is rotatably fixed inside the main roller shaft by two main roller drive shaft bearings; the two main roller bearings, the two main roller drive shaft bearings, and the secondary planetary transmission mechanism share an oil chamber. In each of the auxiliary grinding devices, the auxiliary roller is rotatably fixed to one end of the auxiliary roller shaft near the center of the grinding disc by two auxiliary roller bearings; the auxiliary roller drive shaft is rotatably fixed inside the auxiliary roller shaft by two auxiliary roller drive shaft bearings; the two auxiliary roller bearings, the two auxiliary roller drive shaft bearings and the auxiliary roller planetary gear mechanism share an oil chamber.

8. The vertical roller mill according to claim 3, wherein both the main roller and the auxiliary roller are actively rotating components, is characterized in that, The main roller, the auxiliary roller, and the grinding disc support frame share a single thin oil lubrication station, which is used to provide lubricating oil to the friction points; the thin oil lubrication station has the function of centralized high-pressure and low-pressure lubrication.

9. The vertical roller mill according to claim 2, wherein both the main roller and the auxiliary roller are actively rotating components, is characterized in that, The projected pressure of the main roller on the grinding disc is 1400~1600 KN / m 2 The projected pressure of the auxiliary roller on the grinding disc is 300~600KN / m. 2 .

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