Method for improving yield of vertical mill

Abstract

The invention relates to a method for increasing the yield of a vertical mill, and belongs to the technical field of vertical grinding machinery. According to the technical scheme, an annular protrusion (5) is arranged on the outer circumference, close to a material blocking ring (3), of a grinding roller (1), the annular protrusion (5) is matched with a gap between the grinding roller and the material blocking ring (3), materials are ground, and the area of a grinding area is increased. The vertical mill has the beneficial effects that the gap between the grinding roller and the retaining ring is reduced, the gap space between the grinding roller and the retaining ring is fully utilized to grind materials, the yield and the grinding efficiency of the vertical mill are improved, normal discharging of the vertical mill is not affected, and the technical prejudice in the field is overcome.

Description

Technical Field

[0001] The invention relates to a method for improving the output of a vertical mill, and belongs to the technical field of vertical grinding machinery. Background Art

[0002] Vertical mills are widely used in industries such as cement, electricity, metallurgy, chemical industry and non-metallic minerals. They have high production capacity and a wide range of applications. The working process includes the steps of material crushing, drying, grinding and classification. It can process block, granular and powdered raw materials to meet the production needs of different industries. For example, the metallurgical industry uses vertical mills to crush blast furnace slag. The main components of the vertical mill include grinding discs, grinding rollers and powder concentrators. The grinding disc is matched with grinding rollers. The motor drives the grinding disc to rotate through the vertical reducer. The material enters the center of the grinding disc from the material inlet and is dispersed around the grinding disc under the action of centrifugal force. The outer circumference of the grinding disc is provided with a retaining ring. The grinding roller rotates under the friction of the grinding disc, rolling and shearing the material to form a material bed (grinding area) for further crushing. The ground material reaches the gap between the grinding roller and the retaining ring. The gap is a circular discharge port. Under the suction of the exhaust fan, it enters the powder concentrator for classification. Qualified fine powder is collected as a finished product. The problem with the existing technology is that since the vertical mill needs to discharge materials through the gap between the grinding roller and the retaining ring on the circumference of the grinding disc, ordinary technicians in this field have a technical prejudice and believe that the gap space between the grinding roller and the retaining ring on the circumference of the grinding disc cannot be ground, otherwise it will affect the normal discharge of the vertical mill, so that the material is not ground by the grinding roller in the gap space, resulting in a relatively small grinding area between the grinding roller and the grinding disc, which affects the output of the vertical mill; and the grinding force of the area close to the retaining ring of the grinding roller is the largest, and the grinding efficiency is also the highest. The gap between the grinding roller and the retaining ring is not utilized, which affects the grinding efficiency. Chinese patent CN201721424138.X is named "Gap Adjustment Device for Grinding Roller and Grinding Disc in Slag Vertical Mill", which is used to adjust the gap between the grinding roller and the grinding disc to eliminate the excessive gap between the grinding surfaces of the grinding disc and the grinding roller caused by wear, but it cannot solve the problem of excessive gap between the grinding roller and the retaining ring. Summary of the invention

[0003] The purpose of the present invention is to provide a method for increasing the output of a vertical mill, reducing the gap between the grinding roller and the material retaining ring, making full use of the gap space between the grinding roller and the material retaining ring to grind the material, thereby increasing the output and grinding efficiency of the vertical mill without affecting the normal discharge of the vertical mill, overcoming the technical prejudice existing in this field, and solving the problems existing in the background technology.

[0004] The technical solution of the present invention is: A method for improving the output of a vertical mill, wherein materials enter the center of a grinding disc from a material inlet, are dispersed around the grinding disc under the action of centrifugal force, a retaining ring is provided on the outer circumference of the grinding disc, a grinding roller rotates under the action of the friction force of the grinding disc, and crushes and shears the materials to form a grinding area for further crushing, and the ground materials reach the gap between the grinding roller and the retaining ring, which is an annular discharge port, and enter a powder classifier for classification under the suction force of an exhaust fan, and qualified fine powder is collected as a finished product; the special feature of the method is that an annular protrusion is provided on the outer circumference of the grinding roller close to the retaining ring, and the annular protrusion matches the gap between the grinding roller and the retaining ring, grinds the materials, and increases the area of ​​the grinding area.

[0005] The cross section of the annular protrusion is an arc-shaped protrusion.

[0006] The annular protrusion is repaired by surfacing welding after being worn.

[0007] The annular protrusion may be an integral structure with the grinding roller, or may be formed into one by welding.

[0008] By adding annular protrusions, the grinding area of ​​the vertical mill roller is extended. Without reducing the service life of the vertical mill roller, the grinding area is enlarged. During production and use, the operating area of ​​the vertical mill roller for milling is increased, thereby increasing the powder output of the vertical mill.

[0009] The beneficial effects of the present invention are as follows: the gap between the grinding roller and the material retaining ring is reduced, the gap space between the grinding roller and the material retaining ring is fully utilized to grind the material, the output and grinding efficiency of the vertical mill are improved, and the normal discharge of the vertical mill is not affected, thus overcoming the technical prejudice existing in the field. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a schematic diagram of the existing technical structure of the present invention; Figure 2 A cross-sectional view of a grinding roller according to an embodiment of the present invention; Figure 3 It is an overall structural diagram of an embodiment of the present invention; In the figure: grinding roller 1, grinding disc 2, material retaining ring 3, material inlet 4, annular protrusion 5, grinding area 6. DETAILED DESCRIPTION

[0011] The present invention will be further described below by way of examples in conjunction with the accompanying drawings.

[0012] A method for improving the output of a vertical mill, wherein materials enter the center of a grinding disc 2 from a material inlet, are dispersed around the grinding disc 2 under the action of centrifugal force, a retaining ring 3 is provided on the outer circumference of the grinding disc 2, a grinding roller 1 rotates under the friction of the grinding disc 2, and crushes and shears the materials to form a grinding area 6 for further crushing, and the ground materials reach the gap between the grinding roller and the retaining ring 3, which is an annular discharge port 4, and enter a powder classifier for classification under the suction force of an exhaust fan, and qualified fine powder is collected as a finished product; the special feature of the method is that an annular protrusion 5 is provided on the outer circumference of the grinding roller 1 close to the retaining ring 3, and the annular protrusion 5 matches the gap between the grinding roller and the retaining ring 3, grinds the materials, and increases the area of ​​the grinding area.

[0013] The cross section of the annular protrusion 5 is an arc-shaped protrusion.

[0014] The annular protrusion 5 is repaired by surfacing welding after being worn.

[0015] The annular protrusion 5 can be an integral structure with the grinding roller, or can be integrated by welding.

[0016] By adding the annular protrusion 5, the grinding area of ​​the vertical mill roller is extended. Without wasting the service life of the vertical mill roller, the grinding area is enlarged. During production and use, the working area of ​​the vertical mill roller for milling is increased, and the powder output of the vertical mill is increased.

[0017] In the embodiment, the cross section of the annular protrusion 5 is an arc-shaped protrusion, and the arc radius is 70 mm. After the vertical mill is running, the following two changes are obtained through actual measurement: 1. The unit-hour capacity increased from 150 tons / hour to 166 tons / hour; 2. The mill current changes from 220-280AH to 270-300AH, which is relatively stable; 3. The width of the grinding area is increased from 700mm to 750mm.

[0018] The output of the mill is effectively increased by adding the annular protrusion 5. Since the material is sucked by negative pressure, the normal discharge of the vertical mill is not affected. The present invention overcomes the technical prejudice in the art.

Claims

1. A method for improving the output of a vertical mill, wherein the material enters the center of a grinding disc (2) from a material inlet, is dispersed around the grinding disc (2) by the action of centrifugal force, a retaining ring (3) is provided on the outer circumference of the grinding disc (2), the grinding roller (1) rotates under the friction of the grinding disc (2), and the material is crushed and sheared to form a grinding area (6) for further crushing, and the ground material reaches the gap between the grinding roller and the retaining ring (3), which is a ring-shaped discharge port (4), and enters a powder classifier for classification under the suction force of an exhaust fan, and qualified fine powder is collected as a finished product; the method is characterized in that: An annular protrusion (5) is provided on the outer circumference of the grinding roller (1) near the retaining ring (3); the annular protrusion (5) matches the gap between the grinding roller and the retaining ring (3) to grind the material and increase the grinding area.

2. A method for increasing the output of a vertical mill according to claim 1, characterized in that: The cross section of the annular protrusion (5) is an arc-shaped protrusion.

3. A method for increasing the output of a vertical mill according to claim 1 or 2, characterized in that: The annular protrusion (5) is repaired by surfacing welding after being worn.

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