Device for preventing adhesion of powder to crusher chute and crusher

Abstract

To provide a chute powder attachment-preventing device for a crusher.SOLUTION: A plurality of link chains as suspension members 9 inside chutes 8 arranged on an outlet side of a crusher 10, or U-shaped link chains as being set in an endless state by connecting end portions of the link chains to each other are suspended to support members 11, and are suspended from above along inner wall faces of the chutes 8 onto which powder crushed by the crusher 10 is attached. The powder attached onto the inner wall faces of the chutes can be scraped off by transmitting vibrations during an operation of the crusher to the suspension members via for example, a crusher casing and a support member. Thus, it can be suppressed to attach the powder to the chutes, and an attachment suppression effect is hardly deteriorated even in a long-time operation.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a crusher suitable for crushing raw materials for iron and steel in iron-making processes and the like, and in particular to a powder and granular material adhesion prevention device for a crusher chute that prevents the adhesion of raw materials (powders) to the inner wall surfaces of the chute, etc., even if the raw materials are highly adhesive, and enables stable operation of the crusher, and to a crusher. [Background technology]

[0002] For example, in the iron-making process, various raw materials are crushed by a crusher to improve reactivity and homogeneity, and are used as raw materials for iron-making. Impact crushers, which accelerate the input raw materials with a rotating rotor and crush them by slamming them against a collision plate, are widely used as they have the advantages of having a relatively large size limit for the input raw materials and a large crushing ratio.

[0003] However, when the raw material used is highly adhesive, or when the moisture content of the raw material increases due to rainfall or water sprinkling to prevent dust generation, the crushed raw material (granular material) may collide with the inner wall of the chute installed at the outlet side (downstream) of the crusher, some of which may adhere to it, and as crushing continues, the adhesion may grow, eventually clogging the chute. When this happens, the crusher cannot operate continuously, the crushing capacity drops significantly, and productivity drops.

[0004] To prevent such highly adhesive raw materials from adhering to the inner walls of the chute, one possible method is to install compressed air nozzles on the wall of the chute to inject compressed air into the chute, or to use a vibrator to impact the outer surface of the chute, thereby continuously peeling off and removing the powder and granular material adhering to the inner walls of the chute. However, in order to achieve an adequate effect, several compressors, vibrators, and other equipment are required, and further space is required to install the equipment, making this economically disadvantageous.

[0005] Various methods have been proposed to prevent such sticky materials from adhering to the inner walls of the chute.

[0006] For example, Patent Document 1 describes an "apparatus for removing raw materials adhering to a conveyor chute." The "apparatus for removing adhering raw materials" described in Patent Document 1 is an apparatus for removing raw materials adhering to a chute for a conveyor that is transported by an upstream conveyor and guided to the next downstream conveyor, and is provided with a rubber sloped section within the chute through which raw materials released from the upstream conveyor fall, and further includes a deformation means for deforming a part or all of the rubber sloped section from the outside to the inside, thereby breaking up and removing raw materials adhering to the rubber sloped section.

[0007] Patent Document 2 also describes a "wall-adhering powder / granule scraping device" that scrapes off powder / granules that adhere to the wall of a flow path. The "wall-adhering powder / granule scraping device" described in Patent Document 2 is a device that scrapes off powder / granules that adhere to the wall of a chute that sends coal from a coal feeder to a mill (crusher), and includes a pair of endless chains arranged near both sides of the wall to which the powder / granules adhere, a scraper that is attached perpendicular to the pair of chains and scrapes off the powder / granules that adhere to the wall, a chain wheel that rotates and drives the chain, a chain tension adjustment device that adjusts the tension of the chain, a pinch prevention plate that prevents the powder / granules from getting pinched between the chain wheel and the chain, and an air ejection nozzle that blows off the powder / granules that are placed on the chain.

[0008] Patent Document 3 also describes a "device for preventing powder adhesion to a chute at a transfer section of a belt conveyor." In the "device for preventing powder adhesion to a chute" described in Patent Document 3, multiple link chains are suspended from above on support rods in a transfer section chute provided at the discharge end of the belt conveyor, and are densely arranged to block the falling parabolic flow path of the conveyed object. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] JP 2002-316707 A [Patent Document 2] JP 2009-112897 A [Patent Document 3] Japanese Patent Application Publication No. 10-59530 Summary of the Invention [Problem to be solved by the invention]

[0010] However, the "adhering raw material removal device" described in Patent Document 1 is intended to prevent the adhesion of powder (transported material) to a conveyor chute, and there is a risk that the adhesion prevention effect will decrease due to deterioration and wear of the rubber when used for a long period of time. In addition, the "wall-adhering powder scraping device" described in Patent Document 2 is also intended to prevent the adhesion of powder (transported material) to a conveyor chute for sending coal (transported material) from a coal feeder to a mill (crusher), and requires the installation of a chain wheel drive device that rotates the chain, and further includes increased costs for operation and maintenance management, making it expensive as a measure to prevent adhesion to the wall of the chute and economically disadvantageous. In addition, the powder adhesion prevention device described in Patent Document 3 is also intended to prevent the adhesion of powder (transported material) to a conveyor chute, and Patent Document 3 does not mention the adhesion prevention effect for powder flying at high speed, such as powder crushed by a crusher.

[0011] The present invention aims to solve such problems of the conventional technology and to provide a powder / granular material adhesion prevention device for a crusher chute, which can suppress and prevent the adhesion of crushed powder / granular material to the inner wall surface of a chute arranged on the outlet side (downstream side) of a crusher for crushing raw materials for iron and steel, etc., and a crusher using the same. [Means for solving the problem]

[0012] In order to achieve the above object, the inventors of the present invention have intensively studied effective means for preventing powder from adhering to the inner wall surface of the chute installed on the outlet side (downstream side) of the crusher. As a result, they came up with the idea of ​​using multiple link chains as hanging members, suspending the multiple link chains from above so as to run along the inner wall surface of the chute, and applying vibration to the hanging members, for example, by utilizing the vibration (swing) of the casing when the crusher is in operation. They found that this would make it possible to scrape off the adhering matter adhering to the inner wall surface of the chute.

[0013] The present invention was completed based on these findings and further investigations. [1] A device for preventing powder and granular material from adhering to a chute for a crusher arranged on the outlet side of the crusher, characterized in that a hanging member is hung from above along the inner wall surface of the chute for the crusher on the inside of the chute for the crusher. [2] The powder / granular material adhesion prevention device for a crusher chute described in [1], characterized in that the hanging member is a multiple link chain. [3] The powder / granular material adhesion prevention device for a crusher chute described in [2], characterized in that the hanging member is a U-shaped hanging member formed by connecting one end of the link chains together. [4] A powder / granular material adhesion prevention device for a crusher chute as described in any one of [1] to [3], characterized in that the hanging member is hung so as to be connectable to a casing of the crusher. [5] A powder / granular material adhesion prevention device for a crusher chute as described in [1], further comprising a vibration adding device for adding vibration to the hanging member. [6] A crusher having a chute on the outlet side, characterized in that a powder / granular material adhesion prevention device for a crusher chute described in any one of [1] to [5] is arranged on the inside of the chute as a powder / granular material adhesion prevention device. [7] The crusher described in [6], characterized in that the chute has multiple inclined surfaces having an inclination angle of 45° or more with respect to the horizontal plane. Effect of the Invention

[0014] According to the present invention, the powder particles that are crushed and accelerated by the crusher and collide with and adhere to the inner wall surface of the chute can be scraped off in an inexpensive manner, which is an industrially significant effect of preventing a decrease in crushing capacity. In addition, according to the present invention, there are also effects that the adhesion suppression effect does not decrease even during long-term operation, and that even if the hanging member breaks, the member can be easily replaced. [Brief description of the drawings]

[0015] [Figure 1] FIG. 2 is an explanatory diagram showing a schematic configuration of a crusher equipped with a chute adhesion prevention device of the present invention. [Diagram 2] FIG. 11 is an explanatory diagram illustrating a schematic diagram of another example of a powder / granular material adhesion prevention device for a crusher chute. [Diagram 3] FIG. 13 is an explanatory diagram showing a schematic example of a vibration adding device attached to a chute. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] The chute adhesion prevention device 20 of the present invention is disposed in the chute 8 disposed on the outlet side (downstream side) of the crusher 10 and has the function of suppressing and preventing the adhesion of powder and granular material to the inner wall surface of the chute 8.

[0017] The crusher to which the powder adhesion prevention device of the present invention is applied is preferably an impact crusher, which is widely used as a crusher for crushing raw materials for iron making such as iron ore, coal, limestone, etc., but needless to say, is not limited to this. An example of the device configuration when the powder adhesion prevention device 20 of the present invention is applied to a vertical crusher 10 is shown in Figure 1.

[0018] In the vertical crusher 10 shown in Fig. 1, raw material 2 is fed from outside the crusher via a raw material feeder (not shown). The fed raw material 2 is accelerated in the tangential direction by contacting multiple rotor plates 4 attached to the rotating rotor 3 rotating at high speed, and repeatedly collides with the upper collision plate 5 and the lower collision plate 6, where it is pulverized into powder 21, which is then projected at high speed in the tangential direction of the rotating rotor 3. The distance between the upper collision plate 5 and the lower collision plate 6 and the rotor plate 4 can be adjusted by operating a cylinder device 7.

[0019] The powder 21 crushed by the crusher 10 and projected at high speed collides with and adheres to the inner wall surface of the chute 8 disposed on the outlet side (downstream side) of the crusher 10. In order to prevent adhesion of material to the inner wall surface, the chute 8 preferably has multiple inclined surfaces with an inclination angle α of 45° or more relative to the horizontal plane.

[0020] The powder / granular material adhesion prevention device 20 of the present invention, which is disposed within the chute 8, has a support member 11 and a hanging member hung from the support member 11. The hanging member is preferably a plurality of link chains 9. In the present invention, the support member 11 is preferably configured so as to be connectable to the casing 1 of the crusher. By being connected to the casing 1 of the crusher, vibrations generated during operation of the crusher are transmitted to the link chain serving as the hanging member 9. The support member 11 is preferably rod-shaped so as to be connectable to the crusher casing 1, but there is no particular need to limit the shape, material, etc., of the support member 11.

[0021] In Fig. 1, the hanging member is shown installed at two locations to correspond to the forward and reverse rotation of the rotor, but it is needless to say that the present invention is not limited to this. It is sufficient that the hanging member is installed at at least one location in accordance with the rotation direction of the rotor.

[0022] The hanging member 9 is preferably a multiple link chain 9 as shown in Fig. 2. Examples of the link chain include various link chains (short links) as specified in JIS F 2106. The size of the material (link chain) used for the hanging member 9 may be appropriately selected depending on the size of the raw materials to be fed and the size of the resulting powder and granular material. For example, when crushing iron ore, a link chain with a nominal diameter of 9 to 28 mmφ is preferably used.

[0023] The hanging member 9 may be a hanging member made by sequentially connecting a plurality of materials in a manner that allows each of the materials to bend freely, in addition to the link chain. The method of connecting the materials is not particularly limited as long as each of the materials is connected in a manner that allows each of the materials to bend freely. Examples of materials for such hanging members include rod-shaped bodies, tubular bodies, and ring-shaped bodies.

[0024] In the device 20 for preventing adhesion of a chute according to the present invention, a number of link chains are suspended from a support member 11 as the hanging member 9, and suspended from above along the inner wall surface of the chute to which the powder and granular material adheres in a vibrating manner. The support member 11 is preferably attached to the crusher casing 1 so as to be capable of transmitting vibration to the hanging member 9. This allows vibrations during operation of the crusher to be transmitted to the link chain as the hanging member 9, which vibrates the link chain and scrapes off the powder and granular material adhering to the chute 8. If the natural frequency of the link chain is made to match the vibration frequency of the casing, the effect of scraping off the adhering material can be increased.

[0025] In addition to the vibration transmitted to the hanging member during operation of the crusher, a vibration adding device such as a knocker, vibrator, or air blaster may be provided to add vibration to the hanging member. The vibration from the vibration adding device may be added alone or in addition to the vibration from the crusher during operation. The vibration from the vibration adding device may be added directly to the hanging member or via a chute 8 as shown in FIG. 3, and can be selected appropriately. Examples of the vibration adding device include a vibrator, air jet, and air knocker. Furthermore, if the frequency of the added vibration is adjusted to match the resonant frequency of the link chain, which is the hanging member, the scraping effect of the attached material is increased.

[0026] Furthermore, as shown in Fig. 1, it is preferable that the hanging member 9 is an endless U-shaped hanging member made by connecting one end (free end) of a link chain together. By hanging such a hanging member 9 from a support member 11, even if the hanging member (link chain) breaks, it is easy to replace the hanging member (link chain), and furthermore, it is possible to prevent the hanging member (link chain) from being discharged from the discharge opening of the chute.

[0027] The material of the suspending member does not need to be limited to a particular one, but from the viewpoints of economy and securing a suitable weight, it is preferable to use iron or steel, and from the viewpoint of corrosion resistance, stainless steel. However, as long as a certain weight or more can be secured, there is no problem in using rubber or plastic. EXAMPLES

[0028] (Example 1 of the present invention) As shown in Fig. 1, a chute 8 consisting of four inclined surfaces was provided on the outlet side of a vertical crusher 10. The inclined surfaces were provided so as to be inclined at an angle of α = 64° with respect to the horizontal plane.

[0029] The raw material was fed into the crusher from above the crusher casing 1 and crushed. The raw material fed was iron ore with a particle size of 0.1 to 30 mm. The fed raw material 2 was accelerated in the tangential direction of the rotation by contacting the rotor plate 4, and repeatedly collided with the upper collision plate 5 and the lower collision plate 6 to become powder and granular material, which was projected at high speed in the tangential direction of the rotating rotor 3. The average particle size of the crushed powder and granular material was 500 μm. The peripheral speed of the tip of the rotating rotor 3 was 40 to 60 m / sec.

[0030] The powder adhesion prevention device 20 used had a hanging member formed by joining one end of a link chain together to form a U-shape, as shown in Fig. 1, and multiple such hanging members (6 pieces) were hung from a single rod-shaped support member 11 as shown in Fig. 1, and hung from above along the inner wall surface of the chute, with the support member 11 being connected to the casing 1 of the crusher. The link chain used was a steel link chain (short chain link) with a nominal diameter of 16 mmφ.

[0031] The raw materials were then fed into the crusher 10, and after the raw materials were crushed, the thickness of the deposits on the inner wall surface of the chute 8 was measured. During crushing, the vibrations generated during operation of the crusher were transmitted to the link chain 9 via the casing 1 and the support member 11. This caused the powder particles adhering to the inner wall surface of the chute 8 to be scraped off. As a result, after 117 tons of raw materials had passed through, the thickness of the deposits on the inner wall surface of the chute 8 was 10 mm or less.

[0032] (Comparative Example) As a comparative example, the crusher 10 shown in FIG. 1 was used to crush the raw materials without using the powder adhesion prevention device for the chute, and the thickness of the deposits adhering to the chute 8 was measured. The raw materials fed were iron ores with particle sizes of 0.1 to 30 mm, the same as in the present invention. After 74 tons of the raw materials had passed through, the thickness of the deposits adhering to the inner wall surface of the chute 8 was 250 mm (maximum). [Explanation of symbols]

[0033] 1 Crusher casing 2 Raw materials 3 Rotor 4 Rotor plate 5 Upper collision plate 6 Lower collision plate 7 Cylinder device 8. SHOTS 9 Suspension members (link chains) 10 Crusher 11 Support member 12 Vibration device 20 Chute adhesion prevention device

Claims

1. A powder / granular material adhesion prevention device for a crusher chute arranged on the outlet side of the crusher, characterized in that a hanging member is hung from above along an inner wall surface of the crusher chute inside the crusher chute, and the hanging member is hung so as to be connectable to a casing of the crusher.

2. 2. The powder adhesion prevention device for a crusher chute according to claim 1, wherein the hanging member is a multiple link chain.

3. 3. The powder adhesion prevention device for a crusher chute according to claim 2, wherein the hanging member is a U-shaped hanging member formed by connecting one ends of the link chains together.

4. A crusher having a chute on the outlet side, characterized in that a powder / granular material adhesion prevention device for a crusher chute according to any one of claims 1 to 3 is disposed inside the chute as a powder / granular material adhesion prevention device.

5. 5. The crusher according to claim 4, wherein the chute has a plurality of inclined surfaces each having an inclination angle of 45 degrees or more with respect to a horizontal plane.

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