JP6440402B2 - Vertical roller mill - Google Patents

Description

  The present invention relates to a vertical roller mill that pulverizes an object to be crushed between a pulverizing roller and a rotary table.

  2. Description of the Related Art Conventionally, a vertical roller mill that pulverizes a material to be crushed (raw material) between a pulverizing roller and a rotary table has been used for manufacturing concrete aggregates. In a vertical roller mill, a raw material made of slag, clinker or the like is supplied via a raw material charging chute onto a rotary table that is driven to rotate around a vertical rotation axis.

  In general, a raw material charging chute for charging raw material onto a rotary table includes a center chute-type raw material charging chute that extends vertically along the vertical rotation axis of the rotary table and a vertical rotation axis of the rotary table. There is a side chute type material input chute that extends at an angle.

  The raw material supplied onto the rotary table via the raw material charging chute moves to the outside in the radial direction by centrifugal force accompanying the rotation of the rotary table, and is pulverized by being pressed toward the working surface (grinding surface) of the rotary table. It is crushed by being caught between the roller and the rotary table.

  The raw material caught between the pulverizing roller and the rotary table and pulverized is discharged radially outward from the rotary table by the centrifugal force of the rotary table, and the raw material (powder) pulverized to a desired particle size (particle size). Body) is classified and recovered. In this classification step, the wind pressure of the gas (hot air) that is introduced into the inside of the mill casing through the hot air duct and blows up, and a separator disposed above the inside of the mill casing are used.

  By the way, among raw materials that are pulverized by a vertical roller mill, wet raw materials with a high water content such as slag have high adhesion to surrounding structures and the like. It is necessary to prevent adhesion and retention. Therefore, a vertical roller mill used for pulverizing wet raw materials such as slag often employs a center chute system in which raw material charging chutes are arranged in a vertical direction.

  On the other hand, dry materials such as clinker hardly contain moisture and have low adhesion to surrounding structures and the like, so that there is almost no problem that the material adheres and stays on the inner surface of the material charging chute when the material is charged. Rather, in the case of dry raw materials such as clinker, the raw material released from the lower end opening of the raw material charging chute and colliding with the rotary table jumps on the rotary table due to the impact force at the time of collision, and the gap between the grinding roller and the rotary table There is a problem that the supply of the raw material to the water becomes unstable and the pulverization efficiency of the raw material decreases.

  In particular, in the case of the center chute type material charging chute, the material dropping speed is larger than that of the side chute type material charging chute, and therefore, there is a problem of destabilization of the material supply due to the jumping of the dry material on the rotary table. Become serious.

  Therefore, in a vertical roller mill used for dry raw material crushing processing, the side chute type raw material is used to reduce the speed of the raw material when it reaches the rotary table and to suppress the jumping of the raw material on the rotary table. In many cases, a shooting chute is used.

Japanese Utility Model Publication No. 3-90634

  As described above, a vertical roller mill with a center chute-type raw material input chute is suitable for wet raw materials, while a vertical roller mill with a side-chute type raw material input chute is suitable for dry raw materials. There is a demand for users who pulverize both wet and dry raw materials to use a single vertical roller mill for both processes.

  However, in the conventional vertical roller mill, it is extremely difficult to appropriately adjust the wet raw material treatment and the dry raw material treatment so that they can be operated without any trouble.

  In particular, as the vertical roller mill becomes larger, the length of the raw material charging chute becomes longer. For this reason, when a side chute-type raw material charging chute is used to input a highly adhering wet raw material, the problem of adhesion and retention of the raw material in the raw material charging chute becomes more serious.

  Further, as the vertical roller mill becomes larger, the falling speed of the raw material when passing through the raw material charging chute and reaching the rotary table increases. For this reason, the jumping of the dry raw material with little moisture on the rotary table becomes severe, and the problem of instability of the raw material supply becomes more serious.

  The present invention has been made in view of the above-described problems of the prior art, and is a vertical roller mill that can be operated without any problem by appropriately changing a part of its structure during wet raw material treatment and dry raw material treatment. The purpose is to provide.

  In order to solve the above problems, a vertical roller mill according to a first aspect of the present invention includes a rotary table, a pulverizing roller for biting and pulverizing an object to be crushed between the rotary table, and the rotary table. A raw material charging chute having a lower end opened above the raw material charging chute, and a raw material speed reducing means for reducing the speed of the raw material falling inside the raw material charging chute, wherein the raw material speed reducing means is a lower part of the raw material charging chute And a baffle member including a collision surface on which a raw material falling in the raw material charging chute collides.

  The second aspect of the present invention is characterized in that the collision surface extends in a direction crossing the extending direction of the lower portion of the raw material charging chute.

  The third aspect of the present invention is characterized in that the collision surface extends in a horizontal direction.

  According to a fourth aspect of the present invention, the raw material reduction means has at least two baffle members, and one of the at least two baffle members is different from the other one of the at least two baffle members. It is arranged at a height.

  According to a fifth aspect of the present invention, when viewed in the extending direction of the raw material charging chute, substantially the entire passage cross section of the raw material charging chute is covered by the at least two baffle members. To do.

  A sixth aspect of the present invention is characterized in that a pair of openings through which both end portions of the baffle member are inserted are formed in the lower portion of the raw material charging chute.

  In a seventh aspect of the present invention, a sealing member that integrally seals one of the pair of openings at the lower portion of the raw material charging chute so as to be openable is integrally provided at one end of the baffle member. It is characterized by that.

  In an eighth aspect of the present invention, the one of the pair of openings at the lower portion of the raw material charging chute can be configured such that the baffle member can be inclined while the baffle member is inserted therein. It is characterized by being formed with a dimension larger than the outer dimension of the baffle member.

  According to a ninth aspect of the present invention, one of the pair of openings at the lower portion of the raw material charging chute is releasably sealed, and one end of the baffle member is inserted and supported. It further has a sealing member in which an opening is formed.

  A tenth aspect of the present invention is characterized in that the lower portion of the raw material charging chute is detachably attached to a main body portion of the raw material charging chute.

  The eleventh aspect of the present invention further includes a mill casing that houses the rotary table and the crushing roller, and the raw material charging chute extends along the rotation axis of the rotary table inside the mill casing. It is characterized by that.

  ADVANTAGE OF THE INVENTION According to this invention, the vertical roller mill which can be operate | moved without trouble by changing a part of the structure suitably at the time of wet raw material processing and the dry raw material processing can be provided.

The longitudinal cross-sectional view which showed typically schematic structure of the vertical roller mill by one Embodiment of this invention. The typical longitudinal cross-sectional view which expanded and showed the lower end part of the raw material input chute of the vertical roller mill shown in FIG. 1 with the rotary table and the crushing roller. The front view which expanded and showed the lower end part of the raw material input chute of the vertical roller mill shown in FIG. The rear view which expanded and showed the lower end part of the raw material input chute of the vertical roller mill shown in FIG. The front view which showed the lower end part of the raw material input chute of the vertical roller mill shown in FIG. 3 in the state which removed the raw material deceleration means. Sectional drawing along the VI-VI line of FIG. The front view which showed the base end side sealing member integrated in the base end side of the upper side baffle member. The front view which showed the front end side sealing member in which the edge part support opening by which the front-end | tip part of an upper baffle member was inserted and supported was formed. Sectional drawing along the IX-IX line of FIG. It is the front view which showed the base end side sealing member integrated in the base end side of the lower baffle member, (a) shows the left base end side sealing member, (b) is the right base end A side sealing member is shown. It is the front view which showed the front end side sealing member in which the edge part support opening by which the front end part of a lower baffle member was inserted and supported was formed, (a) shows the left side front end side sealing member, b) shows the right end side sealing member.

  Hereinafter, a vertical roller mill according to an embodiment of the present invention will be described with reference to the drawings.

  As shown in FIGS. 1 and 2, the vertical roller mill 1 according to the present embodiment bites the raw material between the rotary table 2 and the rotary table 2 on which the raw material (object to be crushed) is supplied. Are provided with a plurality of crushing rollers 3 for crushing. The turntable 2 is driven to rotate about the vertical rotation axis L0.

  The plurality of crushing rollers 3 are arranged at equiangular intervals on a virtual circumference centered on the vertical rotation axis L <b> 0 of the turntable 2. Each of the plurality of crushing rollers 3 is pressed toward the working surface (crushing surface) 2a of the rotary table 2 by a roller pressing mechanism 4 having a drive source such as a hydraulic cylinder.

  The vertical roller mill 1 includes a rotation drive source 5 and a speed reducer 6 for the rotary table 2, and the rotary table 2 is installed above the speed reducer 6.

  The rotary table 2 and the grinding roller 3 are covered with a mill casing 7. The supply of the raw material to the turntable 2 is performed through a raw material supply chute 8 disposed through the mill casing 7. The raw material supply chute 8 extends along the vertical rotation axis L <b> 0 of the turntable 2. A raw material discharge opening 8 b formed in the lower end portion 8 a of the raw material supply chute 8 opens above the center portion of the turntable 2.

  A separator 9 is provided above the rotary table 2. Of the raw materials released radially outward from the turntable 2 by centrifugal force, the raw material pulverized to a size smaller than a predetermined particle size (particle size) is passed through a hot air duct (not shown) into the mill casing 7. Is blown up by the hot air supplied to the separator 9 and transferred to the separator 9.

  The separator 9 is rotationally driven by a separator driving device 10 composed of an electric motor or the like, and among the raw materials blown up by hot air, only the raw material (fine powder) finer than the desired particle size (particle size) is placed on the upper portion of the mill casing 7. It discharges from the provided fine powder discharge duct (not shown). On the other hand, the raw material (coarse powder) coarser than the desired particle size (particle size) is separated by the separator 9 and returned onto the rotary table 2 via the funnel-shaped member (inner cone) 11, and the pulverizing roller 3 and the rotary table. 2 and is crushed again.

  The vertical roller mill 1 is provided with a recovery casing 12 for recovering a raw material that has not been blown up by hot air among the raw materials released around the rotary table 2 by centrifugal force accompanying the rotation of the rotary table 2. The recovery casing 12 has an outer diameter larger than that of the turntable 2 and has an annular shape as a whole. The raw material recovered in the recovery casing 12 is returned to the turntable 2 via an external circulation line (not shown) and pulverized again.

  As shown in FIG. 2, the lower end portion 8 a of the raw material supply chute 8 is exposed to the outside from the lower end opening of the funnel-shaped member 11, and is detachably attached to the main body portion 8 c of the raw material supply chute 8.

  As shown in FIGS. 3 to 5, three openings 13 and 14 are formed in the lower end portion 8 a of the raw material supply chute 8 on the front side and the back side, respectively. The opening 13 on the upper front stage corresponds to the opening 14 on the upper rear stage, the opening 13 on the lower right side of the front corresponds to the opening 14 on the lower right side of the lower face, and the opening 13 on the left side of the lower front stage corresponds to the opening 14 on the right side of the lower rear stage. It corresponds. FIG. 5 shows three openings 13 on the front side, but three openings 14 are similarly formed on the back side.

  As shown in FIG. 3, each of the three front-side openings 13 is sealed by each of the three front-side sealing members 15. Each front-side sealing member 15 is detachably attached to the lower end portion 8a of the raw material supply chute 8 by a bolt 15a. The opening 13 on the front side can be opened by loosening the bolt 15a and removing the front side sealing member 15. Each front side sealing member 15 is provided with a handle 16 to facilitate handling of the front side sealing member 15 by an operator.

  As shown in FIG. 4, each of the three openings 14 on the back side is sealed by each of the three back side sealing members 17. Each back side sealing member 17 is detachably attached to the lower end portion 8a of the raw material supply chute 8 by a bolt 17a. The opening 14 on the back side can be opened by loosening the bolt 17 a and removing the back side sealing member 17. A U-shaped end support opening 17 b is formed in the back side sealing member 17.

  As shown in FIGS. 6 to 8, the proximal end 18 a of the upper baffle member 18 having a U-shaped cross section is fixed to the front sealing member 15 that seals the opening 13 in the upper front. . The front end 18b of the upper baffle member 18 is inserted into the end support opening 17b of the back side sealing member 17 that seals the opening 14 on the upper back.

  As shown in FIGS. 9 to 11, the front-side sealing member 15 that seals the opening 13 on the lower right side of the front surface is fixed with the base end 19a of the lower right baffle member 19 having a U-shaped cross section. ing. The front end 19b of the lower right baffle member 19 is inserted into the end support opening 17b of the back side sealing member 17 that seals the opening 14 on the lower right side of the back.

  Similarly, a proximal end 19a of a lower left baffle member 19 having a U-shaped cross section is fixed to a front sealing member 15 that seals the opening 13 on the lower left side of the front. The front end 19b of the lower left baffle member 19 is inserted into the end support opening 17b of the back side sealing member 17 that seals the opening 14 on the lower left side of the back.

  As shown in FIGS. 6 and 9, each of the upper baffle member 18 and the lower baffle member 19 extends in the extending direction of the lower end portion 8a of the raw material charging chute 8 (in this example, the vertical rotation axis L0 of the turntable 2). It has collision surfaces 18c and 19c extending in the horizontal direction perpendicular to the extending direction. When viewed in the extending direction of the lower end portion 8 a of the raw material charging chute 8, one upper baffle member 18 and two lower baffle members 19 cover substantially the entire passage section of the raw material charging chute 8.

  The raw material falling in the raw material charging chute 8 collides with the respective collision surfaces 18c and 19c of the upper baffle member 18 and the lower baffle member 19 in front of the raw material discharge port 8b of the lower end portion 8a of the raw material charging chute 8. Since the collision surfaces 18c and 19c extend in the horizontal direction, a raw material deposition layer is formed on the collision surfaces 18c and 19c, and the subsequent raw material collides with the deposition layer on the collision surfaces 18c and 19c. Thus, since the deposited layer of the raw material covers the collision surfaces 18c and 19c, wear of the upper and lower baffle members 18 and 19 due to the collision of the raw material is suppressed.

  As described above, the upper and lower baffle members 18 and 19 cover substantially the entire passage section of the raw material charging chute 8, so that most of the raw material falling in the raw material charging chute is the collision surfaces 18c and 19c or the collision surface. It collides with the raw material deposited on 18c, 19c. By colliding with the collision surfaces 18c and 19c or the material deposited on the collision surfaces 18c and 19c, the speed of the material falling in the material charging chute 8 is reduced.

  As described above, the upper and lower baffle members 18 and 19 including the collision surfaces 18c and 19c reduce the speed of the raw material falling in the raw material charging chute 8 immediately before the raw material discharge port 8b of the raw material charging chute 8. Functions as a means. Since the distance from the raw material deceleration means to the rotary table 2 is short, even if the falling speed of the raw material is accelerated after passing through the raw material deceleration means, the speed of the raw material when reaching the rotary table 2 is not so high.

  For this reason, even when processing a dry raw material containing almost no water, such as a clinker, the raw material reduction means composed of the upper and lower baffle members 18 and 19 reduces the falling speed of the raw material and reaches the turntable 2. The raw material speed at the time is suppressed. As a result, the jumping of the raw material at the time of the collision with the rotary table 2 is suppressed, and the unstable supply of the raw material can be prevented.

  On the other hand, when the wet raw material such as slag is processed by the vertical roller mill 1 according to the present embodiment, the upper and lower baffle members 18 and 19 are removed from the lower end portion 8 a of the raw material supply chute 8. This detaching operation can be easily performed by removing the bolt 15a that fixes the front side sealing member 15, grasping the handle 16, and pulling out the baffle members 18, 19 together with the front side sealing member 15.

  As shown in FIG. 5, the front side opening 13 formed in the lower end portion 8 a of the raw material supply chute 8 can incline the baffle members 18, 19 with the baffle members 18, 19 inserted therein. As described above, the baffle members 18 and 19 are formed with dimensions larger than the outer dimensions.

  Therefore, when the raw material is deposited on the baffle members 18 and 19 by the dry raw material processing performed in advance, the baffle members 18 and 19 are passed through the front side opening 13 of the lower end portion 8a of the raw material supply chute 8. Before pulling out, the baffle members 18 and 19 are once inclined to drop the raw material deposited thereon. Thereby, since the handling weight at the time of the extraction operation | work of the baffle members 18 and 19 reduces, a worker's load can further be reduced.

  When the upper and lower baffle members 18 and 19 are removed, the three front side openings 13 of the lower end portion 8a of the raw material supply chute 8 are sealed with blind plates (not shown). In addition, the three back side openings 14 at the lower end 8a of the raw material supply chute 8 are also sealed with a blind plate (not shown) having no openings, instead of the back side sealing member 17 in which the end support openings 17b are formed. Stop.

  Further, when performing maintenance of the vertical roller mill 1 according to the present embodiment, a large working space can be secured above the turntable 2 by removing the lower end portion 8a of the raw material supply chute 8 from the main body portion 8c. .

  As described above, according to the vertical roller mill 1 according to the present embodiment, the dry raw material is processed by mounting the baffle members 18 and 19 constituting the raw material reduction means inside the lower end portion 8a of the raw material charging chute 8. On the other hand, when the wet raw material is processed, the baffle members 18 and 19 can be easily removed from the lower end portion 8a of the raw material supply chute 8. Thereby, the vertical roller mill 1 that can be operated without any trouble by appropriately changing a part of the structure between the wet raw material treatment and the dry raw material treatment is provided.

  In particular, according to the vertical roller mill 1 according to the present embodiment, each of the wet raw material and the dry raw material can be pulverized without hindrance even when the raw material supply chute 8 becomes longer as the mill becomes larger. That is, even when the material dropping speed increases due to the lengthening of the material charging chute 8, the material speed at the time of reaching the turntable 2 can be sufficiently reduced by the material deceleration means. In addition, by adopting the center chute type raw material charging chute 8 extending in the vertical direction, even when the raw material charging chute 8 is lengthened, adhesion and retention of wet raw material on the inner surface of the raw material charging chute 8 are ensured. Can be prevented.

  Further, in the vertical roller mill according to the present embodiment, when the dry raw material treatment and the wet raw material treatment are switched, only the baffle members 18 and 19 are attached and detached without removing the lower end portion 8a of the raw material supply chute 8. Therefore, the work load at the time of switching can be reduced.

  In the above-described embodiment, the baffle members 18 and 19 including the collision surfaces 18c and 19c extending in the horizontal direction are used as the raw material reduction means, but the extending direction of the collision surface is not limited to the horizontal direction. It may be inclined from the horizontal direction.

  Moreover, in the embodiment mentioned above, although the three baffle members 18 and 19 are installed as a raw material deceleration means, the number of baffle members installed is not limited to three. The raw material deceleration means in the present invention can be configured by arranging one of at least two baffle members and the other one of at least two baffle members at different heights.

  Further, in the above-described embodiment, the bolts 15a and 17a are employed as the attachment / detachment mechanism of the raw material reduction means, but in addition to the bolt, a fitting structure of a pin and a pin hole may be employed, or A structure in which the above-described baffle members 18 and 19 are placed over the pair of front and rear opening edges formed on the side surface of the lower end portion 8a of the raw material supply chute 8 and simply placed may be employed.

  In the above-described embodiment, the baffle members 18 and 19 are installed at the lower end portion 8a of the raw material supply chute 8. However, as long as the material deceleration effect by the baffle members 18 and 19 can be ensured, the baffle members 18 and 19 are above the lower end portion 8a. The baffle members 18 and 19 can also be installed at the positions.

DESCRIPTION OF SYMBOLS 1 Vertical roller mill 2 Rotary table 2a Working surface (grinding surface) of rotary table
DESCRIPTION OF SYMBOLS 3 Crushing roller 4 Roller pressing mechanism 5 Rotating table rotational drive source 6 Rotating table speed reducer 7 Mill casing 8 Raw material charging chute 8a Raw material charging chute lower end 8b Raw material charging chute raw material discharge port 8c Raw material charging chute main body 9 Separator 10 Separator drive device 11 Funnel-shaped member (inner cone)
DESCRIPTION OF SYMBOLS 12 Recovery casing 13 Front side opening 14 Back side opening 15 Front side sealing member 15a Front side sealing member bolt 16 Front side sealing member handle 17 Back side sealing member 17a Back side sealing member bolt 17b End Support opening 18 Upper baffle member 18a Upper end baffle member end 18b Upper end baffle tip 18c Upper baffle impact surface 19 Lower baffle member 19a Lower baffle base end 19b Lower baffle member 19b 19c Front end 19c Colliding surface of lower baffle member L0 Vertical rotation axis of rotary table

Claims (11)

A rotating table,
A crushing roller for biting and crushing an object to be crushed with the rotary table;
A raw material charging chute having a lower end opened above the rotary table;
A raw material deceleration means for reducing the speed of the raw material falling inside the raw material charging chute, and
The raw material speed reducing means includes a baffle member provided inside the lower portion of the raw material charging chute so as to be detachable from the raw material charging chute and including a collision surface on which the raw material falling in the raw material charging chute collides. Type roller mill.   The vertical roller mill according to claim 1, wherein the collision surface extends in a direction crossing an extending direction of the lower portion of the raw material charging chute.   The vertical roller mill according to claim 2, wherein the collision surface extends in a horizontal direction.   The raw material reduction means includes at least two baffle members, and one of the at least two baffle members and the other one of the at least two baffle members are arranged at different heights. Item 4. The vertical roller mill according to any one of items 1 to 3.   The vertical roller mill according to claim 4, wherein when viewed in the direction in which the raw material charging chute extends, the at least two baffle members cover substantially the entire passage section of the raw material charging chute.   The saddle type roller mill according to any one of claims 1 to 5, wherein a pair of openings through which both end portions of the baffle member are inserted are formed in the lower portion of the raw material charging chute.   The saddle type according to claim 6, wherein a sealing member that integrally seals one of the pair of openings at the lower portion of the raw material charging chute so as to be openable is integrally provided at one end of the baffle member. Roller mill.   One of the pair of openings in the lower portion of the raw material charging chute is larger than the outer dimension of the baffle member so that the baffle member can be inclined with the baffle member inserted therein. The vertical roller mill according to claim 7, which is formed by:   One of the pair of openings at the lower portion of the raw material charging chute is releasably sealed, and a sealing member is formed with an end support opening through which one end of the baffle member is inserted and supported. Furthermore, the vertical roller mill as described in any one of Claims 6 thru | or 8.   The vertical roller mill according to any one of claims 1 to 9, wherein the lower portion of the raw material charging chute is detachably attached to a main body portion of the raw material charging chute. A mill casing that houses the rotary table and the crushing roller;
The vertical roller mill according to any one of claims 1 to 10, wherein the raw material charging chute extends along a rotation axis of the rotary table inside the mill casing.

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