KR100835274B1 - Scrapper for depulverized coal exhaustion for coal pulverizer - Google Patents

Abstract

A pulverized coal discharge scraper for a coal pulverizer is provided to exchange only wear-resistant materials of a part of high abrasion level by changing the shape and combination structure of the wear-resistant material. A pulverized coal discharge scraper(300) installed at a rotary shaft in a coal pulverizer to discharge pulverized coal by centrifugal force is composed of a bracket(330) fixed at the rotary shaft; a body(310) mounted on the bracket; a combining pin(350) fixing the body and the bracket; a bush(340) inserted into joining holes(325,327) of the body to reduce friction force with the combining pin; a wear-resistant plate(320) installed at a plate member(313) of the body; and first and second wear-resistant materials(323,329) installed at the wear-resistant plate to come into contact with the pulverized coal. The first and second wear-resistant materials are installed at the upper and lower parts on one surface of the wear-resistant plate while matching the sections with each other. When the wear-resistant plate is viewed from the front side, the first wear-resistant materials are installed on the right lower end and the left upper end. The second wear-resistant materials are installed on the left lower end and the right upper end.

Description

Scraper for Depulverized Coal exhaustion for Coal Pulverizer

1 is a cross-sectional view of a coal grinder,

2 is an exploded perspective view of a scraper according to the prior art,

3 is an exploded perspective view of a scraper according to a preferred embodiment of the present invention,

4 is an assembled perspective view of a scraper according to a preferred embodiment of the present invention,

5 is a cross-sectional view of a scraper according to a preferred embodiment of the present invention;

6 is a longitudinal sectional view of the scraper according to a preferred embodiment of the present invention.

<Description of Symbols for Main Parts of Drawings>

300: scraper 310: main body

311: centerline 313: plate member

315: pipe 317: through hole

320: wear-resistant plate 323: first wear-resistant material

325: first fastening hole 327: second fastening hole

329: second wear resistant material 330: bracket

333: top plate 335: bottom plate

340: bush 343: first coupling hole

345: second coupling hole 350: coupling pin

355: locking projection 360: fixing cover

365: third coupling hole 380: second prevention plate

The present invention relates to a pulverized coal discharge scraper for a coal mill. More specifically, it is possible to change the structure in which the coupling pins are coupled to prevent the coupling pins from being separated by physical factors, and to change the shape and coupling structure of the wear-resistant material to provide an economical and stable pulverized coal discharge scraper for coal mills. will be.

Coal, used as fuel in coal-fired power plants, enters the boiler and burns. After the water is heated and changed to the steam state by the burned heat, high temperature and high pressure steam is generated by rotating the blades of the turbine. Here, coal is pulverized into coal in order to increase combustion efficiency by combining with oxygen in the air that is additionally input into the boiler. A coal pulverizer serves to crush coal.

1 is a cross-sectional view of a coal mill and FIG. 2 is an exploded perspective view of a scraper according to the prior art.

The coal mill 100 includes a center pipe 110, a particle size sorter 120, a roller 140, and a scraper 170. In the upper center of the housing 150 forming the appearance of the coal mill 100, the center pipe 110 for introducing the raw coal (not shown) supplied from the feeder (not shown) into the housing 150 is a coal mill ( 100 penetrates into the inside, and the raw coal inputted into the center pipe 110 falls to the roller 140 located at the lower side, so that the roller 140 or the bottom surface 130 rotates, and the roller 140 and the bottom surface 130 are rotated. The raw coal is pulverized into pulverized coal between

The pulverized coal pulverized by the roller 140 is moved to the upper part where the particle size classifier 120 is located by the high pressure air injected into the lower part of the housing 150, and is input into the particle size classifier 120. When the pulverized coal inputted by centrifugal force is heavy, it is discharged to the outside of the particle size classifier 120 and moved back to the lower side, and if the weight is moderate, the pulverized coal outside the coal mill 100 through the pulverized coal tube 190 located at the upper end of the housing 150. It is discharged to and supplied to a boiler (not shown).

Here, the roller 140 has three radially centered on the rotating shaft 180 on the bottom surface 130. The raw coal dropped through the center pipe 110 is pulverized by the roller 140 and the rotating bottom surface 130. The grinding process between the roller 140 and the roller 140 by the centrifugal force of the bottom surface 130 during the grinding. Coal that is not completely crushed (hereinafter referred to as pulverized coal) exits to the formed space A and is located outside the surface B where the roller 140 and the bottom surface 130 come into contact with each other. Fall down through the ball (160).

A lower portion of the bottom surface 130 is provided with a scraper 170 for discharging the pulverized coal into a separate storage tank (not shown). The scraper 170 rotates together with the bottom surface 130 and is provided radially on the rotation shaft 180.

Conventional scraper 170 is configured to include a main body 210, wear-resistant material 220, bracket 230, coupling pin 240 and the bush 250. The bracket 230 serves to connect the rotating shaft 180 and the main body 210 and is fixed to the rotating shaft 180 with a bolt. The main body 210 has a shape in which a hollow pipe is integrally formed on one side of the plate member 215, and a through hole 217 is formed, and the wear-resistant material 220 is formed on one side of the main body 210 by bolts and nuts. Is coupled by, bracket 230 is formed in the upper plate 233 and the lower plate 235, respectively, the coupling hole 237, the upper plate 233 and the lower plate 235 is formed integrally with the fixing plate (239).

The coupling holes 237 formed in the upper plate 233 and the lower plate 235 are respectively inserted with a pipe-shaped bush 250 and the through-holes 217 and the coupling holes 237 are positioned to coincide with the coupling pins 240. The coupling pin 240 is fixed by the fastening force of the fixing bolt 213 by fastening the fixing bolt 213 to the screw coupling hole 215 formed to penetrate through the outer circumferential surface of the through hole 217. The upper portion of the upper plate 233 and the one side of the bracket 230, the cover 260 for preventing the introduction of foreign matter, respectively, is coupled by a bolt.

The scraper 170 is exposed to severe friction, impact and vibration while scraping the pulverized coal, the fastening of the fixing bolt 213 is released by this physical factor, there is a fear that the coupling pin 240 falls down. When the coupling pin 240 falls, there is a problem that the main body 210 is separated from the bracket 230.

In addition, the pulverized coal is concentrated on the lower surface C of the outer surface of the scraper 170 which is far from the bracket 230 by centrifugal force, so that the wear of the 'C' portion is most severe. Therefore, the 'C' part is the fastest wear, but because there is no large wear other than the 'C' part because the wear-resistant material 220 is formed integrally discarded and used by installing a new wear-resistant material 220 scraper There was a costly problem in using (170).

In order to solve this problem, the present invention, by changing the structure in which the coupling pin is bonded to prevent the coupling pin from being separated by physical factors and to change the shape and coupling structure of the wear-resistant material to provide an economical and stable scraper The purpose is.

In order to achieve the above object, the present invention provides a scraper which is provided on a rotating shaft inside a coal mill and discharges pulverized coal by centrifugal force, the bracket being fixed to the rotating shaft; A body mounted to the bracket; Coupling pins to fix the body and the bracket; A bush inserted into the fastening hole of the main body to reduce friction with the coupling pin; An anti-wear plate attached to the plate-shaped member of the main body; And a first wear material and a second wear material mounted on the wear plate to be in contact with the pulverized coal, and each of the first wear material and the second wear material on one side of the wear plate on the top and the bottom thereof. The pulverized coal for coal crusher, characterized in that it is mounted to match the cross section, but when the wear plate is viewed from the front, the first wear material is mounted on the lower right and upper left, and the second wear material is mounted on the lower left and upper right. Provide an exhaust scraper.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First of all, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals have the same reference numerals as much as possible even if displayed on different drawings. In addition, in describing the present invention, when it is determined that the detailed description of the related well-known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

Figure 3 is an exploded perspective view of the scraper according to a preferred embodiment of the present invention, Figure 4 is an assembled perspective view of the scraper according to a preferred embodiment of the present invention, Figure 5 is a cross-sectional view of the scraper according to a preferred embodiment of the present invention, Figure 6 is Longitudinal sectional view of a scraper according to a preferred embodiment of the present invention.

Scraper 300 according to a preferred embodiment of the present invention comprises a body 310, wear-resistant plate 320, bracket 330, bush 340 and the coupling pin 350.

The main body 310 is provided with a pipe 315 integrally on one side of the plate-like member 313, the through hole 317 is formed in the pipe 315. A plurality of first fastening holes 325 are formed on the plate member 313 side of the main body 310. The first fastening hole 325 is formed to mount the wear-resistant plate 320 on one surface of the plate-shaped member 313, the second fastening hole 327 is also formed in the same position in the wear-resistant plate 320 to the main body The 310 and the wear resistant plate 320 are coupled by bolts and nuts.

Here, the first fastening hole 325 is formed in the plate member 313 so that the first fastening holes 325 are symmetrical with each other or positioned above the center line 311 with respect to the virtual horizontal center line 311. The upper and lower sides of the wear-resistant plate 320 can be switched on to be mounted on.

Two types of wear-resistant materials 323 and 329 are provided on one surface of the wear-resistant plate 320, and the first wear-resistant material 323 and the second wear-resistant material 329 each have a cross section at the top and the bottom thereof. Mount to match. The material of the wear resistant materials 323 and 329 is most preferably made of chromium molybdenum steel (SK-HARD42), and the first wear resistant material 323 and the second wear resistant material 329 are compared with each other. The wear material 323 is thicker and has a higher height than the second wear resistant material 329. The first wear resistant material 323 is mounted on the lower right and upper left, and the second wear resistant material 329 is mounted on the lower left and upper right when the wear resistant plate 320 is viewed from the front.

The reason why the wear-resistant material (323, 329) is located as above is that the pulverized coal is concentrated on the lower portion (D) of the outer surface of the wear-resistant plate 320, which is far from the bracket 330 by centrifugal force. Wear is most severe, so the first wear-resistant material 323 is located at the 'D' portion, so that the first wear-resistant material 323 is positioned in the same position even if the top and bottom of the wear-resistant plate 320 is mounted To do this.

In addition, by attaching the wear-resistant materials (323, 329) separated into four parts, even if any one of the four wear-resistant materials (323, 329) is worn, replacing only worn wear materials (323, 329) It is easy to maintain as it can be used like this.

On the other hand, the method of mounting the body 310 to the bracket 330 is as follows. A through hole 317 formed in the pipe 315 is inserted with a bush 340 inserted between the metal and the metal to reduce frictional resistance. Coupling holes 343 and 345 are formed in the upper plate 333 and the lower plate 335 of the bracket 330, respectively, and the coupling pins 350 are inserted into the coupling holes 343 and 345. Both ends of the coupling pin 350 forms a locking protrusion 355 and forms a first coupling hole 343 in a shape corresponding to the shape of the locking protrusion 355. The shape of the locking projection 355 is not limited as long as it is a shape that prevents rotation when the outer peripheral surface of the end portion of the coupling pin 350 having a cylindrical shape is inserted into the first coupling hole 343. Therefore, one end of the coupling pin 350 is inserted into the first coupling hole 343, and the second coupling hole 345 is formed to be similar to the outer diameter of the coupling pin 350 so that the coupling pin 350 is coupled to the second. Allow insertion through ball 345.

The through hole 317 is positioned between the first coupling hole 343 and the second coupling hole 345 in a state where the bush 340 is inserted into the through hole 317, and the coupling pin is connected through the second coupling hole 345. After the 350 is inserted, the fixing cover 360 and the first prevention plate 370 are fixed to the upper plate 333. The fixing cover 360 is a plate-shaped member to form a third coupling hole 365 having the same shape as the cross section of the locking protrusion 355 in the fixing cover 360 to fix the coupling pin 350. The first prevention plate 370 is a member that prevents foreign matter from flowing between the bush 340 and the coupling pin 350, and may be formed integrally with the fixing cover 360 to fix the foreign material.

The scraper 300 mounted as described above serves as a stopper for preventing the shape of the first coupling hole 343 from moving the coupling pin 350 downward, and at the same time, fixing the coupling pin 350 in the rotational direction. Do it. On the other hand, one side of the bracket 330 is equipped with a second prevention plate 380 to prevent the pulverized coal is introduced into the bracket 330 and at the same time to prevent direct friction with the pulverized coal to increase the durability.

The above description is merely illustrative of the technical idea of the present invention, and those skilled in the art to which the present invention pertains may make various modifications and changes without departing from the essential characteristics of the present invention. Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

As described above, according to the present invention, by changing the structure in which the coupling pin is bonded to prevent the coupling pin from being separated by physical factors, and change the shape and coupling structure of the wear-resistant material only wear-resistant material of high wear In order to replace the upper and lower wear-resistant plate to replace the economical use of scraper and maintenance effect.

Claims (6)

In the scraper which is provided on the rotating shaft inside the coal mill to discharge the pulverized coal by centrifugal force, A bracket fixed to the rotating shaft; A main body mounted to the bracket; Coupling pins to fix the body and the bracket; A bush inserted into the fastening hole of the main body to reduce friction with the coupling pin; An anti-wear plate attached to the plate member of the main body; And And a first wear material and a second wear material mounted on the wear resistant plate and in contact with the pulverized coal. The first wear resistant material and the second wear resistant material are mounted on one surface of the wear resistant plate so as to coincide with the cross section at the top and the bottom thereof, respectively, and the wear resistant plate is located at the lower right and upper left when viewed from the front. Mounting the first wear material, and the second crushing coal discharge scraper for the coal mill, characterized in that for mounting the second wear resistant material on the lower left and upper right. The method of claim 1, The pulverized coal discharge scraper for coal crusher, characterized in that the engaging projection is formed on the outer peripheral surface of both ends of the coupling pin and the first coupling hole is formed in the lower plate of the bracket to correspond to the shape of the locking projection. The method of claim 1, Forming a first fastening hole and a second fastening hole in the plate-shaped member and the wear-resistant plate of the main body, respectively, and formed to be coupled to the plate-shaped member by switching up and down of the wear-resistant plate Pulverized coal discharge scraper. The method of claim 1, After fixing the bracket and the main body by the coupling pin is provided with a fixing cover for fixing the coupling pin, characterized in that the fixing cover formed a third engaging hole of the engaging projection shape formed in the coupling pin A pulverized coal discharge scraper for a coal mill. The method of claim 4, wherein The pulverized coal discharge scraper for the coal mill, characterized in that provided with a first preventing plate on the upper portion of the fixing cover in order to prevent foreign matters between the coupling pin and the bush. The method of claim 1, Grinding coal discharge scraper for a coal mill, characterized in that provided with a second preventing plate for preventing the inflow of foreign matter on one side of the bracket.

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