JP7380280B2 - Grizzly bars and wear-resistant sieves equipped with Grizzly bars - Google Patents

Description

The present invention relates to a sieve (so-called "grizzly") for separating high-temperature fired products into large lumps and pellets of granular material. Specifically, it is a "sieve (Grizzly)" that is installed at the exit of an industrial furnace, etc. and is expected to be used in a high-temperature environment of 700 degrees Celsius or higher, and is a metal rod with wear-resistant protection parts on the top and sides. The invention relates to a so-called "grizzly bar") and an abrasion-resistant sieve comprising such a grizzly bar.

In order to separate coarse materials such as huge lumps that are mixed in the high-temperature waste discharged from industrial furnaces that perform various heat treatments, abrasion-resistant A large "sieve" (herein referred to as a "wear-resistant sieve") is used.

Generally, an abrasion resistant sieve has a structure in which grizzly bars made of metal bar-shaped members are arranged in parallel to each other (see FIG. 1). The wear-resistant sieve shown in the figure is installed at the discharge end of a rotary kiln that discharges zinc oxide burnt ore that has reached a high temperature of about 900 to 1200°C, for example, in the process of manufacturing zinc oxide ore using the Wertz process. It is used as a device to separate discharged high-temperature burnt ore into pellets, which can be transported directly to the next process, and large lumps, which cannot be transported. The large chunks that remain on the grizzly bar and are separated and collected are discharged to a dedicated outlet.

Incidentally, the zinc oxide sintered ore still maintains a high temperature state of about 700 to 900° C. even at the time of discharge. As typified by this example, the grizzly bars constituting the wear-resistant sieve are normally constantly exposed to violent collisions with rapidly falling high-temperature burnt ore or lumps. Therefore, a protective member (herein referred to as a "wear-resistant protective cover") that is resistant to high temperature brittleness is usually installed on the top side.

As such a "wear-resistant protective cover," for example, a grizzly bar having a structure in which a ceramic member is fixed to the upper part of the grizzly bar body has been proposed (see Patent Document 1). However, since this wear-resistant protective cover is made of ceramic, it cannot have the same impact resistance as a metal-based wear-resistant material. Therefore, for example, as mentioned above, the impact resistance is insufficient for use in locations where constant collisions with high-temperature lumps are expected, and there are significant restrictions on the range of usage conditions. .

Therefore, in places where constant collision with high-temperature lumps is expected, a triangular roof-like outer shape into which wear-resistant material 22 is cast is conventionally formed, as in the Grizzly bar 10B shown in FIG. A wear-resistant sieve equipped with a grizzly bar having a structure in which a wear-resistant protective cover is joined to a grizzly bar body 1 by a connecting metal fitting 6 and bolts 7, etc., has been widely used (see the figure in Patent Document 2). 5, see FIG. 5 of Patent Document 3).

However, in the grizzly bar 10B shown in FIG. 6, the side plate of the protective cover and the connecting hardware 6 for joining the protective cover are limited in the width of the gap between each bar on the side of the grizzly bar main body. It was merely covered, and its wear resistance was insufficient compared to the upper side.

Japanese Patent Application Publication No. 2002-219416 JP2018-161638A Japanese Patent Application Publication No. 2018-161639

The object of the present invention is to be fully usable, for example, in a high-temperature environment of 700°C or higher, where constant collisions with high-temperature lumps, etc. are expected; It is an object of the present invention to provide a grizzly bar having sufficient abrasion resistance even on its side surfaces, and an abrasion-resistant sieve equipped with such a grizzly bar.

As a result of extensive research, the inventor of the present invention has determined that, unlike the conventional structure in which a wear-resistant protective cover is placed over the Grizzly bar body, the present inventor sprayed an anti-wear agent directly onto the side of the Grizzly bar body. It was discovered that by making the abrasion resistant protective cover into an integrated structure, a sufficiently thick abrasion resistant layer can be formed on the sides of the grizzly bar to protect the sides that are severely damaged or worn, and the present invention was developed. was completed. Specifically, the present invention provides the following.

(1) A grizzly bar for a wear-resistant sieve, which includes a grizzly bar body made of a square prism-shaped metal rod, and a top-side wear-resistant part installed on the top surface, which is one longitudinal surface of the metal rod; a side wear-resistant part installed on both side surfaces in contact with the longitudinal direction of the top surface, and the top side wear-resistant part is made of a plurality of metal plates erected on the top surface of the Grizzly bar main body. and a wear-resistant material that is cast into the top-side formwork and joined to the Grizzly bar body, and the side-side wear-resistant part is formed on the side surface of the Grizzly bar body. A grizzly bar comprising a side formwork made of a plurality of metal plates erected, and a wear-resistant material cast into the side formwork and joined to the grizzly bar main body.

According to the invention (1), the grizzly bar body and the wear-resistant part are integrated by thermally spraying an anti-wear agent onto the grizzly bar body, instead of the conventional structure in which a wear-resistant cover part is placed on the grizzly bar body. The structure is as follows. This makes it possible to form a wear-resistant layer of sufficient thickness on the sides of the grizzly bar, even though there are restrictions on the gap width between each bar. Grizzly bars with wear resistance can now be obtained.

(2) The grizzly bar according to (1), wherein the side formwork is formed by arranging the metal plates in a grid pattern.

According to the invention (2), the degree of freedom and accuracy in designing the thickness of the side wear-resistant portion in the grizzly bar (1) is increased. Further, the work of forming the wear-resistant layer becomes easier. Thereby, the wear resistance of the grizzly bar side surface can be further improved.

(3) The grizzly bar according to (1) or (2), wherein the outer shape of the top side wear-resistant portion is formed in the shape of a gable roof.

According to the Grizzly bar (3), the outer shape of the wear-resistant portion on the top side is shaped like a gable roof. As a result, while maintaining the above-mentioned advantages of the invention (1) or (2), it is possible to avoid retention, accumulation, or adhesion of particulate matter, etc., which should be sieved to the lower part of the abrasion resistant sieve, on the grizzly bar, and to Abrasion resistance can be further improved.

(4) The grizzly bar according to any one of (1) to (3), wherein the wear-resistant material is a high-chromium cast iron-based wear-resistant material.

In the invention of (4), the wear-resistant plate material used in any of the grizzly bars of (1) to (3) is a general-purpose wear-resistant member that is easily available, and has heat resistance and wear resistance. A high-chromium cast iron-based wear-resistant material with excellent properties was used. This will increase the ease of manufacturing and maintenance work for the inventions (1) to (3), and will enable the above-mentioned effects of these inventions to be achieved more efficiently, including from the perspective of economic superiority. can be enjoyed.

(5) A wear-resistant sieve comprising the grizzly bar according to any one of (1) to (4).

In the invention of (5), the Grizzly bar of the abrasion resistant sieve is configured using any of the Grizzly bars of (1) to (4), thereby achieving the effect of any of the inventions of (1) to (4). By enjoying the above effects, it is possible to obtain an abrasion-resistant sieve having excellent abrasion resistance.

(6) A fired product sorting facility comprising: an industrial furnace for discharging fired products fired to a temperature of 700° C. or higher; and a wear-resistant sieve according to (5) installed on the discharge end side of the industrial furnace.

According to the invention (6), for example, at the discharge end of a rotary kiln that discharges fired products at a high temperature of 700°C or higher, the wear resistance of equipment that uses a wear-resistant sieve to sort out huge lumps in fired products. By improving this, operating efficiency can be improved.

(7) A production plant for zinc oxide ore by the Wertz process, in which the wear-resistant sieve described in (5) is installed on the discharge end side of the rotary kiln for the reduction roasting process and/or the rotary kiln for the drying and heating process. A zinc oxide ore manufacturing plant.

According to the invention (7), the wear-resistant sieve (5) can be used in a zinc oxide ore manufacturing plant using the Wertz method. According to this, by efficiently and economically recovering zinc from iron scrap, it will be possible to contribute to improving the productivity of the above-mentioned manufacturing plants, which greatly contribute to resource recycling in Japan, which does not have mineral resources. .

(8) The method for producing a grizzly bar according to any one of (1) to (4),
In both the top-side wear-resistant part and the side-side wear-resistant part, the wear-resistant material is bonded directly to the surface of the grizzly bar main body. performing a step of casting the wear-resistant material into the side formwork by thermal spraying;
How to make grizzly bars.

According to the invention (8), it is possible to manufacture a grizzly bar having sufficient wear resistance not only on the top surface but also on the side surfaces.

According to the present invention, it can be fully used in a high-temperature environment where constant collisions with high-temperature lumps, etc. are assumed, and in such an environment, not only the top part but also the side part can be used. It is also possible to provide a grizzly bar having sufficient abrasion resistance and an abrasion resistant sieve including such a grizzly bar.

FIG. 1 is a plan view of an abrasion resistant sieve equipped with a grizzly bar of the present invention. FIG. 2 is an elevational view schematically showing the overall structure of the wear-resistant sieve shown in FIG. 1. FIG. FIG. 1 is a front view showing the structure of the grizzly bar of the present invention. FIG. 2 is a side view of a grizzly bar of the present invention. FIG. 1 is a perspective view (partially enlarged view) of a grizzly bar of the present invention. FIG. 2 is a perspective view of a conventional grizzly bar in which a wear-resistant protective cover is installed on the top surface of the grizzly bar body.

Hereinafter, preferred embodiments of the Grizzly bar for an abrasion-resistant sieve of the present invention and the abrasion-resistant sieve provided with the Grizzly bar will be described.

The present invention provides a large industrial sieve that is installed at the discharge end of various industrial furnaces that discharge powdery, granular, or lumpy high-temperature waste and has the function of separating coarse waste from these wastes. It is a technology that can be widely applied in general. As a specific example, as described above, this technique can be preferably used on the discharge end side of a rotary kiln that discharges zinc oxide sintered ore in a process for producing zinc oxide ore by the Wertz method. However, the present invention is not limited to the embodiments described below. Other embodiments are also possible without departing from the gist of the present invention.

<Abrasion resistant sieve>
As shown in FIGS. 1 and 2, the wear-resistant sieve 100 has a sieve surface configured by a plurality of grizzly bars 10 arranged in parallel, and is capable of removing high-temperature powders, granules, and high-temperature lumps. This is a large sorting device that can sift through the Each grizzly bar 10 includes a grizzly bar body 1 which is a metal bar-shaped member, a top wear-resistant part 2 that covers the top and side surfaces of the grizzly bar body 1, and a side wear-resistant part 2. It has a configuration in which the section 3 is integrated. Details of the configuration of the grizzly bar 10 will be described later.

The wear-resistant sieve 100 is located at the discharge end side of an industrial furnace that discharges high-temperature exhaust, such as a rotary kiln that constitutes a zinc oxide ore production plant, at a position where the high-temperature exhaust can fall onto the grizzly bar 10. will be installed. The wear-resistant sieve 100 is usually installed so that the sieve surface formed by the grizzly bars 10 is an oblique surface, as shown in FIG.

In addition, as shown in FIG. 2, the wear-resistant sieve 100 is installed with the end of the grizzly bar 10 connected to the disk plate 4 eccentrically installed with respect to the rotation axis. It is preferable that the grizzly bar main body 1 is configured to reciprocate up and down once as the rotating shaft rotates once. In addition, since the adjacent Grizzly bar bodies 1 are installed so that the eccentric phases mentioned above are shifted by 180 degrees, the structure is such that the adjacent Grizzly bar bodies 1 repeatedly move up and down in opposite directions. preferable.

The wear-resistant sieve in which the grizzly bar main body 1 is installed in a swingable manner as described above is also referred to as a swinging roost. The abrasion resistant sieve 100 of the present invention can be preferably applied to such an oscillating rotor. This type of oscillating rotor can prevent, with even higher accuracy, the retention, accumulation, and adhesion of waste materials such as powder that should be sieved to the lower part of the wear-resistant sieve on the sieve surface. It is a wear-resistant sieve with high sorting ability that causes fewer problems such as clogging due to lumps, and can quickly remove large lumps remaining on the sieve surface, helping to improve the productivity of manufacturing plants equipped with this sieve. can contribute significantly.

For example, in the production process of zinc oxide ore by the Wertz method, when high-temperature discharge from a rotary kiln for dry heating containing a mixture of lumps, powders, and granules is sieved by the wear-resistant sieve 100, Among the high-temperature powder, granules, or lumps thrown onto the sieve surface of the wear-resistant sieve 100 constituted by a plurality of Grizzly bars 10, only the lumps of a certain size or more are removed by the Grizzly bars 10. It remains on top, rolls on the sieve surface arranged so as to form an inclined surface, and is discharged to a dedicated discharge port. Powder, granules, or lumps having a particle size below a certain level fall downward from the sieve surface and are conveyed to the next process by the conveyor 5. Incidentally, if the lumps of a certain size or more are not discharged, the conveyor 5 will be fatally damaged. Moreover, the chute for transferring from the conveyor 5 to another conveyor may be blocked. When these troubles occur, operations must be stopped and recovery measures taken over a long period of time.

Regarding the arrangement pitch of the grizzly bars 10 in the wear-resistant sieve 100, it is preferable that the width of the slits formed between the grizzly bars 10 is about 20 mm or more and about 60 mm or less. This is because if the slit width is less than 20 mm, clogging or blockage may occur, whereas if it exceeds 60 mm, lumps of 60 mm or more cannot be removed. For example, in the manufacturing process of zinc oxide ore by the Wertz method, when high-temperature discharge containing a mixture of lumps, powders, and granules from a rotary kiln for dry heating is sieved by the wear-resistant sieve 100. If so, it is essential to ensure at least this slit width of 20 mm or more.

<Grizzly bar>
As shown in FIGS. 3 to 5, the grizzly bar 10 constituting the abrasion resistant sieve 100 has a grizzly bar main body 1 made of a square prism-shaped metal rod, and a top side resistant plate that covers and joins the top and both side surfaces of the grizzly bar body 1. It includes a wear part 2 and a side wear-resistant part 3. These parts are integrated with each other by welding the wear-resistant materials 22 and 32 forming the top-side wear-resistant part 2 and the side-side wear-resistant part 3 to the Grizzly bar main body 1, thereby forming the Grizzly bar 10. It consists of

As the Grizzly bar main body 1, various metal members having both mechanical strength and heat resistance required depending on the usage environment can be appropriately selected and used. However, as long as these conditions can be satisfied, general structural steel materials such as SS400 and stainless steel materials such as SUS304, which are advantageous in terms of economy, can be preferably used.

As shown in FIG. 3, the top-side wear-resistant part 2 includes a top-side formwork 21 made of a plurality of metal plates erected on the top surface of the grizzly bar body 1, and a top-side formwork 21 within the top-side formwork 21. It consists of a wear-resistant material 22 that is cast. In this specification, "the top surface of the Grizzly bar main body" refers to the upper surface that is constantly hit by high-temperature burnt ore, etc. when the wear-resistant sieve 100 on which the Grizzly bar 10 is installed is used. Refers to one aspect that is assumed.

As shown in FIG. 3, the top-side wear-resistant portion 2 preferably has a gable roof shape whose cross section in front view is an isosceles triangle. In order to form the cross-sectional shape of the top side wear-resistant part 2 into the shape shown in FIG. and a metal plate cut into a right-angled triangular shape to form a formwork. By configuring the height of the plate to gradually increase from both sides of the top surface of the grizzly bar body 1 toward the center, it is possible to form the top surface wear-resistant portion 2 into a gable roof shape. can. Regarding the shape of the top side of the gable roof shape, an example of a preferable angle is that the apex angle of the gable roof, that is, the angle formed by both the above-mentioned slopes is, for example, 90°. .

As shown in FIG. 3, the side-side wear-resistant part 3 is a side-side type made of a plurality of metal plates erected on both sides of the Grizzly bar main body 1, that is, on two facing surfaces surrounding the top surface. It consists of a frame 31 and a wear-resistant material 32 cast into the side mold 31.

As shown in FIG. 4, the side formwork 31 constituting the side wear-resistant portion 3 preferably has a shape in which metal plates are arranged in a grid pattern. When the side wear-resistant part 3 is a grid-like formwork, the size of each grid is not particularly limited as long as the wear-resistant material 32 can be thermally sprayed; The size of each of the gratings is preferably about 30 mm or more and 60 mm or less in the direction and the lateral direction.

Both the top-side formwork 21 and the side-side formwork 31 can be constructed using general structural rolled steel material (SS material). The top-side formwork 21 and the side-side formwork 31 can be formed by welding plate materials made of the above-mentioned materials, which are preformed to an appropriate size, to each surface of the grizzly bar main body. Note that the formwork is necessary to make the thickness uniform and to arrange the finished shape in order to facilitate the casting work, so the welding of the plates does not have to be precise. Temporary fixing, so-called spot welding may be used.

As the wear-resistant materials 22 and 32 constituting the top-side wear-resistant portion 2 and the side-side wear-resistant portion 3, various conventionally known wear-resistant materials having heat resistance required depending on the usage environment may be used as appropriate. I can do it. Specifically, as the wear-resistant materials 22 and 32, general metal sprayed materials such as a tungsten carbide-containing self-fusing alloy, a nickel-based self-fusing alloy, a high chromium cast iron-based self-fusing alloy, etc. can be used as appropriate. Among them, high chromium cast iron-based wear-resistant materials, which have a well-balanced combination of heat resistance, abrasion resistance, and ease of availability including price due to being a general-purpose product, are used for the wear-resistant parts 2 on the top side and the wear-resistant side sides. It can be particularly preferably used as the wear-resistant materials 22 and 32 constituting the portion 3.

<Method for manufacturing Grizzly bars>
In the Grizzly bar 10 of the present invention described above, the wear-resistant materials 22 and 32 of both the top side wear-resistant part 2 and the side-side wear-resistant part 3 are directly joined to the surface of the Grizzly bar body 1. It is characterized in that a process of casting wear-resistant materials 22 and 32 by thermal spraying inside the top side formwork 21 and side side formwork 31 is carried out as an essential process so that the condition is maintained. It is preferable that these thermal sprayings be performed first on one side of each side, and finally on the top surface.

In this manufacturing method, instead of attaching a heat-resistant cover part to the Grizzly bar body 1 as in conventional products (see Fig. 6), the wear-resistant material is directly sprayed onto the Grizzly bar body 1. A sufficiently thick wear-resistant portion can also be formed on the side surface of the main body 1. Furthermore, by changing the height of the side formwork 31, the thickness of the wear-resistant layer can be optimized to a desired thickness depending on the usage environment.

In addition, in the wear-resistant sieve 100 using the Grizzly bar 10 of the present invention, when the wear of the wear-resistant materials 22 and 32 progresses to a predetermined degree or more after use for a certain period of time, the Grizzly bar 10 is replaced with a new one. On the other hand, by repeating the cycle of thermally spraying the wear-resistant materials 22, 32 on the removed old Grizzly bar 10 and reusing it, the Grizzly bar main body 1 can be repeatedly used for a long period of time.

<Zinc oxide ore manufacturing plant>
A zinc oxide ore manufacturing plant using the Wertz method involves a reduction roasting process in which zinc-containing ores such as iron and steel dust are reduced and roasted to obtain crude zinc oxide dust, and fluorine and cadmium are extracted from the crude zinc oxide dust obtained in the reduction roasting process. The entire process is carried out in which a wet process is performed to separate and remove zinc oxide to obtain a crude zinc oxide cake, and a drying and heating process is performed to dry and heat the crude zinc oxide cake obtained in the wet process to obtain zinc oxide burnt ore (sintered ore). It is an industrial plant. The present invention provides a reduction roasting rotary kiln (RRK) used in the reduction roasting process, a drying heating rotary kiln (DRK) used in the drying heating process, or In both of these rotary kilns, it can be preferably used as a fired product sorting device installed at the discharge end side of each rotary kiln.

[Reduction roasting process]
In the reduction roasting process, zinc-containing materials such as steel dust are subjected to reduction roasting using a reduction roasting rotary kiln (RRK). In this reduction roasting treatment, the maximum temperature of the object to be treated is controlled to be about 1100 to 1200°C. The RRK is equipped with an oil burner on the discharge end side from which the residue (clinker) is discharged, and is heated by direct flame from the discharge end side. In RRK, limestone is added as a calcium source to raise the melting point of the residue in the kiln and to prevent the buildup of residue inside the kiln. However, the use of carbonaceous materials such as coke, which can easily sustain a combustion state, and the reduced metal iron will quickly oxidize in the kiln if the carbon monoxide gas concentration decreases, causing heat generation due to the oxidation reaction. As a result, the residue particularly near the discharge end tends to reach a high temperature, and due to this, a lump is likely to be formed on the discharge end side of the furnace. Therefore, in many cases, a device called a coaching cutter is provided to prevent the excessive production of sludge and mechanically scrape off the slough during kiln operation. In this case, the RRK discharge may be contaminated with exfoliated lumps. In particular, in such RRKs, if lumps of a certain size or more are discharged and transported to the next process as they are, it may cause various malfunctions and production troubles. It is essential to provide a wear-resistant sieve on the end side. The wear-resistant sieve of the present invention can be particularly preferably used as the wear-resistant sieve installed in such a manner.

[Wet process]
In the wet process following the reduction roasting process, water-soluble impurities such as chlorine, fluorine, and cadmium contained in the crude zinc oxide dust obtained in the reduction roasting process are separated and extracted into the treatment liquid, and then solid-liquid separation treatment is performed. Accordingly, a wet process is performed in which impurities are removed from crude zinc oxide dust by a water washing method to obtain a crude zinc oxide cake.

[Drying and heating process]
In the drying and heating process, the crude zinc oxide cake obtained in the wet process is placed in a drying and heating rotary kiln (DRK) and fired to further reduce the halogen concentration and produce high-grade zinc oxide burnt ore. Perform dry processing. The crude zinc oxide cake charged into the DRK is granulated into pellets at the charging end inside the rotary kiln, then dried, heated, and baked at the discharge end. The DRK is equipped with an oil burner on the discharge end side from which zinc oxide ore is discharged, and is heated by direct flame from the discharge end side. The temperature of the burned ore of zinc oxide ore discharged from the rotary kiln is maintained and controlled to be within the range of 900°C or more and 1200°C or less. Similar to RRK, in DRK as well, the zinc oxide ore on the discharge end side near the burner flame tends to reach a high temperature, and slag is likely to form inside the kiln on the discharge end side. Therefore, in the DRK, the deposits attached to the inner wall may peel off and be discharged from the discharge end of the kiln as a large lump. Furthermore, when zinc oxide ores exist that have an extremely long residence time and the zinc oxide ores fuse together, large lumps may be formed and discharged from the discharge end of the kiln. If lumps larger than a certain size are discharged and sent directly to the next process, it can cause various malfunctions and production problems, so the system is equipped with a sorting function to sort and separate them. It is necessary to install a wear-resistant sieve. As the wear-resistant sieve installed in such a manner, the wear-resistant sieve of the present invention can be particularly preferably used.

Grizzly bars of Examples were manufactured using the following materials and according to the manufacturing method described below, and their effects were verified through test operations.

Grizzly bar body: Stainless steel (SUS304) bar, width 90mm, height 225mm, length 1,190mm.
Top side formwork: Uses general structural rolled steel plate material (SS material). The metal plate erected through the center of the top surface of the Grizzly bar body 1 has a thickness of 9 mm and a width of 64.5 m. For triangular partition plates, the thickness is 6 mm.
Side formwork: Uses general structural rolled steel plate material (SS material). The metal plate erected parallel to the long side of the Grizzly bar body 1 has a thickness of 9 mm and a width of 24.5 mm. The thickness of the partition plate that divides each cell is 6 mm.
Wear-resistant material: High-chromium cast iron-based high-temperature wear-resistant material (``UF-0'' (manufactured by ING Shoji Co., Ltd.)) is used. The components are C: 5.5%, Cr: 22%, Nb: 7%, W: 2%, V: 1%. The hardness is 950 to 1050 on Vickers hardness (HV).

First, a lattice-like formwork consisting of 80 cells on each side was created on both sides of the Grizzly bar main body using the plate material for the side formwork as shown in FIG. The plates used to form the formwork were joined by welding. The size of each grid was 53 mm x 36.7 mm. Then, the above-mentioned wear-resistant material is thermally sprayed into the side-side formwork and welded to the side-side wear-resistant parts so that it is directly bonded to the surface of each side of the Grizzly bar body. was formed.

Next, use the plate material for the top side formwork on the top of the Grizzly bar body, arrange as shown in Figures 3 and 5, and make the outer shape of the top side wear-resistant part into a gable roof shape. In order to be able to form a mold, a total of 40 molds, 20 molds each having a triangular shape when viewed from the front, were created on the left and right sides of a board erected at the center. The plates were joined by welding. The height of the board erected at the center was 64.5 mm, and the size of the bottom of each mold was 53 mm x 65 mm. Then, the above-mentioned wear-resistant material is thermally sprayed into the top-side formwork and welded so that it is directly bonded to the top-side surface of the Grizzly bar body. A worn part was formed.

The Grizzly bar manufactured as described above was attached to a wear-resistant sieve installed at the discharge end of a dry heating rotary kiln (DRK) of a manufacturing plant that manufactures zinc oxide burnt ore using the Wertz process, and test operations were conducted for six months. I went between. Before the start of this test operation, a grizzly bar was installed in which a wear-resistant protective cover of the conventional structure shown in FIG. 6 was attached to the grizzly bar body by bolts via connecting hardware. In this conventional wear-resistant protective cover, a high-chromium cast iron-based wear-resistant material similar to the wear-resistant material of the above embodiment was used as the wear-resistant material.

For wear-resistant sieves equipped with conventional grizzly bars, due to wear on the wear-resistant protective cover and the sides of the grizzly bar body, it is necessary to remove the grizzly bar body once every month or so and replace only the wear-resistant protective cover. Alternatively, it was necessary to replace the entire Grizzly bar body with the wear-resistant protective cover attached. On the other hand, after installing the grizzly bar of the example, it became possible to use it for three months. In addition, at intervals of about 3 months, the wear-resistant parts that have progressed to wear are re-sprayed with wear-resistant material to re-form the wear-resistant parts, thereby preventing the wear of the Grizzly bar body and allowing it to be reused for a long period of time. It became possible to use it. The production cost of the Grizzly bar itself has increased by about 1.4 times due to the increase in the amount of wear-resistant material used, but the life of the Grizzly bar itself has tripled, and the main body can be reused over a long period of time. It has been confirmed that there is a sufficient economic advantage.

In addition, by integrating the wear-resistant part into the Grizzly bar body, not only is it freed from complicated replacement work, but it also eliminates the risk of the protective cover falling off due to abrasion of the tips of the mounting bolts during use in a high-temperature atmosphere. This made it possible to avoid sudden shutdowns and the risk of damage to the conveyor due to large lumps or falling protective covers. In the past, it was thought that the work of replacing only the cover parts was more efficient. However, due to use in a high-temperature atmosphere, the bolts and nuts for mounting the cover parts were welded together, and it took a lot of effort to remove them, so it was easier and economically advantageous to replace the Grizzly Bar 10 itself. It was also found that

1 Grizzly bar body 10 Grizzly bar 2 Top side wear-resistant part 21 Top side formwork 22 Wear-resistant material 3 Side-side wear-resistant part 31 Side-side formwork 32 Wear-resistant material 4 Disc plate 5 Conveyor 6 Connection hardware 7 Bolts 100 Abrasion sieve 10B Grizzly bar (conventional product)

Claims (8)

A grizzly bar for wear-resistant sieves,
A grizzly bar body consisting of a square prism-shaped metal rod,
a top-side wear-resistant part installed on the top surface, which is one surface in the longitudinal direction of the metal rod;
side wear-resistant parts installed on both side surfaces in contact with the longitudinal direction of the top surface,
The top-side wear-resistant part includes a top-side formwork made of a plurality of metal plates erected on the top surface of the Grizzly bar body, and a top-side formwork formed by casting into the top-side formwork to form the Grizzly bar body. It consists of a wear-resistant material welded to the
The side-side wear-resistant part includes a side-side formwork made of a plurality of metal plates erected on the side surface of the Grizzly bar body, and is cast into the side-side formwork and welded to the Grizzly bar body. consisting of wear-resistant material,
grizzly bar. The side formwork is formed by arranging the metal plates in a grid pattern.
Grizzly bar according to claim 1. The outer shape of the top side wear-resistant part is formed in the shape of a gable roof.
Grizzly bar according to claim 1 or 2. The wear-resistant material is a high-chromium cast iron-based wear-resistant material,
The grizzly bar according to any one of claims 1 to 3. An abrasion-resistant sieve comprising the Grizzly bar according to any one of claims 1 to 4. A fired product sorting facility comprising: an industrial furnace for discharging fired products fired to a temperature of 700° C. or higher; and a wear-resistant sieve according to claim 5 installed on the discharge end side of the industrial furnace. A plant for producing zinc oxide ore by the Wertz process, wherein the wear-resistant sieve according to claim 5 is installed on the discharge end side of a rotary kiln for a reduction roasting process and/or a rotary kiln for a drying and heating process. , zinc oxide ore production plant. A method for producing a grizzly bar according to any one of claims 1 to 4,
In both the top-side wear-resistant part and the side-side wear-resistant part, the wear-resistant material is bonded directly to the surface of the grizzly bar main body. performing a step of casting the wear-resistant material into the side formwork by thermal spraying;
How to make grizzly bars.

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