JP7800487B2 - Belt conveyor chute device - Google Patents

Description

The present invention relates to a belt conveyor chute device for transporting granular material from a belt conveyor to a vibrating screen.

Raw materials handled at steel mills include granular materials such as ore, coal, sintered ore, and coke. The granular materials are sieved into appropriate particle sizes using vibrating screens and then used in various steelmaking processes.

The granular material is transported by a belt conveyor and supplied to the vibrating screen via a belt conveyor chute. If the granular material is unevenly deposited on the vibrating screen, the vibrating screen's capabilities may not be fully utilized, and proper sieving may not be possible. For this reason, it is preferable that the granular material be deposited on the vibrating screen at as even a thickness as possible.

The width of the belt conveyor chute is made equal to the width of the belt conveyor. In many cases, the widths of the belt conveyor and the vibrating screen are significantly different, with the width of the belt conveyor being narrower than the width of the vibrating screen. This creates the problem of particulate matter being unevenly deposited in the center of the vibrating screen's width.

Conventionally, when transporting granular materials on a belt conveyor, attempts have been made to supply the granular materials uniformly across the width of the conveyance. For example, in Patent Document 1, an obstacle member is provided in a chute that transfers granular materials from an upstream belt conveyor to a downstream belt conveyor to disperse the granular materials and transport them to the downstream conveyor.

Japanese Patent Application Laid-Open No. 2004-175479

In the belt conveyor chute of Patent Document 1, the supply port through which granular material is supplied to the chute and the discharge port through which the granular material is discharged are arranged vertically. Therefore, when the belt conveyor chute of Patent Document 1 is used to connect a belt conveyor to a vibrating screen, the granular material flows down at a high speed, which makes it difficult to uniformly disperse the granular material across the width of the vibrating screen.

The present invention was made in consideration of the above-mentioned problems, and aims to provide a belt conveyor chute device that can reduce the bias of granular material across the width of the vibrating screen.

To solve the above problems, the present invention has the following features:

[1]
A belt conveyor chute device for conveying granular material from a belt conveyor to a vibrating screen, comprising:
a box having a supply port through which the granular material is supplied from the belt conveyor and a discharge port through which the granular material is discharged toward the vibrating screen,
The box body has a step portion formed in a stepped shape between the supply port and the discharge port;
a first distributor that is provided closer to the discharge port than the step and that regulates the direction of movement of the granular material;
a second distributor that is provided closer to the discharge outlet than the first distributor and that regulates the direction of movement of the granular material.
[2]
The belt conveyor chute device according to [1], wherein the first distribution section is located on an extension of the ridge line of the granular material when the granular material accumulated in the step section forms an angle of repose.
[3]
The belt conveyor chute device described in [1] or [2], wherein the second distribution section is located on an extension of the ridge line of the granular material when the granular material accumulated in the first distribution section forms an angle of repose.
[4]
The second distribution portion is formed in a plate shape extending in a direction along the width direction of the discharge port,
The belt conveyor chute device according to any one of [1] to [3], wherein the length of the second distribution section in the width direction of the discharge outlet is 60 to 95% of the width of the discharge outlet.
[5]
the step portion is provided on a wall portion of the box body opposite to a wall portion to which the belt conveyor is connected to the supply port,
the first distribution section and the second distribution section are provided on the same wall section as the wall section on which the step section is provided,
The belt conveyor chute device according to any one of [1] to [4], wherein the discharge outlet is provided in a wall portion opposite to the wall portion on which the second distribution portion is provided.

With the belt conveyor chute device of the present invention, granular material supplied from the supply port is deposited in the step section. The granular material then flows downward along the granular material deposit formed in the step section and is deposited in the first distribution section. The granular material then flows downward along the granular material deposit formed in the first distribution section and is deposited in the second distribution section. The granular material then flows downward along the granular material deposit formed in the second distribution section and is discharged from the discharge port.

The granular material flows down along the deposits formed in the step section, first distribution section, and second distribution section, slowing its flow speed. Therefore, the granular material can be distributed efficiently in the first distribution section and second distribution section, reducing the uneven distribution of the granular material across the width of the vibrating screen.

FIG. 2 is a perspective view of the belt conveyor chute device. FIG. 2 is an explanatory diagram showing the internal structure of the box shown in FIG. 1 . FIG. 2 is a cross-sectional view of the upper side of the box of FIG. 1 . FIG. 2 is a cross-sectional view of the lower side of the box body of FIG. 1 . FIG. 10 is an explanatory diagram showing the flow of granular material supplied to the box. FIG. 10 is an explanatory diagram showing the internal structure of a box according to a second embodiment. 10 is an explanatory diagram showing the internal structure of a box according to a modified example of the second embodiment. FIG. 1 is a graph showing a quantitative analysis of particulate matter in the width direction of a vibrating screen.

(First embodiment)
An embodiment of the present invention will now be described with reference to the drawings. Fig. 1 is a perspective view of a belt conveyor chute device 100. As shown in Fig. 1, the belt conveyor chute device 100 has a box-shaped box body 10. A belt conveyor 20 for transporting granular material and a vibrating screen 30 for classifying the granular material into desired particle sizes are connected to the box body 10.

The belt conveyor 20 has a circular belt 22 stretched across a pair of pulleys 21 located at one end and the other end in the conveying direction. Therefore, when the pulleys 21 are operated, the belt 22 moves in the conveying direction.

The granular materials transported from the belt conveyor 20 are not particularly limited, but examples include ore, coal, sintered ore, coke, silica, and pellets (ore made by adding water and a binder to form a spherical shape and then baking it).

The vibrating screen 30 is a sieving device that classifies granular material by vibrating a first sieve 31 and a second sieve (not shown) that is positioned below the first sieve and has finer mesh than the first sieve. The granular material discharged from the belt conveyor chute device 100 is classified by the vibrating screen 30.

The box body 10 has a rectangular parallelepiped shape at the top and a truncated cone shape at the bottom. The box body 10 has a space surrounded by an inner wall. A supply port 11 is formed at the top of the box body 10, through which granular material is supplied from the belt conveyor 20.

In this embodiment, the supply port 11 is provided in the wall 13 of the box body 10. Furthermore, in this embodiment, the pulley 21 of the belt conveyor 20 passes through the supply port 11. Therefore, the granular material transported from the belt conveyor 20 is supplied from the supply port 11 into the interior of the box body 10.

A discharge port 12 is formed at the bottom of the box body 10, through which the supplied granular material is discharged toward the vibrating screen 30. In this embodiment, the discharge port 12 is provided in the wall portion 13 of the box body 10. That is, the supply port 11 and the discharge port 12 are formed in the wall portion 13 to which the belt conveyor 20 is connected.

A stepped portion 14 is provided between the supply port 11 and the discharge port 12 of the box body 10. The position of the stepped portion 14 is not particularly limited, but in this embodiment, it is provided on the wall portion 15 opposite the wall portion 13 to which the belt conveyor 20 is connected to the supply port 11. Granular material supplied from the belt conveyor 20 is deposited on the stepped portion 14.

Figure 2 shows the internal structure of the box 10 of Figure 1. As shown in Figure 2, the wall portion 15a extending downward from the step portion 14 is formed at an acute angle with respect to the step portion 14. In this embodiment, the wall portion 15a is formed so as to form an L-shape with respect to the step portion 14 in a side view. The wall portion 15 has a wall portion 15b extending downward from the wall portion 15a. The wall portion 15b is formed so as to form an obtuse angle with respect to the wall portion 15a. The width of the wall portion 15b increases as it extends downward.

The box 10 has a first distribution section 16 that is located closer to the outlet 12 than the step section 14. More specifically, the first distribution section 16 is located on the wall section 15a that continues downward from the step section 14.

The first distribution section 16 is formed in a plate shape extending along the width direction of the discharge port 12. In this embodiment, the first distribution section 16 is attached perpendicular to the wall surface of the wall section 15a. The first distribution section 16 may be detachably attached to the wall section 15a using, for example, fastening means such as bolts (not shown).

The box 10 has a second distribution section 17 that is located closer to the outlet 12 than the first distribution section 16. More specifically, the second distribution section 17 is located on the wall section 15b that continues downward from the wall section 15a.

The second distribution section 17 is formed in the shape of a plate extending along the width direction of the discharge outlet 12. The length of the second distribution section 17 along the width direction of the discharge outlet 12 should be 60 to 95% of the width of the discharge outlet 12. By making it 60% or more of the width of the discharge outlet 12, the direction of movement of the granular material can be efficiently restricted. Furthermore, by making it 95% or less of the width of the discharge outlet 12, the movement of the granular material can be efficiently achieved.

In this embodiment, the second distribution unit 17 is attached perpendicular to the wall surface of the wall portion 15b. The second distribution unit 17 may be detachably attached to the wall portion 15b using, for example, fastening means such as bolts (not shown).

Figure 3 shows a cross section of the upper side of the box body 10. As shown in Figure 3, when granular material 40 is supplied to the box body 10 from the belt conveyor 20, the granular material 40 is deposited in the step portion 14. When the granular material 40 is deposited in the step portion 14, a deposit having an angle of repose θ1 is formed.

The angle of repose θ1 of the granular material 40 varies depending on the type of granular material 40. For example, if the granular material 40 is sintered ore, the angle of repose θ1 is 30 to 50 degrees. If the granular material 40 is silica, the angle of repose θ1 is 20 to 25 degrees.

The first distribution section 16 is located on an extension of the ridge line L1 of the granular material 40 (sediment) accumulated in the step section 14. Newly supplied granular material 40 flows down along the ridge line L1 of the granular material 40 (sediment) accumulated in the step section 14. The granular material 40 that flows down along the ridge line L1 accumulates in the first distribution section 16. When the granular material 40 accumulates in the first distribution section 16, it forms an angle of repose θ1.

In this way, the first distribution section 16 is located on an extension of the ridge line L1 of the granular material 40 (deposit) when the granular material 40 deposited on the step section 14 forms an angle of repose θ1. In this embodiment, the end of the first distribution section 16 is located on an extension of the ridge line L1 of the granular material 40 (deposit).

The first distributor 16 is preferably provided so that its height and widthwise position on the box 10 can be adjusted so that it is positioned on an extension of the ridge line L1 of the granular material 40 (deposit) when the granular material 40 deposited on the step portion 14 forms an angle of repose θ1. For example, the first distributor 16 is preferably provided so that its fixed position can be changed using a bolt.

Figure 4 shows a cross section of the lower side of the box body 10. As shown in Figure 4, granular material 40 is deposited in the step portion 14, forming a deposit having an angle of repose θ1. Similarly, granular material 40 is deposited in the first distribution portion 16, forming a deposit having an angle of repose θ1.

The newly supplied granular material 40 flows down along the ridge line L2 of the granular material 40 (deposit) deposited in the first distribution section 16. The granular material 40 that flows down along the ridge line L2 deposits in the second distribution section 17. When the granular material 40 deposits in the second distribution section 17, a deposit having an angle of repose θ1 is formed.

In this way, the second distribution section 17 is located on an extension of the ridge line L2 of the granular material 40 (deposit) when the granular material 40 deposited in the first distribution section 16 forms an angle of repose. In this embodiment, the end of the second distribution section 17 is located on an extension of the ridge line L2 of the granular material 40 (deposit).

The second distribution section 17 is preferably provided so that its height position and widthwise position in the box 10 can be adjusted so that it is positioned on an extension of the ridge line L2 of the granular material 40 (deposit) when the granular material 40 deposited in the first distribution section 16 forms an angle of repose θ1. For example, the second distribution section 17 is preferably provided so that its fixing position with a bolt can be changed.

Figure 5 shows the flow of granular material 40 supplied to the box 10. As shown in Figure 5, granular material 40 supplied from the supply port 11 is deposited in the stepped portion 14, first distribution portion 16, and second distribution portion 17. Newly supplied granular material 40 flows down along the ridge lines L1 and L2 of the granular material 40 (deposit) deposited in the stepped portion 14, first distribution portion 16, and second distribution portion 17. In other words, the newly supplied granular material 40 is discharged from the discharge port 12 with its direction of movement restricted by the granular material 40 deposited in the stepped portion 14, first distribution portion 16, and second distribution portion 17.

The granular material 40 flows down along the deposits formed in the step portion 14, first distribution portion 16, and second distribution portion 17, and therefore its flow speed decreases. In particular, because the step portion 14 is provided on the wall portion 15 opposite the wall portion 13 in which the supply port 11 is formed, the flow speed of the granular material 40 can be reduced by the step portion 14 or the deposit of granular material 40 accumulated in the step portion 14.

Furthermore, by providing the first distribution section 16 on the same wall section 15 as the step section 14, the flow-down speed of the granular material 40 can be reduced by the first distribution section 16 or by the accumulation of granular material 40 accumulated on the first distribution section 16. Similarly, by providing the second distribution section 17 on the same wall section 15 as the step section 14, the flow-down speed of the granular material 40 can be reduced.

Furthermore, since the discharge outlet 12 is provided on the wall 13 opposite the wall 15 on which the second distribution section 17 is provided, the granular material 40, whose flow rate has been sufficiently reduced, can be discharged from the discharge outlet 12 in a state where it is dispersed in the width direction of the vibrating screen 30.

In this way, with the belt conveyor chute device 100 of this embodiment, the granular material 40 is distributed by the first distribution section 16 and the second distribution section 17, making it possible to reduce the uneven distribution of the granular material 40 across the width of the vibrating screen 30.

Second Embodiment
In the above embodiment, the second distribution section 17 is formed as a single plate. However, a plurality of second distribution sections 17 may be formed. Note that the same members as those in the first embodiment are denoted by the same reference numerals and descriptions thereof will be omitted.

Figure 6 is an explanatory diagram showing the internal structure of the box 10 according to the second embodiment. As shown in Figure 6, the second distribution section 18 is composed of two upper sections 18a arranged in the width direction of the wall section 15b, and a lower section 18b located below the upper sections 18a.

The two upper tiers 18a are spaced apart in the width direction of the wall portion 15b. In the example shown in Figure 6, the lower tier 18b is located between the two upper tiers 18a. Therefore, granular material 40 that flows down from between the two upper tiers 18a is deposited in the lower tier 18b. It is preferable that the lower tier 18b be adjustable in height and width direction relative to the box 10 so that it is positioned on an extension of the ridge line L2 of the granular material 40 (deposit) when the granular material 40 deposited on the upper tier 18a forms an angle of repose θ1.

Even when the second distribution section 18 is configured in this manner, the granular material 40 is distributed by the first distribution section 16 and the second distribution section 17, just as in the belt conveyor chute device 100 of the first embodiment. This makes it possible to reduce the uneven distribution of the granular material 40 across the width of the vibrating screen 30.

The second distribution section 18 is not limited to this configuration and may, for example, be configured with multiple lower tiers 18b. Figure 7 is an explanatory diagram showing the internal structure of the box 10 according to a modified example of the second embodiment. As shown in Figure 7, the lower tier 18b is provided outside the two upper tiers 18a in the width direction of the wall 15. Therefore, granular material 40 that flows down from the outside of the two upper tiers 18a is deposited in the lower tier 18b. Even when the second distribution section 18 is configured in this manner, the same effects as those of the above-described embodiment can be obtained. Furthermore, the second distribution section 18 is not limited to being configured with two tiers, the upper tier 18a and the lower tier 18b, and may be configured with three or more tiers.

The belt conveyor chute device shown in Figures 2, 6, and 7 was used to evaluate the dispersion of granular material on a vibrating screen. Quantitative analysis was performed using the Distinct Element Method (DEM) to evaluate the dispersion of the granular material. The quantitative analysis took into consideration the specifications of the belt conveyor and the physical properties of the raw material being transported.

The analysis results are shown in Figure 8. In Figure 8, the belt conveyor chute device in Figure 7 is designated as Example 1, the belt conveyor chute device in Figure 6 is designated as Example 2, and the belt conveyor chute device in Figure 2 is designated as Example 3.

For Examples 1 to 3, the length of the first distribution section along the width of the discharge outlet was determined based on the angle of repose of the granular material and the expected thickness (layer thickness) of the granular material deposit. Specifically, the angle of repose of the granular material was set to 36°. The length of the first distribution section along the width of the discharge outlet was set to 400 mm.

The height from the first distribution section to the step section was set to 290 mm. This was calculated based on the length of the first distribution section along the width direction of the outlet (400 mm) x tan (angle of repose: 36°).

In Example 1 shown in Figure 7, the location of the upper section of the second distribution section was determined based on the angle of repose of the granular material accumulated in the first distribution section. The location of the lower section of the second distribution section was determined based on the angle of repose of the granular material accumulated in the upper section of the second distribution section.

In Example 2 of the invention shown in Figure 6, the placement of the upper section of the second distribution section was determined in the same way as in Example 1. The placement of the lower section of the second distribution section was determined so that it was located in the center of the outlet in the width direction.

In Example 3 of the invention shown in Figure 2, the arrangement of the upper section of the second distribution section was determined in the same way as in Example 1. However, in Example 3 of the invention, a single plate-shaped second distribution section was used to connect the upper sections of the two second distribution sections of Example 1.

Boxes for measuring the amount of granular material were arranged across the width of the vibrating screen, and the mass percentage of granular material flowing into each box was measured. The results are shown in Figure 8. The box located at one end of the vibrating screen's width was designated No. 1, the box located at the other end was designated No. 20, and boxes No. 2 to No. 19 were placed at specified intervals between No. 1 and No. 20. In Figure 8, the box numbers are shown on the horizontal axis, and the mass percentage of granular material is shown on the vertical axis.

The gray area in Figure 8 indicates the range of the box into which granular material flows when using a conventional belt conveyor chute device that does not have a first distribution section or a second distribution section. In other words, in the conventional example, most of the granular material is concentrated in the central area on the vibrating screen.

The belt conveyor chute devices of Invention Examples 1 to 3 are able to supply granular material more uniformly across the width of the vibrating screen than conventional examples. In Invention Example 1, it can be seen that the granular material is concentrated in the center of the vibrating screen. In Invention Example 2, the dispersion of the granular material was improved compared to Invention Example 1, but the amount supplied to the center of the vibrating screen was reduced. Invention Example 3 was found to have the best dispersion of granular material compared to Invention Examples 1 and 2. This was confirmed by forming the upper section of the second distribution section into a plate-like shape, which dispersed the granular material flowing downstream of the upper section of the second distribution section. In this way, by arranging the first distribution section and second distribution section as in Invention Example 3, it is possible to supply the amount of granular material across the width of the vibrating screen more uniformly than Invention Examples 1 and 2.

100 Belt conveyor chute device 10 Box body 11 Supply port 12 Discharge port 13 Wall portion 14 Step portion 15 Wall portion 16 First distribution portion 17 Second distribution portion 18 Second distribution portion

Claims (5)

A belt conveyor chute device for conveying granular material from a belt conveyor to a vibrating screen, comprising:
a box having a supply port through which the granular material is supplied from the belt conveyor and a discharge port through which the granular material is discharged toward the vibrating screen,
The box body has a step portion formed in a stepped shape between the supply port and the discharge port;
a first distributor that is provided closer to the discharge port than the step and that regulates the direction of movement of the granular material;
a second distributor that is provided closer to the discharge port than the first distributor and that regulates the direction of movement of the granular material ;
The second distribution portion is formed in a plate shape extending in a direction along the width direction of the discharge port,
A belt conveyor chute device , wherein the length of the second distribution section in the width direction of the discharge outlet is 60 to 95% of the width of the discharge outlet . The belt conveyor chute device according to claim 1, wherein the first distribution section is located on an extension of the ridge line of the granular material accumulated in the step section when the granular material forms an angle of repose. The belt conveyor chute device according to claim 1 or 2, wherein the second distribution section is located on an extension of the ridge line of the granular material accumulated in the first distribution section when the granular material forms an angle of repose. the step portion is provided on a wall portion of the box body opposite to a wall portion to which the belt conveyor is connected to the supply port,
the first distribution section and the second distribution section are provided on the same wall section as the wall section on which the step section is provided,
The belt conveyor chute device according to claim 1 or 2, wherein the discharge port is provided in a wall portion opposite to the wall portion on which the second distributor is provided. the step portion is provided on a wall portion of the box body opposite to a wall portion to which the belt conveyor is connected to the supply port,
the first distribution section and the second distribution section are provided on the same wall section as the wall section on which the step section is provided,
The belt conveyor chute device according to claim 3 , wherein the discharge port is provided in a wall portion opposite to the wall portion on which the second distributor is provided.