JP2016013881A - Damper shaft used in surge hopper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a damper shaft of a damper that is used in a surge hopper which temporarily stores a sintered ore from a rotary kiln in ferronickel smelting, which can be used effectively as the damper shaft allowing a damper main body to be preferably opened and closed, is prevented from being deformed and broken by heat received from the sintered ore and has excellent workability in maintenance or the like.SOLUTION: A damper shaft 11 is made from a columnar steel material 21, and inside the columnar steel material 21 is provided a columnar water passage 22 which is continuous across a long shaft direction of the steel material 21, whose center axis is identical to the center axis of the steel material 21. In the damper shaft 11, when a diameter of the steel material 21 is set as D1 and a diameter (an Inner diameter) of a circular cross section of the water passage 22 is set as D2, a relation of 0.2×D1≤D2≤0.55×D1 is satisfied.

Description

  The present invention relates to a damper shaft, and more particularly, a surge hopper damper component for temporarily storing calcined ore obtained from a rotary kiln used in ferronickel smelting, which opens and closes when the damper is opened and closed. It is related to the damper shaft which becomes the axis of

  In ferronickel smelting, nickel oxide ore with a nickel quality of about 2% by weight (hereinafter simply referred to as “ore”) is used as a raw material, through steps such as preliminary drying, drying and partial reduction, reduction melting, desulfurization, casting, Produces ferronickel with a nickel grade of about 20% by weight.

  In the smelting of ferronickel, in the reduction melting process of reducing and melting the ore obtained after being subjected to partial reduction treatment, the ore is melted using an electric furnace or the like that is a reduction furnace. However, if the ore contains crystal water, it will cause a steam explosion in the electric furnace.

  From this, in the drying and partial reduction process, which is the process prior to the reduction and melting process, using a rotary kiln or the like, the crystallization temperature in the ore is decomposed and removed by setting the ore temperature to, for example, 800 ° C. or higher. ing. From the rotary kiln, ore from which crystal water of about 800 ° C. or higher is removed (hereinafter referred to as “calcined ore”) is obtained.

  Here, with reference to FIG. 1 specifically, the flow until the burned ore obtained in the rotary kiln is charged into the electric furnace will be described.

  As shown in FIG. 1, the burned ore obtained by the rotary kiln 2 is temporarily stored in the surge hopper 1. Although the details of the mine stored in the surge hopper 1 will be described later, the hopper (hereinafter referred to as the hopper) provided after the surge hopper 1 is opened by opening a damper of the surge hopper 1 provided at the lower end of the surge hopper 1. The damper provided in the surge hopper 1 is closed when the sinter charged into the slag hopper reaches a predetermined weight. Then, the damper of the sinter hopper is opened, and the sinter of a predetermined weight stored in the sinter hopper is charged into the sinter container 3.

  After the mine container 3 is transported to a position where a crane (hereinafter referred to as “furnace crane”) 5 stands by using a transport carriage 4, the mine container 3 is lifted by the furnace crane 5, and the upper part of the electric furnace 7. Is loaded into a hopper 6 (hereinafter referred to as “baking mine”) provided in the factory. Then, the sinter charged in the sinter bin 6 is charged into the electric furnace 7.

  As described above, when transferring the sinter from the rotary kiln 2 to the electric furnace 7, the damper used in the surge hopper 1 plays an important role in the discharge control of the sinter with the surge hopper 1. Yes. As will be described in detail later, as shown in FIGS. 2 and 3, the damper 10 used in the surge hopper 1 has a flapper structure, and moves a cylinder 12 installed outside the surge hopper 1. Thus, the damper 10 is opened and closed by rotating around the damper shaft 11.

  The damper 10 of the surge hopper 1 is loaded with a maximum of several tons of mine when the damper 10 is closed. Therefore, the damper 10 needs to be able to withstand the weight of the sinter.

  Moreover, the damper 10 of the surge hopper 1 and the damper shaft 11 which is a component of the damper 10 must have a structure capable of withstanding the heat of calcination at 800 ° C., for example. For example, if the damper shaft 11 does not have a structure capable of withstanding the heat of high-temperature sinter, the damper shaft 11 is deformed by the heat of the sinter. As a problem when the damper shaft is deformed, the damper shaft 11 is displaced, so that it is sometimes called a castable refractory (unshaped refractory) provided around the damper 10 as shown in FIG. (Hereinafter, simply referred to as “caster”) 14, the opening / closing trouble such that the damper 10 cannot be opened / closed, half-opened or half-closed occurs. Further, when the damper shaft 11 comes into contact with the casters 14, the casters 14 are dropped, and the slag hopper 8 is directly exposed to high-temperature slag, thereby causing deformation or breakage of the sinter hopper 8. Sometimes.

  As another problem, as shown in FIG. 4, a load is applied to the ground packing 16 and the ground retainer 17 of the ground box 15 due to the deformation of the damper shaft 11, and the ground packing 16 and the ground retainer 17 are damaged. Become. If the gland packing 16 or the gland retainer 17 is broken, the rotation of the damper shaft 11 is hindered to cause an abnormal opening / closing of the damper 10, and trouble such as high temperature gas or dust inside the surge hopper 1 is ejected from the broken gland packing 16. Wake up.

  In order to prevent the deformation of the damper shaft 11 due to the heat of such high-temperature sinter, it is conceivable to cool the damper shaft 11 using cooling water, for example. However, if the cooling water leaks into the calcination hopper 8, there is a risk that moisture enters the calcination and causes a steam explosion in the electric furnace 7 at the charging destination. Therefore, even if the damper shaft 11 is damaged, it is necessary to have a structure in which the cooling water does not leak into the sinter hopper 8.

  For this reason, there is no deformation or breakage due to the heat received from the sinter for the damper shaft, which is a component of the damper used in the surge hopper in which the smelter is temporarily stored by ferronickel smelting, and maintenance. Those having good workability such as the above are demanded.

  For example, Patent Document 1 discloses a technique related to an in-furnace carrier roll provided inside a resin drying furnace or the like that dries a resin applied to the surface of a steel sheet. A technology is disclosed for a roll for moving a slab, a water passage is formed in the central portion of the shaft, the outer cylinder is rotatable, and the steel plate is not damaged. However, this technique cannot be directly applied to a damper shaft, which is a component of a surge hopper damper that temporarily stores sinter obtained from a rotary kiln used in ferronickel smelting. In addition, the water-cooled shaft described in Patent Document 1 describes an application temperature that “can be widely applied to a low-speed conveyance type heating furnace of 600 ° C. or less”, and in ferronickel smelting that has a temperature exceeding 600 ° C. It cannot withstand calcination.

JP 2005-053612 A

  The present invention has been proposed in view of such a situation, and in ferronickel smelting, a damper main body is provided for a damper shaft of a damper used in a surge hopper that temporarily stores sinter from a rotary kiln. An object of the present invention is to provide a damper shaft that can be opened and closed well and can be used effectively as a damper shaft, has no deformation or breakage due to heat received from the sinter, and has good workability such as maintenance.

  The inventors of the present invention have made extensive studies in order to solve the above-described problems. As a result, the damper shaft is made of a cylindrical steel material, and a cylindrical water passage is continuously provided in the steel material over the major axis direction. The diameter of the circular cross section of the steel material and the circular cross section of the water passage The present invention has been completed by finding that it is a damper shaft that can be used effectively as a damper shaft by being configured so as to satisfy a predetermined relationship with the diameter, and is free from deformation and breakage.

  (1) The present invention is a damper shaft for opening and closing a damper used in a surge hopper for storing burned ore in ferronickel smelting, which is made of a columnar steel material, and the inside of the columnar steel material Is provided with a cylindrical water passage having the same central axis as that of the steel material, the diameter of the steel material being D1, and the diameter of the circular cross section of the water passage. Is a damper shaft characterized by satisfying the relationship of “0.2 × D1 ≦ D2 ≦ 0.55 × D1”.

  (2) Moreover, this invention is a damper axis | shaft which is more than the width | variety of the attachment position of the said damper in the said surge hopper in the invention which concerns on (1).

  (3) Moreover, this invention is a damper axis | shaft by which the internal thread which the cooling water supply piping is connected to the both ends of the said water flow path in the invention which concerns on (1) or (2) is cut.

  (4) The present invention is the damper shaft according to any one of (1) to (3), wherein a steel type of the steel material is SUS310S.

  (5) Moreover, this invention is a damper axis | shaft whose diameter D1 of the said steel materials is 100 mm or more and 150 mm or less in any invention of (1) thru | or (4).

  (6) Further, in the invention according to any one of (1) to (5), the surge hopper may have a weight of 1 t or more and 4 t or less of a combined weight of the sinter stacked on the damper and the weight of the damper. This is a damper shaft configured to have a size.

  According to the present invention, there is provided a damper shaft that can be used effectively as a damper shaft for opening and closing the damper satisfactorily, has no deformation or breakage due to heat received from the mine, and has good workability such as maintenance. be able to.

It is a figure for demonstrating the flow until the calcined ore obtained with the rotary kiln is inserted into an electric furnace. It is a schematic sectional drawing of the sinter hopper and the sinter hopper provided in the lower end of the surge hopper. It is the schematic sectional drawing which expanded the location of the damper in a surge hopper. It is the schematic which shows the ground part of a damper axis | shaft. It is a schematic diagram for demonstrating the structure of a damper shaft. It is a schematic diagram which shows the structure (another structure) of a damper shaft.

Hereinafter, specific embodiments of the present invention (hereinafter referred to as “present embodiments”) will be described in detail in the following order with reference to the drawings. In addition, this invention is not limited to the following embodiment, A various change is possible in the range which does not change the summary of this invention.
1. 1. Outline of surge hopper configuration and slag discharge processing in surge hopper 2. About the damper shaft Example

<< 1. Overview of surge hopper configuration and slag discharge processing in surge hoppers≫
The damper shaft according to the present embodiment is used for a surge hopper that stores sinter discharged from a rotary kiln (see FIG. 1) after drying and partial reduction treatment are performed on ore in ferronickel smelting. It is for opening and closing the damper.

  First, prior to the description of the damper shaft, an outline of the surge hopper 1 that stores sinter is described. FIG. 2 is a schematic cross-sectional view of the surge hopper 1 and the sinter hopper 8 provided at the lower end of the surge hopper 1.

  As shown in FIG. 2, the surge hopper 1 has a surge hopper 1A for storing the slag discharged from the rotary kiln, and a slag hopper 8 for charging the sinter with a predetermined amount stored in the surge hopper 1A. And a damper 10 as an opening / closing mechanism. The damper 10 has a flapper type structure as shown in FIG. 3, and is opened and closed by moving a cylinder 12 installed outside the surge hopper 1 and rotating around the damper shaft 11 of the damper 10. To do. A caster 14 is provided around the damper 10 as a refractory (see FIG. 3).

  Further, as shown in FIG. 2, the slag hopper 8 provided subsequently to the lower end of the surge hopper 1 includes, for example, two slag hopper parts 8a and 8b (hereinafter referred to as “first slag hopper part 8a”). , Also referred to as “second sinter hopper portion 8b”), and the slag hoppers 8a and 8b are sequentially charged with sinter from the surge hopper 1. In the case of the configuration in which the two sinter hoppers 8a and 8b are provided in this manner, the damper 10 provided in the surge hopper 1 is sequentially charged with the sinter into the respective sinter hoppers 8a and 8b. In order to control this, two dampers 10a and 10b (hereinafter also referred to as "first damper 10a" and "second damper 10b") are provided so as to correspond to the respective sinter hopper portions 8a and 8b.

  Specifically, the smelter temporarily stored in the surge hopper 1A of the surge hopper 1 is disposed inside the surge hopper 1A by, for example, opening one damper 10a (first damper 10a) of the surge hopper 1. The sinter is charged into the first sinter hopper 8a. Then, the weight of the sinter is measured using the load cell 13a provided in the first sinter hopper 8a, and when the measured value reaches a predetermined weight, the first damper 10a of the surge hopper 1 is used. Is closed, and charging of the sinter into the first sinter hopper 8a is stopped. Then, the damper provided in the lower end of the 1st sinter hopper part 8a opens, and the sinter of predetermined weight is discharged | emitted in a sinter container. When the discharge of the sinter into the sinter container is finished, the damper of the first sinter hopper 8a is closed.

  When the first damper 10a is closed and charging of the sinter into the first sinter hopper portion 8a is completed, the other damper 10b (second damper 10b) of the surge hopper 1 is subsequently opened, and the surge The sinter in the hopper part 1A is charged into the second sinter hopper part 8b. Then, as described above, the slag charged in the second sinter hopper 8b is weighed by the load cell 13b, and the charging is stopped when a predetermined weight of sinter is stored, When the damper provided at the lower end of the second sinter hopper 8b is opened, the sinter is discharged into the sinter container.

  In this way, after the first damper 10a (or the second damper 10b) of the surge hopper 1 is opened, the sinter is passed through the first sinter hopper part 8a (or the second sinter hopper part 8b). Then, the second damper 10b (or the first damper 10a) of the surge hopper 1 is opened and the sinter is discharged through the second sinter hopper part 8b (or the first sinter hopper part 8a). By repeating the operation of being discharged, the two ore hopper sections 8a and 8b described above are alternately used to sequentially discharge a predetermined weight of the ore into the ore container.

  As described above, the damper 10 of the surge hopper 1 is loaded with several tons of burned ore and is rotated around the damper shaft 11 in order to sequentially discharge the burned ore through the burned hopper 8. Efficient and accurate open / close control is required to discharge the sinter.

≪2. About damper shaft >>
FIG. 5 is a schematic diagram for explaining the configuration of the damper shaft according to the present embodiment. As shown in FIG. 5, the damper shaft 11 is made of a cylindrical steel material 21, and a cylindrical water passage 22 having the same central axis as the steel material 21 is provided inside the cylindrical steel material 21. ing. And this damper axis | shaft 11 satisfy | fills the following relational expression (I), when the diameter of the circular cross section of the column-shaped steel material 21 is set to D1, and the diameter (inner diameter) of the circular cross section of the water flow path 22 is set to D2.
0.2 × D1 ≦ D2 ≦ 0.55 × D1 (I)

The columnar steel material 21 constitutes the main structure of the damper shaft 11 that opens and closes the damper body, and includes a central portion 21A and end portions 21B (21B ₁ , 21B ₂ ). A damper main body is attached to the central portion 21 </ b> A of the steel material 21. Further, the end portion 21B has a gland portion, and prevents high-pressure gas or dust containing fine ore from being ejected to the outside while preventing the rotation of the damper shaft 11 from being hindered. I try to prevent it.

  Specifically, a ground box 15 is provided at the ground portion in the end portion 21B, for example, as shown in FIG. The ground box 15 accommodates a gland packing 16 for preventing outflow of high temperature gas and the like and a gland presser 17 for fixing and holding the gland packing 16. The material and insertion position of the gland packing 16 may be appropriately selected in consideration of the desired heat-resistant temperature.

  The material (steel type) of the steel material 21 is not particularly limited as long as it conforms to the use conditions. However, it may cause a problem at least between the periodic inspection and the periodic inspection, that is, for example, the operation period of 6 months. It is preferable that it is not. Specifically, for example, SUS310S is preferably used. Since SUS310S has high heat resistance and oxidation resistance, it is preferable to use the steel material 21 made of SUS310S because the frequency of occurrence of defects due to the heat of the ore at about 800 ° C. can be reduced.

  Further, the length of the cylindrical steel material 21, that is, the length (full length) of the damper shaft 11 including the central portion 21A and the end portion 21B, is the width of the mounting position of the damper 10 in the surge hopper 1. The above is preferable. As will be described later, the columnar steel material 21 is provided with a water passage 22 having the same central axis, and the damper shaft 11 is cooled (water cooled) by flowing cooling water through the water passage 22. Can be done. At this time, when the total length of the steel material 21 is equal to or larger than the width of the mounting position of the damper 10 in the surge hopper 1, the cooling water can be supplied from the outside of the surge hopper 1. Thereby, it can prevent more effectively that the water | moisture content resulting from cooling water penetrate | invades into the inside of the surge hopper 1, and a water | moisture content mixes into a sinter.

  The water passage 22 is provided inside the columnar steel material 21 as described above, and is provided in a columnar shape so that the center axis of the steel material 21 is the same. As shown in FIG. 5, the water passage 22 is formed continuously (consistently) over the entire length of the steel material 21 constituting the main body of the damper shaft 11 in the major axis direction. Cooling water for water cooling is passed. Specifically, a cooling water pipe (hose) 23 for supplying and discharging cooling water is connected to the end of the water passage 22, for example, from X to Y in FIG. 5. The cooling water passes through the water passage 22 in one direction toward the head. By cooling the steel material 21 with the cooling water through the water passage 22 in this way, it is possible to prevent the damper shaft 11 from being deformed by the heat of the high-temperature sinter.

  Here, considering that the damper shaft is a long columnar shape, for example, a water passage is provided only at both ends of the damper shaft, and the water passage provided only at both ends is provided. It is conceivable that the cooling water is passed through the position corresponding to the inside of the surge hopper of the damper shaft without passing the cooling water. Specifically, for example, as shown in FIG. 6, in the damper shaft 50, a water passage is not provided in the central portion of the steel material 51 constituting the main part of the damper shaft 50, and the water passage is provided only at both end portions of the steel material 51. A method may be considered in which one is provided with two water passages 52 (one water passage is provided on one damper shaft (water passages 52a and 52b), and cooling water is circulated through the water passages 52 at the respective end portions. It is considered that the strength of the damper shaft 50 can be maintained by adopting a configuration in which a water passage is not provided in the central portion of the damper shaft 50.

  However, when the water passage 52 is provided only at both end portions of the damper shaft 50 as shown in FIG. 6 and the water passage is not provided in the central portion, cooling of the central portion becomes insufficient. There is a possibility that deformation and breakage of the damper shaft 50 due to the heat of the ore at about 800 ° C. cannot be effectively prevented.

  Further, in the structure in which the cooling water is circulated at the end portion of the damper shaft 50 as shown in FIG. 6, cooling is performed at the tip of the water-cooled portion (Z portion in FIG. 6) provided in the longitudinal direction with respect to the damper shaft 50. The direction of water flow will be reversed. Then, in the place where the direction of the flow is reversed, the foreign matter mixed in the cooling water accumulates, the blockage occurs at that place, and the cooling effect is deteriorated due to poor circulation of the cooling water. For example, when industrial water drawn from rivers is used as cooling water for cooling, foreign matter that causes poor circulation due to accumulation is river sand mixed in the cooling water, and deposited very easily. It takes time and cost to remove foreign substances. Furthermore, in such a structure, it is necessary to provide at least two water passages 52 (one at each end) on the damper shaft 50, and there are many places to check for clogging of the cooling water. Four expensive flexible hoses (cooling water pipes) 53 (one for each of the water passages 52) 53 are required to pass through, so that it is difficult to efficiently cool economically.

Therefore, in the damper shaft 11 according to the present embodiment, the column-shaped water passage 22 is provided in the columnar steel material 21 constituting the damper shaft 11 so that the steel material 21 and the central axis are the same. The steel material 21 is continuously provided over the entire length in the major axis direction, and cooling water is passed through the water passage 22. And at this time, in this Embodiment, when the diameter of the circular cross section of the steel material 21 is set to D1, and the diameter (inner diameter) of the circular cross section of the water flow path 22 is set to D2, with the steel material 21 so that the following relational expression may be satisfied. The water passage 22 is configured.
0.2 × D1 ≦ D2 ≦ 0.55 × D1 (I)

  In the damper shaft 11 according to this embodiment, the water passage 22 is continuously provided over the entire length in the long axis direction of the steel material 21 inside the columnar steel material 21 as described above. Since the cooling water is also passed through the central portion of the long axis direction of 11 and the entire damper shaft 11 is constantly cooled during operation, thermal deformation and breakage of the damper shaft 11 including the central portion are effectively suppressed. be able to.

  In addition, since the water flow direction 22 can be made one direction by using one pipe for the water flow path 22 through which the cooling water flows, the flow of the cooling water becomes smooth. For example, for cooling the structure shown in FIG. In comparison, the occurrence of clogging of cooling water can be prevented. Furthermore, since the number of cooling water pipes (hoses) 23 for supplying and discharging cooling water can be two, the burden of inspection and replacement can be reduced.

  Further, since the water passage 22 is cylindrical and the central axis thereof is the same as the cylindrical steel material 21, the thickness is uniform and the heat effect is uniformly received. Deformation can also be suppressed.

  And in particular, by maintaining the strength of the steel material 21 by configuring each of the steel material 21 and the water passage 22 integrally formed therein with a diameter that satisfies the relational expression (I), It is possible to effectively prevent defects such as deformation of the steel material 21 due to the heat of the sinter of about 800 ° C. during the operation period, breakage of the damper shaft 11, and opening / closing failure of the damper 10 during the operation period by increasing the hot strength. it can.

  Regarding relational expression (I), if D2> 0.55 × D1, the damper shaft 11 is cooled, but the strength of the damper shaft 11 is insufficient. Specifically, for example, deformation such as bending of the damper shaft 11 occurs. In this way, cracks are likely to occur at locations where deformation has occurred, and when cracks occur, cooling water leaks from the cracked locations, moisture is mixed into the sinter, and the sinter containing moisture is loaded into the electric furnace. There is a possibility of being entered.

  On the other hand, when D2 <0.2 × D1, the damper shaft 11 is not sufficiently cooled, resulting in a problem. That is, for example, when industrial water having a pressure of about 0.1 to 0.5 MPa is used as cooling water, the inner diameter of the water passage 22 provided in the damper shaft 11 is smaller than “0.2 × D1”. Then, the temperature for maintaining the strength of the damper shaft 11 (about 500 ° C. or less) cannot be maintained. Therefore, when D2 <0.2 × D1, deformation and breakage due to heat from the sinter cannot be sufficiently prevented.

  As described above, the diameter (D1) of the steel material 21 constituting the damper shaft 11 is not particularly limited as long as the D1 and the diameter (D2) of the circular cross section of the water passage 22 can satisfy the relational expression (I). However, specifically, it is preferable that 100 mm ≦ D1 ≦ 150 mm. If D1 is less than 100 mm, the required strength may not be sufficiently obtained. On the other hand, if D1 exceeds 150 mm, the damper 10 itself increases in size, and the cylinder 12 for operating the damper 10 also becomes large. This increases the size of the entire facility and significantly increases the capital investment.

  The size of the surge hopper 1 is not particularly limited, but the weight applied to the damper 10, that is, the combined weight of the slag stacked on the damper 10 and the weight of the damper 10 is about 1 to 4 t. It is preferable that the size be such that If the weight is less than 1 t, the amount of sinter that can be temporarily stored in the surge hopper 1 is small, so the frequency of acceptance of the sinter from the surge hopper 1 to the sinter hopper 8, that is, the frequency of opening and closing the damper 10 is It will increase significantly. For this reason, wear of mechanical parts such as the damper shaft 11 and the cylinder 12 becomes remarkable. On the other hand, when the weight exceeds 4 t, the weight applied to the damper 10 and the damper shaft 11 increases, and therefore, a design change is required to make the structure resistant to the heat received from the high-temperature sinter or larger weight.

  The method of passing the cooling water to the water passage 22 is not particularly limited, and a flexible cooling water pipe (hose) 23 is connected to both ends of the cylindrical water passage 22, and the cooling water pipe 23 is connected thereto. The cooling water can be supplied to the inside of the water passage 22 and the cooling water passing through the water passage 22 can be discharged. Specifically, as shown in FIG. 5, a cooling water pipe (cooling water supply) for supplying cooling water to the water passage 22 at one end of the water passage 22 (the X-side end in FIG. 5). Piping) 23a is connected, and a cooling water pipe (cooling water discharge pipe) 23b for discharging the cooling water that has passed through the water passage 22 is connected to the other end (Y side end in FIG. 5). . In this manner, the two cooling water pipes 23a and 23b are connected to the water passage 22 continuously provided in the cylindrical steel material 21 constituting the damper shaft 11 over the major axis direction thereof. The damper shaft 11 can be effectively cooled by allowing cooling water to flow through the water passage 22 in one direction. Thereby, deformation | transformation and breakage by the heat | fever of a high temperature sinter can be prevented, maintaining the intensity | strength of the damper shaft 11. FIG.

  Here, at both ends of the water passage 22, in order to connect the cooling water pipe 23, connection portions 24 (24 a, 24 b) (indicated by dotted lines in FIG. 5) having female threads are formed. Is preferred. Specifically, a connecting portion 24 with a female thread cut is formed at the end of the water passage 22 so that a connecting component with a male screw cut can be fitted separately, and a cooling water pipe 23 is attached to the connecting component. Try to connect. In this way, the end portion of the water passage 22 is configured to have a female thread, so that foreign matters such as dust can be removed from the end portion of the water passage 22 during maintenance such as replacement of the cooling water pipe 23. Can be prevented, and for example, the occurrence of blockage by foreign matter in the water passage 22 can be more effectively prevented.

  The length for applying the female screw at both ends of the water passage 22 (the length of the connecting portion 24) is long enough that the connecting parts connected to the connecting portion 24 with the female screw cut off do not fall off during operation. There is no particular limitation as long as there is. For example, it is preferable to adjust including the length of the columnar steel material 21 so that the inner end of the female screw does not become deeper than the outside of the surge hopper. This is preferable because a high temperature region inside the surge hopper 1 can be avoided.

As described in detail above, the damper shaft 11 according to the present embodiment is made of the columnar steel material 21, and the columnar passage is made inside the steel material 21 so that the steel material 21 and the central axis are the same. The water channel 22 is continuously provided over the entire length of the steel material 21 in the major axis direction, and the cooling water is passed through the water channel 22. And in the relationship between the diameter (D1) of the circular cross section of the steel material 21 and the diameter (inner diameter) (D2) of the circular cross section of the water passage 22, the following relational expression is satisfied.
0.2 × D1 ≦ D2 ≦ 0.55 × D1 (I)

  According to such a damper shaft 11, the damper shaft 11 of the damper 10 used in the surge hopper 1 that temporarily stores the burned ore from the rotary kiln 2 can effectively prevent deformation and breakage due to heat received from the burned ore. Therefore, the opening / closing control of the damper 10 associated with the discharge processing of the sinter can be performed efficiently and accurately.

  In addition, regarding the safety of work, inspection and repair of the surge hopper 1 and the like containing high-temperature sinter is accompanied by the risk of heat stroke due to burns and hot work, but by using the damper shaft 11 as described above, Since maintenance becomes easy and the need for inspection and repair can be reduced, the safety of work can be greatly improved.

≪3. Examples >>
Hereinafter, the damper shaft according to the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples.

[Example 1]
When charging the sinter obtained from the rotary kiln used in ferronickel smelting into the sinter container, the surge hopper using the damper shaft 11 as shown in FIG. It operated for 6 months. The steel type (material) of the columnar steel material 21 constituting the damper shaft was SUS310S. In addition, the weight of the sinter charged in the sinter container was set to about 13 tons.

  Here, regarding the damper shaft 11, the diameter of the circular cross-section of the columnar steel material 21 constituting the damper shaft 11 is “D1”, and the diameter (inner diameter) of the water passage 22 provided in the steel material 21. ) Is “D2”, the relationship between D1 and D2 satisfies “0.2 × D1 ≦ D2 ≦ 0.55 × D1”.

  As a result of operation for 6 months, no deformation or breakage of the damper shaft 11 used in the surge hopper occurred. Further, no blockage occurred in the water passage 22 provided inside the steel material 21 of the damper shaft 11.

  Subsequently, the same damper shaft 11 was used for further 6 months of operation, but the damper shaft 11 was not deformed or broken at all, and the water passage 22 was not blocked.

[Comparative Example 1]
When charging the ore obtained from the rotary kiln used in ferronickel smelting into the ore container, the surge hopper using the damper shaft 50 as shown in FIG. It operated for 6 months. The steel type (material) of the columnar steel material 51 constituting the damper shaft 50 was S45C. In addition, the weight of the sinter charged in the sinter container was set at about 13 tons.

  Here, in the steel material 51 constituting the damper shaft 50, as shown in FIG. 6, a total of four water passages 52, each having two end portions, are provided at both end portions, and at each end portion, The damper shaft 50 was cooled by circulating cooling water.

  As a result of operation for 6 months, a part of the damper shaft 50 used in the surge hopper was carbonized and embrittled by the high-temperature gas, and the damper shaft 50 was thinned by wear. Then, when the same damper shaft 50 was continuously used, breakage occurred when it was used for another 4 months, and the operation was stopped. The replacement work of the damper shaft 50 that caused the breakage took a long time of about 70 hours, and a large pause loss occurred.

  Further, the water passage 52 was blocked during the operation period of 6 months. Therefore, it is necessary to perform an air blow to eliminate clogging of the water passage 52. When the water passage 52 was confirmed, blockage due to the scale occurred, and the water flow amount in the water passage 52 was reduced to 50% or less, and the maintenance work took about one hour.

[Comparative Example 2]
When charging the ore obtained from the rotary kiln used in ferronickel smelting into the ore container, the surge hopper using the damper shaft 50 as shown in FIG. It operated for 6 months. The steel type (material) of the columnar steel material 51 constituting the damper shaft was SUS310S. In addition, the weight of the sinter charged in the sinter container was set at about 13 tons.

  Here, in the steel material 51 constituting the damper shaft 50, as shown in FIG. 6, a total of four water passages 52, each having two end portions, are provided at both end portions, and at each end portion, The damper shaft 50 was cooled by circulating cooling water.

  As a result of operation for 6 months, a part of the damper shaft 50 used in the surge hopper was embrittled by high-temperature gas, and the damper shaft 50 was thinned due to wear. When the same damper shaft 50 was continuously used, breakage occurred when it was used for another 4 months. That is, even when SUS310S having a relatively high durability is used as the steel material 51, it is understood that the damper shaft 50 having the structure shown in FIG. 6 cannot effectively prevent deformation and breakage. It was. In the operation of Comparative Example 2, the water passage 52 was blocked during the operation period of 6 months.

DESCRIPTION OF SYMBOLS 1 Surge hopper 2 Rotary kiln 3 Burning container 4 Carriage cart 5 Furnace crane 6 Roadside bin 7 Electric furnace 8, 8a, 8b Burning hopper 10, 10a, 10b Damper 11 Damper shaft 12 Cylinder 13 (13a, 13b) Load cell 14 Caster 21 Steel material 22 Water passage 23, 23a, 23b Cooling water piping 24 Connection part

Claims (6)

A damper shaft for opening and closing a damper used in a surge hopper for storing burned ore in ferronickel smelting,
Made of cylindrical steel,
In the inside of the columnar steel material, a column-shaped water passage having the same central axis as the steel material is provided continuously over the long axis direction of the steel material,
When the diameter of the steel material is D1, and the diameter of the circular cross section of the water passage is D2,
0.2 × D1 ≦ D2 ≦ 0.55 × D1
A damper shaft characterized by satisfying the relationship   2. The damper shaft according to claim 1, wherein a total length of the steel material is equal to or greater than a width of a mounting position of the damper in the surge hopper.   The damper shaft according to claim 1 or 2, wherein female threads to which a cooling water supply pipe is connected are cut at both ends of the water passage.   The damper shaft according to any one of claims 1 to 3, wherein a steel type of the steel material is SUS310S.   The damper shaft according to any one of claims 1 to 4, wherein a diameter D1 of the steel material is 100 mm or more and 150 mm or less. The said surge hopper is comprised in the magnitude | size from which 1 to 4t is the sum total weight of the slag piled up on the damper and the dead weight of this damper, The any one of Claim 1 thru | or 5 characterized by the above-mentioned. The damper shaft according to item.

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