JP4123973B2 - Stirring desulfurizer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an agitation desulfurization apparatus used mainly for desulfurization of hot metal, and more particularly to an agitation desulfurization apparatus in which a desulfurization apparatus that performs agitation with an impeller is provided with means for reducing damage due to vibration and heat.
[0002]
[Prior art]
Sulfur (S) in steel is known to adversely affect product quality, and desulfurization treatment is performed in which sulfur is removed by introducing a desulfurizing agent such as lime or soda ash into the hot metal. As one of the treatment apparatuses, there is an agitation type desulfurization apparatus in which lime or the like is added while agitating hot metal with an impeller, and is utilized because of high desulfurization efficiency.
[0003]
However, in the agitation-type desulfurization equipment that stirs hot metal at a rotation speed of up to 150 rpm with an impeller with a huge blade of 1.5 m across, vibration occurs due to vibration due to impeller wear and rotation abnormalities such as rotational fluctuations. . If this vibration is allowed, the equipment life and the life of the refractory part of the impeller are shortened, so the impeller driving device is pressed against the guide and normally operated. In addition, the part that stirs the hot metal of the impeller is made of a refractory material, but the exposed metal part of the iron shaft that forms the impeller core and the iron drive shaft that is connected to it are heated to 400 ° C or higher. In addition, material deterioration due to repeated fatigue at high temperatures is significant. For this reason, it is often necessary to stop the equipment to perform inspections, repairs, parts replacement, and the like.
[0004]
With respect to such a problem, Patent Document 1 discloses a stirrer provided with an impeller and its driving machine, a guide frame that guides the raising and lowering of the stirrer, and a plurality of pushers for fixing the stirrer to the guide frame. In a stirring-type desulfurization apparatus including a tool, a stirring-type desulfurization apparatus is proposed in which the pressing tool is installed on a guide frame.
[0005]
[Patent Document 1]
JP 2002-363627 A [0006]
[Problems to be solved by the invention]
In order to improve the desulfurization efficiency, it is important to adjust the impeller immersion depth while observing the wear state of the impeller, the slag properties, the state of the vortex, etc., and perform appropriate stirring. However, in the apparatus proposed above, the stirrer is fixed on the guide with a pusher, and the impeller immersion depth cannot be changed. Therefore, every time the impeller immersion depth is adjusted, rotation of the impeller is stopped or the rotation is remarkably reduced to adjust the immersion depth, and then the operation must be restarted, resulting in poor operability.
[0007]
The above proposal does not solve the problem that the exposed metal part of the iron shaft of the impeller or the drive shaft connected to the impeller is heated to a high temperature. For this reason, the device is stopped frequently and inspected and repaired. And the iron shaft of the impeller must be replaced.
[0008]
In view of the above problems, the present invention can reduce the impact load acting on the stirrer and the guide, and can freely adjust the immersion depth of the impeller even during stirring. An object of the present invention is to propose a stirring type desulfurization apparatus capable of effectively cooling the drive shaft.
[0009]
[Means for Solving the Problems]
A stirring desulfurization apparatus according to the present invention includes a carriage that houses an impeller driving device, a driving shaft that extends below the carriage, an agitator that is connected to the driving shaft and that stirs molten metal, and the stirrer is bathed. An agitation desulfurization apparatus comprising an elevating device that moves up and down relative to a surface and a guide that guides the elevating and lowering of the agitator. The roller includes a roller with a pusher that rolls on the guide.
[0010]
The apparatus may include a cooling device for spray cooling the exposed metal portion of the iron shaft of the impeller and the drive shaft connected thereto.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be specifically described with reference to the drawings. FIG. 1 is a front view showing an outline of a stirring desulfurization apparatus according to one embodiment of the present invention. As with the conventional apparatus, the stirring desulfurization apparatus 1 is composed of a guide 2 erected with a hot metal ladle 40 filled with hot metal 41, an agitator 3 for stirring hot metal through the hot metal ladle 40, and an agitator And an elevating device 35 for elevating 3 along the guide 2.
[0012]
The stirrer 3 includes a carriage 4 that houses an impeller drive device 30 including a motor 31 and a speed reducer 32, a drive shaft 5 that extends below the carriage 4, and an impeller 6 that is connected to the drive shaft 5 and stirs molten metal. The agitator 3 is moved up and down by winding or pulling out the wire 36 from which the carriage 4 is suspended by the motor Mw.
[0013]
In the present invention, a roller 10 with a pressing tool is interposed between the carriage 4 and the guide 2. As shown in FIG. 2, the roller 10 with a pressing tool is supported by a hydraulic cylinder 11 that is supported by the carriage 4 and presses the guide 2 toward the guide 2, and a bracket 13 that is provided at the end of the rod 12. It consists of a roller 14 that is pivotally supported.
[0014]
The guide has a convex rail 18 and the roller is provided with a V-shaped groove 15. Further, the roller 14 is always pressed against the rail 18 by a predetermined pressure by the hydraulic cylinder 11, so that no gap is generated between the roller 14 and the rail 18. Thereby, the stirrer can move up and down along the guide without rattling, and the impact load acting on the stirrer and the guide can be reduced, and the immersion depth of the impeller can be adjusted as necessary.
[0015]
Note that a total of eight rollers 10 with pressing tools in this embodiment are provided at the four corners of the upper and lower surfaces of the carriage 4, but the mounting positions and the number thereof may be determined as necessary. Further, the roller 14 has a V-shaped groove 15 that fits into the convex rail 18 of the guide 2, but the roller 14 may have a structure that rolls on the guide along the guide 2. The structure does not matter.
[0016]
In the present invention, it is preferable to further provide a spray device for cooling the exposed metal portion of the iron shaft 8 of the impeller and the drive shaft 5 connected thereto. The impeller 6 includes a refractory wing 7 and an iron shaft 8 forming a core portion thereof, and is connected to the drive shaft 5 via flanges 9 (9A, 9B). The exposed metal portion of the iron shaft 8 near the flange 9 and the iron drive shaft 5 reach 400 ° C. or higher during operation of the apparatus. Therefore, in the present invention, a cooling device capable of efficiently cooling the exposed metal portion of the impeller iron shaft 8 and the drive shaft 5 connected thereto is provided.
[0017]
The cooling device 20 has a spray nozzle 21 that blows mist of water on the exposed metal part of the iron shaft 8 of the impeller, each part of the flange 9 and the drive shaft 5, and a pump Mp that supplies water appropriately to the spray nozzle 21. is doing. This cooling device 20 uses the heat of vaporization of water, making it safe for air cooling inside the iron shaft (high safety but low cooling capacity) and water cooling (high cooling capacity but danger of steam explosion). Can be cooled safely and efficiently. For example, during operation (about 15 minutes), the temperature of the iron shaft can be reduced to 300 ° C. or less by spray cooling with an amount of water of 20 l / min. Note that the number of installations, the installation position, and the like of the spray are appropriately determined depending on the structure of the desulfurization apparatus, the desulfurization treatment conditions, and the like.
[0018]
【The invention's effect】
The stirring-type desulfurization apparatus according to the present invention can reduce the impact load acting on the stirrer and adjust the impeller immersion depth as necessary. As a result, the desulfurization processing time per charge can be reduced to 15 minutes or less from the conventional 20 minutes, and the desulfurization agent basic unit can be reduced by 15% or more. Furthermore, by spray cooling, the iron shaft temperature of the impeller can be reduced to 300 ° C. or less, and the life of the iron shaft can be extended from 2000 charges to 5000 charges or more.
[Brief description of the drawings]
FIG. 1 is a front view showing an outline of an apparatus of an embodiment of an agitation desulfurization apparatus according to the present invention.
FIG. 2 is a plan view of a pusher portion of the apparatus of FIG.
[Explanation of symbols]
1: Stirring desulfurization equipment
2: Guide
3: Stirrer
4: Carriage
5: Drive shaft
6: Impeller
7: Wings
8: Iron shaft
9: Flange
10: Roller with pusher
11: Cylinder
12: Rod
13: Bracket
14: Laura
15: V-shaped groove
18: Rail
20: Cooling device
21: Spray nozzle
30: Impeller drive unit
31: Motor
32: Reducer
35: Lifting device
36: Wire
40: Hot metal hot pot
41: Hot metal

Claims (2)

A carriage for storing an impeller drive device, a drive shaft extending below the carriage, an agitator having an impeller connected to the drive shaft and stirring molten metal, and an elevating device for raising and lowering the stirrer relative to the bath surface; In the agitation desulfurization apparatus comprising a guide for guiding the raising and lowering of the agitator,
An agitation-type desulfurization apparatus comprising a roller with a pusher that rolls on a guide on the carriage. The stirring desulfurization apparatus according to claim 1, further comprising a cooling device for spray-cooling a metal exposed portion of the iron shaft of the impeller and a drive shaft connected thereto.

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