JP2004256848A - Agitation type desulfurizing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an agitation type desulfurizing apparatus capable of reducing the impact load applied to a stirring machine and a guide, adjusting the dipping depth of an impeller freely even during agitation and effectively cooling the exposed metal portion of a steel shaft of an impeller and a driving shaft connected tereto. <P>SOLUTION: In the stirring type desulfurizing apparatus composed of a carriage for storing an impeller driving device, the driving shaft extended downward in this carriage, the stirring machine having the impeller connected with the driving shaft and stirring molten metal, an ascending/descending device for ascending/descending the stirring machine to the molten metal surface and the guide for guiding the ascent/descent of the stirring machine, the carriage is provided with a roller with pushing tool rolling on the guide. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an agitation type desulfurization apparatus mainly used for desulfurizing hot metal, and more particularly to an agitation type desulfurization apparatus provided with means for reducing damage due to vibration and heat in an agitation apparatus using an impeller.
[0002]
[Prior art]
It is known that sulfur (S) in steel has an adverse effect on product quality, and a desulfurization treatment for removing a sulfur content by adding a desulfurizing agent such as lime or soda ash to hot metal has been performed. As one of the processing apparatuses, there is a stirring type desulfurization apparatus for charging lime or the like while stirring hot metal with an impeller, and is used because of high desulfurization efficiency.
[0003]
However, in an agitated desulfurization system that stirs hot metal at a rotation speed of up to 150 rpm with an impeller having huge wings of 1.5 m across, vibration occurs due to abnormal rotation such as vibration generation due to impeller wear and rotation fluctuation. I do. If this vibration is allowed, the life of the equipment and the life of the refractory portion of the impeller are shortened. Therefore, the impeller driving device is normally operated while being pressed against the guide and fixed. Further, the portion of the impeller for stirring the hot metal is made of a refractory, but the exposed metal portion of the iron shaft forming the impeller core and the iron drive shaft connected thereto are heated to 400 ° C. or higher. In addition, the material is significantly deteriorated due to repeated fatigue at high temperatures. Therefore, it is often necessary to stop the apparatus and perform inspection, repair, replacement of parts, and the like.
[0004]
To solve such a problem, Patent Document 1 discloses a stirrer having an impeller and a driving device thereof, a guide frame for guiding the stirrer up and down, and a plurality of pushers for fixing the stirrer to the guide frame. A stirrer-type desulfurization apparatus provided with a pressing tool is provided on a guide frame.
[0005]
[Patent Document 1]
JP-A-2002-363627
[Problems to be solved by the invention]
In order to improve the desulfurization efficiency, it is important to adjust the immersion depth of the impeller and perform appropriate stirring while observing the impeller wear state, slag properties, vortex state, and the like. However, in the device proposed above, the stirrer is fixed on the guide by the pusher, and the impeller immersion depth cannot be changed. Therefore, every time the impeller immersion depth is adjusted, the rotation of the impeller must be stopped or remarkably reduced to adjust the immersion depth, and then the operation must be restarted, which causes a problem of poor operability.
[0007]
In addition, the above proposal does not solve the problem that the exposed metal part of the iron shaft of the impeller and the drive shaft connected to it are heated to a high temperature. And replace the impeller iron shaft.
[0008]
In view of the above problems, the present invention aims to reduce the impact load acting on the stirrer and the guide, adjust the immersion depth of the impeller freely even during stirring, and further connect the metal shaft to the exposed metal portion of the iron shaft of the impeller. It is an object of the present invention to propose an agitation type desulfurization device capable of effectively cooling a driven shaft.
[0009]
[Means for Solving the Problems]
A stirrer-type desulfurization apparatus according to the present invention includes a stirrer having a carriage for storing an impeller drive unit, a drive shaft extending below the carriage, and an impeller connected to the drive shaft to stir molten metal; An agitation type desulfurization apparatus comprising an elevating device for elevating and lowering a surface and a guide for guiding the agitator up and down, the carriage includes a roller with a pusher for rolling on the guide.
[0010]
The device 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]
BEST MODE FOR CARRYING OUT 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 type desulfurization apparatus according to one embodiment of the present invention. As in the conventional apparatus, the stirring type desulfurization apparatus 1 includes a guide 2 erected with a hot metal pot 40 filled with hot metal 41 interposed therebetween, a stirrer 3 for stirring the hot metal in the hot metal pot 40, and a stirrer. And an elevating device 35 for elevating and lowering the guide 3 along the guide 2.
[0012]
The stirrer 3 includes a carriage 4 that houses an impeller driving 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 stirrer 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 pusher is interposed between the carriage 4 and the guide 2. As shown in FIG. 2, the roller with pusher 10 has an end supported by the carriage 4 and has a hydraulic cylinder 11 for pressing the guide 2 toward the guide 2 and a bracket 13 provided at the end of the rod 12. It is composed of a roller 14 that is pivotally supported.
[0014]
The guide has a convex rail 18 and the roller has a V-shaped groove 15. The roller 14 is constantly pressed against the rail 18 by the hydraulic cylinder 11 at a predetermined pressure, so that no gap is formed between the roller 14 and the rail 18. Accordingly, the stirrer can be moved up and down along the guide without play, so that 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]
The rollers 10 with pushers of the present embodiment are provided at a total of eight at the four corners of the upper and lower surfaces of the carriage 4, but the mounting position and the number may be determined as necessary. Further, the roller 14 has the V-shaped groove 15 that fits into the convex rail 18 of the guide 2, but any structure may be used as long as the roller 14 rolls on the guide along the guide 2. Its 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 is composed of a refractory wing 7 and an iron shaft 8 forming a core thereof, and is connected to the drive shaft 5 via a flange 9 (9A, 9B). The temperature of the exposed metal portion of the iron shaft 8 near the flange 9 and the temperature of 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 iron shaft 8 of the impeller and the drive shaft 5 connected thereto is provided.
[0017]
The cooling device 20 has a spray nozzle 21 for spraying mist-like water on the metal exposed portion of the iron shaft 8 of the impeller, the flange 9 and each portion of the drive shaft 5, and a pump Mp for appropriately supplying water to the spray nozzle 21. are doing. This cooling device 20 utilizes the heat of vaporization of water, and provides air cooling inside the iron shaft (high safety but low cooling capacity) and water cooling (high cooling capacity but high danger of steam explosion. Inferior) and 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 a water flow of 20 l / min. In addition, the number of sprays to be installed, the mounting position, and the like are appropriately determined depending on the structure of the desulfurization apparatus, desulfurization processing conditions, and the like.
[0018]
【The invention's effect】
ADVANTAGE OF THE INVENTION The stirring type desulfurization apparatus by this invention can reduce the impact load which acts on a stirrer, and can adjust the immersion depth of an impeller as needed. As a result, the time required for desulfurization treatment per charge can be reduced from 15 minutes or less to 20 minutes or less, and the desulfurizing agent basic unit can be reduced by 15% or more. Further, 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 2,000 charges to 5,000 charges or more.
[Brief description of the drawings]
FIG. 1 is a front view showing an outline of an apparatus of one embodiment of a stirring type desulfurization apparatus according to the present invention.
FIG. 2 is a plan view of a pressing part of the apparatus of FIG.
[Explanation of symbols]
1: stirrer type desulfurizer 2: guide 3: stirrer 4: carriage 5: drive shaft 6: impeller 7: blade 8: iron shaft 9: flange 10: roller 11 with pusher: cylinder 12, rod 13: bracket 14: Roller 15: V-shaped groove 18: Rail 20: Cooling device 21: Spray nozzle 30: Impeller drive device 31: Motor 32: Reducer 35: Lifting device 36: Wire 40: Hot metal pot 41: Hot metal

Claims (2)

A carriage storing the impeller driving device, a stirrer having a drive shaft extending below the carriage, and an impeller connected to the drive shaft to stir the molten metal; a lifting device for moving the stirrer up and down with respect to the bath surface; A stirrer-type desulfurizer comprising a guide for guiding the stirrer up and down,
A stirrer-type desulfurization apparatus, comprising: a roller with a pusher that rolls on a guide on the carriage. 2. The agitated desulfurization apparatus according to claim 1, further comprising a cooling device for spray cooling the exposed metal portion of the iron shaft of the impeller and the drive shaft connected thereto.

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