JPH0389117A - Weighing device for refining furnace - Google Patents

Abstract

PURPOSE:To improve weighing accuracy by providing a tension rod which is inserted through a supporting device provided at the specified part on the outer surface part of a furnace casing in an extending shape on a weighing gage. CONSTITUTION:A weighing gage 20 is held with a holding tool 4a which is provided on a trunnion ring 4 and a holding tool 24a of a tension rod 24. The tension rod 24 is suspended through the bottom part of a supporting device 5 which is provided on the outer surface of a furnace casing in an extending shape. When a refining furnace is inclined, the lateral deviation is prevented with side guides 28. When the furnace casing is turned over, the total value of the spring loads of Belleville springs 22 of two rods and the total value of the weights of furnace chambers are applied on the rod 24. Gaps are not formed between the upper and the lower surfaces of the weighing gage 20, and impact load is not applied. With respect to heat generated in the refining process, the rod 24 is cooled with cooling liquid 27. The preset load of the spring 22 is decreased, and tensile load which is applied on the weighing gage 20 becomes small. An error which appears as if the weight of molten metal were decreased is not brought about. Thus the weighing accuracy is improved.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a weighing device for a refining furnace.

[Prior Art] FIG. 6 shows a conventional refining furnace called a converter. 1 in the figure is a furnace body. The furnace body 1 is composed of a brick layer 2 that constitutes the furnace body body, and an iron skin 3 that covers the surface of the brick layer 2. The furnace body 1 is supported by a trunnion ring 4. That is, the trunnion ring 4 is fitted into the body of the furnace body 1. The furnace body 1 is supported on the trunnion ring 4 by its own weight via a support device 5 welded to the upper peripheral surface of the furnace body 1. The support device 5 is fixed integrally with the trunnion ring 4 by inserting a tapered plate called a cotter 7 into a hole in a convex portion 6 projecting above the trunnion ring 4. As a result, the furnace body 1 is prevented from falling off even when the refining furnace is upright, tilted, or overturned. In addition, 8 in the figure is a support device attached to the lower part, and is attached for the purpose of preventing lateral shaking when tilting or falling.

In addition, during operation, the furnace body 1 is tilted approximately 45 degrees toward the front of the furnace using the trunnion ring shaft 9 as the rotation axis to scrape and scrape.
Raw materials such as hot metal are charged into the tank. Thereafter, the furnace body 1 is returned to its original upright position and refining is performed. After refining, the molten steel is discharged by tilting the furnace body 1 approximately 90 degrees toward the rear of the furnace using the trunnion ring shaft 9 as a rotating shaft. Furthermore, in order to discharge the slag generated during refining, there is a task of inverting the furnace body 1 again by 90 to 180 degrees toward the front side of the furnace.

For the purpose of grasping the amount of molten metal in the smelting furnace operated in this manner, a load cell 11 is incorporated as shown in FIG. 7(A).

When the furnace body 1 is upright, the furnace body 1 is placed on the trunnion ring 4 via the upper support device 5 and a plurality of load cells 11 (usually provided at four locations on the circumferential surface of the furnace body l). It is placed on.

Further, during tilting, as shown in FIG. 7(C), the supporting device 15 is held down by a U-shaped stopper 50 fixed to the trunnion ring 4, thereby preventing the furnace body 1 from shifting laterally.

Furthermore, in the event of a fall, a plurality of stud bolts 12 connected to the lower surface of the trunnion ring 4 support the weight of the furnace body 1 to prevent it from falling.

A disc spring 13 is provided above the stud bolt 12 for the purpose of alleviating abnormal load and impact load when the vehicle falls. The disk spring 13 is set to have a load of 180 tons, and is designed to bend and absorb a load greater than that.

[Problem to be solved by the invention]

However, the conventional load cell 11 as described above has the following problems.

(2) Due to thermal expansion of the furnace body 1, the distance between the bearing surface 14 of the load cell 11 and the bearing surface 15 of the stud bolt 12 increases.

As a result, a gap is created in the part of the bolt 16 that fixes the stud bolt 12 at the lower part. For example, both sides have surface 14.
In the case where the distance between the holes 15 and 15 is 1440 mm and the temperature is 500° C., this gap will be about 8 mm. As a result, an impact load is generated when the furnace body 1 falls. Furthermore, this phenomenon is exacerbated by the thermal expansion of the stud bolt 12 itself.

As a countermeasure for this, the bolt 1 at the bottom of the stud bolt 12
6. Tightening must be adjusted frequently.

■Furthermore, in the furnace body 1, the steel shell 3 undergoes creep deformation due to internal pressure due to thermal expansion of the internal brick layer 2, as shown in Fig. 7 (
As shown by the broken line in B), the gap between the trunnion ring 4 and the furnace body 1 gradually becomes narrower. The time when this gap disappears is considered to be the end of the life of the furnace body 1. In other words, it is necessary to make the gap between the trunnion ring 4 and the furnace body 1 as large as possible. Therefore, if the stud bolt 12 is present in this area, as shown by the broken line in FIG. 7(A), this gap will become even narrower, and the life of the furnace body 1 will be reduced.

As a result, there was a problem that the furnace body 1 had to be partially or completely replaced frequently due to its short life.

The present invention has been made in view of these points, and provides a weighing device for a refining furnace that avoids the impact caused by thermal expansion when the furnace body falls over, and that allows the furnace body to be used for a long time. It is something.

[Means for Solving the Problems] The present invention provides an annular body fitted to the outer periphery of a furnace body, a support device protruding from a predetermined portion of the outer periphery, and a support device and the annular body. a rod interposed between the support device and the annular body; an elastic member pierced through the rod between the support device and the annular body; This weighing device for a refining furnace is characterized by comprising a weighing meter provided with a tension rod inserted through a support device, and a cooling mechanism for the rod.

[Function] According to the weighing device for a refining furnace according to the present invention, a weighing scale can be directly connected between the annular body fitted on the outer periphery of the furnace body and the support device protruding from the outer periphery of the furnace body. Since this is provided, the degree of freedom in the space occupied by the furnace body can be increased and the furnace body can be used for a long time. In addition, by providing a cooling mechanism for the rod and by minimizing the length of the tension rod to which the load is applied to reduce the thermal expansion margin for the same temperature difference, weighing accuracy can be improved.

[Examples] Examples of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory view showing a refining furnace to which a refining furnace weighing device according to an embodiment of the present invention is applied, and FIG. 2 is an explanatory view showing the configuration of the refining furnace weighing device according to the same embodiment. Note that the same parts as those in the scouring furnace shown in FIG. 6 are designated by the same reference numerals, and detailed description thereof will be omitted.

Support devices 5 are provided at four predetermined locations on the upper circumferential surface of the furnace body 1 constituting this scouring furnace.

Corresponding to the support device 5, support devices 8 are also provided at four locations on the lower part of the circumferential surface of the furnace body 1. A weighing scale 20 is interposed between each support device 5 and trunnion ring 4 .

The weighing scale 20 has a trunnion ring 4 as shown in FIG.
It is gripped by a gripper 4a provided above and a gripper 24a of a tension rod 24 that extends through the bottom of the support device 5 and hangs down. The tension rod 24 is connected to the cooling liquid 2
7 is circulated and held by a stopper 23. Also,
Two rods 2 are mounted on the trunnion ring 4 at predetermined intervals.
1.21 is erected. The tip of the rod 21.21 passes through the support device 5. A disc spring 22.22 is inserted through the portion of the rod 21.21 between the bottom of the support device 5 and the trunnion ring 4.

These rods 21.21 and disc springs 22.22 are housed inside surrounded by a heat shield plate 25.

The heat shield plate 25 has an opening 26 that takes in air at a predetermined pressure.
There are also. Furthermore, a side guide 28 is provided on the trunnion ring 4 on the outside of the support device 25 to prevent lateral displacement when the scouring furnace is tilted. In this way, the refining furnace weighing device 30 is configured.

In the case of this weighing device 30 for a refining furnace, as shown in FIG. 3(A), the weight of the empty furnace body is 800 tons, and the molten metal
Assuming 0 tons, the furnace size at one support part will be 200 tons without molten metal.

In addition, the disc springs 22 and 22 of the rod 21 are shown in Fig. 3 CB).
As shown in the figure, the tension rod 24 is urged in a compressed state with a pressing force of 150 tons, which is 50 tons added to half the furnace load per rod. Therefore, the tension rod 24
A tensile force of 100 tons, which is the sum of the spring forces at the two locations (300 tons) minus the static electricity of the furnace body, acts on the weighing scale 20, and a tensile load of 100 tons is also applied to the weighing scale 20.

Here, it is assumed that the set load of the disc springs 22 and 22 is greater than 50 tons, which is 1/4 of the amount of molten metal.

This is to prevent gaps from forming between the upper and lower surfaces of the weighing scale 20 during weighing. Here, it is set so that a tensile force of at least 50 tons is applied to each weighing scale 20 to allow for a margin.

Also, since the purpose is to understand the content, 1m! The state in which the weighing scale 20 measures a tensile force of 100 tons at the support portion at location i is set as the origin. In other words, the state in which a tensile force of 400 tons, which is the sum of the four load values, is applied is corrected to 0 tons at the origin.

Next, when 200 tons of molten metal is contained, Figure 3 (C)
As shown in the figure, 1/4 of that load, 50) tons, is applied in the direction of reducing the tensile force, so 100 tons with no load becomes 50 tons. Therefore, if you add and correct the four loads, the content ff1
You will get instructions for 200 tons.

Furthermore, when the scouring furnace is tilted, the side guides 28 prevent lateral displacement. When falling, the total spring load of the two rods 21 and 21 is 30, as shown in Figure 3 (D).
The total value of 0 tons and the furnace air ff1ti1200 tons is applied to the tension rod 24, and no gap is generated on the upper and lower surfaces of the weighing scale 20, and no impact load is applied.

In addition, since the tension rod 24.24 is cooled by the cooling fluid 27 etc., the heat generated during the scouring process is transmitted to the tension rod 24.24, causing thermal expansion and reducing the set load of the disc spring 22.22. decreases, weighing scale 20
The tensile load applied to the molten metal becomes smaller and the weight of the molten metal does not become smaller.

In this way, in this weighing device for a refining furnace, the weighing gauge 20 is provided directly on the trunnion ring 4, so that the distance between the furnace body l and the trunnion ring 4 can be sufficiently large. This makes it possible to prolong the life of the furnace body 1. For the same reason, the outer diameter of the trunnion ring 4 can be made smaller to reduce the space it occupies. Furthermore, even when the furnace body 1 falls, it is possible to avoid the generation of a gap between the upper and lower surfaces of the weighing scale 20, thereby preventing the generation of an impact load. In addition, since the tensilan rod 24.24 and the disc spring 22.22 are provided with a cooling and heat insulation mechanism, it is possible to improve the weighing accuracy. In addition, the length of the tension rod 24 to which the load is applied can be made as short as possible to reduce the thermal expansion allowance for the same temperature difference.
Weighing accuracy can be improved.

In addition, as another embodiment of the present invention, as shown in FIG.
20'' may be provided in one spring portion 32. Alternatively, as shown in FIG. 4(B), one weighing scale 20 may be provided in one spring portion 33 and Furthermore, as shown in FIG. Also good.

[Effects of the Invention] As explained above, according to the weighing device for a refining furnace according to the present invention, it is possible to avoid the impact caused by thermal expansion when the furnace body falls over, and to use the furnace body for a long time. It is possible.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing a refining furnace to which a weighing device for a refining furnace according to an embodiment of the present invention is applied, FIG. 2 is an explanatory diagram showing the configuration of a weighing device for a refining furnace according to the same embodiment, and FIG. The figures are explanatory diagrams showing the operation of the weighing device for a refining furnace according to the same embodiment, and Figs. 4 and 5.
FIG. 6 is an explanatory diagram showing a weighing device for a refining furnace according to another embodiment of the present invention, FIG. 6 is an explanatory diagram showing a refining furnace to which a conventional load cell is not applied, and FIG. FIG. 2 is an explanatory diagram showing a scouring furnace to which the method was applied and its problems. 4... Trunnion ring, 5.8... Support device, 2
0... Weighing scale, 21... Rod, 22... Belleville spring, 23... Stopper, 24... Tension rod, 2
5... Heat shield plate, 27... Coolant, 28... Side guide, 30131.34.35... Weighing device for refining furnace.

Claims (1)

[Claims] An annular body fitted to the outer periphery of the furnace body, a support device protruding from a predetermined portion of the outer periphery, a rod interposed between the support device and the annular body, and the support device A weighing device provided with an elastic member pierced through the rod between the annular bodies, and a tension rod pierced through the support device so as to receive a predetermined tensile force by utilizing the elastic action of the elastic member. 1. A weighing device for a refining furnace, comprising: a meter; and a cooling mechanism for the rod.