阅读说明：本技术 一种金属液熔炼炉炉衬的在线修补方法 (On-line repairing method for furnace lining of molten metal smelting furnace ) 是由 杜永冠 李轩轩 于 2021-08-02 设计创作，主要内容包括：本发明涉及铸造工艺的技术领域,公开了一种金属液熔炼炉炉衬的在线修补方法,根据炉衬各部位因灼伤程度不同而出现厚度不均的情况,通过往熔炼炉内投进体积略小于原有坩埚的修补埚体,并采用耐火砂完全填充新旧坩埚之间的空隙,针对性地对受损的炉衬进行在线修复,使得炉衬得以继续使用,防止漏炉现象,进而实现炉衬乃至整个熔炼炉使用寿命的提升,一定程度上维护了铸造工艺的生产效率。(The invention relates to the technical field of casting technology, and discloses an online repairing method of a furnace lining of a molten metal smelting furnace.)

1. A method of on-line repairing a lining of a molten metal smelting furnace, the smelting furnace including a lining and a crucible nested within the lining, the method being adapted for use in the event that the lining and the crucible are damaged and thinned, the method including the steps of:

(1) emptying molten metal in the smelting furnace, and cooling the wall body of the smelting furnace to below 40 ℃;

(2) cleaning the residual metal sticky slag in the smelting furnace;

(3) uniformly injecting a high-temperature-resistant filling agent into the bottom of the smelting furnace, wherein the high-temperature-resistant filling agent completely covers the bottom wall of the smelting furnace;

(4) putting a repairing crucible body into the smelting furnace from top to bottom until the repairing crucible body is abutted with the high-temperature-resistant filler paved at the bottom of the smelting furnace;

(5) filling the high-temperature-resistant filler between the side wall of the repaired crucible body and the side wall of the furnace lining;

(6) and (4) completely covering the top end of the high-temperature-resistant filler in the step (5) by using an adhesive to isolate the high-temperature-resistant filler from contacting with the outside.

2. The on-line repairing method of a lining of a molten metal melting furnace according to claim 1, wherein an outer diameter of the repairing body is slightly smaller than an inner diameter of the crucible, and a height of the repairing body is smaller than a height of the crucible.

3. The on-line repairing method of a lining of a molten metal smelting furnace according to claim 2, wherein a bevel edge is provided at a corner of the bottom of the repairing body, the bevel edge being inclined upward at 45 degrees from the bottom wall to the side wall of the repairing body.

4. The on-line repairing method for the lining of the molten metal smelting furnace according to claim 3, wherein the material of the repairing body comprises but is not limited to graphite, quartz, cast iron and refractory clay.

5. The method for online repairing of a lining of a molten metal melting furnace according to claim 1, wherein in the step (3), the refractory filler is repeatedly pulled out and inserted by using an insertion bar to discharge excess air.

6. The method for online repairing of a lining of a molten metal melting furnace according to claim 4, wherein in the step (3), after the insertion of the insertion bar, the inner bottom wall of the melting furnace is vibrated by a high frequency vibrator to promote the uniform laying of the high temperature resistant filler.

7. The method of on-line repairing a lining of a molten metal melting furnace according to claim 5, wherein in the step (5), the refractory filler is poured in a batch-wise manner, and after each batch of the refractory filler is poured, the refractory filler is repeatedly pulled out and inserted by the use of the insert until the refractory filler is filled to discharge air and prevent generation of pores.

8. The method for online repairing a furnace lining of a molten metal melting furnace according to claim 6, wherein in the step (5), after the high-temperature-resistant filler is filled, the inner wall of the repaired body is vibrated from top to bottom by the high-frequency vibrator.

9. The on-line repairing method for the lining of the molten metal smelting furnace according to claim 1, wherein in the step (6), the adhesive is arranged in the form of a slope, the slope gradually inclines upwards from the top end of the repaired body to the inner wall of the lining, and the angle of the slope is 30-45 degrees.

10. The method for on-line repairing of a lining of a molten metal smelting furnace according to claim 1, wherein the high-temperature-resistant filler is refractory sand, and the adhesive is refractory mortar.

Technical Field

The invention belongs to the technical field of casting processes, and particularly relates to an online repairing method for a furnace lining of a molten metal smelting furnace.

Background

In the casting process, molten metal is an indispensable key link, the smelting process is realized by means of a smelting furnace, as shown in fig. 1, the smelting furnace comprises a crucible, the outer wall and the bottom of the crucible are wrapped by a furnace lining, the outer wall of the furnace lining is wrapped by refractory mortar, the scouring amplitude of the position of the low liquid level in the smelting process is larger, therefore, the lower part of the crucible is easy to corrode and damage along with the increase of the furnace life, after the crucible is damaged and sintered, the molten metal further permeates to generate burning damage to the furnace lining, the furnace leakage phenomenon is caused, and the specific furnace bottom wear thinning condition is as shown in fig. 2.

For the furnace leakage phenomenon, field personnel need to take corresponding measures to repair defects of the furnace wall, but because the crucible and the furnace lining are sintered and damaged and are difficult to separate and replace, the conventional method is to smash the damaged smelting furnace and then build the furnace again. According to the production scale of the current casting industry, at least 3 working days are required for building a conventional new furnace, and a plurality of tons of furnace lining materials are used, and a large amount of lining waste is generated.

Therefore, the furnace wall damage has great influence on the smelting furnace, and a process method capable of quickly repairing the furnace wall needs to be developed aiming at the situation, so that the service life of the smelting furnace is prolonged, and the resource waste is reduced.

Disclosure of Invention

Aiming at the problems in the prior art, the invention aims to provide an on-line repairing method of a furnace lining of a molten metal smelting furnace, which aims at repairing the damaged part of the furnace wall and prolonging the service life of the furnace lining so as to prolong the service life of the smelting furnace.

The above object of the present invention is achieved by the following technical solutions:

a method of on-line repairing a lining of a molten metal smelting furnace, the smelting furnace including a lining and a crucible nested within the lining, the method being suitable for use in the event that the lining and crucible are damaged and thinned, the method including the steps of:

(1) emptying molten metal in the smelting furnace, and cooling the wall body of the smelting furnace to below 40 ℃;

(2) cleaning the residual metal sticky slag in the smelting furnace;

(3) uniformly injecting a high-temperature-resistant filling agent into the bottom of the smelting furnace, wherein the high-temperature-resistant filling agent completely covers the bottom wall of the smelting furnace;

(4) putting a repairing crucible body into the smelting furnace from top to bottom until the repairing crucible body is abutted with the high-temperature-resistant filler paved at the bottom of the smelting furnace;

(5) filling the high-temperature-resistant filler between the side wall of the repaired crucible body and the side wall of the furnace lining;

(6) and (4) completely covering the top end of the high-temperature-resistant filler in the step (5) by using an adhesive to isolate the high-temperature-resistant filler from contacting with the outside.

Preferably, the external diameter of the repair body is slightly smaller than the internal diameter of the crucible, and the height of the repair body is smaller than the height of the crucible.

Preferably, a bevel edge is provided at a corner of the bottom of the repair body, the bevel edge being inclined upward at 45 degrees from the bottom wall to the side wall of the repair body.

Preferably, the material of the repair crucible body includes, but is not limited to, graphite, quartz, cast iron, and chamotte.

Preferably, in the step (3), the high temperature-resistant filler is repeatedly pulled out and inserted by using a slip to discharge excess air.

Preferably, in the step (3), after the cutting is pulled and inserted, a high-frequency vibrator is adopted to vibrate the inner bottom wall of the smelting furnace, so as to promote the high-temperature-resistant filler to be uniformly laid.

Preferably, in the step (5), the refractory filler is sequentially filled in batches, and after each batch of the refractory filler is filled, the refractory filler is repeatedly pulled out and inserted by using the insert strip to discharge air, thereby preventing generation of pores until the refractory filler is filled.

Preferably, in the step (5), after the high-temperature-resistant filler is filled, the inner wall of the repaired crucible body is vibrated from top to bottom by using the high-frequency vibrator.

Preferably, in the step (6), the adhesive is arranged in a slope form, and gradually inclines upwards from the top end of the repaired crucible body to the inner wall of the furnace lining, and the angle of the slope is 30-45 degrees.

Preferably, the high-temperature-resistant filler is refractory sand, and the adhesive is refractory mortar.

Compared with the prior art, the invention has the beneficial effects that:

according to the condition that the thicknesses of all parts of the furnace lining are uneven due to different burning degrees, by adopting the technical scheme of the invention, the damaged furnace lining is repaired on line in a targeted manner by throwing the repairing crucible body with the volume slightly smaller than that of the original crucible into the smelting furnace and completely filling gaps between the new crucible and the old crucible with refractory sand, so that the furnace lining can be continuously used, the phenomenon of furnace leakage is prevented, the service life of the furnace lining and even the whole smelting furnace is prolonged, and the production efficiency of the casting process is maintained to a certain extent.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

Fig. 1 is a schematic structural view of a conventional melting furnace in a sound state;

FIG. 2 is a schematic view showing a structure of a conventional melting furnace when a lower portion thereof is damaged;

FIG. 3 is a schematic structural view of a melting furnace repaired by the method of the present embodiment;

FIG. 4 is a schematic view of the repair of the body according to the present example;

FIG. 5 is a graph showing the trend of the lining thickness change of the melting furnace before and after repair (furnace repair at 240);

FIG. 6 is a comparison of furnace life before and after repair;

in the figure, 1-furnace lining; 2-a crucible; 3-high temperature resistant filler; 4-repairing the crucible body; 5-adhesive; 6-lifting lugs; 7-beveled edge.

Detailed Description

The following further describes embodiments of the present invention with reference to the drawings. It should be noted that the description of the embodiments is provided to help understanding of the present invention, but the present invention is not limited thereto. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

The embodiment provides an on-line repairing method for a lining of a molten metal smelting furnace, as shown in fig. 2, the smelting furnace comprises a lining 1 and a crucible 2 nested in the lining 1, and the method comprises the following steps for the case that the lining 1 and the crucible 2 are damaged and thinned:

(1) discharging molten iron, emptying molten metal in the smelting furnace, and cooling the wall body of the smelting furnace to below 40 ℃ in a standing or air blowing mode to provide operating conditions for the subsequent fettling procedure;

(2) cleaning residual metal sticky slag in the smelting furnace by using tools such as a file and the like;

(3) uniformly injecting high-temperature-resistant filler 3 with enough thickness into the bottom of the smelting furnace, wherein the high-temperature-resistant filler 3 is enough to completely cover the bottom wall of the smelting furnace;

(4) as shown in fig. 3, the repairing crucible body 4 is put into the melting furnace from top to bottom by means of a hoisting mechanism until the repairing crucible body 4 is compacted on the high-temperature-resistant filler 3 at the bottom of the melting furnace;

(5) a gap is formed between the outer side wall of the repairing crucible body 4 and the inner side wall of the furnace lining 1, the gap is filled with the high-temperature-resistant filler 3, the high-temperature-resistant filler 3 is used for filling the space between the repairing crucible body 4 and the furnace lining 1, the residual burnt and damaged part of the furnace wall is completely repaired, the position of the repairing crucible body 4 can be fixed, and the repairing crucible body 4 is prevented from shaking in the smelting process to tear the inner wall of the furnace lining 1, so that secondary damage is caused;

(6) after the high-temperature-resistant filler 3 is filled, the top end of the high-temperature-resistant filler 3 is covered by an adhesive 5 to isolate the high-temperature-resistant filler 3 from contacting with the outside, so that the repairing crucible body 4 and the furnace lining 1 are integrated into a whole, and the repairing crucible body 4 replaces the damaged part of the crucible 2 to play a role in containing metal liquid.

Referring to fig. 4, the top of the repairing crucible body 4 is open and has a shape similar to that of the crucible 2, in order to smoothly enter the smelting furnace, the outer diameter of the repairing crucible body 4 is set to be slightly smaller than the inner diameter of the crucible 2, the repairing crucible body 4 should not exceed the height of the crucible 2, and the specific height of the repairing crucible body 4 is determined according to the actual crucible burn situation, and should be based on covering the burn part, so as to completely repair the inner wall of the furnace lining 1.

Further, the top end of the repairing crucible body 4 is symmetrically provided with more than two lifting lugs 6, and the lifting mechanism drives the lifting of the repairing crucible body 4 through hooking the lifting lugs 6.

Further, the joint of the bottom wall and the side wall of the repaired crucible body 4 is provided with a bevel edge 7, and the bevel edge 7 gradually inclines upwards from the inside of the crucible to the outside of the crucible to form a 45-degree chamfer angle.

Specifically, the material of the repair crucible body 4 includes, but is not limited to, graphite, quartz, cast iron, chamotte, and the like, which are commonly used for refractory crucibles.

In the step (3), the high-temperature-resistant filler 3 is injected in batches, and after each charging, the high-temperature-resistant filler 3 needs to be repeatedly pulled out and inserted by using a cutting (not shown in the figure) to discharge redundant air, so that the generation of air holes is prevented; after the cutting is pulled out and inserted, the inner bottom wall of the smelting furnace is preferably vibrated by a high-frequency vibrator (not shown in the figure) until the high-temperature-resistant filler 3 is uniformly laid.

Similarly, in the step (5), the high temperature resistant filler 3 is filled in batches, and after each filling, the high temperature resistant filler 3 needs to be repeatedly pulled out and inserted by using the inserting strip to exhaust air until the high temperature resistant filler 3 is filled; after the high-temperature-resistant filler 3 is filled, the inner wall of the repairing crucible body 4 is preferably vibrated from top to bottom by the high-frequency vibrator, and in order to ensure that the high-temperature-resistant filler 3 is sufficiently broken up to form sufficient compactness, the time of single vibration is not less than 6 minutes.

According to the technical scheme, the high-temperature-resistant filler 3 is added in batches and gradually, and the cutting and the high-frequency vibrator are used for repeatedly exhausting and vibrating the filler for multiple times, so that the texture of the high-temperature-resistant filler 3 is more exquisite and uniform, and the compact filling effect is achieved. Specifically, the high-frequency vibrator proposes a pneumatic piston vibrator which can generate uniform directional force and effectively overcome the internal friction force and the gathering force of materials through rapid alternating speed and acceleration so as to eliminate the relative stability among the materials and have strong anti-blocking capability.

Referring to fig. 3, in the present embodiment, in the step (6), the adhesive 5 completely covers the region from the top end edge of the repairing crucible body 4 to the inner wall of the furnace lining 1, and the high temperature-resistant filler 3 completely covers the gap between the side edges to prevent the leakage thereof, and it should be noted that the adhesive 5 is arranged in a form of a slope, and the slope gradually inclines upward from the top end of the repairing crucible body 4 to the inner wall of the furnace lining 1, and the angle of the slope is 30 to 45 degrees. The reason is that the inner diameter of the repairing crucible body 4 is smaller than that of the crucible 2, so that the top edge of the repairing crucible body 4 protrudes in the furnace after being placed, and a downward slope is formed at the top edge by using the adhesive 5, so that molten metal can flow downward, flushing collision on the top of the repairing crucible body 4 is reduced, and the surface quality of the furnace wall after being repaired is ensured to a certain extent.

In this embodiment, the high-temperature-resistant filler 3 is refractory sand, and the adhesive 5 is refractory mortar.

In order to demonstrate the repairing effect of the technical scheme of the invention on the inner wall of the melting furnace, the embodiment of the invention utilizes the method to reform the melting furnace which is seriously burnt at the bottom of the crucible and harms the furnace lining body, and the method specifically comprises the following steps:

the shape of the smelting furnace is shown in figure 1, the thickness of the furnace lining at the A position and the B position is 115mm, and the thickness at the C position is 180 mm; after 240 furnaces, as shown in FIG. 2, the thickness of the furnace lining at A and B is still kept at 115mm, the thickness at C is corroded and thinned to 92mm, and according to the wear rate, the smelting furnace is completely scrapped at 291 furnaces according to the empirical estimation;

in the embodiment, a repaired crucible body with a corresponding size is provided, the furnace wall is repaired by using the method of the invention, so that the thickness of the lower part of the smelting furnace is recovered to 180mm, and the smelting process is continued, and as a result, the repaired lower part of the furnace lining is still subjected to scouring of molten metal and is burned and thinned, but the furnace is not scrapped until 501, and the furnace life is increased by more than 70% compared with the state before repair, and specific data refer to fig. 5 and 6.

Therefore, the combination of the test results shows that the method provided by the invention can be used for specifically repairing the inner wall of the smelting furnace, so that the service life of the smelting furnace can be effectively prolonged, and the production efficiency of the casting process is maintained to a certain extent.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the described embodiments. It will be apparent to those skilled in the art that various changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, and the scope of protection is still within the scope of the invention.