Construction method for tortoise-shell checks made of refractory and acid-resistant castable

Abstract

The invention discloses a tortoise-shell grid construction method of a fire-resistant and acid-resistant castable, and belongs to the technical field of castable construction methods. According to the technical scheme, in the pouring process of the fire-resistant and acid-resistant castable, the fire-resistant and acid-resistant castable is divided into blocks, the blocks are isolated through soluble formworks, after pouring is completed, the soluble formworks are gradually dissolved in water of the fire-resistant and acid-resistant castable, the fire-resistant and acid-resistant castable swells slowly, and finally expansion joints are formed in the soluble formworks. According to the method, the process of cutting the expansion joint after lining pouring, which contains potential quality hazards, is omitted, the uncontrollable quality problems of cracks and the like after the expansion joint is cut are solved, and meanwhile, the construction time and the labor cost investment are controlled by saving the process.

Description

Technical Field

[0001] The present invention relates to the technical field of the construction method of castables, and particularly relates to a construction method of a checkerboard pattern for refractory and acid-resistant castables. Background Art

[0002] In traditional lining construction methods, construction joints need to be left after pouring, and the overall construction is not carried out in blocks, increasing uncontrollable factors in pouring quality. Taking the construction method of acid-resistant castables for chimneys or heating furnaces as an example, the current construction method is as follows: First, lay the formwork for acid-resistant castables and reinforce it using the cross method. When pouring, the height of each material feeding does not exceed 200 mm. After pouring, use special tools such as vibrating rods to tamp the acid-resistant castables. After the lining pouring construction, surface treatment should be carried out: In order to prevent cracks from appearing in the castables during the natural dehydration process after pouring, a saw cut expansion joint with a thickness of 2.5 - 3 mm should be cut using a toothless saw after demolding. The size of the expansion joint is determined according to the actual construction, and the depth is preferably about 2.5 cm. If cracks appear during cutting, the cracks must be repaired. The repair method is as follows: Shovel the cracks into a small groove with a depth of 2 / 3 of the poured thickness and a width of about 50 mm, with the inside larger and the outside smaller, and repair it with castables, tamping it densely.

[0003] Therefore, the existing construction methods of refractory and acid-resistant castables have the following problems: 1) During construction, it is necessary to cut and make expansion joints after pouring, which poses potential quality hazards to the lining, and also requires a large investment in construction time and labor costs; 2) When cutting expansion joints, there are also uncontrollable quality problems such as the generation of cracks, and procedures such as repair are required, which also increases the investment in construction time and labor costs. Summary of the Invention

[0004] The technical problem to be solved by the present invention is: Overcoming the deficiencies of the prior art, providing a construction method of a checkerboard pattern for refractory and acid-resistant castables, eliminating the quality-hazardous process of cutting expansion joints after lining pouring, simultaneously solving uncontrollable quality problems such as cracks that occur after cutting expansion joints, and controlling construction time and labor cost investment by saving procedures.

[0005] The technical solution of the present invention is as follows:

[0006] In the construction method of a checkerboard pattern for refractory and acid-resistant castables, during the pouring process of the refractory and acid-resistant castables, the refractory and acid-resistant castables are divided into blocks, and soluble formwork is used to isolate between the blocks. After pouring is completed, the soluble formwork gradually dissolves in the water of the refractory and acid-resistant castables, and the refractory and acid-resistant castables slowly expand, finally forming expansion joints at the positions of the soluble formwork.

[0007] Preferably, the soluble formwork uses soluble polytetrafluoroethylene or Mikaela soluble material.

[0008] Preferably, the water content of the refractory and acid-resistant castable is ≤ 18 wt.%, and the thickness of the soluble template is 2 - 2.5 mm.

[0009] Preferably, during construction, the soluble templates are fixed to each other and to the construction operation points (such as inside the furnace, chimney, and equipment wall) by multi-point hot melting.

[0010] Preferably, during construction, the air humidity at the construction site is 25% RH ≤ air humidity ≤ 65% RH.

[0011] Preferably, during construction, the temperature at the construction site is 5°C - 32°C.

[0012] Preferably, during construction, the temperature at the construction site is 20 - 25°C.

[0013] Preferably, during block division, the size of each piece of refractory and acid-resistant castable is 300 mm × 300 mm.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] 1. The present invention uses soluble templates to replace the expansion joints in lining construction, reducing the time and input cost for cutting expansion joints after pouring, as well as the risk of cracks caused by uneven manual cutting of the subsequent lining expansion joints. This greatly reduces the possibility of cracks appearing and also reduces the manual input for crack repair.

[0016] 2. When pouring the refractory and acid-resistant castable in the present invention, the soluble templates are used to perform block construction by a fixed-size method, which well controls the construction flatness and uniformity of each piece of castable. At the same time, through the fixed-size block construction, the coincidence degree between the estimated situation of the material and the actual application situation is greatly improved, greatly reducing the material loss and waste. Detailed implementation manners

[0017] In order to enable those skilled in the art of this technology to better understand the technical solutions in the present invention, the technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention.

[0018] Example 1

[0019] In this embodiment, Kaolite 2500LID refractory castable is poured, and the specific construction process is as follows: A soluble template with a thickness of 2 mm is made of soluble polytetrafluoroethylene. Multiple soluble templates are fixed on the ground by multi-point hot melting, and the spaces enclosed by the soluble templates are arranged in a turtle-back grid pattern. Through the isolation of the soluble template, the refractory and acid-resistant castable is poured in blocks, each block having a size of 300 mm × 300 mm. If it is less than the size, it is counted as one block, and the construction is completed quickly at one time. Among them, the water content of the refractory and acid-resistant castable is 10 wt.%, the air humidity at the construction site is 40% RH, and the temperature is 25°C.

[0020] Example 2

[0021] In this embodiment, Kaolite 2500LID refractory castable is poured, and the specific construction process is as follows: A soluble template with a thickness of 2.2 mm is made of soluble polytetrafluoroethylene. Multiple soluble templates are fixed on the ground by multi-point hot melting, and the spaces enclosed by the soluble templates are arranged in a turtle-back grid pattern. Through the isolation of the soluble template, the refractory and acid-resistant castable is poured in blocks, each block having a size of 300 mm × 300 mm. If it is less than the size, it is counted as one block, and the construction is completed quickly at one time. Among them, the water content of the refractory and acid-resistant castable is 13 wt.%, the air humidity at the construction site is 50% RH, and the temperature is 22°C.

[0022] Example 3

[0023] In this embodiment, Kaolite 2500LID refractory castable is poured, and the specific construction process is as follows: A soluble template with a thickness of 2.5 mm is made of Mikaela soluble material (using the soluble template disclosed in Chinese invention patent CN113365795A). Multiple soluble templates are fixed on the ground by multi-point hot melting, and the spaces enclosed by the soluble templates are arranged in a turtle-back grid pattern. Through the isolation of the soluble template, the refractory and acid-resistant castable is poured in blocks, each block having a size of 300 mm × 300 mm. If it is less than the size, it is counted as one block, and the construction is completed quickly at one time. Among them, the water content of the refractory and acid-resistant castable is 18 wt.%, the air humidity at the construction site is 50% RH, and the temperature is 30°C.

[0024] Example 4

[0025] In this embodiment, Kaolite 2500LID refractory castable is poured, and the specific construction process is as follows: A soluble template with a thickness of 2 mm is made using Mikaela soluble material (the soluble template disclosed in Chinese invention patent CN113365795A). Multiple soluble templates are fixed on the ground by multi-point hot melting, and the spaces enclosed by the soluble templates are arranged in a turtle-back grid pattern. Through the isolation of the soluble template, the refractory and acid-resistant castable is poured in blocks, each block having a size of 300 mm × 300 mm. Those less than the size are counted as one block, and the construction is completed quickly at one time. Among them, the water content of the refractory and acid-resistant castable is 10 wt.%, the air humidity at the construction site is 45% RH, and the temperature is 32 °C.

[0026] In Examples 1-4, a soluble template is used instead of the expansion joint. After pouring is completed, the soluble template will melt when it encounters the water in the refractory and acid-resistant castable. At the same time, the refractory and acid-resistant castable will also slowly expand, and finally an expansion joint will be formed at the position of the soluble template between the blocks.

[0027] Comparative Example 1

[0028] The difference from Example 1 is that the water content of the refractory and acid-resistant castable is 22 wt.%.

[0029] In Comparative Example 1, too much water in the castable will cause two consequences: one is that the shape is not easy to fix. When the soluble template dissolves, due to too much water content, the shape of the lining material shifts and becomes loose; the other is that the soluble template continues to dissolve, and the soluble template dissolves before the lining material reaches the required strength, affecting the final construction quality and the lining strength.

[0030] Comparative Example 2

[0031] The difference from Example 2 is that the thickness of the soluble template is 3 mm. It is found that during the slow expansion of the refractory and acid-resistant castable, the refractory castable blocks are deformed. This is because the soluble template is too thick. During its dissolution process, before it is completely dissolved, the water in the lining material is released, resulting in a decrease in the volume of the lining material due to water loss, and the soluble template is not dissolved in time, resulting in deformation defects such as depressions in some positions of the lining material.

[0032] Comparative Example 3

[0033] The difference from Example 2 is that the thickness of the soluble template is 1.5 mm. It is found that during the slow expansion of the refractory and acid-resistant castable, the soluble template dissolves prematurely, resulting in the flow of the refractory and acid-resistant castable and losing its original pouring shape.

[0034] As can be seen from Example 2 and Comparative Examples 2-3, the thickness of the soluble template should be moderate, neither too thick nor too thin, so as to ensure its water solubility during the slow expansion of the refractory and acid-resistant castable, and ultimately ensure the casting quality.

[0035] Comparative Example 4

[0036] The difference from Example 3 is that during construction, the construction site was in rainy weather and the air humidity was 90% RH. It was found that the soluble template dissolved prematurely, resulting in the flow of the refractory and acid-resistant castable and the loss of its original casting shape, which was not conducive to the casting and molding of the refractory and acid-resistant castable.

[0037] Comparative Example 5

[0038] The difference from Example 4 is that during construction, the temperature at the construction site was 2°C. It was found that at this temperature, the dissolution efficiency of the soluble template was extremely low, affecting the construction efficiency.

[0039] Comparative Example 6

[0040] The difference from Example 4 is that during construction, the temperature at the construction site was 39°C. It was found that the soluble template could not be completely dissolved. This is because when the temperature at the construction site is too high, the water in the refractory and acid-resistant castable will evaporate relatively quickly, resulting in a reduction in the water used to dissolve the soluble template, and thus the soluble template cannot be completely dissolved. After the water release in the lining material ends, the volume of the lining material decreases due to water loss, and the soluble template is not dissolved in time, resulting in deformation defects such as depressions in some positions of the lining material.

Claims

1. The construction method of the checkerboard for refractory and acid-resistant castables is characterized in that, During the pouring process of the refractory and acid-resistant castable, the refractory and acid-resistant castable is divided into blocks, and soluble templates are used to isolate between the blocks. After pouring is completed, the soluble templates gradually dissolve in the water of the refractory and acid-resistant castable, and the refractory and acid-resistant castable slowly expands, finally forming expansion joints at the positions of the soluble templates.

2. The tortoise grid construction method of the refractory and acid-resistant castable according to claim 1, characterized in that, The soluble templates adopt soluble polytetrafluoroethylene or Mikaela soluble materials.

3. The construction method of the refractory and acid-resistant castable in the form of a tortoise grid as described in claim 1, characterized in that, The water content of the refractory and acid-resistant castable is ≤18 wt.%, and the thickness of the soluble templates is 2 - 2.5 mm.

4. The construction method of the refractory and acid-resistant castable in the form of a turtle grid according to claim 1, characterized in that, During construction, the soluble templates are fixed to each other and at the construction operation points by multi-point hot melting.

5. The construction method of the refractory and acid-resistant castable in the form of a turtle checkerboard according to claim 1, characterized in that, During construction, the air humidity at the construction site is 25% RH ≤ air humidity ≤ 65% RH.

6. The construction method of the refractory and acid-resistant castable in the form of a turtle grid as described in claim 1, characterized in that, During construction, the temperature at the construction site is 5°C - 32°C.

7. The construction method of the tortoise shell grid for the refractory and acid-resistant castable according to claim 6, characterized in that, During construction, the temperature at the construction site is 20 - 25°C.

8. The construction method of the refractory and acid-resistant castable in the form of a tortoise checkerboard as described in claim 1, characterized in that, When dividing into blocks, the size of each block of refractory and acid-resistant castable is 300 mm × 300 mm.