常见滑板损毁现象及分析 Common slide gate plate damage phenomenon and analysis
Common slide gate plate damage phenomenon and analysis
1.1 Heat shock damage
The temperature of the slide gate plate is very low before use, and in the pouring process, the slide gate plate contacts with the high temperature of water steel in a short time, and the resulting huge temperature difference has a strong thermal impact on the experience of the slide gate plate . A tension stress occurs outside the slide gate plate pouring hole, and once this stress exceeds the strength of the slide gate plate material, a radial microcrack forms. Such cracks are conducive to the diffusion, aggregation and penetration of external water of molten steel, slag and oxygen, and become the inducement to aggravate chemical erosion.
1.2 Thermochemical erosion
In the use of high temperature steel and molten slag, will occur a series of chemical reactions, causing thermochemical erosion. This kind of erosion is easy to cause the slide gate plate working face high temperature and wear resistance deterioration, the surface layer falls off, resulting in poor slide gate plate anastomosis, gap increase, and then lead to inhalation, further oxidation erosion, the above process of alternating action, serious will lead to slide gate plate steel leakage and other major accidents.
1.3 Operating factors
Through practical summary, the operation factors caused by damage to the slide gate plate can be summarized into three categories: slide gate plate installation, pouring and flow control, and water inlet oxygen burning.
(1) Skate-board installation is unreasonable. When the slide gate plate is not strictly flat in the sliding mechanism, warping, or the slide gate plate clamp loose, will produce great external stress in the process of use, leading to the overall damage of the slide gate plate .
(2) Unreasonable pouring and flow control in production. When the flow control operation is unreasonable in the pouring process, it is easy to lead to the flaking, erosion and steel clip of the slide gate plate working face. Summarize the flow control operation in the production, it is found that the main reason that can easily cause slide gate plate damage is that the slide gate plate action range is too large, or too frequent action, especially the number of slide gate plate damage caused by manual flow control is more than the computer automatic flow control, indicating that the human factors in the operation are also an important cause of slide gate plate damage.
(3) Oxyburning operation is unreasonable. When the steel package preparation operation or does not flow during the pouring process, the steel package water outlet should be burned for oxygen. Once the oxygen burning operation is improper, it will produce serious oxygen erosion. Improper oxygen burning operation causing slide gate plate damage includes: the slide gate plate does not blow oxygen completely eye to eye, causing oxygen to directly impact the slide gate plate working face, it is difficult to burn oxygen, causing too long oxygen blowing time; the oxygen pipe is not parallel to the flow channel, causing oxygen flow to wash the edge wall of the slide gate plate hole, forming hole expansion. In addition, other improper operation factors include the unreasonable turnover time, resulting in the overall temperature drop, the heat impact; improper ratio of slide gate plate mud, uneven mixing, impurities, etc.