Practical research and damage analysis of blast furnace iron trench
Cause Analysis of Blast Furnace Iron Ditch Damage
Intermittent tapping brings rapid temperature changes, and the rapid rise in temperature during the first tapping causes material cracking and peeling. For example, the blast furnace has two tapping holes in the north and south, each tapping 5-7 times a day, and each tapping time is 1 ~ 2h. From a high temperature of about 1350 ° C to normal temperature, repeated thermal cycles cause internal thermal stress to increase. When the internal thermal stress is greater than the stress that the iron gutter itself can withstand, the iron gutter is destroyed, thereby affecting the iron gutter. Service life.
In order to reduce the temperature of the iron ditch in a short time, it is the only option to cool the iron ditch with water after the iron is tapped. However, fetching water has accelerated the cracking, loosening, flaking and damage of refractory materials
Improvement of baking-free ramming material in blast furnace iron ditch
There is a serious problem of slag sticking during the use of iron gutter (especially the large amount of blast furnace slag, which is more likely to stick to slag), and it is easy to damage the iron gutter during slag removal. In order to solve the problem of sticky slag in iron ditch materials, it is necessary to adjust the baking-free ramming material for the iron ditch. The former needs to add a burning accelerator to the ramming material; the latter hopes that the contact interface between the ramming material and the slag forms a liquid phase film at the tapping temperature, so that a large amount of slag is avoided. Adhering to the surface of the ramming material, both the anti-slagging agent and the scorch promoter need to be low melting materials. However, the addition of low melting materials will cause the high temperature performance of the ramming material to change, especially the reduction of slag resistance.