The use of castable refractory on the coke oven

The use of castable refractory on the coke oven

Refractory watering is a granular and powder material composed of castable refractory. It is composed of a certain amount of binding agent and moisture. It has high liquidity and is suitable for pouring. Sometimes in order to improve its liquidity or reduce its water, it can also add plasticizers or water reducing agents. Sometimes, in order to promote its condensation and hardening, it can also add a hard agent. Because its basic composition and molding, hardening process is the same as the concrete commonly used in civil engineering, it is often called this material as castable refractory.

(1) Castable refractory characteristics

The many characteristics of castable refractory depends on the variety and quantity of the binding agent, and the intensity depends on the binding strength of the binding agent.

The liquidity of castable refractory is generally higher than that of pounding. Therefore, most of the castable refractory can only be arranged and full of models in the mixed materials after only pouring or pouring. 

After the castable refractory is forming, it is necessary to adopt appropriate measures to promote hardening according to the hardening characteristics of the binding agent. For example, the cement should be maintained under proper humidity conditions; some metal inorganic salts should be dry and baked.

The high temperature properties of castable refractory are also closely related to the variety and amount of binding agents. If the granular and powder materials are selected have good fire resistance, and the melting point of the binding agent will not cause a low melting material to react with the refractory material, the castable refractory will definitely have a high fire resistance. If the material of the granular and powder materials used is certain, the fire resistance of the castable refractory is largely controlled by the combined agent. Because the castable refractory prepared by the average aluminate cement are included in the cement stone, the impact of the amount of cement on the high temperature of the castable refractory is also significant.

When the cement is used as a binding agent, during the use of high temperatures, cement stones can decompose dehydration and generate other object changes, and sintering, so that the castable refractory also change the structure while changing the volume. Due to the different temperature of the material in the cement stone, the lining made of this kind of pouring is used to form different components and structures at different distances from the working surface. Between various layers, the change of the ratio may produce internal stress or even cracks. In the sintering belt, because the granular material has been pre -burned, as the heating up only expands, the cement stones have a large number of shrinkage, and the deformation difference between the two increases, so that the combination of the cement stone and the granular material and the granular material of the cement stone and the granular material It is quite destroyed, which is very easy to crack. Not only may there be local cracks at the interface between the two, but it may even produce a sheet -like crack vertically on the working surface. When the temperature fluctuates, the stress caused by the different heat expansion rate can cause the furnace to peel off the crack at this crack. This is one of the main factors of the damage of the pouring materials made of cement due to the decomposition and dehydration of the cement stones and the formation of a layered structure.

(2) Application of castable refractory

The pouring material is currently the most widely produced and used refractory material. The king should be used to build a variety of overall structures such as the lining of various heating furnaces. For example, phosphate watering can be used for coke oven.