What are the damage mechanisms of cement rotary kiln kiln refractories?

      The ambient temperature at the kiln mouth of cement rotary kiln is high and fluctuates in a wide range (1000°C-1400°C): the high temperature cement clinker with a certain degree of cooling and hardening, the high temperature airflow enters the cooler through the kiln mouth, which has serious wear on the lining of the kiln mouth; the temperature at the kiln mouth changes sharply every time the cement rotary kiln starts and stops; the alkaline volatiles in the cooler and kiln are enriched in the kiln mouth part of the cycle; at the same time, the cylinder of the kiln mouth is easily deformed, which has a stress effect on the lining of the kiln mouth.

      There are four main reasons for the destruction of cement rotary kiln kiln opening castings as follows.

      1. Cement clinker and high-temperature airflow wear: cement kiln kiln mouth part of the refractory material lack of kiln skin protection, constantly by the cooling hardening of high-temperature cement clinker and high-temperature airflow scouring wear.

      2. Thermal shock damage: After the first feeding production, when cement clinker reaches the kiln mouth, it comes into direct contact with the refractory, causing its temperature to rise sharply in a short period of time, resulting in bursting or cracking of the refractory: each time the kiln is opened and stopped, the refractory at the kiln mouth is the first to receive thermal shock.

      3. Erosion of alkaline volatiles: The kiln refractory is not protected by a stable kiln skin and is subject to the erosion of cement clinker and alkaline volatiles in the secondary air.

      4. Stress damage: rotary kiln in the process of rotation will be deformed, while the kiln refractory brick will appear corresponding displacement and deformation, the kiln mouth parts of the ambient temperature changes sharply, these effects make the kiln mouth refractory material by compressive stress, tensile stress and thermal stress and other stress damage.

      The kiln opening special castable produced by ZHENJIN REFRACTORIES is a kind of high-grade refractory castable used in the kiln opening of cement kilns. As the kiln opening of cement rotary kiln is eroded by cold air, hot clinker and extremely high stress, the lining material is prone to cracking, spalling and bursting. The addition of alumina, SiC and CA cement gives the castables high thermal shock resistance, high strength and high flexibility, extending their service life.