Each process link in the production of magnesia carbon bricks must be strictly monitored. Among them, mixing, forming, and drying are particularly important in the production.
1. Break and smash
Crushing is the process of processing large pieces of material into ideal particle size materials. It is an indispensable process in the production of refractory materials. Although simple, it is very important. It has an important influence on the stability of product quality. At the same time, the crushing equipment has high power consumption, high wear and high maintenance rate, so the maintenance cost is high. Pay attention to crushing, stabilize product quality, save energy and reduce consumption.
2. Ingredients (weighing)
Ingredients are the process of combining different raw materials and different particles according to product formula design. The method of ingredients varies according to the type and state of the raw materials.
The heavy star batching method is usually used in the production of magnesia carbon bricks, because the weight batching method has high accuracy, generally not exceeding 2%. Commonly used weight batching equipment includes manual weighing scales, automatic weighing scales, weighing carts, etc. The corresponding equipment is selected according to requirements and automatic control levels.
3. Preparation of mud (mixing, kneading)
The purpose of mixing is to make the composition of the materials uniform and maximize the contact surface between different materials. The mixing of refractory materials is a method to homogenize the materials with the process of extrusion, kneading and exhaust. Like the mixing of any powder, the mixing of refractory materials is carried out gradually, and the mixing process is more complicated due to the composition, particle size, binder and admixture of the materials.
Forming is an indispensable process for the production of shaped refractory products. It is a process in which refractory mud becomes a body with a certain shape and strength under the combined action of pressurizing equipment and molds.
Refractories have a variety of molding methods, using semi-dry compression molding. Semi-dry molding has less stringent requirements for the mud, and the process is simple. During the pressurization process, due to the low moisture content of the mud, large pressure must be used to force the particles to be tightly combined. Under the action of external force, the particles are rearranged, the gas is discharged, the particles are combined and then produce strength, forming a green body with a certain shape. The most important factor in semi-dry molding is the external pressure. Within a certain pressure range, the external pressure directly determines the performance of the magnesia carbon brick. As the pressure increases, the density of the green body increases, the porosity decreases, and the strength increases.
5. Heat treatment (drying)
The heat treatment temperature of magnesia carbon brick has a direct influence on its performance. The heat treatment process is actually the curing process of the phenolic resin. The heat treatment temperature and heat treatment time directly determine whether the phenolic resin is completely cured. Within a certain range, the time for the resin to completely cure is inversely proportional to the curing temperature, but not a linear relationship.