- Time:Jun 02, 2022
The lining of the kiln is selected according to the operating conditions, and the refractory bricks for lining masonry should be selected according to a number of indicators. What factors determine the quality of the refractory bricks and how to judge?
How to choose the furnace lining? The industrial furnace needs to be lined with refractory materials to escort its operation. In order to ensure that the lining refractories can better serve various types of kiln equipment, a series of optimized configurations have been carried out to prolong the service life of the kiln. The refractory material is an important basis for the design of the lining structure, and the quality of the lining refractory material is directly related to whether the whole project can be put into production smoothly. Therefore, it is particularly important to combine the performance of lining refractories and related process design. That is to say, it requires a complete process and a reasonable configuration of materials. High-performance refractory lined refractory materials will inevitably be affected by changes in ambient temperature during use, such as: oven, temperature rise, temperature changes during operation, steam purging, temperature rise and fall, etc. The operation is stable, avoiding the damage to the lining caused by rapid cooling and rapid heating, and improving the thermal stability of the material, which is beneficial to prolong the service life of the lining. The liner is used in a high temperature environment, so that it is thermally expanded under high temperature conditions, so that it is squeezed to generate thermal stress. If the internal stress of the lining exceeds its own strength, spalling failure, etc. will occur. Due to the special and harsh conditions of use, the performance requirements for lining refractories are also getting higher and higher. Construction charges mainly include general building materials such as refractory materials, heat insulating refractory materials, steel, wood, cement and other auxiliary materials.
Grasping the variety, specifications and performance of various furnace building materials, reasonably selecting and using various refractory materials, strengthening the scientific management of refractory materials, and reducing the loss of materials are the main factors to ensure the quality of industrial furnace masonry engineering and improve the service life of furnace The premise is that the general principles for selecting refractory materials for furnace construction: (1) The refractory materials must have technical properties that can meet the requirements of industrial furnaces, and their performance indicators should meet the current standard regulations or design requirements. (2) The selected refractory materials must have good construction performance and meet the construction technical requirements and engineering quality requirements. (3) The refractory materials used must comply with the laws, regulations and technical specifications on labor protection and environmental protection. The quality of the refractory material determines the service life of the kiln lining and the quality of the bricks. How to judge? Judging the quality of refractory bricks by seeing color and black spots. From the process of material selection, batching, molding, drying, firing, cooling, etc., the personnel involved in the production process are relatively fluid. Even if the operating specifications are formulated, in the fully automated production process, the color of the refractory bricks will also vary. different.
The firing temperature of various refractory bricks is different. It is impossible for the whole kiln to fire the same product. The requirements for production and preparation often include refractory bricks with other indicators, which leads to some refractory bricks under-fired or the firing temperature is too high. When a certain temperature is reached during high temperature use, the color will return to normal. All refractory bricks have a certain degree of high temperature expansion or contraction, and products with too high firing temperatures eliminate this problem and ensure the air tightness of the blocks in use. In this way, it can be seen that the difference in the color of different refractory bricks negates the quality of the refractory bricks. A single index judges the quality of refractory bricks. Refractory bricks are a kind of inorganic non-metallic materials whose refractory temperature is not lower than 1580℃. They are mixed according to a certain scientific ratio. The factors of change are physical and chemical changes of stability. Different types of refractory bricks, such as clay bricks, high-alumina bricks, mullite bricks, lightweight insulation bricks, etc., each manufacturer has its own physical and chemical index specifications. This single index should be the main material content, refractory temperature, etc. The quality of refractory bricks cannot be denied because a certain index does not meet the index requirements, and the comprehensive performance of the product should be considered under the conditions of meeting the production environment. The quality of the refractory brick is judged by the weight of the refractory brick. All refractory bricks have specifications and dimensions, have bulk density, and can calculate their unit weight. In the fierce competition in the market, the editor also heard some rumors about "fake goods". Firebricks fired at high temperature do not contain moisture. In order to achieve the temptation of selling huge profits, some traders pour water into low-grade refractory bricks, creating the illusion that the single weight meets the standard. High temperature fired refractory bricks can distinguish between moisture content and moisture content. Sampling and weighing, firing at high temperature for a certain period of time, and cooling after cooling, the difference in weight before and after is the weight of water, the weight does not change much, and the weight does not change. It can be seen that the high purchaser of refractory bricks is the direct purchase of manufacturers, and they can buy genuine products under the condition of quality, reputation, and after-sales guarantees. The misunderstanding of judging the quality of refractory bricks by price: the emphasis here is on the price of refractory bricks under the condition that the physical and chemical indicators meet the needs of users, rather than determining the price by reducing the standard of user needs. Especially for dealers, the quotation is often lower than the manufacturer's quotation. Why? Not much to say here. It can be said that it is better to trust the manufacturer's offer. The price of fire bricks depends on factors such as index content and production cost. When the technical indicators are up to the standard, good products are not necessarily expensive. Therefore, it is unreasonable to only determine the quality of a certain brick based on the price.
Therefore, when using refractory bricks, it is very important to master these points, so that the practical application of refractory bricks can be better carried out.