Autoclaved aerated concrete block is a new type of wall material that can effectively achieve self insulation function, has a wide range of raw material sources, good fire resistance, and high production efficiency. Autoclaved aerated concrete blocks are widely used in the interior and exterior wall engineering of various industrial and civil buildings. Due to the fact that autoclaved aerated concrete blocks can utilize a large amount of industrial solid waste such as fly ash, with a waste residue content exceeding 70%, they enjoy preferential policies of full exemption from enterprise value-added tax and income tax. Autoclaved aerated concrete blocks are rapidly developing nationwide. Autoclaved aerated concrete blocks have become the leading product with the largest usage in new wall materials.
The aerated concrete equipment used for producing blocks requires various raw materials, and each raw material can be used for different varieties. The use of raw materials in factory production mainly depends on local resources, the products produced, and the factory's production, technology, and equipment conditions.
According to the basic functions of various raw materials in the production process of aerated concrete equipment, they can be divided into four categories. Namely: basic component materials, gas generating materials, conditioning materials, and structural materials. 1. The basic component materials are siliceous materials and calcareous materials; Gas generating materials refer to gas generating agents and bubble stabilizers; Adjusting materials includes gas generation process regulators and high-pressure sterilization process regulators; The structural materials include steel bars and steel corrosion inhibitors.
In the production process of aerated concrete equipment, different auxiliary materials can also be used according to the process requirements and specific conditions of each production equipment.
In the static hardening process of aerated concrete block blanks, the hardening effect is different from the non insulation effect. If the temperature of the billet quickly disappears, for example, if there is no insulation in winter in the north, the billet will not only be greatly affected by the hardening speed, but also severely shrink and sink. Therefore, currently, all factories tend to use insulation and stopping facilities to ensure the solidification speed and uniformity of the billet.
The cutting machine used in aerated concrete equipment mainly divides and visualizes the aerated concrete body to meet the shape requirements of aerated concrete products. The cutting process reflects the characteristics of aerated concrete, which is easy to form in large volume, easy to separate, flexible in appearance, can meet different application needs, and can be mechanized on a large scale. It is also a type of aerated concrete that is different from other types of concrete.
In the process of selecting and using raw materials, it is necessary to fully grasp the fundamental role of the entire raw material. Its main sand provides the entire siliceous material, rather than reacting with calcium in calcareous materials to generate hydration products, which contribute to the strength of the entire product. Raw sand can also serve as a skeleton, and the overall raw material needs to reduce the shrinkage mechanism of the entire concrete. Next is quicklime, which needs to provide effective calcium oxide and be able to react with silica in the siliceous material of the material to generate significant hydration products, resulting in the strength of the entire product. Lime can also provide alkalinity, causing it to gasify with aluminum powder paste. The hydration of lime requires physical heat release to promote the hardening of the entire body. And cement requires the provision of calcium materials to contribute to the strength of sand aerated concrete. The main function of cement is to ensure the stability of the castability of the entire material.
Accelerate the hardening of the entire mold and the strength of the entire mold plasticity during cutting. Once again, gypsum contributes to the strength of the entire body. Due to the natural generation of hydrated calcium sulphoaluminate and the gel of the whole material during the static stop of the whole material, the bearing capacity of the temperature difference stress and humidity difference stress naturally occurring in the autoclave process of the whole material blank is constantly enhanced. It can also quickly improve the strength of the entire product, reduce the shrinkage of the entire material, and enhance the frost resistance of the entire product. The speed of the natural fuel hydration reaction of the entire material promotes the transformation of the entire tobermore to form strength.
And the generation of water pomegranate seeds in the entire material continuously reduces the shrinkage value of the entire material. It can also slow down the thickening speed of the slurry, slow down the setting speed of the entire cement, and dissolve the entire lime to quickly reduce its solubility. The temperature of the entire material also needs to be lowered as soon as possible.
It can also alleviate the thickening speed of the slurry, slow down the setting speed of the entire cement, and reduce the solubility of lime by dissolving it. The temperature of the entire material also needs to be quickly reduced by dissolving it. This is the summary process of the basic role of raw materials for aerated block equipment.
Due to the fact that autoclaved aerated concrete blocks are non load bearing products that mainly serve as infill walls and do not affect the safety of the entire construction project, their quality is generally overlooked. Moreover, in many regions, there is a shortage of supply for autoclaved aerated concrete blocks. Many production enterprises, tempted by profits, pursue rapid production and high output in order to reduce costs, arbitrarily shorten the maintenance cycle, and use low investment to eliminate outdated production equipment and processes, resulting in extremely unstable product quality and high product failure rate of aerated concrete blocks. In 2013, the Quality and Technical Supervision Bureau of Guizhou Province conducted a supervision and spot check on the product quality of autoclaved aerated concrete block production enterprises in the province. A total of 40 batches of samples from 40 enterprises were sampled, and only 25 batches were qualified. The comprehensive batch qualification rate was only 62.5%. In 2014, the Quality and Technical Supervision Bureau of Guizhou Province conducted another supervision and spot check on the product quality of autoclaved aerated concrete block production enterprises in the province. A total of 47 batches of samples from 47 enterprises were sampled, and 37 batches were qualified. The comprehensive batch qualification rate was only 78.7%. As one of the most widely used new wall materials, the quality of autoclaved aerated concrete products affects the entire new wall material industry and downstream construction industry. It is necessary to improve the production quality of autoclaved aerated concrete blocks.
The most effective method to improve the production quality of autoclaved aerated concrete blocks is to use advanced technology and equipment. For most normal production enterprises, the process and equipment are already fixed. If improvements are made, it requires a significant investment and is constrained by various factors such as the site. This is more suitable for newly established enterprises. The most feasible way for enterprises with normal production to improve quality is to strengthen production quality management and enhance the level of production quality management.
Autoclaved aerated concrete blocks are a widely used new type of wall material, and production enterprises should pay attention to product quality. Improving quality management can not only enhance product quality, but also reduce production costs and increase economic benefits for enterprises.
