The core competitiveness of alumina-rich sillimanite bricks lies in their uniform and dense microstructure and stable physical and chemical properties. The density and density uniformity of the green body are entirely dependent on precise control during the forming stage - the forming process must meet four core requirements: uniform density, dense structure, no cracks, and intact edges and corners. It is necessary to ensure uniform density throughout the green body, with a finished product volume density controlled between 2.6-2.8g/cm³ and an apparent porosity of ≤13%, laying a solid foundation for subsequent high-temperature sintering. At the same time, it is necessary to avoid the agglomeration of alumina-rich sillimanite crystals and the stratification of raw materials during the pressurization process to prevent structural porosity, crack propagation, and spalling after sintering. Additionally, the pressurization speed and holding time must be precisely controlled to accommodate the complex particle size distribution, difficult air exhaust, and poor fluidity of the alumina-rich sillimanite mixture, avoiding residual pores within the green body that could lead to erosion and penetration, as well as structural failure during high-temperature service. Currently, the technical shortcomings of traditional forming equipment have led to widespread issues in the production of alumina-rich sillimanite bricks, such as uneven density, green body cracking, edge and corner damage, large dimensional deviations, and low product qualification rates, severely restricting the industrial development of high-end alumina-rich sillimanite bricks. Zhengzhou Haloong, relying on the third-generation permanent magnet synchronous servo direct drive core technology, has upgraded the HLDS series of CNC servo screw presses, specifically addressing the forming challenges of alumina-rich sillimanite bricks and creating dedicated forming equipment. With the core advantages of precise pressure control, flexible pressure transmission, and intelligent adaptability, it has established a benchmark for high-end alumina-rich sillimanite brick quality.

Compared to ordinary refractory bricks, the forming difficulty of alumina-rich sillimanite bricks is significantly increased due to the characteristics of the raw materials and performance requirements. The mixture is composed of coarse and fine alumina-rich sillimanite powder, along with alumina and sillimanite additives in precise proportions. The particle size distribution is wide, the fluidity is poor, and air exhaust is difficult. Moreover, the alumina-rich sillimanite crystals are hard and brittle, making it easy for crystal agglomeration, green body micro-cracks, and edge and corner damage to occur during the forming process. The precision requirements for the application force, pressurization speed, and holding time are extremely strict - it is necessary to achieve green body densification through precise pressurization, ensuring the uniform dispersion of alumina-rich sillimanite crystals, while avoiding green body cracking and edge and corner damage caused by rigid impact. At the same time, it is necessary to efficiently remove air from the mixture to prevent residual pores from affecting the product's thermal shock resistance and erosion resistance.

Zhengzhou Haloong has deeply studied the raw material characteristics, forming process logic, and industry upgrade demands of alumina-rich sillimanite bricks. With the core technology of permanent magnet synchronous servo motor direct drive + static pressure flexible pressure transmission + intelligent CNC system, it has specifically optimized the HLDS series of servo screw presses. The equipment's precision, stability, and adaptability have been comprehensively upgraded, with advantages precisely matching the forming requirements of alumina-rich sillimanite bricks. It has become the preferred equipment for mass production of high-quality alumina-rich sillimanite bricks, assisting refractory material enterprises in creating high-quality products suitable for high-temperature, strong thermal shock, and strong erosion working conditions.

Equipped with a core permanent magnet synchronous servo motor direct drive system, it has completely eliminated the inefficient transmission structures such as traditional friction discs and clutches, with an extremely short transmission chain and zero energy loss during energy transmission. The pressure output is fully stable and controllable throughout the process. The equipment is equipped with Haloong's independently developed CNC pressure control module for alumina-rich sillimanite bricks, which can digitally and precisely set the impact energy, pressurization speed, stepwise pressurization times, and holding time. The energy repetition control accuracy is ≤±1%, ensuring that the pressure for each forming process is highly consistent, completely eliminating quality deviations caused by manual operation and mechanical fluctuations. In response to the complex particle size distribution, difficult exhaust, and easy agglomeration of the aluminous sillimanite mixture, a customized stepwise flexible pressurization process was developed. This process first lightly presses the raw materials to slowly expel the internal residual air, then gradually applies pressure layer by layer, and finally maintains the pressure for a long time to shape the product. This ensures that all parts of the green body, including the center, edges, and corners, are uniformly stressed, with the density fluctuation controlled within a very small range. At the same time, it effectively avoids the agglomeration of aluminous sillimanite crystals and the stratification of raw materials, providing a solid foundation for the uniform combination of the bonding phase during subsequent high-temperature sintering, and increasing the qualified product rate to over 99%.

The equipment adopts a fully enclosed static pressure screw, nut, and special heavy-duty bearing transmission structure. During operation, a stable high-pressure oil film is formed for protection, achieving flexible and uniform pressure application and gradual pressurization. This completely avoids the severe impact force and stress concentration problems caused by traditional rigid pressurization. The pressurization process is smooth and gentle, with uniform and soft pressure transmission. It can not only fully expel the internal pores of the green body and disperse the agglomeration of aluminous sillimanite crystals, completely eliminating defects such as porosity, stratification, and micro-cracks, but also gently protect the activity of aluminous sillimanite crystals, avoiding green body cracking and edge damage, significantly reducing the waste of high-cost raw materials, and effectively extending the service life of the mold, reducing material costs, and improving the production efficiency of the enterprise.

Breaking through the structural limitation of the fixed lower dead point of traditional equipment, a stepwise forging forming mode is adopted. According to the material, size, and structural complexity (such as hot blast stove lining bricks, glass kiln bricks, and special-shaped parts) of aluminous sillimanite bricks, as well as the density requirements, the stroke of the slider, the pressurization depth, and the applied pressure can be flexibly adjusted to precisely match the forming needs of various aluminous sillimanite bricks, covering the full range of production scenarios for high-end refractories. There is no need to worry about the problems of uneven pressurization caused by deviations in raw material filling volume, differences in particle size distribution, and changes in the fluidity of the mixture. Combined with a rapid mold change system, the mold change is convenient and efficient, perfectly adapting to the flexible mode of multi-variety and batch production, meeting the batch supply requirements of high-end fields.

The equipment is equipped with a dedicated forming parameter database for aluminous sillimanite bricks, integrating the optimal forming process parameters for various specifications, different raw material ratios, and different density requirements of aluminous sillimanite bricks, including common products such as standard aluminous sillimanite bricks, special-shaped aluminous sillimanite bricks, and high-strength thermal shock-resistant aluminous sillimanite bricks. Operators can retrieve them with one click, eliminating the need for repeated debugging and exploration, and significantly reducing the interference of human factors on product quality. All forming parameters can be permanently saved and reused in batches, ensuring that the density, compactness, and dimensional accuracy of each batch and each product are highly consistent, and the aluminous sillimanite crystal bonding phase is evenly distributed, easily meeting the strict quality requirements of high-end fields at home and abroad, and helping enterprises smoothly open up the overseas high-end refractory market.

Compared with traditional friction presses, the Haloong servo screw press adopts an intelligent mode of on-demand start-stop and sleep energy saving. The servo motor only operates during the pressing process, and the standby state is completely zero energy consumption, with a comprehensive energy-saving rate of over 55%, significantly reducing the electricity cost of aluminous sillimanite brick production, meeting the green and low-carbon development needs of the refractory industry. At the same time, the static pressure transmission structure has minimal wear, combined with a fully automatic forced lubrication system and an oil shortage alarm device, achieving maintenance-free operation, with a low equipment failure rate and a service life far exceeding that of traditional equipment, reducing the later maintenance and operation costs by more than 40%, comprehensively compressing production, operation, and material costs, and helping enterprises achieve a green, low-carbon, and efficient profit-making production model.

The equipment is equipped with standardized industrial communication interfaces, which can be seamlessly linked with automatic precise feeding machines, closed-loop distribution machines, intelligent demolding machines, non-destructive testing equipment for green bodies, and constant-temperature conveyor lines, building an automatic and intelligent forming production line for aluminous sillimanite bricks. It realizes unmanned control throughout the process from distribution, pressing, pressure maintenance, demolding to green body transportation and inspection, minimizing human intervention. This not only avoids damage to the green body caused by manual operation but also ensures forming accuracy and production efficiency. It supports remote monitoring, parameter debugging, fault early warning, and production data traceability functions, facilitating domestic and foreign customers to manage production progress and product quality in real time from different locations. It fully conforms to the global refractory industry's trend of intelligent, digital, and green transformation, and helps enterprises build an intelligent production base for high-end alumina red mullite bricks.

Zhengzhou Haloong Machinery Co., Ltd. is a leading enterprise in the domestic electric servo screw press field. For 45 years, it has always focused on technological innovation in refractory forming equipment, delved into the pain points of the forming process of high-end refractory products such as alumina red mullite bricks, and insisted on empowering the refractory industry upgrade with customized technology. The Haloong HLDS series of CNC servo screw presses cover the full tonnage range from 200T to 1600T. According to the material, specifications, production capacity, density, and raw material ratio requirements of customers' alumina red mullite bricks, it provides one-to-one customized forming solutions, fully meeting the mass production needs of various alumina red mullite bricks, and adapting to the supply of refractories in different high-end high-temperature, strong thermal shock, and strong erosion fields.