Rock Wool Board Production Line For Fire Protection

In the field of building safety and industrial fire protection, fire-resistant rock wool boards have become an indispensable material due to their excellent non-combustible properties, high-temperature resistance and thermal insulation performance. The production line that specializes in manufacturing fire-resistant rock wool boards is a complex integration of multiple technologies, covering raw material processing, high-temperature melting, fiber formation, curing molding and other key links. Each process is closely linked and strictly controlled to ensure that the final product can meet the harsh requirements of fire protection scenarios. Understanding the operation mechanism, technical characteristics and quality control points of this production line is of great significance for improving the level of fire protection engineering and ensuring the safety of people's lives and property.

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The production of fire-resistant rock wool boards starts with the selection and pretreatment of raw materials, which lays the foundation for the fire performance of the final product. The main raw materials are natural volcanic rocks, among which basalt accounts for more than 70% due to its high content of silica and alumina, which can ensure the high temperature resistance and chemical stability of the fibers. In addition, some industrial slags can be properly added to the raw materials to reduce production costs, but strict control of impurity content such as sulfur and chlorine is required to avoid corrosion of metal components in subsequent applications. The raw material pretreatment process is mainly to crush the large-sized rocks into particles with a particle size of no more than 5cm, and remove impurities such as metal blocks and soil through screening equipment. This step is crucial because impurities will not only affect the quality of the molten magma, but also may damage the production equipment. After crushing and impurity removal, the raw materials are mixed in a certain proportion according to the product formula, and then sent to the silo for storage through the conveyor system, waiting for the next step of processing.

High-temperature melting is a core process in the production of fire-resistant rock wool boards, which directly determines the quality of the fibers. The mixed raw materials are transported to the melting furnace through the automatic feeding system, and the common melting equipment includes cupolas and electric furnaces. The temperature in the furnace needs to be strictly controlled between 1400°C and 1600°C, which is high enough to completely melt the solid raw materials into a uniform liquid magma. The stability of the melting temperature is particularly important. Too low a temperature will lead to incomplete melting of the raw materials, resulting in uneven fiber thickness; too high a temperature will increase energy consumption and may affect the physical properties of the fibers. During the melting process, professional operators monitor the state of the magma in real time through observation ports and temperature sensors, and adjust the feeding speed and heating power in time to ensure the stability of the melting process. The molten magma flows out from the discharge port of the furnace and is introduced into the fiber forming equipment through the flow channel, entering the next critical link of fiber formation.

Fiber formation is the key link to realize the special structure and performance of rock wool boards. At present, the mainstream fiber forming processes in the industry are centrifugal method and spray blowing method. The centrifugal method is widely used in the production of high-quality fire-resistant rock wool boards because it can produce finer and more uniform fibers. The specific process is that the molten magma is sent to a high-speed rotating centrifugal roller, and under the action of centrifugal force, the magma is thrown out through the small holes on the roller and stretched into fine fibers with a diameter of 4-7μm. The rotation speed of the centrifugal roller is usually not less than 3000 revolutions per minute, and the high rotation speed ensures the fineness and continuity of the fibers. The spray blowing method uses high-pressure air or steam to blow and stretch the magma sprayed from the nozzle into fibers. This method has the advantage of low cost, but the produced fibers are relatively thick, with a diameter of 8-12μm, and the uniformity is not as good as that of the centrifugal method, so it is mostly used in the production of rock wool products for industrial equipment insulation with lower requirements. During the fiber formation process, a certain amount of binder and water repellent are sprayed synchronously. The binder is usually phenolic resin, accounting for 3%-5% of the fiber weight, which is used to bond the fibers together; the water repellent is mostly silicone-based, which can make the final rock wool board have a water repellency rate of more than 98%, preventing moisture absorption from affecting fire performance and thermal insulation effect.

After the fibers are formed, they enter the fiber collection and curing molding stage. The fibers mixed with binder and water repellent are sucked into the cotton collection chamber under the action of negative pressure, and accumulate on the conveyor belt to form a uniform fiber mat. In order to improve the uniformity of the fiber mat and the bonding strength between layers, some advanced production lines adopt a pendulum cotton spreading process. The pendulum machine spreads the fibers layer by layer on the conveyor belt, and forms a multi-layer structure through the slope generated during spreading, which makes the fibers partially distributed vertically, thereby improving the compressive strength and interlayer bonding strength of the final product. After the fiber mat reaches the specified thickness, it is transported to the curing furnace by the crawler conveyor for curing treatment. The curing temperature is controlled between 180°C and 220°C, and the curing time is 10-30 minutes depending on the thickness of the mat and the type of binder. During the curing process, the binder undergoes a cross-linking reaction, bonding the loose fibers into a solid rock wool board blank with a certain strength. The temperature and time control in the curing furnace is very critical. Too low a temperature or too short a time will result in insufficient curing, low strength of the board blank, and easy delamination; too high a temperature or too long a time will cause the binder to decompose, affecting the performance and service life of the product.

After curing, the rock wool board blank needs to go through cooling, cutting and post-processing to form the final product. The high-temperature board blank coming out of the curing furnace is first cooled to room temperature by the cooling system to ensure the dimensional stability of the product. Then, the cooled board blank is sent to the cutting equipment, and cut into standard-sized rock wool boards according to the customer's needs and application scenarios. The common thickness of fire-resistant rock wool boards is 30-200mm, and the width is 600-1200mm. The cutting equipment usually uses circular saws or water jets. The water jet cutting method has the advantage of smooth cutting surface and no damage to the fiber structure, but the cost is relatively high; the circular saw cutting method is efficient and low-cost, and is widely used in mass production. In addition, some products need to go through post-processing procedures according to application requirements. For example, when used for external wall insulation, trapezoidal or dovetail grooves are opened on the surface of the board to enhance the bonding force with mortar; for some special scenarios such as pipeline insulation, aluminum foil or mortar coating is compounded on the surface to achieve moisture-proof and protective effects; some products also need to be pasted with glass fiber mesh cloth on the surface to improve crack resistance.

Quality inspection is an indispensable link in the entire production process, which ensures that the fire-resistant rock wool boards meet the application requirements. The quality inspection of fire-resistant rock wool boards covers multiple indicators, including physical properties, fire performance and environmental protection indicators. In terms of physical properties, the density is usually 80-200kg/m³, the compressive strength is not less than 40kPa, and the water absorption rate of water-repellent products is not more than 1%. In terms of fire performance, the core indicator is the non-combustible grade, which needs to achieve complete non-combustibility, no flame spread, no smoke and no burning droplets in the fire. In addition, the high-temperature shrinkage rate is also an important indicator. The shrinkage rate at 650°C should be less than 2% to ensure that the product can maintain its structural stability in the fire and play a role in fire prevention and smoke insulation. In terms of environmental protection indicators, the chloride ion content should be less than 100ppm to avoid corrosion of metal components, and the formaldehyde emission should meet relevant environmental protection standards to ensure that it will not cause harm to human health. After passing all the quality inspections, the qualified fire-resistant rock wool boards are packaged with plastic film or woven bags, stacked on pallets according to specifications, and stored in a dry and ventilated environment to avoid moisture affecting product performance.

The fire-resistant rock wool boards produced by this set of production line have a wide range of applications in the field of fire protection, and play an important role in passive fire protection systems. In building construction, they are widely used in fire partitions, fire ceilings, fire doors, curtain wall spandrel walls and various through-wall openings. For example, in the renovation project of the Queen Elizabeth Olympic Park in London, fire-resistant rock wool sealing strips and fireproof sealants were used to reinforce the fire resistance of linear joints and service tunnels, minimizing the risk of fire spread and ensuring the safety of fire escape routes. In industrial fields, fire-resistant rock wool boards are used for fire protection and insulation of high-temperature equipment such as industrial boilers, tanks and heat exchangers, as well as fire protection of ship bulkheads and ceilings. In addition, with the continuous improvement of building energy efficiency requirements, fire-resistant rock wool boards also play a role in energy saving and emission reduction while providing fire protection. They can effectively reduce heat transfer and heat loss, regulate indoor temperature, reduce the energy consumption of heating and cooling systems, and help reduce building operating costs. It is estimated that using one ton of rock wool insulation materials in buildings can save at least one ton of oil every year; using every cubic meter of rock wool in industrial thermal equipment can save up to 2500 kcal of energy per hour, equivalent to three tons of standard coal every year.

With the continuous development of fire protection technology and the continuous improvement of relevant standards, the fire-resistant rock wool board production line is also constantly upgrading and improving. In terms of energy saving and environmental protection, more and more production lines adopt electric melting furnaces instead of traditional coal-fired cupolas, which greatly reduces pollutant emissions and energy consumption. At the same time, the recycling of waste edges and the treatment of flue gas are also continuously optimized. The waste edges generated during the cutting process are crushed and reused as raw materials, improving the utilization rate of resources; the wet flue gas purification device is used to treat the flue gas generated during the production process to meet environmental emission standards. In terms of automation, the modern fire-resistant rock wool board production line has realized full-process automatic control from raw material batching, feeding, melting, fiber formation to curing, cutting and packaging. The electronic metering system ensures the accuracy of raw material ratio, the PLC control system realizes the precise control of temperature, speed and other parameters, and the automatic packaging machine improves the packaging efficiency and product consistency. These technological upgrades not only improve production efficiency and product quality, but also reduce manual operations and labor costs, promoting the sustainable development of the fire-resistant rock wool industry.

In conclusion, the fire-resistant rock wool board production line is a complex and sophisticated system engineering, which integrates multiple disciplines such as material science, thermal engineering and automatic control. Each link from raw material selection to final product packaging needs to be strictly controlled to ensure that the produced fire-resistant rock wool boards have excellent fire performance, physical properties and environmental protection performance. With the increasing emphasis on fire safety in various fields, the demand for high-quality fire-resistant rock wool boards will continue to grow, which will also promote the continuous innovation and development of production line technology. In the future, the fire-resistant rock wool board production line will tend to be more energy-saving, environmentally friendly, intelligent and efficient, while continuously improving product performance and expanding application fields, making greater contributions to improving fire protection safety levels and promoting green and low-carbon development.