Rockwool products are an inorganic fiber material made from natural rocks (such as basalt and dolomite) through high-temperature melting and subsequent fiberization. They are widely used in building insulation, industrial insulation, and sound absorption. The production process is rigorous, requiring strict control of parameters at each stage to ensure product quality.
Raw material preparation and pretreatment are the first steps in production. High-purity natural rocks are selected, crushed, screened, and then mixed in appropriate proportions to ensure a stable chemical composition. Some processes may add a small amount of flux (such as fluorite) to lower the melting temperature and improve production efficiency.
High-temperature melting is the core step. The mixed raw materials are fed by a conveyor belt into a cupola or electric furnace, where they are melted into liquid magma at temperatures of 1450-1550°C. During this stage, the temperature and furnace atmosphere must be precisely controlled to prevent impurities from entering and affecting fiber properties. The fluidity of the molten magma directly affects the subsequent fiberization, so parameters must be monitored and adjusted in real time.
Fiberization is achieved through centrifugal spinning or high-pressure air injection. Molten magma is spun through high-speed centrifugal rollers, forming long, thin fibers. Alternatively, high-pressure air is used to disperse the magma flow into micron-sized fibers. This process requires controlled fiber diameter (typically 3-20 μm) and length distribution to ensure the thermal insulation and mechanical properties of the finished product.
During the collection and curing stage, the fibers are evenly spread by a collector, forming a loose felt. Subsequently, a pendulum method or three-dimensional laying technique is used to optimize the fiber layer structure and enhance tensile strength. The felt enters a curing furnace, where it is bonded with a binder such as phenolic resin at 180-250°C to form a stable sheet or tube product. Curing time and temperature directly affect the density and hardness of the finished product.
Post-processing and inspection include cutting, laminating (e.g., with aluminum foil), and packaging. Finished products are tested for thermal conductivity, hydrophobicity, compressive strength, and other indicators, and are not released until they meet national standards.
The rock wool production process utilizes multi-step coordinated control to create a highly efficient and environmentally friendly thermal insulation material that meets the stringent demands of modern construction and industry.