2025/09/16
The double roller press granulator is the core equipment for pellet production. Its stable operation directly affects product quality and the production efficiency of the fertilizer production line, requiring precise control from multiple dimensions.
Raw material pretreatment is fundamental. The raw material moisture content must be appropriate for the product type. For organic fertilizers, keep it between 25% and 35%, and for compound fertilizers, between 8% and 12%. A moisture content that is too high can easily stick to the rollers, while a moisture content that is too low can cause the pellets to break. An online moisture meter is recommended for real-time adjustment. Furthermore, the raw material particle size must be ≤ 1/3 of the die hole diameter. Metal, stone, and other impurities must be removed through a de-ironing device and screening machine to prevent scratches on the roller surface and damage to components.
Control of core components is crucial. The rollers must be made of suitable material: 65Mn steel for soft raw materials and high-chromium alloy for hard raw materials. The die hole tolerance should be ≤ ±0.1mm. During installation, parallelism should be calibrated with a dial indicator, with an error of ≤0.02mm/m. Use spherical roller bearings and refill with high-temperature lithium-based grease every 8-12 hours. The transmission system must ensure that gear meshing clearance and coupling coaxiality meet standards to prevent roll misalignment.
Optimizing process parameters is key. Extrusion pressure must be tailored to the raw material: 8-15 MPa for organic fertilizer and 15-25 MPa for compound fertilizer. Avoid excessive pressure (excessive motor load) or excessive pressure (loose pellets) that is too low. Roller speed is controlled between 5-15 r/min, and the feed rate is adjusted using a variable frequency feeder to ensure linkage with roller speed and pressure to prevent blockage or insufficient output.
Daily maintenance is essential. Before starting the machine, clean any remaining material and inspect lubrication and protective devices. During operation, monitor pellet quality, bearing temperature, and equipment noise every two hours. Perform a weekly thorough inspection of the roller surface and gearbox, and replace worn parts monthly to ensure long-term, stable operation of the organic fertilizer equipment.
