When selecting equipment for a small fertilizer plant, one must consider not only the purchase price but also the long-term maintenance costs. Although both flat die and pan granulators are suitable for small-scale production, their maintenance cost structures differ.

For flat die pelleting machines, maintenance centers on the replacement of wear parts. The die and pressure rollers—which come into direct, high-pressure contact with the material—are the primary wear components; they typically require replacement once or twice a year, costing approximately 2,000 to 3,000 RMB per instance. These parts can generally be refurbished two or three times before final replacement, helping to amortize long-term costs. Bearings and belts have longer service lives, requiring inspection or replacement only every two to three years. Pulverizing raw materials to a size below 3mm can extend the lifespan of wear parts by about 30%. Annual maintenance costs can be kept under 10,000 RMB, with routine upkeep—primarily replacing dies and rollers—easily handled by a standard maintenance technician.

The wear parts for pan granulators consist mainly of scraper tips and wear-resistant liners. Scraper tips require replacement every one to two months, while liners need changing every three to six months. Belts and bearings have service lives of 6–12 months and 12–18 months, respectively. Routine maintenance involves tasks like applying grease and checking bolts, requiring minimal technical expertise. However, disc granulators have a lower tolerance for moisture variations in the raw material; excessive moisture can cause material to stick to the pan, leading to frequent shutdowns for cleaning and indirectly increasing labor costs.

Overall, there is little difference in maintenance costs between the two. Expenses for flat die pelleting machines are concentrated on the periodic replacement of dies and rollers, making costs predictable and consistent. While disc granulators have cheaper daily consumables, they are less adaptable to fluctuating operating conditions, and the hidden costs associated with downtime for cleaning must be factored in. Small fertilizer plants should choose based on raw material characteristics: flat die pelleting machines are better suited for high-fiber materials, whereas pan granulators offer greater flexibility when dealing with diverse raw materials and significant moisture fluctuations.