High granule strength and resistance to crumbling—resulting in minimal loss during transport and storage—are not merely core indicators of product quality for fertilizer manufacturers; they are decisive factors for economic profitability and market competitiveness. Throughout the journey from the factory to the field, granules must withstand multiple stresses, including stacking pressure, vehicle vibrations, impacts during loading and unloading, and mechanical spreading. Any friction or impact can cause surface flaking or even total granule disintegration. The resulting dust leads to material loss, airborne dust pollution, uneven fertilization, and machinery clogs. Effectively mitigating these issues depends precisely on the combination of granule strength and surface density.

The root cause of crumbling during transport and storage is an insufficiently dense internal structure: the presence of numerous microscopic voids means intermolecular forces are too weak to withstand external impacts, while a loose surface structure makes the material prone to shedding dust through friction. Traditional wet granulation methods rely on water or steam to agglomerate materials; subsequent drying evaporates the moisture, leaving behind pores and a loose structure, while moisture migration and recrystallization during storage further compromise structural integrity. In contrast, the double-roller extrusion granulator employs a purely physical, dry, high-pressure forming process. This method thoroughly expels air from between particles, bringing solid particles close enough together for intermolecular forces to take full effect. Granule strength no longer relies on external binders but is achieved entirely through molecular-level cohesion driven by van der Waals forces and internal cohesive forces. Simultaneously, the high pressure creates a dense, smooth, hard outer shell, drastically reducing surface shedding caused by friction.

Ultimately, granule strength and surface abrasion resistance form the foundation of economic efficiency from the production line to the field. By utilizing high-pressure dry forming, the double-roller extrusion granulator imparts exceptional internal density and a smooth exterior finish to the granules, turning “resistance to crumbling” into a quantifiable metric and making “minimal loss” a reality. When every fertilizer granule reaches the crop’s root system intact, enterprises save on loss-related costs and farmers benefit from consistent fertilizer efficacy—this is the profound value of the “hard skill” that is granule strength.