To enhance the durability of roller skins in double roller pess granualtors, a comprehensive approach is required—encompassing material selection, raw material pretreatment, standardized operation, proper adjustment, and routine maintenance. Only through such holistic control can one effectively minimize wear, uneven abrasion, and impact damage, thereby significantly extending the service life of the equipment. First and foremost, it is essential to select high-quality, wear-resistant roller skins; priority should be given to high-chromium alloy skins, which possess high hardness and superior wear resistance, making them suitable for the extrusion granulation of most fertilizers and powdered materials. For materials characterized by high hardness and severe abrasiveness, options such as tungsten carbide hardfacing or alloy thermal spraying can be selected to further boost resistance to both wear and impact, thereby fundamentally enhancing overall durability.

Secondly, meticulous attention must be paid to raw material pretreatment, specifically through strict iron removal and impurity elimination. A permanent magnetic iron remover and a screening device should be installed at the feed inlet to remove sand, gravel, metal fragments, and other hard impurities, thereby preventing hard objects from directly impacting or scratching the roller surfaces. Concurrently, the moisture content and particle size of the raw materials must be carefully controlled; excessive moisture can lead to material sticking to the rollers and causing localized overload wear, while insufficient moisture intensifies dry friction and accelerates abrasion. Maintaining an appropriate moisture level is therefore crucial for mitigating wear on the roller surfaces.

During operation, it is imperative to ensure a uniform feed rate so that the material is distributed evenly across the entire length of the rollers. This prevents scenarios where one side receives an excessive or insufficient amount of material, thereby avoiding the formation of annular grooves or uneven, one-sided abrasion. Furthermore, the working pressure and the gap between the rollers must be adjusted appropriately; the pressure should not be set too high, as excessive force can cause the roller skins to deform under overload and accelerate wear. Additionally, ensuring that the two rollers remain parallel is critical to prevent uneven gaps, which can lead to abnormal wear along the edges of the rollers.

On a daily basis, adherence to standardized operating procedures is mandatory. The machine should always be started and stopped under a no-load condition to avoid the severe impact shock that occurs when starting up with material already loaded in the machine. At the end of every shift, any material adhering to the roller surfaces must be promptly cleaned off to prevent hard, caked lumps from scraping against and damaging the roller surfaces. Routine inspections should be conducted to monitor bearing lubrication, as well as the vibration levels and operating temperatures of the fertilizer production machine; if any abnormal noises or signs of unusual wear are detected, the machine must be shut down immediately for troubleshooting and repair. Should minor grooves or pits appear on the roller surfaces, they should be promptly repaired using wear-resistant hardfacing techniques and then ground smooth. This repair process can be repeated multiple times, thereby further extending the overall service life of the roller skins.