The ring mold and roller group of the biomass pellet machine are key working parts of the molding machine. Many users only know how to damage and replace the abrasives and roller group without finding the reason why the roller group wears quickly, resulting in the increase in the cost of consumable parts. Today, the editor will help you analyze: the reasons for the serious wear of the roller group of the biomass pellet machine.

The outer circumferential surface of the roller group is processed into a cogging shape, because the roller group is subjected to friction and squeeze pressure for a long time. The working conditions of the roller group are relatively bad. In addition to the normal wear of the raw materials on the roller group, biomass raw materials such as straw and wood chips mostly contain sand, gravel, silicide, and iron filings, which aggravates the wear of the roller group.

Since the linear velocities of the roller group and the ring mold are basically equal, the diameter of the roller group is only 0.4 of the inner diameter of the ring mold, so the wear rate of the roller group is 2.5 times higher than that of the ring mold. The theoretical design life of the roller group is 800h, but the actual use time does not exceed 600h. Due to improper use, some users have used less than 500 hours, and the failed pressing roller cannot be repaired due to severe surface wear. The pressure roller wears too quickly, which not only reduces the forming rate of the particulate fuel and increases production costs, but also directly affects the productivity.

In addition, when the pressing roller is severely worn, the depth of the wear layer exceeds 70% of the thickness of the pressing roller working layer, the forming rate of the biomass particles has dropped below 75%. We believe that it has failed. At this time, the grabbing ability of the pressing roller is significantly reduced, the discharge speed is reduced, the bulk material increases, and the outer surface pits increase rapidly.

When the roller group of the biomass pellet machine is rubbed, the surface of the hard abrasive particles cause local plastic deformation of the surface of the roller group, and the abrasive particles are embedded and cut into the metal surface, resulting in gradual loss of the surface of the part until the carburized layer almost disappears. Not only does the crushed straw act as abrasive particles, but the raw materials contain impurities of hard material with larger particles such as iron filings and sand particles, which interlock with the roller group, causing pits, scratches, etc. on the roller group surface. The wear of the roller group is basically the same as the wear mechanism of the inner surface of the ring mold, and both have wear marks.