Ring die service life analyze of wood pellet mill
Biomass solid molding technology includes wood pellet, wood briquette and wood brick, etc, it is used to increase the density of the biomass matter for large scale application of biomass matter as fuel, while the imperfect working principle and immature design and manufacture of wood pellet machinery can affect the production a lot: short service life of the machine and the key part-ring die is the bottle neck of the biomass solid molding industry development.
One study in Shang dong university shows that the shape, diameter, aspect ratio, arrangement and the number of the die hole could affect the service life of the die: the dies with the holes which are alternately arranged last longer than ones with die holes arranged in parallel; ring die with elliptical hole last longer than the ones with round holes, and with the same crafts and material, the hardness ratio is 3:2.
The working principle of ring die has decided its worn way-metal fatigue damage: cyclic bending stress and contact pressure, which are caused by the roller pressing and the friction between raw material and ring die, cracks are more likely to occur and ring die would not be in good shape for production.