When the plastic material is squeezed by the rollers, the particles will deform or flow, and a strong van der Waals attraction will occur. So let's summarize what conditions will affect the vertical pellet mill's granulation quality?

(1) In order to obtain a better extrusion effect, the feeding force should be different in size, and its suitable range should be controlled at 0.1-1mm. Materials that are too fine (less than 0.1mm) contain too much air, which will affect the compactness of the finished material, and will affect the extrusion process (cause the vibration of the extruder to increase), and materials that are too large will consume a lot of crushing energy . Therefore, the feed particle size should be well controlled.

(2) The hardness or plasticity of the material affects the pressure used in the extrusion process. Some materials, such as diamine phosphate and urea, have better plasticity, and the effect of extrusion into granules is better. Potassium sulfate, ammonium sulfate, and phosphate rock powder have poor plasticity and are not easy to extrude into granules. In order to achieve better results, an appropriate amount of adhesive can be added. Urea or a small amount of water can act as a bond.