What is the processing temperature of WPC granulation machine?
The WPC granulation temperature is a critical parameter affecting the quality of WPC products. By regulating key factors such as material melting conditions, interfacial bonding between wood fibers and plastic matrix, and material stability, it directly impacts the mechanical properties, appearance, durability, and processing stability of the products. Therefore, properly setting the WPC granulation temperature is crucial for quality control in wood-plastic composite WPC products.
Below are the recommendations from Yongte's engineering team regarding the processing temperature for PE and wood composition granulation process:
1， Feeding area: 50-80℃
Function: This is to preheat the material, but should avoid raw materials (especially wood fibers) due to sudden high temperature caused by local drying and cracking, and reduce feeding resistance.
2， Compression zone: 120-150℃
Function: Within this zone, materials undergo compaction and initial melting. Wood fibers begin to bond with the PE matrix. The temperature must exceed the glass transition temperature of PE (approximately-10℃) while remaining below the peak melting point to prevent over-melting and material overflow. (LDPE has a melting point of approximately 105-115℃, HDPE around 125-135℃ – this range enables both initial PE melting and material compaction.)
3， Melting zone: 150-170℃
Function: PE plastic should be completely melted in this zone, and wood fibers should be evenly dispersed in the molten plastic. The temperature should ensure complete melting, but it is recommended not to exceed 200℃ (to ensure full PE melting, HDPE should be close to the upper limit, LDPE can approach the lower limit, avoiding exceeding 180℃. PE has good thermal stability, but high temperatures may cause slight carbonization of wood fibers).
4， Harmonization zone: 140-160℃
Function: This zone can stabilize the melt pressure, make the material mixing more uniform, and the temperature is slightly lower than the melt zone (to avoid excessive dilution of the melt leading to poor particle formation).
Yongte WPC granulation machine has designed with total of 10 heating zones, using high efficiency heating system, water cooling system, and automatic temperature control system, it achevies high energy saving and temperature control accuracy.
