Product details
According to the characteristics and feeding conditions of TPR materials, the appearance and technological properties of TPR materials shall be generally inspected before forming. TPR pellets often contain different levels of moisture, flux and other volatile low molecular substances, especially the moisture content of TPR with hygroscopic tendency always exceeds the limit allowed by processing.
Therefore, it is necessary to carry out drying treatment and measure the water content before processing. Under high temperature, the moisture content of TPR is required to be below 5%, even 2% ~ 3%, so vacuum drying oven is usually used to dry at 75℃ ~ 90℃ for 2 hours.
The dried materials must be properly sealed and stored to prevent the materials from losing drying effect due to moisture absorption from the air. For this reason, the hopper in the drying chamber can continuously provide dry hot materials for the injection molding machine, which is beneficial for simplifying operation, keeping clean, improving quality and increasing injection rate. The loading capacity of the drying hopper is generally 2.5 times that of the injection molding machine per hour.
Before the newly purchased injection molding machine is used for the first time, or when products need to be changed, raw materials need to be changed, colors need to be changed, or decomposition phenomenon is found in plastic, the barrel of the injection molding machine needs to be cleaned or disassembled. Cleaning machine barrel generally adopts heating machine barrel cleaning method. Cleaning materials generally use plastic raw materials (or plastic recycled materials). For TPR material, the transition cleaning material can be replaced by the processed new material.
