When sourcing a PVC/PP mixer, you must prioritize the motor power and heating method. For high-speed mixers, ensure the motor is equipped with a frequency inverter to protect against current surges. The mixing tank should be constructed from SUS304 stainless steel with a thickness of at least 6-8mm to withstand high-friction heat. Additionally, verify the sealing structure of the main shaft; triple sealing (mechanical, packing, and air seals) is essential to prevent powder leakage into the bearing housing.