The blade is one of the important vulnerable parts of the PVC mixer
, and the wear is mainly shown in the following aspects:
The uniform plasticizing process of PVC materials is determined by the temperature of high mixing materials. Too low hot mixing temperature and uneven plasticization of PVC materials affect the performance of PVC profiles; If the hot mixing temperature is too high, PVC materials are easy to degrade in the mixing tank, even “paste”, which affects production.
Therefore, in general, most PVC profile manufacturers take 120 ℃ as the rated temperature index of hot mixing. When the amount of calcium carbonate is large, the hot mixed discharge temperature can be appropriately increased to facilitate the balanced adsorption of calcium carbonate by PVC materials and low melting point components and increase the apparent density.
In addition to the need to control the hot mix discharge temperature, it is also necessary to pay close attention to the hot mix time to monitor the discharge temperature control. In case of continuous mixing, if the time for hot mixing to reach the discharge is short (such as less than 7 min), the interval time of each batch shall be extended;
When the mixer is used for a long time, if the temperature rises too slowly (for example, the discharge temperature cannot be reached after more than 12 minutes), the material can be unloaded in time, and the thermocouple and thermometer should be carefully checked for failure and handled.
When it is found that the blade of the mixer is seriously worn, it should be replaced in time to prevent affecting the quality of the mixture. In general, when the mixing time exceeds 2 times of the normal mixing time or the blade end wear is greater than 15 mm, the blade shall be replaced.
Repair refers to repair welding of the worn parts of the blade. Pay attention to the welding angle and position during repair welding. The angle will affect the mixing effect of the equipment, and the position deviation will affect the balance of the equipment. If the balance is unstable, the equipment will vibrate greatly during operation, and the bearing will be damaged if it is used for a long time. It is recommended that users use wear-resistant steel electrodes for repair welding and do dynamic balancing after welding, If replacement is required, contact the equipment manufacturer to customize thickened wear-resistant blades.