pvc cable material granulator - granulation method and process

PVC granulator can be used for deep processing and production of special materials for lining. The specific process is as follows:

Specific methods and precautions:

1. The process parameters are the core elements of the extrusion granulation of PVC granulator. If the process parameters are incorrect, even the best formula and the best PVC cable granulator will be difficult to produce qualified products. Whether the process parameter setting is reasonable directly affects whether the semi-finished product is fully mixed and plasticized evenly, and whether the preliminary pre-plasticizing effect can be achieved; otherwise, it will not only cause problems in product appearance and performance, but also in deep processing (extrusion of cable inner lining). It is easy to produce abnormal quality.

2. In the process of collecting, crushing, demagnetizing and sorting waste PVC cable materials, foreign objects should be carefully selected, and PE, XLPE and other materials and PVC cable tapes should not be mixed. Copper, aluminum and other metals and wood chips must be separated to ensure waste PVC cables. The material is clean and free of debris.

3. The waste PVC cable material after crushing and bagging is stirred and mixed at a mixing temperature of 70~85℃ for 4~5min, and the uniformly mixed PVC material is added to the double-stage plastic granulation unit for extrusion and granulation. The extrusion temperature It is (150±5)℃. The granulated pellets need to be dispersed and cooled to prevent the pellets from sticking.

4. During the secondary granulation of waste PVC cable material, the filter screen should be replaced regularly in strict accordance with the process requirements, and the exhaust device should be checked regularly. Generally, 3~4 layers of 60~100 mesh stainless steel filter screen (or copper filter screen) are replaced every 2~3h to prevent the filter screen from being broken by impurities and coke materials in the waste PVC cable material. As a result, the spark rate of the cable sheath is high, and voltage breakdown occurs.

5. It is necessary to strengthen the inspection of the exhaust device of the cable material granulator to avoid the leakage of the exhaust device and cause the vacuum pressure to decrease, and it is difficult to discharge the decomposition products and water vapor such as HCl, CO2, CO, etc., resulting in pores and pinholes in the lining layer. The pay-off performance of the process is poor, and the appearance of the cable product is rough and not smooth.

6. The special PVC material produced by secondary granulation should be used in time, and it should not be placed for too long to avoid moisture absorption and dampness of the material. It is recommended that the placement time should not exceed 1 month.