In addition to the abnormal phenomena similar to extrusion blow molding, multi-layer hollow blow molding machines may also have two abnormal phenomena.

1. Delamination of products

1. The melt temperature of the bonding layer is too low, and the material is not well plasticized. Appropriately increase the temperature of the bonding layer to change the bonding performance.

2. The melt temperature of the bonding layer is too high, and it is attached to the adjacent layer to make the bonding layer uneven. Appropriately reduce the temperature of the bonding layer.

3. The temperature of the blow mold is too low, and the bonding layer in the product is plasticized too quickly and is not firmly bonded to the adjacent layer. Control the medium flow rate to avoid too low mold temperature.

4. The raw material contains moisture, and the raw material should be dried.

2. Uneven barrier layer in the product

1. The melt temperature of the barrier layer is too low or too high, readjust the corresponding extruder temperature and extrusion rate.

2. The extruder pressure fluctuates, the extrusion speed is unstable or the screw structure is improper.

3. There is retention or degradation in the die head. Improve the flow channel of the die head according to the fluidity of the material to avoid retention.

The failure of multi-layer hollow blow molding machine is mainly related to the extruder and the die head of the preform, so the extruder screw structure and control accuracy are required to be high. In addition, the flow channel design of the die head is also very important.

The multi-layer hollow blow molding machine is fully automatic computer controlled, equipped with an accurate integrated PID temperature control system, and the extrusion pressure of each screw is detected in real time. It can realize centralized control, interlocking protection and warning functions, has automatic flash removal function, and can be equipped with a 100-point wall thickness control system.

The multi-layer hollow blow molding machine can greatly reduce the thickness of the small and medium layers without affecting the permeability barrier performance of the product through accurate control, thereby greatly reducing the cost of the composite bottle, which is currently close to the level of glass bottles. The composite bottle itself has the advantages of light weight and not easy to break, so it can be an ideal substitute for glass bottles and has broad market prospects.