PET preform common defects and the processing method

In the product processing molding time can found that many of the problems. Below we analyze the common defects.
1. Bubble: Because the internal air injection molding machine or produced gas lead to appeared in the bottle preform of the bridge.
Solve method: (1). Increase the screw back pressure
(2) Reduce barrel section temperature
2. Dock: Because hot shrinkage in the bottle preform the inside surface of the formation of raw materials phenomenon
Solve method: (1). the increase of injection
(2). The pressure increased pressure
(3). Reduce the heating temperature of the machine
(4). Check the water cooling system
3. Short injection: In a complete injection process, filling bottle preform not completely.
Solve method: (1) Increase the pressure time
(2)Increased injection velocity
(3)Increase the amount of raw material injection
4. Gate crystallization: The nozzle temperature was too high
Solve method: (1) Reduce temperature
(2) Check the mold runner of cold water way if there is pollution and congestion

Post by : Ophelia
Sales engineer
E-mail: sino1505@sinomould.com
Skype: sinomould-10