Control factors of injection molding cycle

Control factors of injection molding cycle :

Cycle cycle: Injection molding is a comprehensive technology, which is related to the time of each step. It directly affects the time for the polymer solid melt and the product to go through the thermal process and the force, and affect the product quality and production efficiency.

In the molding cycle, the main part is the injection holding time, cooling time, mold opening time and demolding time. The complete cycle consists of closing the door-closing the mold-injection pressure holding-screw measurement-cooling-opening the mold-ejecting the product-opening the door to pick up parts (there is no such thing when fully automatic).

There is no human factor of closing and opening the door in the fully automatic cycle, it is controlled by time setting. It can be seen from the molding cycle that the factors that affect the cycle process affect product quality.

The molding cycle setting should minimize the cycle of each program segment under the premise of ensuring product quality. When closing and opening the door, the program adopts a semi-automatic cycle that requires manual control to participate in the program. The operator is required to quickly open or close the door after the time is up, and try to make the time of each stay equal. Otherwise, the accumulated time error will also affect the thermal history of the plastic.

When the mold is closed by time control (when fully automatic cycle), the product will fall, and it will be delayed for about 1s after inspection. The time of closing the mold phase should be adjusted according to the speed-speed-speed-speed and low pressure protection and conversion time. When adjusting, the movable template should be considered to work under the conditions of small inertia impact and protection of human body and mold.

The injection holding pressure and the measuring time of the screw depend on the properties of the polymer, the product and the mold, and are related to many factors such as injection pressure, injection speed, screw revolutions, back pressure, and temperature. Seek a shorter time under the premise of ensuring quality. The number of screw revolutions and back pressure directly affect the measurement time of the screw, and the efficient screw is used to reduce the program time.

The setting of the cooling time should consider the properties of the polymer, the product and the temperature and other conditions. The studio recommends that it be completed within the very short cooling time required for the product.

Under the same mold temperature and demolding temperature, the mold filling melt temperature is high and the cycle is long. Under the same demolding temperature, when the mold temperature is low, the molding cycle is short.