(1) Parameter setting

 

(2) Mold temperature: Moveable and fixed molds are produced by a mold temperature controller at 80℃.
(3) Injection pressure and speed: Injection pressure is set at 95-100bar, injection speed is 10-18, and holding pressure is 75bar.
(4) Plasticizing temperature: Plasticizing temperature, set at 275-285℃

(1) There is no missing material near gate, and silver thread is unstable.
(2) Defect ratio (%): 30%
(3) Frequency (times/hour):
(4) Loss amount (yuan/day):

(1) Parameter setting 1

(2) Moveable and fixed molds are produced using a mold temperature controller, and temperature is 80℃, unchanged.

(3) Injection pressure and speed: As shown in figure above, the first speed and position have changed.

(4) Plasticizing temperature: Same as above.
(5) Injection time is increased from 5.5 seconds to 10 seconds.

(1) Product quality status: Silver thread ratio has dropped significantly, and there is missing material at the bottom edges on both sides of gate.
(2) Silver thread defect ratio (%): 30% to 5%
(3) Frequency (times/hour):
(4) Amount of loss (RMB/hour):

Molding process analysis
Injection parameter analysis: Injection speed of the first stage is reduced, which can effectively control cold material from rushing into mold. Injection speed of the last two stages is gradually increased to ensure that product is fully filled. Increase in injection time is to ensure sufficient injection time and product surface shrinkage. However, because speed of the first stage is 5%, position is from 68 to 55, and stagnation occurs at bottom edge, resulting in material shortage.

 

(1) Product glue flow status

 

(2). There is material shortage on both sides of gate of product with slow glue flow on upper side

 

(3) Why is there material shortage so close to gate?
Product wall thickness is 2.6mm, bottom edge thickness is 1.4mm, width is 2mm, and side gate is opened at wall thickness of 2.6mm. When the first stage is 5% from 68 to 55, molten material moves forward quickly along thick wall and moves slowly at the edge. After stagnant part cools down, filling at the back cannot be filled, causing material shortage.

 

 

Molding process analysis
Injection parameter analysis:
The first section speed is 5%, position is from 68 to 58, and lack of material caused by stagnation at the bottom edge is improved. Main reason is that stagnant melt can be pushed forward to fill product while it is still in the state.

In this case, some measures are taken for process debugging when there is a lack of cold well in mold and there is stagnation in low-speed injection near gate position. Some rules for setting PC material parameters can be seen from injection molding process parameters. At the same time, stagnation is also a common flow phenomenon that needs to be paid attention to. And product defects caused by stagnation can be eliminated by adjusting process parameters.