Here are the causes and solutions described last week.
The causes and solutions of the shortcomings of plastic molding (1)
1. Hairy head, flying edge.
Fault causes and solutions.
(1) plastic temperature is too high to reduce the plastic temperature, reduce the mold temperature injection speed is too high to reduce the injection speed.
(2) Injection pressure is too high to reduce the injection pressure.
(3) Filler is too full to reduce the injection time, speed, and dose.
(4) Poor clamping line or anastomosis surface to repair the mold.
(5) Clamping pressure is not enough to increase the clamping pressure or replace the injection molding machine with a higher mold pressure.
2. When opening the mold or ejecting the finished product, rupture failure causes handling methods filler too full to reduce the injection pressure, time, speed, and injection volume.
(1) The mold temperature is too low to raise the mold temperature.
(2) Part of the mold release angle is not enough to repair the mold.
(3) There is a release chamfer to repair the mold.
(4) The finished product can not be balanced out of the mold when unmolded.
(5) The ejector pin is not enough or inappropriate position.
(6) Local vacuum phenomenon when demoulding open the mold can be ejected slowly, add into the air equipment demoulding agent is not slightly enough to increase the amount of demoulding agent.
(7) Poor mold design, finished products have excess stress within the finished product design side slider action time or improper overhaul mold.
3. Combined line.
Fault causes and solutions.
(1) Poor plastic melt improves plastic temperature, increases back pressure, speeds up the screw speed mold temperature is too low to improve mold temperature.
(2) Injection nozzle temperature is too low to raise the injection nozzle temperature.
(3) Injection speed is too slow.
(4) Injection pressure is too low.
(5) The plastic is unclean or seeping with other materials to check the plastic.
(6) The amount of mold release oil is too much or not.
(7) The sprue and overflow are too big or too small. Adjust the mold.
(8) The where the molten glue is joined is too far from the sprue mouth to adjust the mold.
(9) The air inside the mold is not enough to open the vent hole or check if the original vent hole is blocked.
(10) Too much mold release agent is not used or reduces the release agent.
4. Flow pattern.
Failure causes treatment methods.
(1) Poor plastic melting raises the plastic temperature, increases the backpressure, speeds up the screw speed mold temperature is too low raise the mold temperature.
(2) Improper cooling of the mold and re-adjust the mold water pipe.
(3) Injection pressure is too high or too low. Adjust the proper injection pressure.
(4) The plastic is unclean or seeping with other materials.
(5) The spillway is too small to produce the injection pattern and increase the spillway.
(6) The difference between the thickness of the finished section and the thinness of the finished product is too much.
5. The surface of the finished product is not glossy.
Failure causes treatment methods.
(1) Mold temperature is too low to improve the mold temperature.
(2) The plastic dose is not enough to increase the injection pressure, speed, time, and dose mold cavity have too much mold release oil wipe clean.
(3) Improper drying treatment of plastic improves drying treatment.
(4) There is water on the surface inside the mold, wipe test and check whether there is water leakage.
(5) The surface inside the mold is not smooth, polish the mold.
6. Silver pattern, bubble.
Failure cause treatment method.
(1) The plastic contains water, and the plastic is dried thoroughly to increase the backpressure.
(2) The temperature of the plastic is too high, or the plastic stays in the barrel for too long to reduce the temperature of the plastic, replace the injection molding machine with a smaller injection volume, reduce the nozzle and the temperature of the other additives in the plastic such as lubricants, dyes, etc. The amount of use or replacement of higher temperature resistant substitutes.
(3) Uneven mixing of other additives in the plastic and thorough mixing.
(4) Injection speed is not fast. Slow down the injection speed.
(5) The injection pressure is too high, reduce the injection pressure.
(6) The melting speed is too low to increase the melting speed.
(7) The mold temperature is too low to increase the molding speed.
(8) Uneven thickness of plastic grains use granular and uniform raw materials.
(9) Air is trapped inside the melt glue brief lower the temperature of the back section of the melt glue cylinder, increase the backpressure, and reduce the compression section’s length.
(10) Improper flow of plastic in the mold, adjust the size and position of the overflow, keep the mold temperature average, and average the thickness of the finished product.
