The common sense problem solution in injection molding process

1. When the injection molding machine is just started, the product is running. After a period of production, the reasons and solutions for the lack of plastic in the injection parts are given. At the beginning of the injection molding machine material tube because of long heating time, melt viscosity is low, good liquidity, the product is easy to run over the front, after a period of production because of melt constantly take the heat away, resulting in the lack of melt, viscosity, poor liquidity, so that the product is short of glue. After a period of production, gradually raise the temperature of the feed tube to solve the problem.

2. In the production process, the product is short of glue, sometimes increasing the injection pressure and speed is ineffective, why? The solution? It is because the melting glue constantly takes the heat away in the production, resulting in insufficient melting glue, high viscosity and poor fluidity, so that the product is short of glue. Increase the temperature of the feed tube to solve.

3. Causes and solutions of product ellipse. The product ellipse is caused by uneven glue insertion, resulting in uneven pressure around the product, which makes the product ellipse. The three-point glue insertion is used to make the product even.

4. Mould requirements for precision products. The mold material is required to be rigid, elastic deformation is small, and thermal expansion coefficient is small.

5. The purpose of the product acid resistance test is to detect the internal stress of the product and the position of the internal stress point, so as to eliminate the internal stress of the product.

6. Reasons and solutions for easy cracking of metal inserts in products under stress. When placing inserts in the product, internal stress will be formed when hot melt glue meets cold inserts in beer molding, which will decrease the strength of the product and make it easy to crack. During production, the insert is preheated.

7. Rationality and selection method of mold exhaust point. The mold exhaust point is not reasonable, not only can not get the exhaust effect, but will cause the product deformation or size change, so the mold exhaust point should be reasonable. To select the exhaust point of the mold, exhaust should be opened at the place where the product is filled with glue at the end and where the product is trapped by gas burning.

8. Reasons and solutions for the brittle cracking of the product. Product brittle crack is the product use nozzle material and secondary material too much resulting in brittle crack, or the material in the material pipe stay time is too long, resulting in aging glue material, make the product brittle crack. Increase the proportion of new material, reduce the recycling times of nozzle material, generally not more than three times, to avoid the glue material in the material pipe for a long time.

9. The reason and solution of fiberglass products are prone to fiberglass flooding is that the fiberglass can not be well combined with the plastic in the glue because of the low melting temperature or the low mold temperature and the insufficient injection pressure. Increase the melt temperature, mold temperature, increase the injection pressure.

10. Influence of inlet temperature on products. The inlet temperature is too high or too low, will cause the machine return material is not stable, so that the feeding quantity is not stable, and affect the size and appearance of the product.

11. Causes and solutions of transparent products with white spots. The white spots of transparent products are caused by cold glue or dust inside the material. Increase the nozzle temperature, add cold material well, pay attention to the preservation of raw materials, prevent dust entering.

12. What is the injection capacity of an injection molding machine? ※※= Injection pressure (kg/cm2)× injection volume (cm3)/1000

13. What is the injection horsepower of the injection molding machine? Injection horsepower PW(KW)= injection pressure (kg/cm2)× injection rate (cm3/ SEC)×9.8×100%

At the beginning of the product running Pifeng, the production of a period of time after the product lack of glue reasons and solutions.

At the beginning of the injection molding machine material tube because of long heating time, melt viscosity is low, good liquidity, the product is easy to run over the front, after a period of production because of melt constantly take the heat away, resulting in the lack of melt, viscosity, poor liquidity, so that the product is short of glue. After a period of production, gradually raise the temperature of the feed tube to solve the problem.

14. Spherical screen printing after cracking problem. Because of the stress on the surface of the product, it cracked after screen printing. Increase mold temperature, reduce stress; Stress can be relieved by annealing.

15. Eyeglass frame, easy to break at the mouth. The injection pressure and holding pressure are high, and the residual internal stress at the nozzle edge causes the product to be easily broken. Reduce the injection pressure and holding pressure as far as possible, and appropriately raise the mold temperature to solve the problem.