Tel：0512-65685025
Fax：0512-65650370
Email：sales@hanke-nmc.com
Website：http://www.hanke-nmc.com
Add: Block 7, No.19, Xingnan Road, Wuzhong, Suzhou City, Jiangsu, China
Name：Rebecca Dong
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Technical |
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Injection molding problem solving. |
Injection molding problem solving.
1. The product runs on the front when the product is started, and the reason and solution for the product lack of glue after production for a period of time.
Just switched on when the melt due to injection molding machine material tube heating time is long, low melt viscosity, good fluidity, the product easy to run front, production after a period of time due to the melt constantly take heat away, cause insufficient melt, viscosity, liquidity is poor, make the products lack of glue.
After a period of production, gradually increase the temperature of the material tube to solve.
2. In the process of production, the product lacks glue and sometimes increases the injection pressure and speed. Why? The solution?
It is because the melt glue in production keeps the heat away, resulting in the lack of glue, large viscosity and poor liquidity, which makes the product lack of glue.
Raise the temperature of the material tube to solve.
3. Causes and solutions of product ellipse.
The product ellipse is caused by inhomogeneity of glue, resulting in uneven pressure around the product, which makes the product ellipse, and is sent to the gush by the Chinese people. Br /,
4. Requirements of precision products for molds.
It is required that the mould material is rigid, the elastic deformation is small, and the thermal coefficient is small.
5. Purpose of acid test.
The acid test of the product is to test the internal stress and the position of the internal stress, so as to eliminate the internal stress of the product.
6. Reasons and solutions for the cracking of metal inserts in the products.
The product is inserted into the product. When the beer is molded, the hot melt adhesive meets the cold insert, which can form the internal stress, which makes the product strength drop and easy to crack.
Preheat the inserts during production.
7. Rationality and selection method of mold exhaust point.
The exhaust point of the mold is not reasonable. Instead of the exhaust effect, it will cause the deformation or size change of the product, so the exhaust point of the mold should be reasonable. Select the mold exhaust point, should be in the product at the end of the place where the glue and the product is trapped in the place to open the exhaust.
8. Causes and solutions of brittle products.
The product is brittle crack is the product USES the water mouth material and the secondary material too much causes the product to be brittle crack, or the material in the material tube stays the time too long, causes the glue material aging, makes the product fragile crack. Increase the proportion of the new material, reduce the amount of the recycling of water mouth, generally not more than three times, and avoid the long stay in the material pipe.
9. The cause and solution of fiberglass products are easy to appear.
It is due to the low temperature of the melt glue or the low mold temperature, the injection pressure is insufficient, so that the glass fiber can not be combined with the plastic in the glue, so that the fiber can be spread out. High melt temperature, mold temperature, increase injection pressure.
10. Influence of inlet temperature on products.
Too high or too low inlet temperature will result in unstable machine return, which will make the adding quantity unstable and affect the size and appearance of the product.
11. Transparent products have white points for reasons and solutions.
Transparent products have white spots because they are caused by cold glue in the product or dust in the material.
Raise the nozzle temperature, add the cold well, the raw material should be saved to prevent the dust from entering.
12. What is the injection capability of the injection molding machine?
Injection capacity PK= injection pressure (kg/cm2) x injection volume (cm3) /1000.
13. What is injection molding machine injection horsepower?
Injection pressure (KW) = injection pressure (kg/cm2) x injection rate (cm3/ SEC) x 9.8 x 100%.
14. What is the injection rate of the injection molding machine?
The injection rate V (cc/ SEC) =p/4 * d2 * g.
D2: material tube diameter g: material density.
15. What is the injection thrust of the injection molding machine?
The injection thrust F (KGF) =p/4 (d12-d22) * p * 2.
D1: cylinder internal diameter D2: piston rod external diameter P: system pressure.
16. What is the injection pressure of the injection molding machine?
Pressure P (kg/cm2) =[P /4 * (d12-d22) * P * 2] / (P /4 * d2)
17. What is the plasticizing capacity of the injection molding machine?
Plasticizing capacity W (g/SEC) = 2.5 x (d / 2.54) 2 x (h / 2.54) / 2 * S * N 1000/3600
H = the front tooth depth (cm) S= material density.
What is system pressure? What is the difference between the injection pressure and the injection pressure?
The system pressure (kg/cm2) = the highest working pressure in the oil pressure circuit. The injection pressure refers to the actual pressure in the injection molding, and the two are not equal.
19. Requirements for hydraulic oil of injection molding machine:
(1) proper viscosity and good viscosity-temperature performance.
(2) good lubrication and rust resistance;
(3) good chemical stability, not easy to gasify into gelatin;
(4) good foaming;
(5) less corrosive to the machine parts and sealing devices;
(6) flash point (flash point) requires low freezing point.
20. Effect of hydraulic oil viscosity on injection molding machine?
When system working environment temperature is higher, should be used in high viscosity oil, on the contrary, low viscosity oil should be adopted, the system working at high pressure, high viscosity, should be adopted for in high pressure, seal more difficult, leakage is the main problem, on the other hand, the system pressure is low, appropriate USES smaller oil viscosity, when the working parts of the hydraulic system of high speed, the oil flow is high, the pressure loss will also increase, and the leak quantity is less, appropriate USES low viscosity oil, on the other hand, the working parts movement speed is low, appropriate USES high viscosity oil.
21. Set a retreat.
The correct position of loosening is equal to the moving position of the rubber ring and the off-side distance of the screw.
22. The importance of loosening the position setting.
The release position is too large, which will cause the back material to absorb oxygen, which will oxidize and produce bubbles. The position is set too small, so that the pressure inside the cylinder is large, the shear force is too high to break the glue material, and the nozzle is salivated.
The position error shall not exceed 0.4mm.
23. Setting of the melting position.
Melting position = weight of the product/(maximum stroke/maximum melt amount)
24. Main advantages of pneumatic injection molding (GAM).
It can make hollow pipe fitting, which can save material and shorten cycle time.
In injection molding, the gas can be used to evenly distribute the pressure. When the plastics are cooled and solidified, the gas can be compensated by expanding the shrinkage of the plastic. Reduce the internal stress of molded products, thus improve the appearance stability, eliminate deformation and warping phenomenon.
25. Small inside diameter of piston rod, two big problems?
Due to the uneven shrinkage of the central hole needle, the diameter of the piston rod is small in the middle and at both ends. The medium hole needle can be made by the heat-dissipated copper material, and the mold is discharged in the middle part of the product.
26. Cracking problem after spherical screen printing.
Due to the stress on the surface of the product, the screen is cracked after the screen printing. The stress can be eliminated by means of annealing.
Eyeglasses frame, water edge is easy to break.
The injection pressure and pressure pressure are large, and the residual stress at the edge of the water outlet causes the product to be easily broken. Minimize the injection pressure and pressure pressure, and properly improve the mold temperature to solve.
28. Electrical shell, four assembly posts, crack problems when beating screws.
Because the column has a clamping waterline, it is easy to crack the product assembly column. The mold increases the exhaust, improves the mold temperature appropriately, and speeds up the speed of the injection.
Clip waterline.
29. Product deformation problem.
The deformation of the product is mainly caused by the imbalance of the thermal shrinkage, or the deformation of the product due to the internal stress of the product itself.
30. Bubble problem of transparent PC shell.
Insufficient drying of raw materials; The product has the uneven thickness of glue, the mold exhaust is bad, the raw material easy to break down can cause the product bubble.
Fully dry raw materials, increase the mold exhaust, reduce the thickness of glue as far as possible.
31. Photocopiers, magnetic materials of beer molding problems.
High - mode temperature should be used for rapid injection.
32. Product package glue, water edge shrinkage problem.
The mold exhaust is poor, the injection speed is slow, the pressure pressure and the time is not enough, all can cause the water mouth shrinkage.
Increase the mold exhaust, increase the injection speed, increase the pressure and time.
33. The internal stress of the product causes the product to burst after a period of time.
Due to the residual stress in the product, the product will burst after a period of time due to stress.
To improve the mold temperature and reduce the injection pressure, to eliminate the stress of the product, the product can be annealed to eliminate the stress.
34. When ABS material is used in black color, the product is liable to break and peel.
It is the pigment used in the color mother for too many reasons, resulting in the product peeling.
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