Injection molding common problem
1, injection molding products warp and contraction deformation causes?
Answer: 1, cylinder temperature is too low; 2, short forming period; 3, the injection pressure is too high; 4, the injection speed quickly; 5, the holding time is too long; 6, uneven mold temperature, should adjust the mould cooling system, setting up reasonable cooling circuit; 7, gate section is too small; 8, ejection mechanism design is unreasonable, should try to increase the out area and point out; 9, die strength is insufficient, should try to increase its rigidity.
2, what is the causes and solutions of product ellipse?
A: ellipse is uneven due to the rubber products, product all round pressure not divide evenly, make products to elliptic. Solution: use 3 into the glue, make the product into the glue.
3 when using black color masterbatch, ABS, peeling products is easy to break, how to solve?
A: mother color pigment used in the carbon powder is overmuch, cause product peeling. Replaceable mother color pigment.
4, white products appear black spots, mixed color, how to control?
Answer: 1, the raw material. In the process of mixing materials, ingredients, pay attention to clean, prevent the impurities, mixed with dust; 2, the machine. (1) inside the cylinder to clean, screw on the presence of carbonized layer and rubber product; (2) the screw head, nozzle flange and nozzle parts whether matter, inner surface smooth and no dead Angle phenomenon; (3) the screw head for wear and tear, screw to install center degrees whether meet the requirements, presence of oscillating phenomenon. 3, mold. Mold flow channel without acute Angle, injection points shoulds not be too small.
5, injection molding products owe note the cause and the elimination method have?
A: plastic injection products owe note the cause and the elimination method basically has: 1, the melting temperature is too low, will raise the cylinder and nozzle temperature; 2, molding cycle is too short, should be appropriately extended; 3, low injection pressure, should be appropriate increase; 4, the injection speed too slow, should be appropriate to speed up. 5, the holding time is short, should be appropriately extended; 6 and underfeeding, should increase for shoes; In July and screw back pressure on the low side, should be appropriate increase. 8, gating system structure of small size, should be appropriate amplification and gate flow channel section. 9, mold venting is not good, should increase the vent, improve the exhaust performance of mold; 10, die strength is insufficient, should try to improve the rigidity of the die.
6, injection machine inlet temperature have any impact on product?
Answer: the inlet temperature too high or too low, can cause the machine back to the material is not stable, make add capacity is not stable, affect the size and appearance of the product.
7, set the injection molding process step is what?
A: set the injection molding process steps: 1, set the temperature of melting; 2, set mold temperature; 3, set screw dislocation and speed; 4, set back pressure; 5, set maximum injection pressure to the machine; 6, set pressure; 7, set injection speed; 8, set the holding time; 9, set the sample cooling time; 10, set to open mould time; 11, setting out board stroke; 12, minimize the holding time.
8, the main reason for the injection molding products have flash? What are those?
A: the main cause of injection molding products have flash are: 1, the template is not flat, or template insufficient rigidity and deformation; Haven't enough 2, clamping force, mold locking; 3, the injection pressure is too high; 4, raw material MFR value too high, the melt viscosity is low; 5, material temperature, mold temperature is too high.