Environmental protection cosmetics packaging aluminum tube brittle plastic products, such as the reason analysis

Environmental protection cosmetics packaging aluminum tubes and other environmental protection cosmetics packaging aluminum tube products appear crisp cause analysis: product design: ( 1) Products with prone to stress cracking of sharp corners, gaps, or thickness vary widely. （ 2) Product design is too thin or hollow out too much. Mold: 1) Gate is too small, should consider to adjust the opening size or addition shop gate. （ 2) Distributary channel is too small or misallocation, should try to arrange reasonable balance or increase distributary channel size. （ 3) The mould structure bad cause abnormal injection cycle. Equipment: 1) Barrel inside corner or obstacles, easy to promote the molten material degradation. （ 2) Machine plasticizing capacity is too small, plastic inside the barrel plasticizing inadequate; Machine plasticizing capacity is too big, plastic inside the barrel is heated and the shearing action time is too long, plastic easy to aging, make the products become fragile. （ 3) Ejection device is tilted or imbalance, dry area small or poor distribution. Process: 1) A barrel, nozzle, low temperature, raised it. If the material easy degradation, should raise the temperature of barrel, nozzle. （ 2) Reduce the screw plastic back pressure and rotational speed, make the material a little loose, and to reduce the degradation caused by shear overheating. （ 3) Mold temperature is too high, demoulding difficulty; Mold temperature is too low, plastic cooling overheating, fusion welded seam bad, easy to crack, especially when high melting point, such as polycarbonate plastic. （ 4) Want to have the appropriate draft type cavity bleeding. Type secrete difficult demoulding, to improve the mold temperature, shorten the cooling time. Cavity is difficult to take off, want to lower the temperature in the cavity, extend the cooling time. （ 5) As far as possible with a metal insert, such as polystyrene plastic of this kind of specific volume of brittleness of cold heat is big, more can insert molding. Raw materials: 1) Raw materials mixed with other impurities or with improper or excessive solvent or other additives. Poor quality plastic itself, such as molecular weight, contains the uneven structure such as molecular chain rigidity is too large in the number of components; Or other plastic doping pollution, harmful additives, dust pollution of impurities is also the cause of brittle. （ 2) Some plastics such as ABS, under the condition of be affected with damp be affected with damp heat and water vapor will happen catalytic cracking reaction, result in large strain of parts. （ 3) Environmental protection cosmetics packaging aluminum tube regeneration frequency or reworked material content is too high, or within the barrel heating time too long, cause embrittlement of fabrication.