How is injection molding acrylic cosmetic organizer
1, injection molding machine selection
PMMA has no special requirements for injection molding machines. Because of its high melt viscosity, deeper grooves and larger diameter nozzle holes are required. If the strength of the product is required to be high, the low temperature plasticization is carried out using a screw having a large aspect ratio. In addition, PMMA must use a dry hopper to store material.
2, mold and gate design
The mold temperature can be 60 ° C -80 ° C, the diameter of the main channel should match the inner taper, the best angle is 5 ° to 7 °, if you want to injection 4mm or more products, the angle should be 7 °, the mainstream diameter is up to 8 To 10mm, the overall length of the gate should not exceed 50mm.
For products with a wall thickness of less than 4 mm, the runner diameter should be 6-8 mm
For products with a wall thickness greater than 4 mm, the runner diameter should be 8-12 mm
The depth of the edge, sector and tab gates should be 0.7 to 0.9 t (t is the wall thickness of the product), the diameter of the needle gate should be 0.8 to 2 mm; the lower viscosity should be smaller.
Common vents are 0.05 to 0.07 mm deep and 6 mm wide
The draft angle is between 30'-1° cavity portion 35'-1°30°.
3, the temperature of the melt
It can be measured by the air injection method: from 210 °C to 270 °C, depending on the information provided by the supplier.
4, injection temperature
Rapid injection can be used, but to avoid high internal stress, multi-stage injection should be used, such as slow-fast-slow, etc. When spraying thick parts, slow speed is used.
5, staying time
If the temperature is 260 ° C, the residence time is no more than 10 minutes. If the temperature is 270 ° C, the residence time should not exceed 8 minutes.
